ALBERT

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Electrochimica Acta, Volume 319〈/p〉 〈p〉Author(s): Subish John, Samba Siva Vadla, Somnath C. Roy〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉CuO is a narrow band gap 〈em〉p〈/em〉-type semiconducting material having a wide range of applications. However, it is quite challenging to obtain phase pure CuO nanostructures grown directly on Cu substrate as most of the synthesis techniques like thermal oxidation results in the formation of additional Cu〈sub〉2〈/sub〉O phase. In this work, we report the growth of CuO nanoflakes without the formation of Cu〈sub〉2〈/sub〉O by a facile two-step synthesis process which consist of electrochemical anodization of Cu foil followed by low-temperature hydrothermal treatment at 100 °C. The phase purity of the sample is confirmed through XRD, XPS, and HRTEM. Further, photocurrent response of the sample is evaluated, and a rapid thermal treatment was used to improve the photo-response without altering the phase and morphology of the CuO nanoflakes. Such a process at 400 °C for 10 s resulted in a high photocurrent density of −4.6 mAcm〈sup〉−2〈/sup〉 (at 0.05 V 〈em〉vs.〈/em〉 RHE under AM 1.5G conditions). Electrochemical impedance spectroscopy and Mott Schottky analysis shows the direct role of rapid thermal treatment in increasing the charge carrier density of the sample.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0013468619313337-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Electrochimica Acta, Volume 319〈/p〉 〈p〉Author(s): Cong Liu, Fenyun Yi, Dong Shu, Weixin Chen, Xiaoping Zhou, Zhenhua Zhu, Ronghua Zeng, Aimei Gao, Chun He, Xia Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Three-dimensional N/S co-doped succulent-like hierarchical carbon (3D NS-SHC) is synthesized by carbonization of a supramolecular cluster. In this supramolecular process, potassium citrate can act as a reliable carbon source, while the thiourea as a N/S source and then, two molecules gradually tend to generate a giant “all-in-one” precursor via hydrogen bonding verified by Independent Gradient Model (IGM) calculation. TEM and SEM images show the N/S co-doped carbon holds a novel 3D succulent-like hierarchical structure. For NS-SHC-8:8 sample, element mapping images display the uniform N/S atoms distribution. These distinct features can be related to the supramolecular polymerization which promotes in-situ N/S co-doping homogenously and conduces to build 3D structure. Typically, NS-SHC-8:8 electrode exhibits prominent specific capacitance (258.5 F g〈sup〉−1〈/sup〉 at 0.5 A g〈sup〉−1〈/sup〉) and excellent cycle stability (94.4% after 20000 cycles) in three-electrode system. Furthermore, an assembled quasi-solid state symmetric supercapacitor delivers good energy density (10.2 Wh kg〈sup〉−1〈/sup〉 at 250 W kg〈sup〉−1〈/sup〉) and steady cycle endurance (85.1% after 10000 cycles). These eximious behaviors of NS-SHC-8:8 are mainly attributed to (1) the uniform N/S atoms distribution and their synergistic effect, which brings extra Faradaic reaction to higher specific capacitance, (2) the charming 3D succulent-like hierarchical structure, which serves as a multifunctional reservoir that can accommodate the ion/charge and facilitate their migration to further promote the electrochemical performance. Above mentions suggest that this uniformly heteroatom-modified carbon material produced by supramolecular technique is promising for high-performance energy storage devices.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0013468619313283-fx1.jpg" width="296" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Electrochimica Acta, Volume 319〈/p〉 〈p〉Author(s): Arunprabaharan Subramanian, Mahadeo A. Mahadik, Jin-Woo Park, In Kwon Jeong, Hee-Suk Chung, Hyun Hwi Lee, Sun Hee Choi, Weon-Sik Chae, Jum Suk Jang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Herein, we report the surface treatment on Zr〈sup〉4+〈/sup〉/Al〈sup〉3+〈/sup〉 codoped α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 photoanode for high-performance photoelectrochemical water splitting. A high-temperature quenching exhibits the Zr〈sup〉4+〈/sup〉/Al〈sup〉3+〈/sup〉 codoping in α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 photoanode without damaging morphology. The presence of Zr〈sup〉4+〈/sup〉/Al〈sup〉3+〈/sup〉 codoping shows a cathodic shift in onset potential, but lack of increment in photocurrent reveals the major role of passivation and the minimum doping effect of aluminum. Additionally, CoO〈sub〉x〈/sub〉 cocatalyst exhibits increment in photocurrent with the greater cathodic shift in onset potential than the pristine α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 nanorods. The CoO〈sub〉x〈/sub〉 surface-reworked Zr〈sup〉4+〈/sup〉/Al〈sup〉3+〈/sup〉 codoped α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 photoanode displays the highest photocurrent of 1.5 mA/cm〈sup〉2〈/sup〉 at 1.23 V vs. RHE (76% increment over the pristine α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉) and 0.7 mA/cm〈sup〉2〈/sup〉 at 1.0 V vs. RHE (102% increment over the pristine α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉). The systematic characterization carried out using x-ray diffraction and scanning electron microscopy confirms that after Zr〈sup〉4+〈/sup〉/Al〈sup〉3+〈/sup〉 codoping, and surface treatment, the crystalline structure, and morphology of the photoanodes remains unchanged. X-ray photoelectron spectroscopy confirmed the existence of Zr〈sup〉4+〈/sup〉/Al〈sup〉3+〈/sup〉 codopants in the hematite nanostructure. The electrochemical properties of the photoanode suggest that Al〈sup〉3+〈/sup〉 and Zr〈sup〉4+〈/sup〉 codoping, as well as surface treatment with CoO〈sub〉x〈/sub〉, cocatalyst lowers charge transfer resistance across the FTO/hematite interface, and hematite/electrolyte interface. This designs not only lowers onset potential but also offers the blueprint for the development of an efficient catalyst for solar water oxidation.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉CoO〈sub〉x〈/sub〉 surface-reworked Zr〈sup〉4+〈/sup〉/Al〈sup〉3+〈/sup〉 codoped α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 photoanode displays the 102% increment in PEC performance than pristine α-Fe〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 at 1.0 V vs. RHE.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0013468619312927-fx1.jpg" width="471" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Bioorganic & Medicinal Chemistry, Volume 27, Issue 16〈/p〉 〈p〉Author(s): Tao Li, Jing Li, Yang Yang, Yilin Han, Dirong Wu, Tao Xiao, Yang Wang, Ting Liu, Yonglong Zhao, Yongjun Li, Zeqin Dai, Xiaozhong Fu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The deficiency of nucleos(t)ide analogues (NAs) as anti-hepatitis B virus (HBV) drugs in clinical use is attributable to their insufficient enrichment in liver and non-target organ toxicity. We aimed to develop potent anti-HBV adefovir derivatives with hepatotrophic properties and reduced nephrotoxicity. A series of adefovir mono 〈span〉l〈/span〉-amino acids, mono cholic acid-drug conjugates were designed and synthesized, and their antiviral activity and uptake in rat primary hepatocytes and Na〈sup〉+〈/sup〉-dependent taurocholate co-transporting polypeptide (NTCP)-HEK293 cells were evaluated. We isolated compound 〈strong〉6c〈/strong〉 as the optimal molecular candidate, with the highest antiviral activity (EC〈sub〉50〈/sub〉 0.42 μmol/L, SI 1063.07) and highest cellular uptake in primary hepatocytes and NTCP-HEK293 cells. In-depth mechanistic studies demonstrated that 〈strong〉6c〈/strong〉 exhibited a lower toxicity in HK-2 cells when compared to adefovir dipivoxil (ADV). This is because 〈strong〉6c〈/strong〉 cannot be transported by the human renal organic anion transporter 1 (hOAT1). Furthermore, pharmacokinetic characterization and tissue distribution of 〈strong〉6c〈/strong〉 indicates it has favorable druggability and pharmacokinetic properties. Further docking studies suggested compounds with ursodeoxycholic acid and 〈span〉l〈/span〉-amino acid groups are better at binding to NTCP due to their hydrophilic properties, indicating that 〈strong〉6c〈/strong〉 is a potential candidate as an anti-HBV therapy and therefore merits further investigation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0968089619309034-ga1.jpg" width="327" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Bioorganic & Medicinal Chemistry, Volume 27, Issue 17〈/p〉 〈p〉Author(s): Bo Hou, Ze Liu, Xiao-Bei Yang, Wen-Fei Zhu, Jin-Yu Li, Liu Yang, Fu-Cai Reng, Yong-Feng Lv, Jiang-Miao Hu, Guo-Yang Liao, Jun Zhou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The stems of 〈em〉Dryopteris crassirhizoma〈/em〉, one of the main components of Lianhua-Qingwen Formula (LQF) was traditionally used for heat-clearing and detoxifying. Dryocrassin 〈strong〉ABBA〈/strong〉 is a key antiviral component in the herbal medicine while the compound is hard to get in large amounts with the features of homologous compounds, polyphenol groups, and low contents. Therefore, the present work aims to seek influenza H7N9 virus inhibitors from natural source by synthesis of dryocrassin 〈strong〉ABBA〈/strong〉 and its analogues. As a result, total synthesis of the compound was achieved in nine steps with an over-all yield of 4.6%. Neuraminidases (NAs) inhibitory activities of the synthesized product and its analogues were evaluated afterward. Comparing with the positive control, OSV (9.6 μM), it was very exciting that dryocrassin 〈strong〉ABBA〈/strong〉 and its analogues (〈strong〉b5〈/strong〉 and 〈strong〉e2〈/strong〉) showed better NAs inhibitory activity against Anhui H7N9 with IC〈sub〉50〈/sub〉 values of 3.6 μM, 2.5 μM and 1.6 μM. For the highly resistant Shanghai N9, these compounds can also show medium inhibitory activities. Docking results indicated the direct interaction of synthesized 3 hits with the key K294 by hydrogen bonds, but no direct interaction of OSV with the key K294 was observed in Shanghai N9. This study suggested that dryocrassin 〈strong〉ABBA〈/strong〉 and its analogues especially 〈strong〉AB〈/strong〉, which consisted of polyphenol groups may have beneficial effects on treating avian influenza H7N9 virus.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉Total synthesis of dryocrassin ABBA and analogue structures with potential inhibitory activity against drug-resistant neuraminidases.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0968089619308879-ga1.jpg" width="278" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics, Volume 1867, Issue 9〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Biomembranes〈/p〉 〈p〉Author(s): Deo R. Singh, Christopher King, Matt Salotto, Kalina Hristova〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉EGFR is a receptor tyrosine kinase that plays a critical role in cell proliferation, differentiation, survival and migration. Its activating ligand, EGF, has long been believed to stabilize the EGFR dimer. Two research studies aimed at quantitative measurements of EGFR dimerization, however, have led to contradicting conclusions and have questioned this view. Given the controversy, here we sought to measure the dimerization of EGFR in the absence and in the presence of saturating EGF concentrations, and to tease out the effect of ligand on dimer stability, using a FRET-based quantitative method. Our measurements show that the dissociation constant is decreased ~150 times due to ligand binding, indicative of significant dimer stabilization. In addition, our measurements demonstrate that EGF binding induces a conformational change in the EGFR dimer.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0005273619301476-ga1.jpg" width="265" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Carbon, Volume 153〈/p〉 〈p〉Author(s): Ayoub H. Jaafar, N.T. Kemp〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper reports on the first optically tunable graphene oxide memristor device. Modulation of resistive switching memory by light opens the route to new optoelectronic devices that can be switched optically and read electronically. Applications include integrated circuits with memory elements switchable by light and optically reconfigurable and tunable synaptic circuits for neuromorphic computing and brain-inspired, artificial intelligence systems. In this report, planar and vertical structured optical resistive switching memristors based on graphene oxide are reported. The device is switchable by either optical or electronic means, or by a combination of both. In addition the devices exhibit a unique wavelength dependence that produces reversible and irreversible properties depending on whether the irradiation is long or short wavelength light, respectively. For long wavelength light, the reversible photoconductance effect permits short-term dynamic modulation of the resistive switching properties of the light, which has application as short-term memory in neuromorphic computing. In contrast, short wavelength light induces both the reversible photoconductance effect and an irreversible change in the memristance due to reduction of the graphene oxide. This has important application in the fabrication of cloned neural networks with factory defined weights, enabling the fast replication of artificial intelligent chips with pre-trained information.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0008622319306943-fx1.jpg" width="485" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 3 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochemical and Biophysical Research Communications, Volume 516, Issue 4〈/p〉 〈p〉Author(s): Yanjie Hou, Tian Gong, Jiangtao Zhang, Xi Yang, Yurong Guo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The thinned-young apple polysaccharides from three varieties were obtained by hot water extraction at 88 ̊C for 120 min. The compositional monosaccharides of the three polysaccharides were shown to be the same (xylose, mannose, galactose and glucose) and the molecular weights of the polysaccharides were in the range of 200–300 kDa. Compared with “Qinyang” and “Pinklady”, the polysaccharide from “Jinshiji” had the highest emulsifying capacity. Moreover, the variations in pH and cation ion concentrations had also a significant effect on the emulsifying properties of the extracted polysaccharides. At pH 2.0–4.0, the prepared emulsion had smaller droplet sizes than at higher pH values. Although the emulsion was stable at low concentrations of Na〈sup〉+〈/sup〉 and Ca〈sup〉2+〈/sup〉 ions, high concentrations of Na〈sup〉+〈/sup〉 and Ca〈sup〉2+〈/sup〉 led to significant destabilization of the emulsion. Conclusively, our results demonstrated the potential application of thinned-young apple polysaccharide as a natural polysaccharide emulsifying agent.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics〈/p〉 〈p〉Author(s): Martina Paumann-Page, Rupert Tscheliessnig, Benjamin Sevcnikar, Romy-Sophie Katz, Irene Schwartz, Stefan Hofbauer, Vera Pfanzagl, Paul G. Furtmüller, Christian Obinger〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Human peroxidasin 1 is a multidomain peroxidase situated in the basement membrane. The iron enzyme with covalently bound heme oxidizes bromide to hypobromous acid which facilitates the formation of distinct sulfilimine cross-links in the collagen IV network and therefore contributes to its mechanical stability. Additional to the catalytically active peroxidase domain peroxidasin comprises a leucine rich repeat domain, four Ig domains and a C-terminal von Willebrand factor type C module (VWC). Peroxidasin has been shown to form homotrimers involving two redox-sensitive cysteine residues and to undergo posttranslational C-terminal proteolytic cleavage. The present study on several recombinantly produced truncated peroxidasin variants showed that the VWC is not required for trimer formation whereas the alpha-helical linker region located between the peroxidase domain and the VWC is crucial for trimerization. Our data furthermore implies that peroxidasin oligomerization occurs intracellularly before C-terminal cleavage. For the first time we present overall solution structures of monomeric and trimeric truncated peroxidasin variants which were determined by rotary shadowing combined with transmission electron microscopy and by small-angle X-ray scattering (SAXS). A triangular arrangement of the peroxidase domains to each other within the homotrimer was revealed and this structure was confirmed by a model of trimeric peroxidase domains. Our SAXS data showed that the Ig domains are highly flexible and interact with the peroxidase domain and that within the homotrimer each alpha-helical linker region interacts with the respective adjacent peroxidase domain. The implications of our findings on the structure-function relationship of peroxidasin are discussed.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S1570963919301219-ga1.jpg" width="240" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Carbon, Volume 153〈/p〉 〈p〉Author(s): C.M. Ramos-Castillo, M.E. Cifuentes-Quintal, E. Martínez-Guerra, R. de Coss〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Energy gap engineering in graphene nanostructures is one of the most important topics towards development of graphene-based electronics. In this work, based on the density functional theory, the role of the edge magnetism on the size dependence of Kohn-Sham gap and fundamental energy gap for 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"〉〈mrow〉〈msub〉〈mrow〉〈mtext〉C〈/mtext〉〈/mrow〉〈mrow〉〈mn〉6〈/mn〉〈mtext〉nn〈/mtext〉〈/mrow〉〈/msub〉〈msub〉〈mrow〉〈mtext〉H〈/mtext〉〈/mrow〉〈mrow〉〈mn〉6〈/mn〉〈mtext〉n〈/mtext〉〈/mrow〉〈/msub〉〈/mrow〉〈/math〉 (〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.svg"〉〈mrow〉〈mtext〉n〈/mtext〉〈mo linebreak="badbreak"〉=〈/mo〉〈mn〉2〈/mn〉〈mo linebreak="goodbreak" linebreakstyle="after"〉−〈/mo〉〈mn〉16〈/mn〉〈/mrow〉〈/math〉) hexagonal graphene quantum dots (GQDs) with zigzag edges is studied. We found a transition from a nonmagnetic to an antiferromagnetic state at a certain critical diameter (〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.svg"〉〈mrow〉〈mo〉∼〈/mo〉〈/mrow〉〈/math〉 3 nm), characterized by the opening of a Kohn-Sham gap as a consequence of the exchange interaction between localized edge states. Furthermore, the fundamental gap is obtained from the difference between the calculated vertical ionization and electron affinity energies. Such approximation includes relaxation in the exchange correlation potential when the electron is added to the system, which might be useful for GQDs transport properties interpretation. We found a scaling rule for the fundamental gap dependence on quantum dot size, providing a practical way to predict this property for large GQDs with zigzag edges, which currently in most demanding approaches, such as GW, is unfeasible.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0008622319306876-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 The International Journal of Biochemistry & Cell Biology, Volume 114〈/p〉 〈p〉Author(s): Deep Pooja, Anusha Gunukula, Nitin Gupta, David J. Adams, Hitesh Kulhari〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The biggest challenge in delivering anticancer agents is the ability to direct these molecules specifically to cancer cells. With this in mind, modern research is focussing on improving the precision of cancer drug delivery by incorporating a ligand that has the ability to specifically recognize cancer cells. Peptides are emerging as a new tool in drug and gene delivery. Peptide-drug conjugates, peptide-modified drug delivery systems, and peptide-coupled imaging agents have been shown to increase on-site delivery. This has allowed better tumor mass contouring in imaging and increased therapeutic efficacy of chemotherapies, reducing adverse effects. Benefits of peptide ligands include their small size, easy and affordable production, high specificity and remarkable flexibility regarding their sequence and conjugation possibilities. Bombesin (Bn) receptors have shown great promise for tumor targeting due to their increased expression in a variety of human cancers, including prostate, breast, small cell lung, and pancreatic cells. This review discusses the overexpression of Bn receptors in different cancers and various approaches to target these receptors for therapeutic and diagnostic interventions in human malignancies.〈/p〉〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Marine Systems, Volume 199〈/p〉 〈p〉Author(s): Peisheng Huang, Kerry Trayler, Benya Wang, Amina Saeed, Carolyn E. Oldham, Brendan Busch, Matthew R. Hipsey〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Effective short- and long-term estuarine water quality management decisions require a holistic view of estuarine response to multiple stressors that may be achieved through the integration of numerical modelling and observed data. Such an approach has been developed for the Swan-Canning Estuary system, a eutrophic urban estuary in Western Australia under threat from nutrient enrichment and a drying climate. Numerical modelling was integrated with long-term monitoring to develop the system Swan-Canning Estuary Virtual Observatory (SCEVO), which has been used to facilitate water quality management and streamline prediction workflows of hindcast, forecast, and environmental response functions. The system is based on a validated 3D water quality model, integrated within a data management system and related environmental models. A machine-learning method to improve the patchy and time-lagged catchment inputs is also highlighted. This work has identified that the key challenge associated with estuarine water quality prediction is the capability to (1) simulate internal physical and biogeochemical processes at suitable spatial resolution to resolve the gradients along the freshwater-ocean continuum; and (2) transition from using routine monitoring data as the basis for management decisions to using a diverse and integrated set of data streams as the basis for real-time operational decisions. Recommendations for high-frequency monitoring to support water quality modelling and dynamic integration between numerical and observed data for improved forecasting are discussed.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Physics and Chemistry of Solids, Volume 135〈/p〉 〈p〉Author(s): Lamya H. Al-Wahaibi, Yusuf Sert, Fatih Ucun, Nora H. Al-Shaalan, Aisha Alsfouk, Ali A. El-Emam, Mustafa Karakaya〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This research relates to the molecular structure, electronic properties and IR, Raman and XPS analyses of the potential chemotherapeutic agent namely, 5-(adamantan-1-yl)-〈em〉N〈/em〉-methyl-1,3,4-thiadiazol-2-amine. Another purpose is to explore the structural stabilities and consistencies and, to assess the stable interaction energy and intermolecular hydrogen bond geometry for its dimeric structure. The monomer and dimer optimizations of the molecule have been calculated by the DFT method using various functionals such as B3LYP, B3PW91, mPW1PW91 and M06-2X. Although the minimum energy optimization was calculated at the B3LYP functional, the BSSE-corrected and uncorrected interaction energies of the dimer structure were more effectively obtained with the M062X functional. This assured us a test of the efficiency of M06-Class functional calculations on intermolecular interactions of strongly bound systems. Additionally, the molecular docking study was done between our molecule (ligand) and the previously studied and known as cortisone reductase 11β-Hydroxysteroid dehydrogenase type 1 (receptor, 11-β-HSD1: PDB-2ILT).〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0022369718334346-fx1.jpg" width="455" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Physics and Chemistry of Solids, Volume 135〈/p〉 〈p〉Author(s): Hongfang Jiu, Na Ren, Lixin Zhang, Qing Zhang, Yuying Gao, Yajuan Meng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The flower-like ZnMn〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 hollow microtubules were synthesized by a hydrothermal method and calcination method. The composition and morphology were characterized. The results showed that flower-like hollow microtubules were obtained through calcination treatment. The as-prepared ZnMn〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 electrochemical properties of flower-like hollow microtubules anode material for lithium-ion batteries were investigated. The first charge and discharge capacity was measured at 2152/1263 mA h g〈sup〉−1〈/sup〉 when the current density at 400 mA g〈sup〉−1〈/sup〉. After 300 cycles, the capacity kept 515 mA h g〈sup〉−1〈/sup〉 corresponding to the coulombic efficiency of 99%, which exhibited preferable cycling performance. The stability of the structure has been shown by rate performance, which had been tested under different current density. The results suggest a promising application of the ZnMn〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 as anode material for lithium-ion batteries.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0022369718333468-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Physics and Chemistry of Solids, Volume 135〈/p〉 〈p〉Author(s): Takahiro Iijima, Tadashi Shimizu, Atsushi Goto, Kenzo Deguchi, Toshihito Nakai, Ryutaro Ohashi, Masayoshi Saito〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In Ti-based Ziegler-Natta catalysts (ZNCs), disagreements exist concerning which lateral surface of the MgCl〈sub〉2〈/sub〉 support adsorbs Ti species so as to be an active site for the catalysis of polymerization. In the present paper, we investigated the local structure of TiCl〈sub〉4〈/sub〉 adsorbed onto the surface of MgCl〈sub〉2〈/sub〉 by 〈sup〉47,49〈/sup〉Ti solid-state nuclear magnetic resonance (NMR) spectra at 21.8 T along with density functional theory (DFT) calculations. The magic-angle-spinning NMR spectrum of the TiCl〈sub〉4〈/sub〉/MgCl〈sub〉2〈/sub〉 adduct sample prepared by 20 h of milling, which exhibited broadened and shifted peaks compared to that of the sample without milling, was simulated by a Czjzek model considering the distribution of quadrupole interaction parameters. The electric field gradient and chemical shielding tensors of 〈sup〉49〈/sup〉Ti were obtained via DFT calculations for model molecules of TiCl〈sub〉4〈/sub〉, 2TiCl〈sub〉4〈/sub〉, and Ti〈sub〉2〈/sub〉Cl〈sub〉8〈/sub〉 adsorbed onto the (110), (104), and (104)-step defect surfaces of MgCl〈sub〉2〈/sub〉. By comparing the obtained NMR parameters, the 〈sup〉47,49〈/sup〉Ti NMR spectrum of the milled sample was assigned to TiCl〈sub〉4〈/sub〉 adsorbed onto the (104) surface of MgCl〈sub〉2〈/sub〉, which may not be a principal component of adsorption.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S002236971930472X-fx1.jpg" width="380" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Marine Systems, Volume 199〈/p〉 〈p〉Author(s): Arseny A. Kubryakov, Alexander S. Mikaelyan, Sergey V. Stanichny〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Bio-Argo measurements of the backscattering coefficient (〈em〉bbp〈/em〉) were used to investigate the time-depth evolution of coccolithophore blooms in the Black Sea. Five years of Bio-Argo data obtained in 2014–2018 revealed two distinct peaks of 〈em〉bbp〈/em〉 corresponding to the winter and early summer coccolithophore blooms. The latter started in the upper mixed layer (UML) in April–May and was characterized by the highest coccolithophore concentrations. During the most extensive summer bloom in 2017, its estimates reach 10 × 10〈sup〉6〈/sup〉 cells l〈sup〉−1〈/sup〉. The summer blooms occupied the UML (0–10 m) and a seasonal thermocline (10–30 m). The lower boundary of the bloom was related to the position of isopycnal 1014 kg m〈sup〉−3〈/sup〉, which deepens in May–July due to summer heating. Consequently, the coccolithophore bloom deepened to 20–30 m and terminated rapidly in July. Bloom termination was accompanied by a significant rise in light attenuation (〈em〉kd〈/em〉) in the sea basin. This peak was attributed to the release of dissolved organic carbon (DOC), which was possibly related to viral lysis and the exudation of lipids from coccolithophore cells. Data on the 〈em〉kd〈/em〉 was used to estimate the seasonal variability in DOC in the Black Sea. Maximal estimated values of DOC were observed at 15–35 m depth in June-August and coincided with the early summer coccolithophore bloom termination.〈/p〉 〈p〉The winter coccolithophore bloom started in October–November in the UML. The maximum 〈em〉bbp〈/em〉 was observed in January. High values of 〈em〉bbp〈/em〉 were observed down to a depth of 60 m during the maximal deepening of the mixed layer. The winter blooms were distinctly observed in MODIS satellite images, where they were characterized by high reflectance and relatively low chlorophyll concentrations. The estimated coccolithophore concentration in winter was lower than that in summer, but column-averaged 〈em〉bbp〈/em〉 values were comparable. The winter coccolithophore bloom reached a peak within one month after the autumn peak of chlorophyll A, indicating the possible importance of the nutrients recycled after the diatom autumn bloom. In contrast to summer, the maximum DOC observed at the surface preceded the winter coccolithophore bloom, and the mass DOC production was probably attributed to the excretion and lysis of the non-calcified phytoplankton cells.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Marine Systems, Volume 199〈/p〉 〈p〉Author(s): Yuanyi Li, Huan Feng, Haiwen Zhang, Jian Sun, Dekui Yuan, Lei Guo, Jing Nie, Jinglong Du〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The time required for water exchange characterizes the hydrodynamic condition of a water body, which is related to its self-purification ability. In this study, a numerical model based on a three-dimensional hydrodynamic model is established and implemented to calculate the age of water. Using the model, the spatial distribution and seasonal variation of the age of the water discharged into the New York/New Jersey (NY/NJ) Harbor from the Passaic River and the Hackensack River are calculated. The hydrodynamic conditions and the characteristics of water exchange in the harbor are analyzed from the perspective of age. The results indicate that the monthly-averaged age at the entrance of the NY/NJ Harbor is approximately 26 days and 40 days during the wet season and the dry season, respectively. River discharge has a significant impact on the spatial distribution of water age in the NY/NJ Harbor. Generally, high river discharge results in better water exchange and flushes contaminants out of the harbor quickly. However, discharges from several rivers flowing into the harbor interact and interfere with one another. Such interactions can improve or inhibit water and contaminant flushing from the harbor. The analysis of age variations and residual flows indicates that the Kill van Kull is one of the key channels controlling the contaminant transport and water quality in the Newark Bay. This study demonstrates the advantages of using water age to study the water exchange and physical self-purification ability of this complex harbor.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Contaminant Hydrology, Volume 226〈/p〉 〈p〉Author(s): Mehrdad Bastani, Thomas Harter〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Nitrate in drinking water may cause serious health problems for consumers. Agricultural activities are known to be the main source of groundwater nitrate contaminating rural domestic and urban public water supply wells in farming regions. Management practices have been proposed to reduce the amount of nitrate in groundwater, including improved nutrient management practices and “pump and fertilize” with nitrate-affected irrigation wells. Here, we evaluate the feasibility and long-term impacts of agricultural managed aquifer recharge (Ag-MAR) in the source area of public water supply wells. A numerical model of nitrate fate and transport was developed for the Modesto basin, part of California's Central Valley aquifer system. The basin is representative of semi-arid agricultural regions around the world with a diversity of crop types, overlying an unconsolidated sedimentary aquifer system. A local public supply well in an economically disadvantaged community surrounded by farmland was the focus of this study. Model scenarios implemented include business as usual, alternative low-impact crops, and Ag-MAR in the source area of the public supply well. Alternative nutrient management and recharge practices act as remediation tools in the area between farmland and the public supply well. Improved agricultural source area management practices are shown to be an effective tool to maintain or even enhance groundwater quality in the targeted supply well while remediating ambient groundwater.〈/p〉 〈p〉Best results are obtained when lowering nitrate load while also increasing recharge in the source area simultaneously. This scenario reduced nitrate in the supply well's drinking water by 80% relative to the business as usual scenario. It also remediated ambient groundwater used by domestic wells between the source area farmlands and the supply well and showed 60% more reduction of nitrate after 60 years of application. Increasing recharge led to shorter initial response time (five years) and showed the most sustainable impact. Our analysis further suggests that Ag-MAR in a highly discontinuous, wide-spread pattern leads to slow water quality response and may not yield sufficient water quality improvements.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Contaminant Hydrology〈/p〉 〈p〉Author(s): Héloïse A.A. Thouement, Tomasz Kuder, Timo J. Heimovaara, Boris M. Van Breukelen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Back-diffusion of chlorinated ethenes (CEs) from low-permeability layers (LPLs) causes contaminant persistence long after the primary spill zones have disappeared. Naturally occurring degradation in LPLs lowers remediation time frames, but its assessment through sediment sampling is prohibitive in conventional remediation projects. Scenario simulations were performed with a reactive transport model (PHT3D in FloPy) accounting for isotope effects associated with degradation, sorption, and diffusion, to evaluate the potential of CSIA data from aquifers in assessing degradation in aquitards. The model simulated a trichloroethylene (TCE) DNAPL and its pollution plume within an aquifer-aquitard-aquifer system. Sequential reductive dechlorination to ethene and sorption were uniform in the aquitard and did not occur in the aquifer. After 10 years of loading the aquitard through diffusion from the plume, subsequent source removal triggered release of TCE by back-diffusion. In the upper aquifer, during the loading phase, δ〈sup〉13〈/sup〉C-TCE was slightly enriched (up to 2‰) due to diffusion effects stimulated by degradation in the aquitard. In the upper aquifer, during the release phase, (i) source removal triggered a huge δ〈sup〉13〈/sup〉C increase especially for higher CEs, (ii) moreover, downstream decreasing isotope ratios (caused by downgradient later onset of the release phase) with temporal increasing isotope ratios reflect aquitard degradation (as opposed to downstream increasing and temporally constant isotope ratios in reactive aquifers), and (iii) the carbon isotope mass balance (CIMB) enriched up to 4‰ as lower CEs (more depleted, less sorbing) have been transported deeper into the aquitard. Thus, enriched CIMB does not indicate oxidative transformation in this system. The CIMB enrichment enhanced with more sorption and lower aquitard thickness. Thin aquitards are quicker flushed from lower CEs leading to faster CIMB enrichment over time. CIMB enrichment is smaller or nearly absent when daughter products accumulate. Aquifer CSIA patterns indicative of aquitard degradation were similar in case of linear decreasing rate constants but contrasted with previous simulations assuming a thin bioactive zone. The Rayleigh equation systematically underestimates the extent of TCE degradation in aquifer samples especially during the loading phase and for conditions leading to long remediation time frames (low groundwater flow velocity, thicker aquitards, strong sorption in the aquitard). The Rayleigh equation provides a good and useful picture on aquitard degradation during the release phase throughout the sensitivity analysis. This modelling study provides a framework on how aquifer CSIA data can inform on the occurrence of aquitard degradation and its pitfalls.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Continental Shelf Research, Volume 184〈/p〉 〈p〉Author(s): Israel Medina-Gómez, Ana Aguilar Trujillo, Ismael Marino-Tapia, Giuliana Cruz, Jorge Herrera-Silveira, Cecilia Enriquez〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Inorganic nutrients and phytoplankton (chlorophyll-〈em〉a〈/em〉 concentration and community variables) were studied under a hydrologic scenario defined by a joint topographic-hydrodynamic upwelling event and an algal bloom in the southeast Gulf of Mexico. To do so three oceanographic cruises (GOMEX series) were undertaken throughout the Yucatan shelf during: September 11th-21st of 2010, September 23rd-October 3 〈sup〉rd〈/sup〉 of 2011, and November 29th-December 9th〈sup〉,〈/sup〉 2012 (named as GOMEX-1, GOMEX-2 and GOMEX-3, respectively). We aim to assess the spatial inorganic nutrients and Chl-a patterns corresponding to each cruise to explore potential biochemical consequences of the temporal variability of the vertical inflow in the eastern shelf boundary (Cape Catoche: CC) and further spatial propagation of water featuring this hydrographic signature onto a shallow shelf, marked also by a high algal bloom incidence. This framework allows tackling the implications of the interplay between coastal variability and oceanographic processes on the phytoplankton biomass and community parameters. The spatial pattern of surficial Chl-a, as well as sub-surface maxima of ≈10 mgm〈sup〉−3〈/sup〉 concurrent with the 22.5 °C isotherm over the southeastern shelf area of CC supports the fact that vertical nutrients supply is removed from the euphotic layer through phytoplankton uptake. This scenario indicates a biochemical setting consistent with rapid transfer of external resources advected from deep levels, capable not only to enhance phytoplankton growth, but also to change its species composition. Vertical mixing conditions associated with N-NW winds (locally known as “nortes”) and a lack of upwelling scenario during GOMEX-3 in 2012 lead to relatively more homogeneous nitrate spatial distribution with overall high concentrations in deep, oceanic areas subject to nutrients entrainment. The distribution of specific richness among diatoms and dinoflagellates and relative abundance within such groups, as well as Chl-〈em〉a〈/em〉 concentrations are considered normal with regards to what has been observed in other studies for the Gulf of Mexico. The potential implications of large-scale, inter-annual climatic processes (e.g., El Niño-Southern Oscillation) on marine resources relevant to regional primary productivity variability (changes in the phytoplankton community) are discussed.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Chromatography B, Volume 1125〈/p〉 〈p〉Author(s): Roberta Natália Cestari, Adriana Rocha, Renê Donizeti Ribeiro de Oliveira, Vera Lucia Lanchote〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Gemfibrozil (GFZ) is a derivative of fibric acid and is used in the treatment of dyslipidemia. GFZ may affect the metabolism of various drugs, including statins, by inhibiting the sinusoidal influx transporter OATP1B1 and also CYP2C9 and CYP2C8 enzymes. This study presents the development and validation of a rapid, simple, sensitive and reproducible method of GFZ analysis in human plasma using UPLC-MS/MS. The method was applied in a pharmacokinetic study following administration of multiple doses of 600 mg GFZ every 12 h in healthy volunteers (〈em〉n〈/em〉 = 15). GFZ was separated on a C18 column using a mixture of 0.01% formic acid and acetonitrile (40:60, v/v) as the mobile phase at a flow rate of 0.4 mL/min. The method showed linearity in the range from 0.01 μg/mL to 100 μg/mL plasma. The coefficients of variation and the relative standard errors of the accuracy and precision analyses were 〈15%. The method allowed quantification of plasma concentrations of GFZ in the dose interval of the sixth day of administration of multiple oral doses of GFZ every 12 h. The pharmacokinetic parameters are presented as mean (95% CI): area under the plasma concentration 〈em〉versus〈/em〉 time curve 〈strong〉88.84〈/strong〉 (72.72–104.96) μg·h/mL, steady state mean plasma concentration 7.40 (6.06–8.75) μg/mL, minimum plasma concentration 1.24 (0.87–1.61) μg/mL, maximum plasma concentration 26.73 (21.31–32.15) μg/mL, time to reach maximum plasma concentration 2.28 (1.42–3.13) h, elimination half-life 2.81 (2.22–3.40) h, apparent total clearance 7.72 (5.85–9.58) L/h, apparent distribution volume 33.97 (18.41–49.53) L. In conclusion, the method for analysis of GFZ in human plasma showed sensitivity, linearity, precision and accuracy compatible with application in pharmacokinetic studies of multiple oral dose of 600 mg GFZ every 12 h.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Chromatography A〈/p〉 〈p〉Author(s): Jonas Henschel, Simon Wiemers-Meyer, Marcel Diehl, Constantin Lürenbaum, Wen Jiang, Martin Winter, Sascha Nowak〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The expansion of lithium ion battery (LIB) application is accompanied by the growth of battery pack sizes. This progression emphasizes the consideration of electrolyte safety as well as environmental aspects in case of abuse, accident, or recycling. Hexafluorophosphate is one of the most commonly used conducting salt anions in electrolytes. It has great potential to degrade to various acidic and non-acidic organo(fluoro)phosphates with presence of water and during battery cell operation. Consequently, toxicological investigation on these organo(fluoro)phosphates has emerged because they either have structural similarities as chemical warfare agents or play a widespread physiological role as phosphates in the human body. This circumstance underlines the need of isolated examination of these compounds for safety assessment. In this work, we used hydrophilic interaction liquid chromatography for the extraction of acidic organofluorophosphates from thermally aged LIB electrolytes. The developed two-step fractionation method provided high separation selectivity towards acidic head groups, which allowed the separation of undesired matrix and target compounds. These findings facilitate isolated toxicological investigations on organofluorophosphates that are beneficial for environmental and safety research, the battery cell industry, and human safety surveillance in regard to aged LIB electrolytes.〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Petroleum Science and Engineering, Volume 181〈/p〉 〈p〉Author(s): Shuai Zhao, Wanfen Pu, Mikhail A. Varfolomeev, Chengdong Yuan, Shan Qin, Liangliang Wang, Dmitrii A. Emelianov, Artashes A. Khachatrian〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Because the thermal release correlates directly with the success of in-situ combustion (ISC) technology, this research performs a series of investigations concerning thermal behavior and kinetics of heavy crude oil during combustion using high pressure differential scanning calorimetry (HP-DSC) and accelerating rate calorimetry (ARC). The results obtained from HP-DSC profiles indicated that for oil alone and its mixtures with quartz sand/crushed core, the peak temperature was lowered, and the heat flow increased with increasing oxygen partial pressure. The heat enthalpy of low temperature oxidation (LTO) was higher than that of high temperature oxidation (HTO) under oxygen partial pressures of 0.5, 1 and 1.5 MPa, and the increase in heat enthalpy of LTO with oxygen partial pressure was more pronounced than that of HTO. Unlike the crushed core, the addition of quartz sand delayed exothermic oxidation reactions. Compared with oil only and oil + quartz sand, the LTO and HTO peak temperatures of oil + crushed core were considerably lowered, and the effect of crushed core on increasing heat release for LTO at oxygen partial pressure of 1.5 MPa was more prominent. It was observed that the heat enthalpy of LTO and HTO increased quasi-linearly with the oxygen partial pressure in both the presence and absence of quartz sand/crushed core. ISC might be considered as an appropriate candidate for Jiqi block, based on exothermic continuity of the ARC curves, with the near-wellbore zone of target block heated to 180 °C where the exothermic oxidation activity is notably intensified. The kinetic results showed that the LTO and HTO intervals were divided into 6 and 2 subintervals, respectively, which facilitated more precise modelling of the ISC process.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Petroleum Science and Engineering, Volume 181〈/p〉 〈p〉Author(s): Zan Chen, Menglu Lin, Shuhua Wang, Shengnan Chen, Linsong Cheng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Studies have shown that the gas huff and puff injection potentially perform better than the continuous gas flooding in enhancing the hydrocarbon recovery in the liquid rich tight reservoirs. During the fracturing stimulation, only part of the induced hydraulic fractures is propped because proppants cannot be carried to the fracture tips. Moreover, some secondary and tertiary fractures may be too narrow to accommodate any proppants. The conductivity of the unpropped fractures is highly dependent on the variation of the in-situ pressure and may be open and close periodically during the huff-n-puff cycles. In this study, the stress-dependent fracture conductivity and its impact on the produced gas huff-n-puff performance are investigated in a liquid rich tight reservoir, considering the existence of the large amount of the unpropped fractures. The experimental data of stress-dependent fracture conductivity is employed first to simulate the dynamic conductivity during the depletion and the gas huff and puff cycles. A reservoir model is then constructed and history-matched based on the reservoir fluid samples and the field production data collected from the Montney liquid rich tight reservoir in Western Canada. Performance of the produced gas huff-n-puff is examined in the targeted reservoir and results show that contributions of the unpropped fractures cannot be ignored, which leads to 7.8% more condensate (i.e., oil) production and 2.8% higher in barrel of oil equivalent (BOE), compared to the case with propped fractures only. The effects of complex fracture geometry and the cluster completion are also investigated and results show that the unpropped fracture contributions towards the condensate production and BOE are even more pronounced in the complicated scenarios. The condensate oil and BOE are 42.0% and 22.9% higher in complex fracture geometry case and 12.4% and 5.6% higher in the fractures with multiple clusters than those scenarios with propped fractures only. This paper provides a better understanding on the potential performance of enhanced hydrocarbons recovery in liquid rich tight gas reservoirs via gas huff-n-puff operations.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Petroleum Science and Engineering, Volume 181〈/p〉 〈p〉Author(s): Abdelrahman Elkhateeb, Reza Rezaee, Ali Kadkhodaie〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Traditionally, prediction of facies and permeability for a reservoir rock was one of many challenges in the industry that necessitates advanced and sophisticated evaluation for effective reservoir description. Three wells have been studied in the Perth Basin in Western Australia across the shaly sand of the Irwin River Coal Measures Formation, which contain a comprehensive suite of advanced and conventional logs. Due to the reservoir heterogeneity and the clay distribution, it is very challenging to resolve the effective pore volume, the reservoir facies and how the high permeability zones are distributed within the formation.〈/p〉 〈p〉In this paper, a new technique has been successfully tested on the Shaly Sand by integrating the nuclear magnetic resonance (NMR) and the conventional density log. The method allows the establishment of high-resolution facies classification for the reservoir using an Equivalent Flow Zone Indicator Index (EFZI). The studied core facies have been integrated with the EFZI into a new workflow to distribute facies on a larger scale in the uncored wells.〈/p〉 〈p〉Four hydraulic flow units (HFU) have been defined from one cored well using Flow Zone Indicator approach, with each has a unique FZI value and different permeability model based on core measurements. The EFZI-based high-resolution facies have been validated at several formation depths using the core thin sections to ensure the best calibration will be obtained for facies log, hence the permeability log-to-core match.〈/p〉 〈p〉The methodology will help running an advanced petrophysical analysis for the zone of interest and will reduce the parameters uncertainty. Application of this methodology in the uncored wells has shown very encouraging results, which is believed it can be used in the absence of any core data to resolve the rock typing from the well logs.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Petroleum Science and Engineering, Volume 181〈/p〉 〈p〉Author(s): Atousa Heydari, Kiana Peyvandi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, the stainless steel mesh was used to study the effect of metallic porous media on the formation of methane hydrate and some parameters such as induction time, the kinetics growth and the mole of gas consumed have been investigated at a temperature of 3 °C (276.15 K) and a pressure of 760 psi (5.24Mpa). The metallic porous media was able to show better results on the methane hydrate formation relative to the silica gel. Hence the induction time and, eventually, the total time of the hydrate formation process decreased by about 60%. The kinetics growth and the amount of gas consumed increased significantly. Also, the effect of two types of anionic and nonionic surfactants as kinetics promoters studied in this porous media. The result of adding SDS and SDBS at a concentration near the CMC designated that the induction time lasted nearly zero and the total time of the process by SDBS was minimal. It should be noted that the non-ionic surfactant SPAN 80 could not have a positive effect on this porous media. In general, therefore, the results of this research attempts to show that the stainless steel mesh with SDBS possessed high potential in obtaining the industrial purpose of gas hydrate growth and also was significant in the field of energy storage and transport.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0920410519306473-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Petroleum Science and Engineering, Volume 181〈/p〉 〈p〉Author(s): Shuaishuai Jiang, Xuehua Chen, Yingkai Qi, Wei Jiang, Jie Zhang, Zhenhua He〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The frequency-dependent attenuation and velocity dispersion of seismic responses are closely related to hydrocarbon reservoirs. To further investigate the characteristics of seismic responses caused by pore fluid-bearing reservoirs, the role of gas saturation is analyzed in seismic responses of sand reservoirs characterized by the patchy saturation model. To this end, a novel wave extrapolation method is developed based on the diffusive-viscous wave equation (DVWE) as well as a scheme for an extended local Rytov Fourier (ELRF) approximation within the extrapolation depth interval. Our proposed method considers the presence of fluid mixtures in the porous media, resulting in seismic attenuation and dispersion by the mechanism generally known as wave-induced fluid flow (WIFF). This method enables an accommodation for the lateral variations in slowness, diffusion coefficient and viscosity. Subsequently, the extrapolation is adopted to model the synthetic seismic data of a distributary channel model. During this modeling, a gas-water saturated sand reservoir embedded into one of the channels was used to comparatively analyze the distinct features on its seismic synthetic data. We exhibited the numerical simulation results using the proposed wave extrapolation method here and the traditional acoustic wave equation (AWE) method. A comparison of the simulation results, demonstrates that our proposed numerical method can depict the seismic dispersion and frequency-dependent attenuation as well as the phase delay effects associated with gas-water-saturated sand reservoirs. Furthermore, we compare the seismic responses by changing the gas saturations of the sand reservoir. The gas saturation of the reservoir has significant effects on the seismic characteristics of the numerical modeling data. The numerical modeling method improves our understanding of the mechanisms of seismic frequency-dependent characteristics associated with gas saturations and potentially contributes to better insights into gas reservoir indicators derived from seismic field data.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Tetrahedron Letters, Volume 60, Issue 33〈/p〉 〈p〉Author(s): Mitali Mishra, Seetaram Mohapatra, Nilima Priyadarsini Mishra, Bighnanshu K. Jena, Pravati Panda, Sabita Nayak〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Heterocyclic compounds particularly five, six and seven membered ring containing heterocycles are the most abundant which constitute a staggeringly diverse and important class of molecules that occur ubiquitously in a variety of synthetic drugs, bioactive natural products, pharmaceuticals and agrochemicals. Owing to the glorious past and impressive present of the biologically active heterocyclic scaffolds, these skeletons have long been a subject of immense interest. Hence, substantial efforts have been made to the development of new and innovative synthetic strategies for the synthesis of these heterocycles involving use of different metal catalysts, organic and inorganic reagents etc. Among the different types of metal catalysts used, iron catalysts are one of the cheap and easily available. In recent time, several new and innovative iron(III) chloride catalyzed synthesis of heterocycles with structural diversity are coming in the forefront of the literature by the scientific community. This review highlights the advancements made so far by iron(III) chloride for the synthesis of different assemblies of small heterocycles covering the year 2014–2018.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0040403919306628-ga1.jpg" width="261" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Ocean Modelling, Volume 140〈/p〉 〈p〉Author(s): Oleg Druzhinin, Yuliya Troitskaya, Wu-ting Tsai, Po-chen Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study is concerned with direct numerical simulation (DNS) of turbulent air flow over a waved water surface. Three-dimensional, turbulent Couette flow is considered in DNS as a model of a constant-flux layer in the marine atmospheric surface layer. Two-dimensional stationary waves at the water surface are prescribed and assumed to be unaffected by the air-flow. We consider capillary-gravity water surface waves and are interested in the influence of “parasitic” capillary ripples riding on the carrier, energy-containing waves, on the properties of the air-flow. The surface waves are prescribed and considered to be stationary, the capillaries being in phase with the carrier wave. The surface elevations spectra are also prescribed and mimicking stationary capillaries riding on Stokes waves observed in a 2D numerical simulation of water-surface capillary-gravity waves by Hung & Tsai (2009). The bulk air velocity and the carrier water surface waves lengths are considered in our DNS in the range of 3 to 5 m/s and 3 to 7 cm, respectively. Under these conditions, the capillaries are found to be submerged within the viscous sublayer of the atmospheric boundary layer. Our DNS results show that although the flow fields are characterized by instantaneous separations of the boundary layer, the ensemble (wave-phase) averaged flow fields are non-separating and well predicted by a quasilinear theoretical model. We find also that capillaries mitigate the development of coherent (horse-shoe) vortex structures as compared to the no-ripples flow-case. We further use DNS results and quasilinear model formulation to parameterize the water surface roughness height in terms of critical layer thickness and the amplitude of a dominant, energy-containing harmonic of the water surface elevation spectrum.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Hiral D. Shah, J.A. Bhalodia〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this communication, we report the structural and electrical transport properties of (1-〈em〉x〈/em〉) La〈sub〉0.7〈/sub〉Sr〈sub〉0.3〈/sub〉Mn〈sub〉0.95〈/sub〉Co〈sub〉0.05〈/sub〉O〈sub〉3〈/sub〉 (LSMCO) + (〈em〉x〈/em〉) ZnO (〈em〉x〈/em〉 = 0%, 6%, 9%, 12%, 15% & 18%) composites. For the preparation of (1-〈em〉x〈/em〉) LSMCO + (〈em〉x〈/em〉) ZnO (〈em〉x〈/em〉 = 6%, 9%, 12%, 15% & 18%) composites, sample of LSMCO was prepared by the auto combustion technique/inexpensive modified sol-gel technique. The results of Rietveld refined XRD data show that LSMCO sample possesses a rhombohedral structure with the 〈em〉R-3c〈/em〉 space group whereas ZnO compound remains with hexagonal structure with the 〈em〉P6〈/em〉〈sub〉〈em〉3〈/em〉〈/sub〉〈em〉mc〈/em〉 space group in all the composite samples. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that no any extra unwanted phase was observed in each composite excluding the LSMCO and ZnO phases. ZnO is mostly distributed at the grain boundaries and on the surface of the LSMCO grains. Elemental presence and ratio was confirmed through the EDX analysis. The electrical resistivity of LSMCO and each composite was measured in the temperature range of 2 K–320 K at 0 Oe, 10 kOe, 50 kOe & 90 kOe magnetic field. The results indicate that the ZnO addition increases the resistivity of all the composites compare to that of pure LSMCO. The electrical resistivity explored by the theoretical model below 〈em〉T〈/em〉〈sub〉MI〈/sub〉 and fitting enlightenment for the observed behavior is transmitted here in detail.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Dezhi Yang, Weihua Liu, Dingfu Cheng, Jieshi Chen, Hao Lu, Chun Yu, Jijin Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉(Co, Cr)23C6 type carbide is a typical metallic compound in many cobalt bearing alloys, and it acts as the strengthening phase in the form of bulk eutectic carbides or precipitated carbides. In this work, first-principles calculations were carried out to investigate the electronic structure, phase stability, mechanical and magnetic properties of (Co, Cr)23C6 with different cobalt occupation. Some of the calculated values are compared with previous studies and, they are found to be in a good agreement. The method considering curvature radius is firstly used to describe the degree of anisotropy. The hardness calculated through elastic constants presents an approximate downtrend with the cobalt concentration. Analysis of the density of states (DOS), overlapped population and electron density maps, indicates that the bonds in (Co, Cr)23C6 are the mixture of covalent, ionic and metallic bonds, the interactions of 〈em〉d-d〈/em〉 orbits between metallic atoms contribute most to the hybridization mode. According to the population analysis, the reduction in hardness can attribute to the increase of metallicity and iconicity of the interacted metallic atoms. In addition, the formation of a large quantity of antibonding also plays a negative role in intrinsic hardness of (Co, Cr)23C6 when massive substitution of cobalt atom.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Morteza Alizadeh, Andisheh Shakery, Erfan Salahinejad〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this research, the structure and mechanical properties of 1050 aluminum strips reinforced with E-glass fibers, processed by the cross accumulative roll bonding (CARB) process, were investigated from microscopic, hardness, tensile and peeling viewpoints. The results indicated that the incorporation of the glass fibers in the Al matrix increases strength and micro-hardness but decreases elongation. In addition, it was realized that some of these fibers are broken and changed to short fibers during the CARB process. The presence of the glass fibers strongly also reduces the bond efficiency of the Al strips, typically from 50% to 5%. To compensate this deleterious effect, it was found that at least 25% should be increased to the normal thickness reduction used in CRAB.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Soil Dynamics and Earthquake Engineering, Volume 125〈/p〉 〈p〉Author(s): Ahmet Hilmi Deringöl, Esra Mete Güneyisi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study investigates the influence of the friction pendulum bearing (FPB) isolator characteristics on the nonlinear response of the buildings under various seismic excitations. To represent a wide range of assessment, 3, 6, and 9-storey steel framed buildings with twenty seven different isolation models of FPB were studied by identifying the local and global deformations. Three important parameters such as isolation period T (as 2, 2.5, and 3 s), effective damping ratio ß (as 0.05, 0.15, 0.25), and yield strength ratio Fy/W (as 0.025, 0.05, and 0.10) were used in the modelling of FPB. Two-dimensional model of the base-isolated steel frames were created and the nonlinear time history analysis was performed through a number of earthquake ground motions. The behaviour of the isolated frames was measured by the variation of isolator displacement, roof drift ratio, relative displacement, interstorey drift ratio, absolute acceleration, base shear, base moment, hysteretic curve, and dissipated energy. The benefits obtained through the adoption of the base isolation system were discussed. It was found that the seismic response of the base-isolated frames could be estimated accurately by adjusting the proper isolation period, yield strength ratio, and effective damping ratio for the case studied structures.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Soil Dynamics and Earthquake Engineering, Volume 125〈/p〉 〈p〉Author(s): Jinbao Yao, Rutao Zhao, Nan Zhang, Dujuan Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉An in-filled trench barrier is usually used to reduce the damages from train-induced environmental vibrations. To find the vibration isolation effect of an in-filled trench barrier, this paper analyses the reflection coefficients and transmission coefficients of the Rayleigh wave at the interface between in-filled trenches and the soil. In our calculation formulas of ground vibrations, a single point and a single frequency excitation, as well as multi-point and multi-frequency excitation, are simultaneously derived in a soil-in-filled-trench system.〈/p〉 〈p〉Using these formulas and a numerical analysis, the effects of an in-filled trench barrier on the environmental vibrations induced by running trains are analyzed. The results show that the reflection coefficients increase, while the transmission coefficients decrease, with the density and elastic modulus of the in-filled material. The vibration isolation effect is clearly better than that without trenches. In a certain width range, the transmission coefficient and vertical acceleration levels decrease with the increase of trench width. The influences of the transmission coefficient and the vibration isolation effects are not clear with the trenches’ depth variation. The vertical vibrations of the ground pick-up point are all smaller than those without in-filled trenches.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Soil Dynamics and Earthquake Engineering, Volume 124〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Soil Dynamics and Earthquake Engineering, Volume 125〈/p〉 〈p〉Author(s): Benshun Shao, Stephen A. Mahin, Victor Zayas〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉By interpreting the seismic responses of two seismically isolated low-rise case-study buildings probabilistically using FEMA P695 methodology, the study indicates for the design of seismically isolated structures, providing isolator capacities equal to risk-targeted maximum considered earthquake (MCE〈sub〉R〈/sub〉) demand does not achieve targeted levels of reliability specified in ASCE 7–16. To do so, isolation system capacities beyond average MCE〈sub〉R〈/sub〉 demand are required. The minimum required capacities for using three types of enhanced isolation system (isolator without displacement restraint, isolator combined with external hard-stopping mechanism, and isolator with internal stiffening behavior at large horizontal displacement) are calculated with nonlinear response history analysis following probabilistic framework for different design risk categories numerically. The results indicate that isolator displacement capacities ranging from 1.5 to 2.60 times the average MCE〈sub〉R〈/sub〉 demand and isolation system shear capacities ranging from 1.5 to 5 times the average MCE〈sub〉R〈/sub〉 demand are required, depending on seismic risk categories and isolation system types. The use of an isolator with internal stiffening behavior is an efficient option to provide the required capacities for achieving reliability goals, especially for high risk-category design.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Electrochimica Acta, Volume 319〈/p〉 〈p〉Author(s): Jeonghoon Han, Changwoo Bae, Songhwa Chae, Dukhyun Choi, Sangmin Lee, Youngsuk Nam, Choongyeop Lee〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Here we introduce the new approach to high-efficiency power generation from a salinity difference using conventional nanoporous Nafion membrane. When access areas on each side of nanoporous Nafion membrane are set to be asymmetric, the ratio of ionic current upon a voltage bias of the different polarity also becomes asymmetric, resulting in ionic diode phenomena. When this geometrical ionic diode effect is combined with a salinity gradient, it can help significantly improve the energy conversion efficiency from a salinity difference even under a hyper-saline environment with a large salinity difference, e.g. ∼41% conversion efficiency and ∼120 nW power generation with 1 M KCl and 1000-fold salinity difference, both of which are comparable with the best performances reported in the previous studies. We propose that the decrease in ion concentration polarization at a low salt concentration side is responsible for the enhanced power generation with the membrane having asymmetric access areas. Our approach is simple to implement and can be applicable to any nanoporous membrane to enhance the power generation from a salinity difference.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Electrochimica Acta, Volume 319〈/p〉 〈p〉Author(s): Jialun Chen, Ping Tong, Lingting Huang, Zhonghua Yu, Dianping Tang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉An interdigitated capacitance immunosensing system based enzymatic biocatalytic precipitation on micro-comb electrode was designed for the sensitive detection of prostate-specific antigen (PSA) by coupling Ti〈sub〉3〈/sub〉C〈sub〉2〈/sub〉 MXenes with tyramine signal amplification strategy. The immunosensor was prepared by immobilizing anti-PSA capture antibody on MXenes-coated interdigitated electrode, whereas gold nanoparticles heavily functionalized with horseradish peroxidase (HRP) and detection antibody were utilized as the signal-transducer tags. Introduction of interdigitated electrode was expected to enhance the sensitivity of capacitance immunosensor. This system mainly consisted of the sandwich-type immunoreaction, formation of tyramine-HRP repeats on gold nanoparticle and enzymatic biocatalytic precipitation. The concatenated HRP through the tyramine oxidized numerous 4-chloro-1-naphthol molecules into insoluble benzo-4-chlorohexadienone with the help of H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉, and coated the modified immunosensor to keep free ions away from the electrode, thus causing the local alteration in the capacitance. Under optimum conditions, the change of the immunosensor in the capacitance increased with the increasing target PSA concentrations from 0.1 ng mL〈sup〉−1〈/sup〉 to 50 ng mL〈sup〉−1〈/sup〉 at a detection limit of 0.031 ng mL〈sup〉−1〈/sup〉. Moreover, the interdigitated capacitance immunosensor showed good reproducibility, high specificity and acceptable accuracy for the analysis of human serum specimens in comparison with those obtained from commercial human PSA ELISA kit. Importantly, Ti〈sub〉3〈/sub〉C〈sub〉2〈/sub〉 MXenes-based interdigitated capacitance transducer open new opportunities for protein diagnostics and biosecurity.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Electrochimica Acta, Volume 319〈/p〉 〈p〉Author(s): Zhixu Jian, Honglei Li, Rui Cao, Heliang Zhou, Huaizhe Xu, Guangjin Zhao, Yalan Xing, Shichao Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Confining the dissolution and diffusion of polysulfide is considered a key factor in the realization of high-performance lithium-sulfur battery. Here, we report a polydopamine (pDA) coated sulfur-carbon composite with a unique hierarchical tower-like structure (S-HTC@pDA) for lithium sulfur cathode. The internal layer by layer structure is capable of uniformly dispersing of sulfur, providing a continuous electronic conductive path and shortening the Li〈sup〉+〈/sup〉 transport distance, while the external pDA coating can inhibit the diffusion of polysulfide. Benefited from the smart design, the S-HTC@pDA electrode achieved an excellent cycling stability, realizing a high discharge capacity of 916 mAh g〈sup〉−1〈/sup〉 at the first cycle and a capacity retention of 79.4% after 500 cycles at 1 C. Therefore, this work provides a new concept in structure design for high performance lithium sulfur cathodes.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Here, we report a polydopamine (pDA) coated sulfur-carbon composite with a unique hierarchical tower-like structure (S-HTC@pDA) for lithium sulfur cathode. The internal layer by layer structure is capable of uniformly dispersing of sulfur, providing a continuous electronic conductive path and shortening the Li〈sup〉+〈/sup〉 transport distance, while the external pDA coating can inhibit the diffusion of polysulfide.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0013468619312885-fx1.jpg" width="326" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary International〈/p〉 〈p〉Author(s): Brian F. Codding, Adrian R. Whitaker, Nathan E. Stevens〈/p〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary Science Reviews, Volume 218〈/p〉 〈p〉Author(s): Athanassios Athanassiou, Alexandra A.E. van der Geer, George A. Lyras〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The Eastern Mediterranean islands, most of which belong to the Aegean archipelago, have a complex biogeographic history, which puts its stamp on their fauna and flora. A now extinct but most important faunal component, in terms of geographic spread and taxonomic diversity, are the elephants. The Eastern Mediterranean islands are particularly rich in Pleistocene endemic elephant localities, which preserve samples of extinct endemic populations. These were either descendants of the European straight-tusked elephant 〈em〉Palaeoloxodon antiquus〈/em〉 or the Southern mammoth, 〈em〉Mammuthus meridionalis〈/em〉. Their presence, history and palaeobiogeography has been documented only for Cyprus, Crete, Kasos, Rhodes, Tilos, Kýthera, Naxos, and Delos. For six other islands only anecdotal references exist in the literature: Kálymnos, Astypálaia, Milos, Sériphos, Kýthnos and Paros. Here, we provide an update on previously published specimens and taxa, describe previously undescribed specimens that were relocated in museum collections, as well as recently excavated specimens, and put these in the context of island palaeobiogeography. We conclude that dwarf elephants, endemic to their palaeo-island, lived on the islands of palaeo-Cyclades, Astypálaia, Crete, Kasos–Kárpathos–Saría, Tilos, Rhodes and Cyprus, whereas the elephants from Kephallenía, Kálymnos and Kýthera are indistinguishable on the species level from mainland 〈em〉Palaeoloxodon antiquus〈/em〉. Elephant fossils of unresolved taxonomic status are reported from five present-day islands. The Eastern Mediterranean endemic elephants likely derived from separate and independent colonisation events from the mainland. No island supported more than one proboscidean species at any time. We found that isolation had no effect on the degree of dwarfism, but that there exists a threshold of about 6–10 km distance between the island and the mainland, below which no dwarfism evolved, likely as a result of genetic contact with the mainland population. We also found that although island area is correlated with the degree of dwarfism in elephants, other factors, such as the level of interspecific competition, may limit this degree.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary International〈/p〉 〈p〉Author(s): Xiaolin Ren, Duowen Mo, Michael Storozum, Ximena Lemoine, Yanyan Yu, Wanfa Gu, Xingshan Lei, Jiaqiang Zhang, Jianqing Lü, Tristram R. Kidder〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Archaeologists have focused on the social conditions surrounding the development of urbanism around the world, however the environmental impact of these ancient cities remains unclear. In this paper, we present palynological data from the early Bronze Age city of Dongzhao, Henan Province, China. Our data indicate that vegetation change and the development of early urban settlements are closely linked, with the advent of urban development significantly accelerating deforestation and altering the composition of local vegetation communities. The pollen record from Dongzhao provides new evidence to support the claim that urban expansion, coupled with a drying climate and the expansion of agriculture, dramatically reconfigured the landscapes of Bronze Age China.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Precambrian Research, Volume 332〈/p〉 〈p〉Author(s): Farzaneh Shakerardakani, Xian-Hua Li, Xiao-Xiao Ling, Jiao Li, Guo-Qiang Tang, Yu Liu, Behzad Monfaredi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉High-precision secondary-ion mass spectrometry (SIMS) U–Pb and Hf–O isotopic microanalyses of zircons from the central Sanandaj–Sirjan metamorphic zone (SSMZ) of the Zagros orogen, Iran, provide evidence of the presence of 2.7 Ga xenocrystic zircons, suggesting that the SSMZ records Neoarchean crustal components that have not previously been reported in Iran. The two amphibolite samples analyzed from the Muteh–Golpaygan metamorphic complex during this study include one sample (GQ-10) that yielded xenocrystic zircons with ages clustered around 〈em〉ca〈/em〉 2.7 Ga. The second sample (GC-15) contains zircons that show two distinct xenocrystic zircon domains with ages of (i) 〈em〉ca〈/em〉 2.7 and 2.5 Ga, and (ii) 〈em〉ca〈/em〉 52 Ma. The 〈em〉ca〈/em〉 2.7 Ga zircons and zircon domains have homogeneous, mantle-like δ〈sup〉18〈/sup〉O values with a mean of 6.10 ± 0.69‰. They have εHf(t) values that vary between +0.2 to +6.8 with T〈sub〉DM〈/sub〉〈sup〉C〈/sup〉 ages of 3.1–2.7 Ga, suggesting they crystallized from granitoid melts derived from juvenile components. However, the younger 〈em〉ca〈/em〉 2.5 Ga zircons yield an average δ〈sup〉18〈/sup〉O value of 6.17 ± 0.24‰ and have evolved Hf isotopic compositions (εHf(t) −0.8 to −3.4; T〈sub〉DM〈/sub〉〈sup〉C〈/sup〉 = 3.2–3.1 Ga), indicating that the older crust in this region underwent more intense later reworking than is the case for crustal material formed at 〈em〉ca〈/em〉 2.7 Ga. These data provide evidence of Neoarchean basement rocks in this region, indicating that the SSMZ records ancient crustal growth events. The youngest 〈em〉ca〈/em〉 52 Ma xenocrystic zircons within these samples most likely reflect the late Paleocene–Eocene magmatic ‘flare-up’ within Iran. These zircons have slightly elevated δ〈sup〉18〈/sup〉O values (7.69 ± 0.21‰) and negative Hf isotopic compositions (εHf(t) −8.3 to −12.1; T〈sub〉DM〈/sub〉〈sup〉C〈/sup〉 = 1.9–1.6 Ga), suggesting intensive crustal reworking at 〈em〉ca〈/em〉 50 Ma.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Precambrian Research, Volume 332〈/p〉 〈p〉Author(s): Kelsey G. Lamothe, Paul F. Hoffman, J. Wilder Greenman, Galen P. Halverson〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The Islay carbon isotope anomaly is a late Tonian negative δ〈sup〉13〈/sup〉C excursion that has been documented in marine carbonates globally. It has in the past been thought to be causally linked to the onset of Cryogenian glaciation ca. 717 Ma. However, recent work suggests that this anomaly is instead closer to ca. 739–735 Ma and that it may be one of two distinct late Tonian carbon isotope anomalies. Here we present the litho- and chemo-stratigraphy of the late Tonian Ugab Subgroup of the Otavi/Swakop Group in northwestern Namibia. Carbon isotope data from two separate outcrop belts, the Summas Mountains and the Vrede Domes, indicate that the Ugab Subgroup strata exposed in the former inlier are older than those of the latter, with only approximately 100 m of stratigraphic overlap. We use detailed measured sections to develop a sequence stratigraphic framework for the Ugab Subgroup in each outcrop belt, and correlate strata across the two exposures to construct a composite carbonate δ〈sup〉13〈/sup〉C record for the late Tonian in Namibia. This carbon isotope profile of the Ugab Subgroup shows two separate pre-Sturtian negative anomalies, consistent with findings in northern Canada, Svalbard, Scotland, and Ethiopia. Our results are an important contribution to the pre-Cryogenian carbon isotope record, as these data may serve as the first definitive documentation of both anomalies within a single basin.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Precambrian Research, Volume 332〈/p〉 〈p〉Author(s): V.S. Shatsky, Q. Wang, S.Yu. Skuzovatov, A.L. Ragozin〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉To clarify the tectonic-thermal evolution of the Anabar tectonic province in the central Siberian Craton, we performed an isotope-geochemical study of 20 xenoliths from the Udachnaya, Zarnitsa, and Komsomolskaya kimberlite pipes to represent different crustal levels. Most mafic granulites have Proterozoic Nd model ages and geochemical characteristics close to those of intraplate basalts, whereas some mafic and intermediate granulites with Archean model ages exhibit geochemical features of supra-subduction ophiolitic basalts. Analysis of U-Pb ages and hafnium isotopic composition of zircon indicates that the main tectonic-thermal events modified the crust at 2.7 and 1.9–1.8 Ga, which is consistent with ages of mantle depletion events from previous studies. All zircons have Archean Hf model ages (〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.svg"〉〈mrow〉〈msubsup〉〈mi〉T〈/mi〉〈mrow〉〈mi mathvariant="italic"〉DM〈/mi〉〈/mrow〉〈mi〉C〈/mi〉〈/msubsup〉〈mspace width=".25em"〉〈/mspace〉〈mn〉3.6〈/mn〉〈mo linebreak="badbreak" linebreakstyle="after"〉-〈/mo〉〈/mrow〉〈/math〉3.2 Ga). Overall, thermal events with ages of 2.9–2.8, 2.7, 2.4, 1.97 and 1.8 Ga have remarkable influence on the studied zircons. Tectono-thermal events at 2.4 1.97, 1.9 and 1.8 Ga with no addition of juvenile material are recorded by zircons from xenoliths of mafic and intermediate granulites and metadiorites. A compilation of isotope-geochemical data demonstrates that instead of age-stratified, the crust of the Anabar tectonic province consists of variably reworked Paleoarchean rocks and juvenile Proterozoic rocks at all crustal levels. Hence the crust and mantle of the Siberian Craton has been coupled since the Paleoarchean.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Precambrian Research〈/p〉 〈p〉Author(s): B.R. Choudhary, R.E. Ernst, Y-G. Xu, D.A.D. Evans, M. de Kock, J.G. Meert, A. Ruiz, G.A. Lima〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉1110 Ma Large Igneous Province (LIP) fragments in the Kalahari craton, southern Africa (Umkondo LIP); Dronning Maud Land, Antarctica; Bundelkhand portion of Indian craton (Mahoba dolerite dykes); Congo craton (Huila-Epembe dolerite dykes); and Amazonia (Rincon del Tigre-Huanchaca LIP) have been reconstructed as a single LIP with plume centre beneath the NW part of the Kalahari Craton. This paper offers the best estimates for the paleoposition of the〈/p〉 〈p〉Indian and Amazonian cratons along with conjoined Kalahari-SF/Congo reconstruction. This 1110 Ma mafic magmatism is dominantly tholeiitic, ranging from basalt to andesitic basalt in composition, generated over a range of mantle melting depths [(Gd/Yb)N =1.2 to 2.3], exhibit low to high contamination with crustal components (negative Nb anomalies, eNd (0 to -12), and elevated Th/Yb). The data fall into two Groups based on TiO2 content, with Group 1 (low Ti) of andesitic basalt composition, and Group 2 (high Ti) exhibiting a basaltic affinity. Group 1 magmas were generated in the spinel lherzolite field followed by significant contamination likely during passage through metasomatised lithospheric mantle in crustal magma chambers. A greater melting depth reaching into the garnet lherzolite field is proposed for the Group 2 magmas. The majority of Group 2 units are located in the Kalahari and Congo cratons, and this reflects onset of deeper melting closer to the interpreted plume axis in our reconstruction.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Computers & Geosciences, Volume 132〈/p〉 〈p〉Author(s): T. Carlotto, P.L.B. Chaffe〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Streamflow recession analysis is crucial for understanding how catchments release water in periods of drought and therefore is important for water resources planning and management. Despite there being several theories on how to model recession curves, few studies compare the different approaches to that problem. In this work, we developed the Master Recession Curve Parameterization tool (MRCPtool), which brings together a set of automated methods for the analysis of recession periods based only on streamflow data. The methods include: (i) hydrograph separation using numerical filters; (ii) automatic extraction of recession periods; (iii) creation of the MRC with the matching strip method; (iv) creation of the MRC for different flow classes defined from the flow duration curve; (v) analysis of flow recession rates 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" altimg="si1.svg"〉〈mrow〉〈mo〉(〈/mo〉〈mo linebreak="goodbreak" linebreakstyle="after"〉−〈/mo〉〈mi〉d〈/mi〉〈mi〉Q〈/mi〉〈mo〉∕〈/mo〉〈mi〉d〈/mi〉〈mi〉t〈/mi〉〈mo〉)〈/mo〉〈/mrow〉〈/math〉 as a function of flow 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" altimg="si2.svg"〉〈mrow〉〈mo〉(〈/mo〉〈mi〉Q〈/mi〉〈mo〉)〈/mo〉〈/mrow〉〈/math〉 and (vi) creation of the MRC from simulated recession curves with different analytical approaches, including linear and nonlinear models. The MRCPtool contains a graphical user interface developed in MATLAB software that facilitates the analysis of streamflow datasets. Finally, we present an example application of the MRCPtool using a streamflow dataset of 44 years. The MRCPtool is an open source tool that can be downloaded from the site: 〈a href="http://www.labhidro.ufsc.br/static/software/MRCPtool.rar" target="_blank"〉http://www.labhidro.ufsc.br/static/software/MRCPtool.rar〈/a〉.〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Precambrian Research〈/p〉 〈p〉Author(s): Vladimir N. Sergeev, J. William Schopf, Anatoliy B. Kudryavtsev〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Subtidal cherts from phosphorite-bearing basal strata of the Early Cambrian Shabakta (Dzhylandy) Formation, Tamda Group of the Maly Karatau Range of South Kazakhstan, contain a diverse assemblage of acanthomorph acritarchs and other well-preserved organic-walled microfossils. Acanthomorphs of the Shabakta lowermost layers are taxonomically essentially identical to those of many similarly aged Early Cambrian organic-walled compression-preserved and permineralized microbiotas preserved in rocks deposited in relatively open marine settings and are biostratigraphically correlative with acanthomorph-containing microfloral assemblages of the Vergale and Rausve Horizons (Regional Stages) of the East European Platform as well as with other assemblages known worldwide from the upper Atdabanian (Series 2 of the International Union of Geological Sciences [IUGS]). Although lower Atdabanian deposits of the Talsy (Lükati) horizon are missing from the Maly Karatau succession studied here, Nemakit-Daldynian through Tommotian (the IUGS Terranovian) microbiotas both of the Shabakta-underlying Berkuta Member of the Kyrshabakta Formation and phosphoritic Chulaktau Formation are comparable to those of the pre-trilobite Rovno and Lontova Horizons (Regional Stages) of the East European Platform. Thus, the phosphatized and chert-permineralized Shabakta assemblages date from of the Early Cambrian part of the Precambrian-Cambrian phosphogenic event, an interpretation supported also by associated small shelly fossils.〈/p〉 〈p〉The studies reported here of the Shabakta microfossils – based on the use of optical microscopy, confocal laser scanning microscopy (CLSM) and Raman spectroscopy – provide information in three dimensions at high spatial resolution about their organismal morphology, cellular anatomy, kerogenous composition, taphonomy, and mode and fidelity of preservation. The combined use of CLSM and Raman, techniques introduced to Precambrian paleobiology only rather recently, is shown to reveal morphological characters of taxonomic, biostratigraphic and palaeoenvironmental significance.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0301926818306260-ga1.jpg" width="274" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Marine and Petroleum Geology, Volume 110〈/p〉 〈p〉Author(s): Walid A. Makled, Ahmed A. Abd El Ghany, Soheir I. Soliman〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Productivity, redox conditions and sedimentation rate constrain the enrichments of organic matters and under suitable conditions they can trigger larger enrichments. These parameters are tracked in the subsurface Miocene sediments in four wells on east to west transect across north Sinai. These wells are Abu Roda-1, Misfaq-1, Teffah-1 and Einab-1. The Miocene sections cover the Aquitanian, Burdigalian, Langhian, Serravalian and Tortonian. The tracking is based on the proxies of planktonic and benthic foraminifera that offer many solutions in the application of the equations used to calculate these parameters. The first of these parameters is the sedimentation rate which is calculated for different time segments based on the planktonic foraminifera bioevents. The sedimentation rates are correlated throughout the basin. The second parameter is the water depth that is obtained from conversion of the scores of component 1 resulted during the routine statistical analysis of the benthic foraminifera by cluster and principal component analyses. These analyses are used also in assessment of redox condition and eutrophication. The sedimentation rates and water paleobathymetry alongside the measured C〈sub〉org〈/sub〉 are used to calculate the paleoproductivity and to determine four stratigraphic sequences (Seq1, Seq2, Seq3 and Seq4). The tracking of these parameters reveal higher productivity levels in the Seq1 (Aquitanian and Burdigalian) accompanied with dysoxic and mesotrophic conditions, however the lower sedimentation rates are not optimum to stimulate enough burial efficiency that reduced values of C〈sub〉org〈/sub〉. In the younger sequences (Seq2-4), the higher sedimentation rates increase the burial efficiency and values of C〈sub〉org〈/sub〉 despite the lower paleoproductivity and oxic oligotrphic conditions.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Marine and Petroleum Geology, Volume 110〈/p〉 〈p〉Author(s): Marwa Yousef, Mohamed Yousef, Adel Sehim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉High-quality three-dimensional (3D) seismic reflection and borehole data are used to characterize in detail the structural style and evolution of inversion structures in Horus oil field. This field lies in the central part of Alamein Basin, northern Western Desert of Egypt, in the hanging-wall of a major Jurassic-Early Cretaceous normal fault. This fault delineates the northwestern margin of the basin and extends in an ENE-WSW direction, bounding a half-graben trough in its hanging-wall. This trough had continued subsidence during Early Cretaceous time with depositional thickening of the Lower Cretaceous Alam el Bueib Formation. Fault displacement had ceased near the top of Barremian level. Aptian-Lower Senonian seismically traced levels show a major NE-plunging asymmetrical anticline overlying the Jurassic-Barremian half-graben. This anticline is sub-parallel to the inherited Jurassic rifting fault. At shallower Cretaceous levels, this fault is replaced by a set of WNW-ESE-trending en echelon faults of considerable displacements, which probably indicates a strike-slip component of deformation. These faults display normal separation on all displaced stratigraphic levels and tip upwards in the upper part of the Upper Cretaceous succession. This marks a considerable change in the tectonic mode of the area. NW-SE extensional faults were developed perpendicular to the fold axis, dissecting the anticline into several blocks entrapping hydrocarbons. Detailed seismic structural analysis of growth strata indicates that the fold initiated in Early Senonian time was associated with the inversion of the earlier Jurassic-Barremian half-graben. This basin inversion is attributed to the Syrian-Arc event that dominated North Africa during the Late Cretaceous time and continued through to the Early Miocene. Low fold amplitude coupled with normal displacements on the deep-seated ENE-WSW-trending Jurassic-Barremian fault indicate a mild phase of positive inversion. The Upper Senonian-Eocene stratigraphic sequences increased in thickness in the back-troughs that were associated with basin inversion.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0264817219303198-fx1.jpg" width="57" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Geoderma, Volume 353〈/p〉 〈p〉Author(s): Jingzhe Wang, Jianli Ding, Danlin Yu, Xuankai Ma, Zipeng Zhang, Xiangyu Ge, Dexiong Teng, Xiaohang Li, Jing Liang, Ivan Lizaga, Xiangyue Chen, Lin Yuan, Yahui Guo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Soil salinization is one of the most important causes for land degradation and desertification and is an important threat to land management, farming activities, water quality, and sustainable development in arid and semi-arid areas. Soil salinization is often characterized with significant spatiotemporal dynamics. The salt-affected soil is predominant in the Ebinur Lake region in the Northwestern China. However, detailed local soil salinity information is ambiguous at the best due to limited monitoring techniques. Nowadays, the availability of Multi-Spectral Instrument (MSI) onboard Sentinel-2, offers unprecedented perspectives for the monitoring and mapping of soil salinity. The use of MSI data is an innovative attempt for salinity detection in arid land. We hypothesize that field observations and MSI data and MSI data-derived spectral indices using the partial least square regression (PLSR) approach will yield fairly accurate regional salinity map. Based on electrical conductivity of 1:5 soil:water extract (EC) of 72 ground-truth measurements (out of 116 sample sites) and various spectral parameters, such as satellite band reflectance, published satellite salinity indices, red-edge indices, newly constructed two-band indices, and three-band indices from MSI data, we built a few inversion models in an attempt to produce the regional salinity maps. Different algorithms including Pearson correlation coefficient method (PCC), variable importance in projection (VIP), Gray relational analysis (GRA), and random forest (RF) were applied for variable selection. The results suggest that both the newly proposed normalized difference index (NDI) [(B12 − B7) / (B12 + B7)] and three-band index (TBI4) [(B12 − B3) / (B3 − B11)] show a better correlation with validation data and could be applied to estimate the soil salinity in the Ebinur Lake region. The established models were validated using the remaining 44 independent ground-based measurements. The RF-PLSR model performed the best across the five models with R〈sup〉2〈/sup〉〈sub〉V〈/sub〉, RMSE〈sub〉V〈/sub〉, and RPD of 0.92, 7.58 dS m〈sup〉−1〈/sup〉, and 2.36, respectively. The result from this model was then used to map the soil salinity over the study area. Our analyses suggest that soil salinization changes quite significantly in different seasons. Specifically, soil salinity in the dry season was higher than in the wet season, mostly in the lake area and nearby shores. We contend that the results from the study will be useful for soil salinization monitoring and land reclamation in arid or semi-arid regions outside the current study area.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Marine and Petroleum Geology, Volume 110〈/p〉 〈p〉Author(s): Shuheng Du, Yapu Zhao, Jun Jin, Gen Kou, Yongmin Shi, Xianfu Huang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Perthite is a special type of skeleton mineral in tight oil sandstone which cannot be ignored. However, few attention was paid to the secondary pores in perthite and their contributions in tight oil reservoir. This study reveals the perthite's significance in unconventional oil flow characterizes comprehensively and quantitativel by combining the Field Emission Scanning Electron Microscope (FE-SEM) with high resolution, Energy Dispersive Spectrometer (EDS) analysis, high precision image processing, comprehensive parameters construction and calculation. Typical perthite samples of Chang 7 tight oil reservoir of Ordos basin were selected for this study. Our results demonstrate that the growth of K-feldspar and Na-feldspar in perthite is complementary. The mixing process of the two types of stripes promotes each other rather than inhibiting each other. As to the development of secondary pores of perthite, there are clear differences in the area and number of pores, medium differences in the porosity, radius and perimeter, and small differences in other parameters. The more regular and uniform growth of Na-feldspar, the more likely the perthite is to form regular and normalized secondary pore. At least 56.7% of the secondary pore of perthite contributes to oil flow in the process of oil migration or development, and its scientific significance cannot be ignored. The conclusion could provide the geological basis for the effective development of the unconventional hydrocarbon reservoirs.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 9 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Geochemistry〈/p〉 〈p〉Author(s): Yu Zhang, Xianghong Meng, Duoyun Wang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The Ordos Basin is a large interior continental sedimentary basin in western China； its Mesozoic evolution was controlled by surrounding orogenic belts. To constrain the evolution of the southern Ordos Basin, four samples from the southern Ordos Basin were analyzed for U-Pb ages. Similar detrital zircon U-Pb age patterns of the samples suggest no provenance change occurred during the Middle Triassic. Detrital zircons from the samples are divided into three major groups based on their U-Pb ages: 360-250 Ma, 2000-1600 Ma and 2800-2200 Ma. The first group of zircons is consistent with Paleozoic igneous zircons from the northern margin of the North China Craton (NCC). Detrital zircons of the second and third groups are likely derived from the basement of the NCC northern margin. In the Middle Triassic, detritus from the Qinling Orogenic belt may only have reached the piedmont deep depression. The absence of the Qilian Mountain source suggests that the Ordos Basin may not have been connected with the Hexi Corridor Basin in the Middle Triassic. Combining our results with those of previous studies, we suggest that the southern borderline of the Ordos Basin may not have reached the Qinling Orogenic Belt. The northern margin of the NCC, the Qinling Orogenic Belt and the pre-Middle Triassic sedimentary rocks of the eastern NCC provided sources for the Southern Ordos Basin in the Late Triassic. The rapid uplift of the Qinling Orogenic belt occurred in the Late Triassic. This event was response to collision between the NCC and the South China Block. The deposition and evolution of the Ordos Basin were controlled by the Indosinian movement. The change in source areas for the Southern Ordos Basin was closely related to the development and evolution of the Qinling Orogenic Belt. The Qinling Orogenic Belt shows good coupling with the sedimentation and structures of the Southern Ordos Basin.〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Applied Geophysics, Volume 169〈/p〉 〈p〉Author(s): Zhiqu Lu, Glenn V. Wilson, Mark W. Shankle〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉For soil exploration in the vadose zone, a high-frequency multi-channel analysis of surface waves (HF-MASW) method with three enhanced techniques has been developed. In this paper, we apply this enhanced HF-MASW method to re-process field testing data that were collected over the past several years on five different sites. These sites are selected for their different soil properties and data acquisition configurations. The derived overtone images, extracted dispersion curves, and inverted soil profiles of these soil sites are shown and discussed. Penetration tests were conducted and comparisons are made between the soil profiles taken from the HF-MASW tests and those from the penetration tests. One of the objectives of the paper is to determine the optimal data acquisition parameters, including the source parameters and sensor array geometric configuration through the discussions of these case studies. Practical concerns of the HF-MASW method and lessons learnt from these tests are addressed. Recommendations for data acquisition, signal processing, and inversion are provided.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Free Radical Biology and Medicine, Volume 141〈/p〉 〈p〉Author(s): Chao Wang, Yuan Yuan, Jie Wu, Yuanlin Zhao, Xing Gao, Yihua Chen, Chao Sun, Liming Xiao, Pengfei Zheng, Peizhen Hu, Zengshan Li, Zhe Wang, Jing Ye, Lijun Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉While cardiac hypertrophy and heart failure are accompanied by significant alterations in energy metabolism, more than 50–70% of energy is obtained from fatty acid β-oxidation (FAO) in adult hearts under physiological conditions. Plin5 is involved in the metabolism of lipid droplets (LDs) and is highly abundant in oxidative tissues including heart, liver and skeletal muscle. Plin5 protects the storage of triglyceride (TG) in LDs by inhibiting lipolysis, thereby suppressing excess FAO and preventing excessive oxidative stress in the heart. In this study, we investigated the roles of Plin5 in cardiac hypertrophy and heart failure in mice treated with transverse aortic constriction (TAC). The results indicated that Plin5 deficiency aggravated myocardial hypertrophy in the TAC-treated mice and exacerbated the TAC-induced heart failure. We also found that Plin5 deficiency reduced the cardiac lipid accumulation and upregulated the levels of PPARα and PGC-1α, which stimulate mitochondrial proliferation. Moreover, Plin5 deficiency aggravated the TAC-induced oxidative stress. We consistently found that Plin5 knockdown disrupted TG storage and elevated FAO and lipolysis in H9C2 rat cardiomyocytes. In addition, Plin5 knockdown also provoked mitochondrial proliferation and lipotoxic injury in H9C2 cells. In conclusion, Plin5 deficiency increases myocardial lipolysis, elevates FAO and oxidative burden, and thereby exacerbates cardiac hypertrophy and heart failure in TAC-treated mice.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S089158491930471X-fx1.jpg" width="336" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: Cover illustration The Wawel Dragon above Krakow. Illustration by Apolonia Stankiewicz originally published in page 3 of Baïka magazine, issue n°14, March 2019.

Description: Tonicity‐responsive enhancer binding protein (TonEBP) is a widely expressed transcription factor and is important in the regulation of inflammatory cytokines. Here, we have identified TonEBP expression in the hypothalamus, which is particularly high in proopiomelanocortin (POMC) neurons. TonEBP overexpression stimulates POMC transcription, and TonEBP haploinsufficiency in TonEBP (+/−) mice results in a decrease in hypothalamic POMC expression. TonEBP (+/−) mice show reduced sickness responses, which include anorexia and hyperthermia, that are initially induced by tumor necrosis factor (TNF)‐α. TonEBP (+/−) mice also show lower levels of TNF‐α‐induced hypothalamic expression of POMC and pro‐inflammatory cytokines. These results suggest that TonEBP is an important molecular regulator in the development of inflammatory sickness responses through the control of POMC and pro‐inflammatory cytokine expression in the hypothalamus.

Description: 〈p〉Publication date: 15 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Lithos, Volumes 346–347〈/p〉 〈p〉Author(s): Rohit Pandey, Ashutosh Pandey, N.V. Chalapathi Rao, B. Belyatsky, A.K. Choudhary, B. Lehmann, Dinesh Pandit, Prashant Dhote〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We present petrology, geochemistry and radiogenic isotope (Sr and Nd) data of thirteen post-Deccan lamprophyre dykes in the Narmada rift zone from the Chhotaudepur alkaline province of the Deccan Large Igneous Province (DLIP). Mineralogically, these dykes show affinity towards alkaline (sannaite and camptonite) as well as ultramafic (damtjernite) varieties of lamprophyres. Their major oxides and certain trace element ratios increase with increasing silica content highlighting the strong influence of fractionation processes. Their Nb/U and Ce/Pb ratios are similar to the mantle array defined by MORBs and OIBs and suggests an uncontaminated nature. Major oxide (K〈sub〉2〈/sub〉O, Na〈sub〉2〈/sub〉O, SiO〈sub〉2〈/sub〉 and TiO〈sub〉2〈/sub〉) contents show geochemical similarity towards shoshonitic volcanic series, whereas elevated Zr/Hf and Nb/La coupled with suppressed Rb/Nb and Zr/b display their affinity towards HIMU-type intraplate basalts. Their radiogenic initial 〈sup〉87〈/sup〉Sr/〈sup〉86〈/sup〉Sr (0.706034–0.710582) and sub-chondritic initial ɛNd (−8.6 to 2.1) are akin to those of the (i) ca. 65 Ma Ambadongar carbonatite, NW India, and (ii) ca. 65 Ma orangeites from Bastar Craton, central India, highlighting an enriched lithospheric mantle source. REE inversion modeling suggests ~3% enrichment of an undepleted mantle followed by small degrees of melting of this enriched mantle source are sufficient- as in the case of ocean island basalts (OIB)- to reproduce their observed REE concentrations. Their T〈sub〉DM〈/sub〉 Nd model ages (564–961 Ma) are consistent with widespread convergent margin-related magmatism during the amalgamation of the Rodinia supercontinent. We propose that enriched lithospheric mantle developed during the Neoproterozoic was metasomatized by small-volume CO〈sub〉2〈/sub〉-rich melts imparting a HIMU-type geochemical character during Late Cretaceous, when the mantle plume (viz., Réunion) responsible for the flood basalt eruption, impinged at the base of the NW Indian lithosphere. From the presence of F-rich apatite and high K/Rb in mica, we infer the (i) presence of F-phlogopite in their source regions, and (ii) that the depth of post-Deccan lithosphere-asthenosphere boundary (LAB) beneath NW India was at least ~100 km at ca. 65 Ma.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Lithos, Volumes 346–347〈/p〉 〈p〉Author(s): Babita Rani Choudhary, M. Santosh, Benedetto De Vivo, Gajananrao Jadhav, E.V.S.S.K. Babu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Silicate melt inclusions (MI) trapped in minerals provide direct tools to evaluate source characteristics and magma evolution including magma chamber processes. Here we present results from the study of MIs in basalts from the Western Ghats region of the Deccan Large Igneous Province (LIP) in India. The MIs in plagioclase and clinopyroxene phenocrysts were analyzed. The MIs exhibit post-entrapment modification by in situ crystal fractionation, chemical interaction with the host phenocryst (plagioclase or clinopyroxene), degassing/decrepitation, and crystallization of daughter minerals during cooling. The MIs display variable silica (SiO〈sub〉2〈/sub〉 41–68 wt%), low potassium, and high Fe〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉Ti contents, corresponding to differentiation of basaltic to andesitic magma. Our data indicate H〈sub〉2〈/sub〉O content of about 2 wt% which is consistent with recent evidence for elevated primary H〈sub〉2〈/sub〉O content in the Deccan and other LIPs, corresponding to elevated H〈sub〉2〈/sub〉O in the lithospheric mantle and plumes passing through the mid-mantle inheriting the hydrous nature.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Crystal Growth, Volume 523〈/p〉 〈p〉Author(s): Yuichiro Hayashi, Takeshi Mitani, Naoyoshi Komatsu, Tomohisa Kato, Hajime Okumura〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We investigated the surface roughening in 4H-SiC solution growth from the following two aspects: the roughening of the seed surface before seeding and the roughening caused by the adhesion of SiC particles during growth. First, we investigated the morphological changes of the seed surface before and after the melt-back process. The seed surface just before seeding was covered with macrosteps and 6H-SiC hillocks with a height of several micrometers. This surface roughening was caused by condensation of droplets of vaporized solvent on the seed surface. We found that the 6H-SiC hillocks were the origins of trench defects. The melt-back process completely removed the hillocks and produced a smooth surface adequate for successive bulk growth. Second, we investigated surface roughening caused by the formation of SiC particles. The adhesion of SiC particles on the growth surface introduced trench defects and polytype inclusions. The adhesion of SiC particles was suppressed by controlling the distribution of carbon supersaturation in the solvent.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Lithos, Volumes 346–347〈/p〉 〈p〉Author(s): Rosana Silveira Resende, Carlos Alberto Tello Sáenz, Luiz Augusto Stuani Pereira, Elton Luiz Dantas〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Understanding the chemical etching effects in the crystalline structure of zircon grains is crucial to know their chemical composition, morphology and isotopic geochemistry. After chemical etching, the zircon grain can be classified as homogeneous heterogeneous, hybrid and anomalous depending on the surface fission-track density observed under an optical microscope. The complementary techniques such as optical microscopy, micro-Raman spectroscopy, scanning electron microscopy (imaging by cathodoluminescence and secondary electrons) and electron microprobe, were employed to characterize the zircon grain surfaces from Igneous, Metamorphic and Sedimentary rocks before and after chemical etching, except for Raman spectroscopy. Measurements of U-Pb age are concordant in areas on the grain surface with uniform fission-track density. The chemical and isotopic analyses show that the etching is capable of revealing the different layer imperfections of the zircon crystalline structure, which can be inherent in its crystallization or acquired during its geological history. Therefore, identification of crystallographic preserved areas on the zircon surface, which are associated with uniform fission-track density, helps to get highly concordant U-Pb ages. In general, the results showed that the U-Pb system depends significantly on the amorphization degree of the zircon crystalline structure, which in most cases can only be revealed by etching.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Applied Geophysics, Volume 169〈/p〉 〈p〉Author(s): Rakoto Heritiana A., Rajaomahefasoa Riva, Razafiarisera Ralay, Razafindrakoto Boni〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Multiple electrical geophysical survey techniques were used to evaluate the flaky graphite reserves found along the east coast of Madagascar. Self-potential (SP) combined with induced polarization (IP) and electrical resistivity tomography (ERT) methods were applied and provide information about the graphite ore spatial distribution. Unlike conventional geophysical survey methods that use SP and electromagnetic (EM) methods for exploration of this type of metal, the addition of IP and ERT offers a geoelectrical map and section which indicate correlations with the graphite content.〈/p〉 〈p〉The obtained SP map enabled us to delineate the mineralized area whereas the geoelectrical sections obtained from ERT and IP provide additional information on the vertical extent of the mineral of interest, in this case flake-graphite. We overlaid the graphite content, as measured on samples, on the SP map in order to verify the effectiveness of the geophysical methodology. Good correlation between negative SP anomalies and positive indication of graphite content confirms that the methods used in this study (SP, ERT and IP) are sensitive for delineation of the mineralized zone and consequent evaluation of the ore reserve. Resistivity and chargeability obtained from the inversion of the ERT/IP data are low and high, respectively, within the saturated zone inside SP-anomalous zones.〈/p〉 〈p〉The principal ore body is located in the lateritic zone composed of clay-rich formations derived from the weathering of gneiss and migmatite rocks. Negative SP anomalies, along with low electrical resistivity and high chargeability values, are found mainly in areas where the graphitic content exceeds 5%.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms, Volume 1862, Issue 8〈/p〉 〈p〉Author(s): Ruifan Wu, Guanqun Guo, Zhen Bi, Youhua Liu, Yuanling Zhao, Nana Chen, Fengqin Wang, Yizhen Wang, Xinxia Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉〈em〉N〈/em〉〈sup〉6〈/sup〉-methyladenosine (m〈sup〉6〈/sup〉A), the most abundant internal mRNA modification in eukaryotes, plays a vital role in regulating adipogenesis. However, its underlying mechanism remains largely unknown. Here, we reveal that deletion of m〈sup〉6〈/sup〉A demethylase FTO in porcine and mouse preadipocytes inhibits adipogenesis through JAK2-STAT3-C/EBPβ signaling. Mechanistically, FTO deficiency suppresses JAK2 expression and STAT3 phosphorylation, leading to attenuated transcription of C/EBPβ, which is essential for the early stage of adipocyte differentiation. Using dual-luciferase assay, we validate that knockdown of FTO reduces expression of JAK2 in an m〈sup〉6〈/sup〉A-dependent manner. Furthermore, we find that m〈sup〉6〈/sup〉A “reader” protein YTHDF2 directly targets m〈sup〉6〈/sup〉A-modified transcripts of JAK2 and accelerates mRNA decay, which results in decreased JAK2 expression and inactivated JAK2-STAT3-C/EBPβ signaling, thereby inhibiting adipogenesis. Collectively, our results provide a novel insight into the molecular mechanism of m〈sup〉6〈/sup〉A methylation in post-transcriptional regulation of JAK2-STAT3-C/EBPβ signaling axis and highlight the crucial role of m〈sup〉6〈/sup〉A modification and its modulators in adipogenesis.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1861, Issue 8〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, Volume 1865, Issue 10〈/p〉 〈p〉Author(s): Tomonaga Ichikawa, Shingo Nakahata, Masahiro Fujii, Hidekatsu Iha, Kazuya Shimoda, Kazuhiro Morishita〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉N-myc downstream-regulated gene 2 (NDRG2) is a candidate tumor suppressor that is frequently downregulated in adult T-cell leukemia/lymphoma (ATLL) and functions to negatively regulate several cellular signaling pathways as PP2A recruiter. To clarify the molecular mechanisms of suppression of NDRG2 expression, we initially determined the expression pattern of NDRG2 in various types of T-cells and ATLL cells. NDRG2 expression was significantly upregulated in HTLV-1/Tax-immortalized T-cells, which was mediated by NF-κB activation through Tax expression. On the other hand, NDRG2 expression was suppressed in HTLV-1-infected cell lines and various types of ATLL cells, which was dependent on the DNA methylation of the NDRG2 promoter. We found that the expression of enhancer of zeste homolog 2 (EZH2), a member of the polycomb family, is increased in ATLL, and that EZH2 directly binds to the NDRG2 promoter and induces DNA methylation of the NDRG2 promoter. Since the expression of EZH2 were anti-parallelly regulated with the NDRG2 expression, EZH2 might be one of the most important regulators of the downregulation of NDRG2, contributing to enhanced activation of signaling pathways during ATLL development.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1861, Issue 9〈/p〉 〈p〉Author(s): Mariafrancesca Scalise, Michele Galluccio, Lorena Pochini, Jessica Cosco, Miriam Trotta, Manuele Rebsamen, Giulio Superti-Furga, Cesare Indiveri〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The lysosomal amino acid transporter SLC38A9 is referred to as transceptor, i.e. a transporter with a receptor function. The protein is responsible for coupling amino acid transport across the lysosomal membrane according to the substrate availability to mTORC1 signal transduction. This process allows cells to sense amino acid level responding to growth stimuli in physiological and pathological conditions triggering mTOR regulation. The main substrates underlying this function are glutamine and arginine. The functional and kinetic characterization of glutamine and arginine transport was performed using human SLC38A9 produced in 〈em〉E. coli〈/em〉, purified by affinity chromatography and reconstituted in liposomes. A cooperative behaviour for the wild type protein was revealed for both the substrates. A novel Na〈sup〉+〈/sup〉 binding site, namely T453, was described by combined approaches of bioinformatics, site-directed mutagenesis and transport assay. Stimulation by cholesterol of glutamine and arginine transport was observed. The biological function of SLC38A9 relies on the interaction between its N-terminus and components of the mTOR complex; a deletion mutant of the N-terminus tail was produced and transport of glutamine was assayed revealing that this portion does not play any role in the intrinsic transport function of the human SLC38A9. Different features for glutamine and arginine transport were revealed: human SLC38A9 is competent for glutamine efflux, while that of arginine is negligible. In line with these results, imposed ∆pH stimulated glutamine, not arginine transport. Arginine plays, on the contrary, a modulatory function and is able to stimulate glutamine efflux. Interestingly, reciprocal inhibition experiments also supported by bioinformatics, suggested that glutamine and arginine may bind to different sites in the human SLC38A9 transporter.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Proteoliposome reconstitution of hSLC38A9 WT and mutants.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0005273619301567-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1863, Issue 9〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 3 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochemical and Biophysical Research Communications, Volume 516, Issue 4〈/p〉 〈p〉Author(s): Shuangdong Chen, Yixiao Gu, Qinxue Dai, Yanshu He, Junlu Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Sirtuin1 (SIRT1), which is regulated by microRNA-34a (miR-34a), can modulate pathophysiology processes, including nonalcoholic fatty liver disease and intestinal ischemia/reperfusion injury. We previously reported that SIRT1, an NAD〈sup〉+〈/sup〉-dependent deacetylase, plays a vital role in the development of neuropathic pain. However, the role of miR-34a/SIRT1 in complete Freund's adjuvant (CFA)-induced inflammatory pain remains unclear. In the present study, we examined miR-34a and SIRT1 in CFA mice. MiR-34a levels increased, while SIRT1 decreased in the spinal cord. Inhibiting miR-34a by intrathecal injection of miR-34a antagomir attenuated CFA-induced pain behavior. Moreover, miR-34a antagomir inhibited the CFA-induced SIRT1 decrease in the spinal cord. Furthermore, the analgesic effect of miR-34a antagomir was abrogated by the SIRT1 inhibitor EX-527. Our data provide support that the underlying mechanisms of miR-34a in promoting inflammatory pain may involve negative regulation of SIRT1.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1861, Issue 9〈/p〉 〈p〉Author(s): Oumaima Et-Thakafy, Fanny Guyomarc'h, Christelle Lopez〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The biological membrane surrounding milk fat globules (MFGM) exhibits lateral phase separation of lipids, interpreted as gel or liquid-ordered phase sphingomyelin-rich (milk SM) domains dispersed in a fluid continuous lipid phase. The objective of this study was to investigate whether changes in the phase state of milk SM-rich domains induced by temperature (T 〈 Tm or T 〉 Tm) or cholesterol affected the Young modulus of the lipid membrane. Supported lipid bilayers composed of MFGM polar lipids, milk SM or milk SM/cholesterol (50:50 mol) were investigated at 20 °C and 50 °C using atomic force microscopy (AFM) and force spectroscopy. At 20 °C, gel-phase SM-rich domains and the surrounding fluid phase of the MFGM polar lipids exhibited Young modulus values of 10–20 MPa and 4–6 MPa, respectively. Upon heating at 50 °C, the milk SM-rich domains in MFGM bilayers as well as pure milk SM bilayers melted, leading to the formation of a homogeneous membrane with similar Young modulus values to that of a fluid phase (0–5 MPa). Upon addition of cholesterol to the milk SM to reach 50:50 mol%, membranes in the liquid-ordered phase exhibited Young modulus values of a few MPa, at either 20 or 50 °C. This indicated that the presence of cholesterol fluidized milk SM membranes and that the Young modulus was weakly affected by the temperature. These results open perspectives for the development of milk polar lipid based vesicles with modulated mechanical properties.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0005273619301555-ga1.jpg" width="317" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 16 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Tetrahedron, Volume 75, Issue 33〈/p〉 〈p〉Author(s): Mathilde Pantin, Florent Bodinier, Jordan Saillour, Yassine M. Youssouf, Fabien Boeda, Morwenna S.M. Pearson-Long, Philippe Bertus〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A convenient access to 2-hydroxycyclopentenones was designed from acylcyanohydrins, by using titanacyclopropane complexes as nucleophilic partners and an intramolecular aldol condensation in basic conditions. The development of a one-pot procedure allows a step- and atom-economic process, and the use of Grignard reagents other than ethylmagnesium bromide provided valuable 3,4-disubstituted 2-hydroxycyclopentenones. The utility of the hydroxy group was illustrated by further functionalization of the α-position using palladium-mediated cross-coupling reactions.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0040402019307525-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Advances in Water Resources, Volume 131〈/p〉 〈p〉Author(s): Shaokun He, Shenglian Guo, Kebing Chen, Lele Deng, Zhen Liao, Feng Xiong, Jiabo Yin〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The optimal impoundment operation of cascade reservoirs can dramatically improve the utilization of water resources. However, their complex non-convexity and computational costs pose challenges to optimal hydroelectricity output and limit further development of joint operation within larger-scale cascade reservoirs. In recent decades, parallel dynamic programming (PDP) has emerged as a means of alleviating the ‘curse of dimensionality’ in the mid-long term reservoir operation with more involved computing processors. But it still can't effectively solve the daily impoundment operation of more than three reservoirs. Here, we propose a novel method called importance sampling-PDP (IS-PDP) algorithm in which the merits of PDP are integrated with importance sampling and successive approximation strategy. Importance sampling is first used to construct the state vectors of each period by introducing ‘Manhattan distance’ in the discrete state space. Then the PDP recursive equation is used to find an improved solution during the iteration. The IS-PDP method is tested to optimize hydropower output for the joint operation of an 11-reservoir system located in the upper Yangtze River basin of China after establishing impoundment operation by advancing impoundment timings and rising water levels. We find that our methodology could effectively deal with the ‘curse of dimensionality’ for such mega reservoir systems and make better use of water resources in comparison to the Standard Operation Policy (SOP). Given its computational efficiency and robust convergence, the methodology is an attractive alternative for non-convex operation of large-scale cascade reservoirs.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Zhi-Hu Wang, Hong-Wei He, Guo-Sai Liu, Xu Yan, Xin Ning, Yun-Ze Long〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In conventional electrospinning (e-spinning) process, the curing mechanism can be attributed to the volatilization of solvent or the melt cooling of the jets, which were merely physical processes. To develop novel e-spinning curing mechanism, we propose a conjugate e-spinning one, in which the e-spinning precursors, solution A containing some active monomers, oxidant and solution B containing reductant, are loaded into two different syringes connected with opposite high voltage supplier, respectively. The opposite charged jets attract each other and then meet when flying from spinneret tip to collector. The redox reaction occurs when two jets meet and radicals are produced in situ which can initiate polymerization of active monomers. Then the conjugate jets solidify into fibers under reaction curing mechanism. The new method may give a new approach to produce composite functional fibers.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉Two solutions containing oxidant and reductant, respectively are electrospun into fibers via a conjugate electrospinning process under a reaction curing mechanism.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19309954-ga1.jpg" width="271" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): J.Y. Oh, Tien M. Le, A.T. Pham, D.H. Tran, D.S. Yang, B. Kang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, we investigated a correlation between superconductivity and interlayer coupling of two different alkaline (Na and K)-substituted Bi〈sub〉1·6〈/sub〉Pb〈sub〉0·4〈/sub〉Sr〈sub〉2〈/sub〉Ca〈sub〉2〈/sub〉Cu〈sub〉3〈/sub〉O〈sub〉10+δ〈/sub〉 (BSCCO) polycrystalline samples. The excess conductivity analysis by the Aslamazov-Larkin (AL) and Lawrence-Doniach (LD) theories showed that Na substitution at the Ca site induced a gradual broadening of 3D fluctuation region with increasing interlayer coupling strength, which explains a systematic increase of 〈em〉T〈/em〉〈sub〉〈em〉c〈/em〉〈/sub〉 and a decrease of normal state resistivity. On the other hand, exactly the opposite results were observed in the K-substituted samples in place of Sr. Extended x-ray absorption fine structure (EXAFS) studies revealed that substitution of Na and K generated completely different effects on the local structure around Cu atoms. It is noticeable that the Cu–O bond distance was found to decrease monotonically with the varying amounts of Na, which indicates that the CuO〈sub〉2〈/sub〉 layer is stabilized. On the while, the opposite was observed to occur with the varying amounts of K. Unlike the Cu–Ca bond which was the least affected by the substitution, the Cu–Sr bond distance increased drastically with K substitution. All these findings indicate that Na substitution at the Ca site enhances superconductivity with no loss of interlayer interaction, while K substitution at the Sr site weakens superconductivity due to the diminished interlayer interaction.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Moara M. Castro, Shima Sabbaghianrad, Pedro Henrique R. Pereira, Eric M. Mazzer, Augusta Isaac, Terence G. Langdon, Roberto B. Figueiredo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A magnesium/aluminium composite was produced by room temperature consolidation through high-pressure torsion (HPT) processing. Half-discs of the pure metals were placed side-by-side and subjected to different numbers of turns. The initially reduced interface between the phases gradually increased with increasing rotation. The composite displayed a significant ductility even after 10 turns. The distribution of hardness in the HPT-processed discs was bi-modal in the early stages of processing. As the number of turns increased and the thickness of the phases decreased there was a noticeable increase in hardness. The hardness values of the composite further increased after thermal treatment due to the formation of intermetallics within the interface between the magnesium and aluminium-rich phases.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Lipeng Xu, Fei Zhou, Jizhou Kong, Haobin Zhou, Qian Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The effects of testing temperature on the electrochemical properties of Li(Ni〈sub〉0.6〈/sub〉Mn〈sub〉0.2〈/sub〉Co〈sub〉0.2〈/sub〉)O〈sub〉2〈/sub〉 are investigated in detail. When the testing temperature is 40 °C, the Li(Ni〈sub〉0.6〈/sub〉Mn〈sub〉0.2〈/sub〉Co〈sub〉0.2〈/sub〉)O〈sub〉2〈/sub〉 cathode material possesses the highest initial discharge capacity of 162.4 mAh·g〈sup〉−1〈/sup〉 at 0.5C rate, but their cycling stability decreases markedly. When the test temperature rises up to 60 °C, the side reaction between electrolyte and cathode material becomes serious, and the Li(Ni〈sub〉0.6〈/sub〉Mn〈sub〉0.2〈/sub〉Co〈sub〉0.2〈/sub〉)O〈sub〉2〈/sub〉 cannot work. When the testing temperature decreases, the electrochemical impedances like R〈sub〉ct〈/sub〉 values increase, and then the discharge capacity at 0 °C, −10 °C and −20 °C is only 80%, 53% and 23% of that at 25 °C. Based on the electrochemical impedance spectra at different temperatures, four kinds of equivalent circuit models are classified. The cycle and rate performance of Li(Ni〈sub〉0.6〈/sub〉Mn〈sub〉0.2〈/sub〉Co〈sub〉0.2〈/sub〉)O〈sub〉2〈/sub〉 cathode material could be improved obviously through Ti〈sub〉3〈/sub〉C〈sub〉2〈/sub〉(OH)〈sub〉2〈/sub〉 modification in an extreme environment, and especially in sub-zero environment.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Kenji Yoshii, Naoshi Ikeda〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Dielectric and magnetocaloric measurements are carried out for the chromite TmCrO〈sub〉3〈/sub〉. This oxide was reported to be multiferroic below the Néel temperature (〈em〉T〈/em〉〈sub〉N〈/sub〉) of ∼125 K, likely due to a structural transformation. The dielectric response shows large dielectric constants below 300 K. However, from the analyses of loss tangent, AC conductivity and dielectric modulus, this behavior is rooted in hopping of charge carriers rather than electric dipoles, as proposed for some other chromites. No dielectric anomaly is found at 〈em〉T〈/em〉〈sub〉N〈/sub〉. The magnetocaloric effect shows that the magnetic transitions at 〈em〉T〈/em〉〈sub〉N〈/sub〉 as well as the spin reorientation temperature are of a second order. This result strongly suggests the absence of magnetostructural transition at 〈em〉T〈/em〉〈sub〉N〈/sub〉 in accord with no observation of ferroelectric transition at this temperature.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Rattiya Hongtong, Panya Thanwisai, Rattakarn Yensano, Jeffrey Nash, Sutham Srilomsak, Nonglak Meethong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Core-shell olivine-type electrospun and doped LiFePO〈sub〉4〈/sub〉/FeS/C composite fibers were synthesized via a single-step process employing an electrospinning method using LiOH·H〈sub〉2〈/sub〉O, metal sul phates, H〈sub〉3〈/sub〉PO〈sub〉4〈/sub〉, citric acid, and polyvinylpyrrolidone (PVP) as the starting materials. Electron microscopy studies showed that the mean diameter of the core-shell composite fibers was about 280 ± 20 nm with a LiFePO〈sub〉4〈/sub〉 phase forming a core with a diameter of about 100 ± 20 nm and a carbon shell with a thickness of 80 ± 20 nm. An FeS phase was formed by a direct reduction of iron (II) sulfate (FeSO〈sub〉4〈/sub〉) that was evenly distributed within the core region of the composite fibers and further improved the electronic conductivity of the fibers. Na〈sup〉1+〈/sup〉, Mg〈sup〉2+〈/sup〉, and Al〈sup〉3+〈/sup〉 doping ions affected fiber morphology and electrochemical performance. All composite fibers showed excellent electrochemical performance. However, Al〈sup〉3+〈/sup〉 ions improved the electrochemical performance of the composite fibers to a significantly greater degree than Na〈sup〉1+〈/sup〉 and Mg〈sup〉2+〈/sup〉 doping ions, increasing the electronic and ionic conductivities of the material while maintaining their core-shell composite fiber characteristics.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Electrospun LiFePO〈sub〉4〈/sub〉/FeS/C and 5% doped 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"〉〈mrow〉〈mi〉L〈/mi〉〈mi〉i〈/mi〉〈mi〉F〈/mi〉〈msubsup〉〈mrow〉〈mi〉e〈/mi〉〈/mrow〉〈mrow〉〈mn〉1〈/mn〉〈mo linebreak="badbreak"〉−〈/mo〉〈mrow〉〈mo stretchy="false"〉(〈/mo〉〈mi〉n〈/mi〉〈mi〉x〈/mi〉〈mo linebreak="badbreak"〉/〈/mo〉〈mn〉2〈/mn〉〈mo stretchy="false"〉)〈/mo〉〈/mrow〉〈/mrow〉〈mrow〉〈mn〉2〈/mn〉〈mo linebreak="badbreak"〉+〈/mo〉〈/mrow〉〈/msubsup〉〈msubsup〉〈mrow〉〈mi〉M〈/mi〉〈/mrow〉〈mrow〉〈mi〉x〈/mi〉〈/mrow〉〈mrow〉〈mi〉n〈/mi〉〈mo linebreak="badbreak"〉+〈/mo〉〈/mrow〉〈/msubsup〉〈mi〉P〈/mi〉〈msub〉〈mrow〉〈mi〉O〈/mi〉〈/mrow〉〈mrow〉〈mn〉4〈/mn〉〈/mrow〉〈/msub〉〈/mrow〉〈/math〉/FeS/C (M = Na〈sup〉1+〈/sup〉, Mg〈sup〉2+〈/sup〉, Al〈sup〉3+〈/sup〉) composites with a unique core-shell structure were synthesized via a simple single-step process to improved electrochemical properties for high performance and low cost Li-ion batteries.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838819324946-fx1.jpg" width="287" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): L.V.B. Diop, O. Isnard〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The effects of Fe substitution on the structural and magnetic properties of the HoCo〈sub〉12-〈em〉x〈/em〉〈/sub〉Fe〈sub〉〈em〉x〈/em〉〈/sub〉B〈sub〉6〈/sub〉 (0 ≤ 〈em〉x〈/em〉 ≤ 2) series of intermetallic compounds have been studied. All of the compounds form in the rhombohedral SrNi〈sub〉12〈/sub〉B〈sub〉6〈/sub〉-type structure, the lattice constants increasing linearly with 〈em〉x〈/em〉. These compounds are ferrimagnets with a small transition metal magnetic moment and exhibit a spin reorientation transition. The Curie temperature decreases from 147 K for 〈em〉x〈/em〉 = 0–105 K for 〈em〉x〈/em〉 = 2. The Fe for Co substitution leads also to a progressive decrease of the spontaneous magnetization. The spin reorientation transition temperature is significantly reduced upon Fe for Co substitution whereas the compensation temperature is much less sensitive to the Fe composition.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 224〈/p〉 〈p〉Author(s): Hayam M. Lotfy, Sarah S. Saleh, Christine M. El-Maraghy〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉An analytical investigation was carried out to study the treatment and amplification of the spectral signals produced by critical concentrations with high accuracy and precision using two advanced approaches. The factorized-spectrum approach was applied through two novel methods which were: absorptivity centering technique via both: factorized zero order absorption spectrum (ACT-FSD〈sup〉0〈/sup〉〈sub〉∆A〈/sub〉) and factorized ratio spectrum (ACT-FSR〈sub〉∆P〈/sub〉). The proposed methods were found to be linear in the ranges of (15–100 μg/mL) and (3–40 μg/mL) for ASP and MTO, respectively. Those methods were compared to the methods following the geometrical standard addition approach: ratio H-point standard addition method (RHPSAM) and geometrical induced amplitude modulation (GIAM). The approaches were applied for the determination of the minor component metoclopramide in its mixture with the major component aspirin in the challengeable ratio of (1,90) respectively in a white multicomponent system. The results obtained from the proposed approaches were statistically compared with each other. The methods were validated according to ICH guidelines where the results were found to be within the acceptable limits. The methods were found to be accurate and reliable for the determination of metoclopramide critical concentration besides aspirin concentration. The results of single factor ANOVA analysis indicated that there is no significant difference among the developed methods. These methods provided simple resolution of this binary combination from synthetic mixtures and pharmaceutical preparation and can be conveniently adopted for routine quality control analysis.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S1386142519307292-ga1.jpg" width="325" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Maxim S. Likhanov, Vladislav O. Zhupanov, Valeriy Yu Verchenko, Andrei A. Gippius, Sergei V. Zhurenko, Alexey V. Tkachev, Dina I. Fazlizhanova, David Berthebaud, Andrei V. Shevelkov〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We present a new Fe〈sub〉1–〈em〉x〈/em〉〈/sub〉Re〈sub〉〈em〉x〈/em〉〈/sub〉Ga〈sub〉3〈/sub〉 solid solution, in which a 5〈em〉d〈/em〉-metal––rhenium––partially substitutes for iron to the limiting composition of 〈em〉x〈/em〉 = 0.10. The crystal structure refined for the composition Fe〈sub〉0.91〈/sub〉Re〈sub〉0.09〈/sub〉Ga〈sub〉3〈/sub〉 shows the expected increase in the unit cell parameters compared to the parent FeGa〈sub〉3〈/sub〉 compound, however the M–M (M = Fe, Re) distance decreases within the M–M dumbbell, indicating an increased M–M bonding density. Therein, investigation of the local structure by means of 〈sup〉69,71〈/sup〉Ga NQR spectroscopy revealed the formation of homonuclear Fe–Fe and Re–Re dumbbells. Transport and thermoelectric properties have been investigated for the Re-substituted FeGa〈sub〉3〈/sub〉. Electrical transport measurements showed preservation of the nonmetallic conductivity of Fe〈sub〉1–〈em〉x〈/em〉〈/sub〉Re〈sub〉〈em〉x〈/em〉〈/sub〉Ga〈sub〉3〈/sub〉 despite the decrease of the valence electron concentration from 17 to 16.9 electrons per formula. At low temperatures, Fe〈sub〉1–〈em〉x〈/em〉〈/sub〉Re〈sub〉〈em〉x〈/em〉〈/sub〉Ga〈sub〉3〈/sub〉 is a 〈em〉p〈/em〉-type semiconductor with the band gap of 0.4 eV, but with increasing temperature the sign of the dominant charge carriers changes. Owing to the alloying effect, Fe〈sub〉1–〈em〉x〈/em〉〈/sub〉Re〈sub〉〈em〉x〈/em〉〈/sub〉Ga〈sub〉3〈/sub〉 displays 1.5 times lower thermal conductivity than FeGa〈sub〉3〈/sub〉, which increases at high temperatures because of the growing contribution of the electronic term.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838819325198-fx1.jpg" width="454" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Biomass and Bioenergy, Volume 127〈/p〉 〈p〉Author(s): Shuping Zhang, Shuguang Zhu, Houlei Zhang, Xinzhi Liu, Huiyan Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Effect of combined pretreatment on the mechanism of pyrolysis behavior and pyrolysis products (bio-oil, non-condensable gas and char) of rice husk was investigated using thermogravimetric analyzer (TGA) and laboratory-scale fixed-bed reactor. A coupling method combining iso-conversional method and model-fitting method was used to obtain the pyrolysis kinetic parameter. Pyrolysis kinetics results indicated that activation energy (〈em〉E〈/em〉) gradually increased with the increase of conversion rate (〈em〉α〈/em〉), which was due to the differences in thermal stability of biomass components. Acid washing pretreatment slightly increased the average activation energy (〈em〉E〈/em〉〈sub〉a〈/sub〉), and then subsequent torrefaction process further increased it. The entire pyrolysis reaction process of all the rice husk samples can be described by the reaction-order model. In addition, a laboratory-scale fixed-bed reactor was used to investigate the yields and detailed characteristics of pyrolysis products. The results suggested that phenols and sugars contents in bio-oil increased, while that of small-molecule components with high thermal instability decreased, which was favor for the storage and subsequent utilization of bio-oil. Rice husk char obtained from pyrolysis also has the potential for preparation of silica products. We concluded that combined pretreatment of washing and torrefaction significantly improved the thermochemical utilization potential of rice husk for fuels and chemicals by pyrolysis.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0961953419302429-fx1.jpg" width="307" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Jiashu Zhang, Weiyao Zhao, Zhenjie Feng, Jun-Yi Ge, Jincang Zhang, Shixun Cao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We report the crystal growth, structure analysis and magnetic phase transitions in the single crystal Sm〈sub〉0.15〈/sub〉Dy〈sub〉0.85〈/sub〉FeO〈sub〉3〈/sub〉. The high-quality of the crystal is verified by X-ray diffraction technique. Our research reveals that: 1) the iron sublattice spin reorientation (SR) transition emerges at 25 K, and ends at 10 K; 2) the rare earth antiferromagnetic (AF) order transition happens at 2.6 K; 3) there is a special wasp-waist hysteresis loop at low temperatures. Knowledge of such phase transitions in rare earth orthoferrite system is of potential importance for applications and theoretical studies.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Ji Soo Yu, Sung Hun Kim, Minh Tan Man, Hong Seok Lee〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We have successfully demonstrated the colloidal hot-injection process to easily obtain the Mn-doped ZnSe quantum dots (QDs) with a size of about 4–5 nm, and 〈em〉d〈/em〉-spacing is 0.31 nm, corresponding to the (1 1 1) lattice plane of ZnSe. Experimental results show that UV–vis absorption and fluorescence spectra were recorded to elucidate the role of Mn〈sup〉2+〈/sup〉 ions substituted into ZnSe, which resulted in the carrier transfer of luminescent sites by a small amount of Mn〈sup〉2+〈/sup〉 dopant. The small size of the Mn-doped ZnSe QDs offers intriguing opportunities for their application in photonic, bioimaging, and spintronics devices.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19309905-ga1.jpg" width="298" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Mohamad Fahrul Radzi Hanifah, Juhana Jaafar, M.H.D. Othman, A.F. Ismail, M.A. Rahman, Norhaniza Yusof, Farhana Aziz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nanocluster-like Pt nanoparticles/reduced graphene oxide nanocomposite catalyst (NC-PtNPs/RGO) was synthesized through a novel one-step process of chemical reduction-assisted hydrothermal reaction by using formic acid as reducing agent. The crystallinity, morphology and composition of the NC-PtNPs/RGO catalysts were extensively characterized. The as-prepared NC-PtNPs/RGO catalysts exhibited higher electro-catalytic activity towards methanol oxidation than carbon black (CB)/PtNPs catalyst and could be ascribed to the high dispersion of NC-Pt NPs with large electrochemical surface area, release more exposure of active sites by NC-PtNPs structure and synergy effect of RGO.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Zhenhua Wang, Yi Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Σ3 boundaries improve the intergranular corrosion resistance of high nitrogen austenitic stainless steels. However, the regeneration of these boundaries is, unfortunately, accompanied by significant grain coarsening. 18Mn18Cr0.5N and 18Mn18Cr0.6N steels were thermo-mechanically processed and the corresponding microstructures were evaluated. Formation mechanisms were proposed for Σ1 boundaries in different R-Σ3-Σ1-type junctions. These boundaries formed during grain growth accompanying Σ3 formation and reaction. After 30% cold tension and cyclic heating between 500 °C and 1100 °C, numerous Σ1 boundaries were formed and disrupted the high angle grain boundary network efficiently. Moreover, a small grain size was maintained. Σ1 boundaries have significant application potential in grain boundary engineering.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Rui Wang, Dongdong Gu, Lixia Xi, Kaijie Lin, Meng Guo, Hongmei Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Selective laser melting (SLM), as a rapidly developed layer-by-layer 3D printing technology, has been demonstrated that it can be used for additive manufacturing of multi-materials. In this work, TiB〈sub〉2〈/sub〉/Ti6Al4V multi-materials were manufactured by SLM. The results showed that interfacial microstructures consisting of un-melted TiB〈sub〉2〈/sub〉 powders, columnar TiB crystals, and acicular TiB crystals were formed in the molten pool. Meanwhile, a variation nanohardness was developed with chemical compositions at the interfacial regions, owing to an in-situ reaction of Ti and TiB〈sub〉2〈/sub〉. The first-principle calculations were used to reveal the axial growth of TiB crystals as well as the different hardness of this system.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19310006-ga1.jpg" width="346" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Siyao Xie, Ruidi Li, Linjun Tang, Tiechui Yuan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The diffusion behavior of Al in FeCoCrNiMo〈sub〉x〈/sub〉 high-entropy alloys (HEAs) at temperatures ranging from 773 to 873 K with and without pulse current was studied in this paper. The diffusion coefficients 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.svg"〉〈mi〉D〈/mi〉〈/math〉 was determined based on the Fick’s law and corresponding pre-exponential factor 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.svg"〉〈msub〉〈mi〉D〈/mi〉〈mn〉0〈/mn〉〈/msub〉〈/math〉, as well as activation energy 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si4.svg"〉〈msub〉〈mi〉Q〈/mi〉〈mi〉D〈/mi〉〈/msub〉〈/math〉. It was found that the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.svg"〉〈mi〉D〈/mi〉〈/math〉 under pulse current dramatically increased about hundreds of times in contrast with that without current. In addition, the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.svg"〉〈msub〉〈mi〉D〈/mi〉〈mn〉0〈/mn〉〈/msub〉〈/math〉 and 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si4.svg"〉〈msub〉〈mi〉Q〈/mi〉〈mi〉D〈/mi〉〈/msub〉〈/math〉 were determined to reduce from 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si5.svg"〉〈mrow〉〈msubsup〉〈mrow〉〈mn〉1.369〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉0.324〈/mn〉〈/mrow〉〈mrow〉〈mo〉+〈/mo〉〈mn〉0.424〈/mn〉〈/mrow〉〈/msubsup〉〈mo〉×〈/mo〉〈msup〉〈mrow〉〈mn〉10〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉13〈/mn〉〈/mrow〉〈/msup〉〈/mrow〉〈/math〉 to 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si17.svg"〉〈mrow〉〈msubsup〉〈mrow〉〈mn〉5.016〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉1.984〈/mn〉〈/mrow〉〈mrow〉〈mo〉+〈/mo〉〈mn〉3.284〈/mn〉〈/mrow〉〈/msubsup〉〈mo〉×〈/mo〉〈msup〉〈mrow〉〈mn〉10〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉15〈/mn〉〈/mrow〉〈/msup〉〈/mrow〉〈/math〉 m〈sup〉2〈/sup〉/s, and from 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si6.svg"〉〈mrow〉〈mn〉39.7〈/mn〉〈mo〉±〈/mo〉〈mn〉1.8〈/mn〉〈/mrow〉〈/math〉 to 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si18.svg"〉〈mrow〉〈mn〉21.6〈/mn〉〈mo〉±〈/mo〉〈mn〉3.4〈/mn〉〈/mrow〉〈/math〉 kJ/mol respectively with the Mo contents increasing from Mo〈sub〉0〈/sub〉 to Mo〈sub〉0.2〈/sub〉 without pulse current. The introduction of pulse current into the diffusion couples dramatically promoted the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.svg"〉〈msub〉〈mi〉D〈/mi〉〈mn〉0〈/mn〉〈/msub〉〈/math〉 at all the diffusion couples. However, the pulse current was ascertained to obviously increase the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si4.svg"〉〈msub〉〈mi〉Q〈/mi〉〈mi〉D〈/mi〉〈/msub〉〈/math〉 in contrast to that of diffusion couples without pulse current.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19309899-ga1.jpg" width="271" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Yuliang Jiang, Xueyan Fu, Zidong Zhang, Wei Du, Peitao Xie, Chuanbing Cheng, Runhua Fan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Carbon nanofibers embedded with magnetic Fe〈sub〉3〈/sub〉C nanoparticles have been synthesized using electrospinning technique, followed by one-step carbonization. By using Fe〈sub〉3〈/sub〉C/C nanofibers as filler with 10% content, the sample can achieve a minimum reflection loss (RL) of −54.94 dB with a thickness of 1.36 mm, as well as the broad effective absorption bandwidth (EAB) can reach to 4.5 GHz (13.3–17.8 GHz) at the thickness of 1.55 mm. The superior properties might be due to the synergistic effects of dielectric loss, magnetic loss, multiple scattering and reflection. This work presents a facile and promising method to produce high performance microwave absorption materials with thin thickness, light weight and strong absorption.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): E.J. Pickering, K.A. Christofidou, H.J. Stone, N.G. Jones〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In order to reduce the environmental impact of air travel, it is desirable that the efficiencies of gas turbine engines are increased. One way to achieve this goal is to increase the operating temperatures of the engine cores. Unfortunately for aero-engine manufacturers, the temperature capability limits of the Ni-base superalloys used currently have been reached. Hence, new alloys need to be developed that are capable of operating at significantly higher temperatures. In this article, the potential of tantalum-base superalloys is discussed and explored. A suite of alloys based on the Ta-Al-Co system was investigated. It was found that an array of fine carbide precipitates was formed in the Ta-rich matrix in a subset of the alloys, which is promising in terms of developing a strong and damage-tolerant microstructure, but that the elemental partitioning of Al out of the matrix accompanying precipitation is likely to degrade environmental resistance. Nevertheless, it is believed that the design principles described have the potential to facilitate the development of the next generation of high-temperature alloys based on systems of this type.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): C.Q. Zhou, Q.A. Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In order to understand the effect of Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 nanoparticles on crystallite growth kinetics of nanocrystalline Mg, the crystallite growth characteristics in a Mg−Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 composite and a pure Mg sample were comparatively investigated in this work. The crystallite growth exponents of nanocrystalline Mg in the Mg−Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 composite and pure Mg were determined as 〈em〉n〈/em〉 = 5 and 〈em〉n〈/em〉 = 4, respectively. Meanwhile, the activation energy for crystallite growth in Mg−Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 composite was calculated to be 118.8 kJ/mol, which is higher than 97.1 kJ/mol in pure nanocrystalline Mg. Further studies reveal that the rise of crystallite growth exponent and increase of activation energy in the Mg−Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 composite are primarily attributed to the pinning effect of Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 nanoparticles at crystallite boundaries of Mg.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 804〈/p〉 〈p〉Author(s): Liming Tan, Yunping Li, Wenkai Deng, Yong Liu, Feng Liu, Yan Nie, Liang Jiang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Three Ni-base powder metallurgy superalloys have been developed recently, and tensile tests at temperatures ranging from room temperature (RT) to 815 °C were conducted on them. The results conformed their excellent tensile properties, in comparison with several other existed polycrystalline superalloys. In this work, by means of microstructure characterization, thermal dynamic calculations, and theoretical modeling, different strengthening mechanisms including precipitation strengthening, grain boundary strengthening, solid solution strengthening, and Orowan strengthening, were found to contribute to the yield strength in different degrees, which would help to further enhance the tensile properties of these alloys through composition design and processing optimization thereafter.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838819324892-fx1.jpg" width="459" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 223〈/p〉 〈p〉Author(s): Rui Zhang, Yun Liu, Lin Kong, Xian-Yun Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, a two photon absorbing (TPA) material consisting silver nanoparticles and triphenylamine-thiol derivative (TBS) has been prepared through interfacial coordination effect according to soft-hard-acid-base principle. The interfacial structure and morphology of the hybrid are researched in detail. Linear and nonlinear optical properties of the hybrid are studied. Upon interfacial coordination, the hybrid shows red-shifted UV–Vis absorption, causing from enhanced electronic drawing strength due to existence of Ag atom. The results also indicate that the surface Plasmon resonance (SPR) effect of Ag nanoparticles (~6 nm) brings about enhancement in single photon fluorescence emission and two photon absorption. Compared with free TBS, Ag-TBS hybrids show higher TPA cross-section (δ), which is 8784 GM for TBS and up to 103876 GM for Ag-TBS hybrid, showing ~12 fold increase. Due to excellent TPA property, the hybrids have good application in the field of optical power limiting and its limiting threshold is 0.49 J/cm〈sup〉−2〈/sup〉. This type of interfacial coordination induced hybrid provides a promising strategy to regulate linear optical properties and optimize nonlinear performance.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉A thiol-Ag nanohybrid has been prepared through interfacial coordination effect and self-assembly process to optimize the TPA performance.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S1386142519307280-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): C.Q. Zhang, W. Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The Al〈sub〉3〈/sub〉Ti intermetallic compound (IMC) layer growth kinetics at Al-Ti interface was investigated. Surprisingly an abnormal effect of temperature was observed with a thicker IMC layer formed at lower annealing temperature due to the much faster Al〈sub〉3〈/sub〉Ti grain coarsening at a higher temperature, the IMC layer growth at 630 °C became slower than that at 600 °C after a certain annealing time. The quantitative influence of grain size on effective diffusion coefficient was analysed. Calculations showed that the lattice diffusion makes little contribution to the effective diffusion coefficient. Grain boundary diffusion, therefore, dominates for all the annealing conditions studied.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Marine Geology, Volume 416〈/p〉 〈p〉Author(s): Pedro Terrinha, Henrique Duarte, Pedro Brito, João Noiva, Carlos Ribeiro, Rachid Omira, Maria Ana Baptista, Miguel Miranda, Vitor Magalhães, Cristina Roque, Tagusdelta cruise team〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The stratigraphy of the Tagus river ebb-tidal delta off Lisbon (Portugal) is investigated using high resolution multichannel seismic reflection profiles with the purpose of searching for sedimentary or erosive features associated with landslides. The Tagus delta is sub-divided in two prograding seismic units of 17 ky to 13 ky and 13 ky to Present based on the calibration of seismic lines using gravity and box-cores in the Tagus pro-delta. We report the existence of a buried landslide with 11 km of length, 3.5 km of width and a maximum thickness of 20 m that accounted for the collapse of half of the upper unit of the Tagus river delta front in Holocene times. The non-collapsed half of the delta front contains extensive shallow gas of still unknown origin and nature. An estimated age of ~8 ky BP for the Tagus delta landslide is proposed based on stratigraphic correlation. The trigger mechanisms of the newly identified Tagus landslide are discussed as well as of the several landslides also found in the lower delta unit. These findings present a first step towards a future assessment of the susceptibility of the nearby coastal areas and the off-shore infrastructures to hazards related to such large collapses.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Atmospheric Environment, Volume 214〈/p〉 〈p〉Author(s): Daniela Polag, Frank Keppler〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Methane (CH〈sub〉4〈/sub〉) is a potent greenhouse gas released to the atmosphere by various natural and anthropogenic sources. Numerous studies have been conducted to quantify the major and minor CH〈sub〉4〈/sub〉 sources on spatial and temporal time scales. A minor source of the atmospheric global CH〈sub〉4〈/sub〉 budget is the direct release of CH〈sub〉4〈/sub〉 from the living human body. Based on available data from recent publications, for the first time, CH〈sub〉4〈/sub〉 emissions from human breath and flatus are estimated on a global scale taking into account dominant factors influencing emission, such as age, ethnicity, and gender. Human CH〈sub〉4〈/sub〉 emissions are compared between preindustrial times (1750), present age (2017) and future prediction (2100) using demographic data based on World Population Prospects 2017 of the United Nations (UN 2017). In preindustrial times the global CH〈sub〉4〈/sub〉 release by humans is estimated at 34 ± 28 Gg and then substantially increase by a factor of ten reaching 344 ± 255 Gg by 2017. Emissions are estimated to further increase by almost fourfold to a value of 1221 ± 672 Gg by 2100, even though the rise in population is predicted to only increase by 50%. This nonlinear relationship is related to the predicted change in population structure affecting the number of CH〈sub〉4〈/sub〉 producers. In contrast, for the year 2100 the simplified non-weighted estimation which merely considers the expected increase in population would only account for 612 ± 169 Gg. The discrepancy between the simplified non-weighted and weighted estimations of human CH〈sub〉4〈/sub〉 emissions emphasises the importance of factor-based calculations in order to compile more accurate data.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Palaeogeography, Palaeoclimatology, Palaeoecology〈/p〉 〈p〉Author(s): William J. Freimuth, David J. Varricchio〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We describe the diversity and abundance of insect (specifically hymenopterans and coleopterans) pupation structures in the Upper Cretaceous (Campanian) Two Medicine Formation at the Egg Mountain locality, western Montana, U.S.A., an important dinosaur nesting site. The study interval comprises a massive calcareous siltstone and indurated silty limestone horizons interpreted as the product of cumulative paleosols. A 7 m by 11 m area was quarried with a jackhammer at intervals of 12.5 cm thickness for a 1.5 m thick stratigraphic section. The ichnoassemblage comprises four morphotypes (small, medium, large, and wide) assigned to 〈em〉Fictovichnus sciuttoi〈/em〉, of which three represent wasp (hymenopteran) cocoons while the fourth (wide) type potentially was produced by a coleopteran. Medium and small 〈em〉F. sciuttoi〈/em〉 are dominant while large and wide 〈em〉Fictovichnus〈/em〉 are less common and absent in some sample intervals. Other probable insect traces include partial perforations in cocoons (〈em〉Tombownichnus〈/em〉), isolated burrows, and an enigmatic hemispherical trace. Material is representative of a depauperate 〈em〉Celliforma〈/em〉 ichnofacies. Pervasive cocoons and other traces throughout the sequence suggest persistent soil conditions suitable for insect nesting and pupation, and suggest an absence of sediment pulses of sufficient thickness to prohibit thorough colonization. Peaks in pupation chamber abundance may reflect episodes of reduced sedimentation rates otherwise unseen in the absence of primary bedding structures. Well-drained and friable soil conditions favorable for insect nesting also may help explain the abundance of dinosaur nests and other vertebrate nesting events in associated strata as well as the presence of small terrestrial forms.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Geodynamics, Volume 129〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 1 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Tetrahedron Letters, Volume 60, Issue 31〈/p〉 〈p〉Author(s): Tao-Shan Jiang, Yuhui Zhou, Long Dai, Xiaojun Liu, Xiuli Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A metal-free 〈em〉p〈/em〉-toluenesulfonic acid (TsOH·H〈sub〉2〈/sub〉O) mediated synthesis of 3-ketoquinolines from anilines, enaminones and DMSO has been developed. In this transformation, DMSO was activated by TsOH·H〈sub〉2〈/sub〉O and provided the one-carbon unit of the 3-ketoquinolines. A plausible mechanism involving an electrophilic sulfenium ion intermediate was proposed.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0040403919306562-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉