ALBERT

Description: 〈p〉Publication date: 1 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Energy, Volumes 233–234〈/p〉 〈p〉Author(s): Rong Gu, Jing Ding, Yarong Wang, Qinquan Yuan, Weilong Wang, Jianfeng Lu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Steam methane reforming is suitable for thermochemical energy storage because of its large reaction enthalpy and high hydrogen content in reaction products. In this paper, heat transfer and storage performance of steam methane reforming in a tubular reactor heated by focused solar simulator is experimental demonstrated and numerically analyzed. According to experimental results, methane conversion remarkably decreases with inlet flow rate rising, while thermochemical energy storage efficiency first increases for more reactants and then decreases with methane conversion dropping. As incident energy flux rises, methane conversion increases with bed temperature rising, and the thermochemical energy storage efficiency reaches its maximum of 11.3% with central heat flux of 285.6 kW/m〈sup〉2〈/sup〉. Three-dimensional transport and volumetric reaction model with concentrated energy flux boundary condition is established and validated, and local and integral energy transport and storage performance are further analyzed. Along flow direction, the maximum reaction rate appears before the focal point with maximum energy flux. The tendencies of methane conversion and thermochemical energy storage efficiency are very similar under different inlet conditions, and higher inlet temperature and appropriate steam to methane ratio benefit thermochemical energy storage. The structures of catalyst bed and reactor are critical important for thermochemical energy storage process. As bed length increases, the methane conversion and thermochemical energy storage efficiency first increase with the increase of positive reaction and then decrease with the increase of reverse reaction, and the optimal length is a little larger than focal spot diameter. When bed porosity is increased, the methane conversion and thermochemical energy storage efficiency first increases with the flow resistance decreasing and then decreases with catalyst amount decreasing, and optimal porosity is 0.45. Heat loss in heating side of bed region play major role in heat storage, and the thermochemical energy storage efficiency can be improved to 34.8% by using insulation and coating.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Marine Policy, Volume 99〈/p〉 〈p〉Author(s): Bong-Tae Kim, Christopher L. Brown, Do-Hoon Kim〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We assess the vulnerability to climate change of Korean aquaculture based on predicted changes in seawater temperature and salinity in adjacent sea areas of the Korean Peninsula according to representative concentration pathways (RCP) scenarios. Unlike previous studies that have been conducted mostly on a national scale, we classify 14 farming species in major production regions of the Republic of Korea, and assess their vulnerability for each region, using the indicator-based method and the Intergovernmental Panel on Climate Change's definition of vulnerability in order to overcome limitations in developing specific adaptation strategies within a country. First, for each exposure, sensitivity, and adaptive capacity, specific and proper indicators are selected. Subsequently, these indicators are estimated and weighted to analyze vulnerability to climate change. The results show that the absolute level of vulnerability is high in a long-term period of RCP8.5 in which exposure becomes severe, whereas the relative vulnerability is similar among farming species and regions. Specifically, vulnerability is at the highest level in seaweed, such as laver and sea mustard, while fish, shrimp, and abalone are relatively less vulnerable to climate change.〈/p〉〈/div〉

Description: 〈p〉Publication date: 13 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Cell, Volume 175, Issue 7〈/p〉 〈p〉Author(s): Zheng Shi, Zachary T. Graber, Tobias Baumgart, Howard A. Stone, Adam E. Cohen〈/p〉 〈h5〉Summary〈/h5〉 〈div〉〈p〉The fluid-mosaic model posits a liquid-like plasma membrane, which can flow in response to tension gradients. It is widely assumed that membrane flow transmits local changes in membrane tension across the cell in milliseconds, mediating long-range signaling. Here, we show that propagation of membrane tension occurs quickly in cell-attached blebs but is largely suppressed in intact cells. The failure of tension to propagate in cells is explained by a fluid dynamical model that incorporates the flow resistance from cytoskeleton-bound transmembrane proteins. Perturbations to tension propagate diffusively, with a diffusion coefficient 〈em〉D〈/em〉〈sub〉σ〈/sub〉 ∼0.024 μm〈sup〉2〈/sup〉/s in HeLa cells. In primary endothelial cells, local increases in membrane tension lead only to local activation of mechanosensitive ion channels and to local vesicle fusion. Thus, membrane tension is not a mediator of long-range intracellular signaling, but local variations in tension mediate distinct processes in sub-cellular domains.〈/p〉〈/div〉 〈h5〉Graphical Abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0092867418313059-fx1.jpg" width="375" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Energy Strategy Reviews, Volume 22〈/p〉 〈p〉Author(s): Mohammed Kharbach, Tarik Chfadi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉This paper investigates the impact of oil prices on a single public utility's electricity production by using a cointegration approach. We estimate the elasticity of the electricity produced, by different fuel sources (coal, oil, and water) in the Moroccan power system, to oil prices.〈/p〉 〈p〉We find that, in the long run, the elasticities of the electricity produced by coal and oil to oil prices are similar. On the contrary, significant differences exist in the short-term elasticity of the electricity produced by coal and oil to oil prices. We also find that hydropower could substitute the electricity produced by coal in the short run but not in the long run.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Energy Strategy Reviews, Volume 22〈/p〉 〈p〉Author(s): Mehmet Melikoglu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Coal is the primary energy source for electricity generation around the globe and it is projected that this dominance will continue for at least a few more decades. However, coal combustion for power generation generates significant greenhouse gas emissions as well as NO〈sub〉x〈/sub〉/SO〈sub〉x〈/sub〉 and particulates emissions. Therefore, future consumption of coal for electricity generation must be cleaner and efficient. This can be achieved by utilizing different processes and technologies also known as clean coal technologies. In this study, global development in clean coal technologies is scrutinized and an up to date review about the subject is prepared. In addition, potential utilization of clean coal technologies in Turkey is assessed based on the government's recent energy policy decision of increasing lignite based installed capacity from nearly 10,000 MW to 30,000 MW. As a result, an up to date review about the past, present and future of clean coal technologies in Turkey is prepared. Detailed analysis showed that research & development studies on clean coal technologies are at early stages in Turkey. This means that there won't be enough time to locally develop clean coal technologies while fulfilling the Vision 2023 lignite based installed capacity target in the next 5–6 years. As a result, it is suggested that Turkey should first purchase clean coal technologies from developed countries with know-how and technology transfer clauses in order to increase lignite-fired coal power plant capacity without skyrocketing Turkey's greenhouse gas emissions. In the meantime, local research & development studies must be fostered in order to develop indigenous clean coal technologies. Finally, it is believed that the discussion in this study could help the researchers around the globe broaden their knowledge about clean coal technologies and help the authorities in Turkey to design the country's coal based energy future in a more sustainable manner.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Carbon, Volume 142〈/p〉 〈p〉Author(s): Baoyin Jin, Ding-Bang Xiong, Zhanqiu Tan, Genlian Fan, Qiang Guo, Yishi Su, Zhiqiang Li, Di Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Corrosion protection of metals is of great importance due to their widespread use. Graphene (Gr) has shown promising corrosion resistance as a coating for metals, however, its excellent strengthening effect that has been widely shown is suppressed in such coating applications. Here, inspired by positive anti-corrosion role of graphene coating for metal macro-foils, graphene encapsulated Cu (Cu@Gr) micro-/nano-flakes are designed and fabricated, and then used as building blocks for assembling bulk Gr/Cu composites. Thanks to its protective role and strengthening effect of uniformly dispersed graphene in Cu matrix, as compared to bare copper, corrosion rate of the as-fabricated bulk Gr/Cu composites is reduced by 50% in NaCl solution and its yield strength is increased by ∼180% (2.5 vol% Gr) simultaneously, without deterioration on electrical conductivity. The anti-corrosion mechanisms are understood by studying etching behavior of the Cu@Gr flakes in FeCl〈sub〉3〈/sub〉 solution, and surface morphology evolution in the samples subjected to salt spray corrosion, and electrochemical corrosion tests. Graphene's anti-corrosion effect is also reflected by an anisotropic corrosion behavior of the Gr/Cu composite because of a “brick-and-mortar” microstructure. The results presented here shed light on expanding metal matrix composite's applications to a wider range and more complex situation by incorporating graphene.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0008622318310078-fx1.jpg" width="239" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Transport Geography, Volume 73〈/p〉 〈p〉Author(s): Chengxi Liu, Yusak O. Susilo, Dimas B.E. Dharmowijoyo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The activity space of an individual is defined as the activity-travel environment which a traveller is using for his or her activities (Axhausen et al., 2002). It is limited by this individual's ability and resources, such as available time for travel as well as his or her anchor points. However, most existing studies have focused on single individual activity space, ignoring the fact that individuals' activities often interact with that of his or her family members'. In this paper a multivariate model is proposed where the correlation between travel time of fathers and mothers, and the correlation between the activity space and travel time are modelled explicitly. The estimated correlations from these joint distributions provide insights into both the intra-household interactions in daily travel and the intrinsic relationships of the hidden limits in the dimensions of space and time. The travel time limits are modelled using a stochastic frontier model component, which can estimate an unobserved upper or lower limit for travel time expenditure. This limit usually refers to the maximum travel time budget or minimum travel time need, which denotes the maximum or minimum amount of travel time that an individual is willing or able to allocate per day. The concept of the confidence ellipse is used as a measure of activity space constructed from the multi-day travel diary data. It is hypothesised that the unobserved travel time limits and activity space sizes of fathers and mothers are correlated with each other, due to a similar spatial knowledge and accessibility to various facilities. The daily variations in the travel time expenditure of parents are also assumed to be correlated because of daily household task allocation and joint household travel. Data collected from a three-week household travel diary in the Bandung Metropolitan Area in Indonesia are used for estimation in this study. The estimated frontier model component shows that neither parent has reached their maximum travel time budget and/or minimum travel time need that they inherently must spend. Compared with other attributes, the perceived accessibility attributes play the most important role in influencing the activity space limits. For households with fully employed fathers, a trade-off mechanism is found in travel time expenditure between parents, which is likely due to the redistribution of household tasks. On the other hand, for households with fathers who are not fully employed, a complementary effect is found, arising from the joint travel among household members. The travel time budget and activity space limits of fathers are positively correlated with those of mothers. These findings call for the formulation of transport policies that consider the household as a unit, especially in developing countries such as Indonesia, to fulfil the mobility needs of different market segments, e.g., households with fully employed fathers and those with fathers who are not fully employed.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): X.Y. Wang, S.L. Zhang, S.D. Feng, L. Qi, R.P. Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The structures of the Ti〈sub〉75〈/sub〉Al〈sub〉25〈/sub〉 alloy during rapid-quenching with and without external pressure are investigated by using molecular dynamic techniques. The amorphous phase can be obtained at the cooling rate 10.0 K/ps without pressure. The alloy is composed of crystal and amorphous phase at the cooling rate 0.1 and 1.0 K/ps without pressure, but the pure amorphous phase can be formed when the pressure exceeds the critical value. The critical pressure is about 20 and 30 GPa when the cooling rate is 0.1 and 1.0 K/ps, respectively. H-A indices analysis indicates that high pressure favors the formation of the ideal icosahedral structures in the amorphous Ti〈sub〉75〈/sub〉Al〈sub〉25〈/sub〉 alloy, and the content of 1551 bond-type can reach near to 50% when the pressure is 30 GPa. The amorphous state can be maintained if the external pressure is removed from the alloy step-by-step. The content of 1551 bond-type decreases with the deceasing of the pressure, but the 1541 and 1431 bond-types increase in this process.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Physics and Chemistry of Solids, Volume 124〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Yunli Zhang, Song Hu, Yingli Liu, Zhengjuan Wang, Wei Ying, Guohong Zhou, Shiwei Wang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A series of red-emitting Mn〈sup〉4+〈/sup〉 doped Lu〈sub〉3〈/sub〉Al〈sub〉5〈/sub〉O〈sub〉12〈/sub〉 (LuAG) ceramic phosphors were successfully prepared by a simple solid-state reaction method in a high-temperature muffle. MgO was co-doped as sintering aids and Mg〈sup〉2+〈/sup〉 ions helped to realize the charge balance. The relations between the luminescence properties, crystal structures and the microstructures were well established. Results indicated that MgO promoted the densification of the ceramics as the specimens’ relative densities were up to 99%. Moreover, the substitution of Al〈sup〉3+〈/sup〉 with Mg〈sup〉2+〈/sup〉 have changed crystal structures and further affected the luminescent properties. Overall, the obtained ceramic phosphors showed strong red-light emission under excitation of ultraviolet and blue light. By optimizing the Mg〈sup〉2+〈/sup〉 and Mn〈sup〉4+〈/sup〉 concentration, a quantum efficiency (QE) as high as 47.8% can be achieved under the excitation of 460 nm light, indicating that the LuAG: Mn〈sup〉4+〈/sup〉 ceramic phosphors are promising candidates for WLEDs applications.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): GuoShuai Qin, Xin Zhang, MingHao Zhao, Gang Wang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Herein, three-point bending testing of an edge-cracked specimen and finite element analysis were used to determine the fracture toughness of GaN piezoelectric semiconductive ceramics, and the effect of an applied electric current on the fracture properties of the GaN ceramics was investigated. The results indicated that an electric current has a significant effect on the fracture behavior of piezoelectric semiconductive ceramics. Specifically, the application of a relatively low electric current density (1.67 × 10〈sup〉4〈/sup〉 A m〈sup〉−2〈/sup〉) increased the fracture toughness by 36.8%, while further increases in electric current density reduced the fracture toughness. In addition, the electric current can lead to the ductile fracture of brittle GaN ceramics. Finally, the mechanisms behind these results were systematically analyzed. These findings are useful for designing more reliable GaN electromechanical devices.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Daniel Marinha, Manuel Belmonte〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Composites of 8 mol% Yttria-stabilized Zirconia (YSZ) containing 0, 7, 10 and 14 vol.% of graphene nano-platelets (GNP) were fully densified by Spark Plasma Sintering. The effect of GNP on the electrical performance of the composites was analyzed by impedance spectroscopy as a function of temperature (150–800 °C) and oxygen partial pressure (0.21–10〈sup〉−20〈/sup〉 atm). Results show that below GNP percolation threshold (7.1 vol.%), the electrical behavior is dominated by the matrix oxygen-ion conductivity. Above the threshold, the conductivity is predominantly electronic provided by the GNP network. The total conductivity of composites was used as an indicator of GNP stability in different atmospheres. YSZ/GNP composites remain stable in inert conditions up to 600 °C, and in reducing conditions up to 800 °C, making them good alternatives to perovskite-based materials used for electrochemical applications.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): T. Kolodiazhnyi, T. Charoonsuk, M. Spreitzer, N. Vittayakorn〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We report on magnetism, charge transport, dielectric properties and specific heat of Ce〈sub〉1−〈em〉x〈/em〉〈/sub〉Sb〈sub〉〈em〉x〈/em〉〈/sub〉O〈sub〉2〈/sub〉 ceramics sintered at 1650 〈sup〉∘〈/sup〉C with a final antimony content of 0 ≤ 〈em〉x〈/em〉 ≤ 0.0017. In contrast to other donor dopants, such as Nb, Ta, U and W, charge compensation of antimony in Ce〈sub〉1−〈em〉x〈/em〉〈/sub〉Sb〈sub〉〈em〉x〈/em〉〈/sub〉O〈sub〉2〈/sub〉 does not involve the formation of the Ce〈sup〉3+〈/sup〉 ions as revealed by the magnetic susceptibility data. Therefore, we conclude that antimony is mainly present as Sb〈sup〉3+〈/sup〉 ion and acts as an acceptor dopant in Ce〈sub〉1−〈em〉x〈/em〉〈/sub〉Sb〈sub〉〈em〉x〈/em〉〈/sub〉O〈sub〉2〈/sub〉. This conclusion is also supported by a very low electrical conductivity of the Sb-doped ceria that shows an activation energy 〈em〉E〈/em〉〈sub〉〈em〉σ〈/em〉〈/sub〉 ∼ 0.97 eV. This activation energy is close to that observed in oxygen conducting acceptor-doped ceria and is significantly higher than the typical 〈em〉E〈/em〉〈sub〉〈em〉σ〈/em〉〈/sub〉 ∼ 0.1–0.3 eV values reported for 〈em〉n〈/em〉-type CeO〈sub〉2〈/sub〉. Below 10 K, both an anomaly in the dielectric loss and a small specific heat surplus in Sb-doped ceria indicate a low-energy dipolar relaxation probably associated with a local dynamics of the off-centered Sb〈sup〉3+〈/sup〉 point defects.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Fei Zhang, Jérôme Chevalier, Christian Olagnon, Shuigen Huang, Wout Veulemans, Kim Vanmeensel, Jef Vleugels〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Slow crack growth (SCG) behavior of four zirconia-based composites reinforced with 40 vol% WC, TiC, NbC or TiCN were studied by means of double-torsion testing. Compared to monolithic zirconia, the composites had a higher resistance to fast fracture, i.e., higher fracture toughness. The extent of toughening depended on the reinforcement type, shifting the V-K〈sub〉I〈/sub〉 (crack velocity versus stress intensity factor) curve parallel to higher K〈sub〉I〈/sub〉 values. More importantly, these composites were less sensitive to SCG. Identical V-K〈sub〉I〈/sub〉/K〈sub〉IC〈/sub〉 curves with steeper slopes compared to monolithic zirconia were observed for the investigated composites, independent on the reinforcement type. No rising R-curve was measured, at least in the crack-size domain investigated by SCG. Therefore, the higher SCG resistance of the composites was due to the intrinsic stress-assisted corrosion resistance of the covalent non-oxide secondary phase.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Christian Thieme, Michael Kracker, Christian Patzig, Katrin Thieme, Christian Rüssel, Thomas Höche〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Glasses with the base composition 8 BaO·8 SrO·34 ZnO·50 SiO〈sub〉2〈/sub〉 were studied with respect to the crystallization of a phase with the composition Ba〈sub〉0.5〈/sub〉Sr〈sub〉0.5〈/sub〉Zn〈sub〉2〈/sub〉Si〈sub〉2〈/sub〉O〈sub〉7〈/sub〉. Some glasses were doped with gold and/or antimony oxide. All glasses exhibited solely surface crystallization. If the glasses contained both antimony and gold, they showed red coloration after different heat treatments and the crystal growth velocities were enhanced, depending on the chosen temperature, by around a factor of 30. Crystals were proven to be oriented statistically, while in all other glasses of the system under consideration, i.e., in those which did not contain both gold and antimony, an orientation of the crystals with their c-axes perpendicular to the surface was obtained. This effect is explained by a continuous nucleation in front of the growing crystals.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Dries Van Laethem, Johan Deconinck, Annick Hubin〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The ionic conductivity of acceptor doped ceria is strongly influenced by grain boundaries and interfaces. Most experiments show a decrease in ionic conductivity and an increase in electronic conductivity in these regions. Classical models explain this observation by the formation of space charge layers that are depleted of mobile ionic charge carriers and enriched in small polarons. However, some experiments demonstrate an increase in ionic conductivity and recent models show that the space charge layers can also be enriched in mobile ionic species. Because of these contradictions, it is still not clear whether nanocrystalline or thin film ceria can offer superior ionic conductivity or not. To aid this debate, we calculate the ionic conductivity of yttrium doped ceria in regions of net charge density using kinetic Monte Carlo simulations. Through an appropriate choice of the charge densities, these calculations allow to demarcate the possible conductivity gains from space charge layers.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Cell, Volume 175, Issue 4〈/p〉 〈p〉Author(s): Moshe Sade-Feldman, Keren Yizhak, Stacey L. Bjorgaard, John P. Ray, Carl G. de Boer, Russell W. Jenkins, David J. Lieb, Jonathan H. Chen, Dennie T. Frederick, Michal Barzily-Rokni, Samuel S. Freeman, Alexandre Reuben, Paul J. Hoover, Alexandra-Chloé Villani, Elena Ivanova, Andrew Portell, Patrick H. Lizotte, Amir R. Aref, Jean-Pierre Eliane, Marc R. Hammond〈/p〉 〈h5〉Summary〈/h5〉 〈div〉〈p〉Treatment of cancer has been revolutionized by immune checkpoint blockade therapies. Despite the high rate of response in advanced melanoma, the majority of patients succumb to disease. To identify factors associated with success or failure of checkpoint therapy, we profiled transcriptomes of 16,291 individual immune cells from 48 tumor samples of melanoma patients treated with checkpoint inhibitors. Two distinct states of CD8〈sup〉+〈/sup〉 T cells were defined by clustering and associated with patient tumor regression or progression. A single transcription factor, 〈em〉TCF7〈/em〉, was visualized within CD8〈sup〉+〈/sup〉 T cells in fixed tumor samples and predicted positive clinical outcome in an independent cohort of checkpoint-treated patients. We delineated the epigenetic landscape and clonality of these T cell states and demonstrated enhanced antitumor immunity by targeting novel combinations of factors in exhausted cells. Our study of immune cell transcriptomes from tumors demonstrates a strategy for identifying predictors, mechanisms, and targets for enhancing checkpoint immunotherapy.〈/p〉〈/div〉 〈h5〉Graphical Abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0092867418313941-fx1.jpg" width="375" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Nikolas Grünwald, Yoo Jung Sohn, Xiaoyan Yin, Norbert H. Menzler, Olivier Guillon, Robert Vaßen〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Dense protective layers are needed to reduce chromium-related degradation in SOFC stacks. In particular, atmospheric plasma sprayed (APS) Mn〈sub〉1.0〈/sub〉Co〈sub〉1.9〈/sub〉Fe〈sub〉0.1〈/sub〉O〈sub〉4〈/sub〉 (MCF) coatings demonstrated low degradation rates in stack tests. We show that short-term annealing in air induces crack healing within these coatings. Parallel to this effect, a phase transformation is observed originating from oxidation that proceeds by solid state-diffusion. The present contribution reveals the basic mechanisms of the microstructural and phase changes of coatings in long-term annealing tests of up to 10,000 h at 700 °C. The layer develops differently at the air-facing surface and in the bulk. Due to cation deficiency, oxidation is dominated by cation outward diffusion, leading to a Co-enriched surface layer. The bulk displays a fine distribution of the initial (rock salt) and the final (spinel) phases. Understanding the mechanisms leading to these irreversible changes enables predictions to be made concerning durable protectivecoatings in SOFCs.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Sana Algharaibeh, Anthony J. Ireland, Bo Su〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Highly aligned lamellar ceramic scaffolds were produced using a bi-directional freeze casting technique. A specially designed, sloped copper mould was covered with a polymer to modulate the temperature field. Effects of different processing parameters (cooling rate, mould slope angle, ceramic solid loading and binder concentration) on lamellar orientation were systematically studied. The results showed that freezing under a dual temperature gradient produced highly aligned ceramic scaffolds. Increasing both the cooling rate and the mould slope angle increased the size of the ordered ceramic region. Using different alumina solid loadings in the initial suspension had little effect on the aligned lamellar structure. Increasing the binder concentration affected ice crystal growth in a highly aligned direction. Therefore, freeze casting using a dual temperature gradient can be used to fabricate highly aligned porous materials.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Jörg Exner, Michael Schubert, Dominik Hanft, Jaroslaw Kita, Ralf Moos〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Aerosol deposition features the formation of dense and well adhering ceramic films directly at room temperature, without the need of any heat treatment during or after the deposition. While these claims are true for a 〈em〉suitable〈/em〉 ceramic powder, the success of the film deposition is highly dependent on the 〈em〉right〈/em〉 choice of the powder. Beside the commonly stated particle size that should be in the sub-micrometer to micrometer range, other influencing powder parameters exist, some of which have not yet been fully identified.〈/p〉 〈p〉In this work, ceria nanopowders were thermally pretreated and the quality of subsequent sprayed films was observed. A minimum crystallite size in the powder was determined in order to enable the underlying deposition mechanism. Furthermore, the conversion of kinetic particle energy to the formation of surface energy during impact was estimated. A first universal behavior is found leading to a recommendation for a suitable AD powder preparation.〈/p〉 〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Zhijian Sun, Lei Liu, Yuxiao Lu, Guangyue Shi, Jiajun Li, Lei Ma, Jie Zhao, Hongli An〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉NASION-type Li〈sub〉1.5〈/sub〉Al〈sub〉0.5〈/sub〉Ge〈sub〉1.5〈/sub〉(PO〈sub〉4〈/sub〉)〈sub〉3〈/sub〉(LAGP) is prepared by a novel sol-gel method using low cost inorganic germanium (GeO〈sub〉2〈/sub〉) as the precursor. The composition and phase transformation during the heating of the LAGP precursors are analyzed using thermogravimetric-differential scanning calorimetry (TG-DSC) and X-ray diffraction (XRD). The structures and morphologies of the LAGP are characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the LAGP annealed at 900 ℃ is partially crystallized and consists of a large number of nanoscale grains surrounded by amorphous regions. The LAGP particles present an irregular morphology with a large size distribution over a range of 0.2–1 μm. In addition, ionic conductivities of the prepared LAGP first increase and then decrease with an increase in the sintering temperature and time. A high ionic conductivity (4.18 × 10〈sup〉−4〈/sup〉Scm〈sup〉-1〈/sup〉) with an activation energy of 0.30 eV are obtained for the LAGP sample sintered at 900 °C for 8 h.〈/p〉〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volumes 467–468〈/p〉 〈p〉Author(s): S.P. Sun, J.L. Zhu, S. Gu, X.P. Li, W.N. Lei, Y. Jiang, D.Q. Yi, G.H. Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The surface stability and equilibrium morphology of MoO〈sub〉3〈/sub〉 were investigated by the first principles calculations. The thermodynamic energies of the stoichiometric surfaces of MoO〈sub〉3〈/sub〉 are in the order (0 1 0) 〈 (1 0 1) 〈 (0 0 1) 〈 (1 0 0). It is found that the (0 1 0) surface has a lowest surface energy, which agrees well with the previous calculations. The energies of the non-stoichiometric surfaces were evaluated as functions of temperature and oxygen partial pressure. The results show that the energies of Mo-terminated surfaces decrease with temperatures, and increase with oxygen partial pressures, while the energies of O-terminated surfaces show the opposite rule. The equilibrium morphology of MoO〈sub〉3〈/sub〉 was predicted by using the Gibbs-Wulff model, and then was compared with the other’s experiments and theoretical results.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volumes 467–468〈/p〉 〈p〉Author(s): Sanju Gupta, Nicholas Dimakis〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The interfacial interactions between transition metal oxides (vanadium oxide VO〈sub〉2〈/sub〉, vanadium pentoxide V〈sub〉2〈/sub〉O〈sub〉5〈/sub〉, cobalt oxide CoO and Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉, manganese oxide MnO〈sub〉2〈/sub〉) and water adsorbates on graphene supports as solvated interfaces and influence of defects in graphene are studied using periodic density functional theory (DFT) calculations in view of their significance for applied electrochemistry. DFT complemented and synergized our experimental work. The optimized metal oxide adatom-graphene geometries identified the preferred adatom sites, whereas metal oxide-graphene strengths are correlated with the adatom distance from the graphene plane, the Metal-C overlap populations, and the adsorption energies. The presence of finite electronic density of states (DOS) near Fermi level and charge transfers between the adatom top layer and graphene supports reflect primarily covalent bonding nature. The presence of small orbital overlap integral of bonds between the s and p (and d) orbitals of the nearest carbon (graphene), carbon oxide (graphene oxide) and metal oxide atoms reveal localized orbital re-hybridization resulting in changes in DOS yielding high electrochemical activity. Moreover, for increased adatom coverage the extent of charge transfer reverses resulting in limited electroactivity. In fact, DFT calculations are corroborated with experimental findings, where graphene-based supports decorated with optimal mass loaded nanostructured Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 and MnO〈sub〉2〈/sub〉 (as well as V〈sub〉2〈/sub〉O〈sub〉5〈/sub〉) were capable of delivering maximum specific energy storage capacity (C〈sub〉s〈/sub〉) 〉 550 F·g〈sup〉−1〈/sup〉 (Gupta et al. J. Mater. Res. 32, 301 (2017)) in contrast to higher or lower loading. The presence of defects in graphene materials results in new electronic states to endow unique functionalities that is not otherwise possible in the bulk and with adsorbed water molecules besides optimum C/O ratio in graphene oxide nanosheets that show redshift thus a decreasing bandgap and finite charge transfer from graphene to water molecules. The case examples studied in this work represent a first glimpse of what may become routine and integral step in materials design and discovery for alternative energy and sustainable environmental technologies.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 25 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Catalysis A: General, Volume 570〈/p〉 〈p〉Author(s): Wooyoung Kim, Wookyun Shin, Kyoung Jun Lee, YongSeok Cho, Hyung Soon Kim, Igor N. Filimonov〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Characterization of acid-base centers and catalytic dehydration of 2,3-butanediol (BDO) was performed over a wide range of silica-supported alkali phosphates (M_P/SiO〈sub〉2〈/sub〉; M = Na, K, Cs; M:P = 0.5–3 mol:mol). Selectivity to 1,3-butadiene (BD) and 3-butene-2-ol (3B2OL) formed by elimination correlates with the densities of conjugated acid-base pairs and increases in the order Na 〈 K ≈ Cs. Selectivity to 2,3-epoxybutane (BTO) formed by dehydrative epoxidation increases with the M/P ratio in the order Na 〈 K ≤ Cs. Methyl ethyl ketone (MEK) and isobutyraldyde (IBA) formed by the rearrangement are produced by isolated Brønsted acid centers. Conjugated acid-base pairs are probably composed of the end groups of polyphosphates having both acid P-OH and base P〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉O〈sup〉−〈/sup〉⋯M〈sup〉+〈/sup〉 moieties. Isolated Brønsted acid centers are probably silica grafted phosphoric acid molecules at low M/P and 〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉PO(OH)〈sub〉2〈/sub〉 end groups of oligophosphates at M/P 〉 1.5.〈/p〉 〈p〉Deactivation rate increases with the increase of M/P ratio in order Na 〈 K 〈 Cs. Deactivation patterns imply that sites responsible for elimination are active in dehydrative epoxidation. Dehydration of 3B2OL smoothly proceeds to BD, but the catalysts deactivate faster compared to BDO dehydration.〈/p〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0926860X18304095-ga1.jpg" width="491" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): Anne-Isabelle Bidegaray, Andrea Ceglia, Maria Rita Cicconi, Van-Thai Pham, Amandine Crabbé, El Amine Mernissi Cherigui, Karin Nys, Herman Terryn, Daniel R. Neuville, Stéphane Godet〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The analysis of iron, manganese and antimony in silicate glass is of great interest in chemistry, materials science, earth sciences and archaeological sciences. Yet, conclusions from different fields appear to be contradictory and many questions about redox reactions in glass remain. The purpose of this study is thus to discuss whether and how these multivalent elements interact in glass. Soda-lime silicate melts containing iron along with manganese and/or antimony have been analysed at different high temperatures under argon atmosphere. Using 〈em〉in-situ〈/em〉 XANES at the Fe K-edge, redox thermodynamics, kinetics and diffusivities have been assessed for the different compositions. The data obtained show that antimony is more efficient at oxidising iron compared to manganese at all temperatures. The oxidising power trend would thus be Sb 〉 Sb + Mn 〉 Mn. Furthermore, hypotheses on the formation of Fe-Mn complexes are also reported in glasses with stoichiometric proportions of iron and manganese. Based on the determination of redox diffusivities, it appears that presence of other multivalent elements does not significantly affect the iron redox mechanisms and that diffusivity is essentially controlled by the mobility of calcium.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): Wentao Zhang, Feng He, Junlin Xie, Xiaoqing Liu, De Fang, Hu Yang, Zhihong Luo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Glass ceramics from modified molten blast furnace (BF) slag were prepared. The crystallization behavior of the modified BF slag was characterized using differential thermal analysis (DTA), X-ray diffraction (XRD), and field emission scanning electron microscope (FESEM). The crystallization kinetics results indicated that the crystallization activation energy initially decreased and subsequently increased with increasing CaO/SiO〈sub〉2〈/sub〉. The crystallization temperature and the crystallization index (n) decreased from 916 to 867 °C, and 5.66–1.13, respectively. The crystallization mechanism transformed from bulk crystallization to surface crystallization. By XRD analyzing, Melilite was developed as the main crystal phase, and the transformation of crystal from akermanite to gehlenite was observed. The rapid surface crystallization was beneficial for maintaining the shape of glass ceramics. The complex replacement in melilite crystals resulted in the micro cracks in glass ceramics, therefore led to the decrease of flexural strength of glass ceramics〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): B.C. Jamalaiah〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Different amounts of GeO〈sub〉2〈/sub〉 activated tellurite tungstate glasses were prepared by melt quenching technique. Thermal stability and glass forming ability were studied using differential scanning calorimetry. The chemical composition, homogeneity and amorphous nature of studied glasses were investigated. The phonon energy was estimated to be 721.34 cm〈sup〉−1〈/sup〉. Experimentally determined refractive indices were compared with those determined from optical band gap (E〈sub〉g〈/sub〉) and optical electronegativity (Δ〈em〉χ〈/em〉〈sup〉∗〈/sup〉). The dielectric constant (K) and electronic polarizability (α) were determined using refractive index value. The presence of disorder was estimated in terms of Urbach energy (E〈sub〉U〈/sub〉). The average electronegativity (〈em〉χ〈/em〉〈sub〉〈em〉ave〈/em〉〈/sub〉), oxide ion polarizability (〈em〉α〈/em〉〈sub〉〈em〉O〈/em〉〈/sub〉〈sup〉2−〈/sup〉) and covalent character (C〈sub〉cov〈/sub〉) were determined. The content of GeO〈sub〉2〈/sub〉 was optimized to be 10.0 mol% to design a novel host material for solid state lasers and fiber devices.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): Chunhe Jiang, Kejiang Li, Jianliang Zhang, Qinghua Qin, Zhengjian Liu, Minmin Sun, Ziming Wang, Wang Liang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉SiO〈sub〉2〈/sub〉-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉-CaO-MgO is the most significant slag system in the blast furnace ironmaking process and it is very important to investigate the microstructure and viscosity of the system. In this paper, molecular dynamics simulations were carried out to explore the effects of MgO/Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 ratio on structure and properties of the system. Based on the self-diffusion coefficients, the viscosities were calculated by Einstein-Stokes equation and compared with the experimental value and the Factsage value. The results showed that with the increase of MgO/Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 ratio, the stability of [SiO〈sub〉4〈/sub〉]〈sup〉4−〈/sup〉 and [AlO〈sub〉4〈/sub〉]〈sup〉5−〈/sup〉 tetrahedron became weaken and the relative proportions of bridge and non-bridge oxygen showed a decrease. And due to the increase of MgO, more Mg〈sup〉2+〈/sup〉 ions are used as network modifiers to reduce the degree of polymerization of the system, resulting in a decrease in the viscosity, which is consistent with experimental results. Finally, based on the present study, in the case of increasing Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 content of blast furnace slag, the fluidity of slag could be adjusted by controlling MgO/Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 ratio, thereby providing a basis for stable operation of blast furnace ironmaking.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): A.I. Popov〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The definition of glassy state presented by the authors of the article “The glassy state of matter: Its definition and ultimate fate” E. Zanotto and J. Mauro is considered. The importance of the contribution to the glassy state problem made in the article is emphasized. At the same time consideration of the glassy state as unstable state of matter causes definite objections. It is more correctly to consider the glassy state as metastable state of matter.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): M.G. Syamala Rao, M.A. Pacheco-Zuñiga, L.A. Garcia-Cerda, G. Gutiérrez-Heredia, J.A. Torres Ochoa, M.A. Quevedo López, R. Ramírez-Bon〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, we developed a novel inorganic-organic hybrid gate dielectric by combining zirconium and hafnium components to form zirconium hafnium oxide strongly linked with polymethyl methacrylate (ZrHfO〈sub〉2〈/sub〉-PMMA) and deposited at low temperature (200 °C) by sol-gel method. The obtained 108 nm thick, high-quality hybrid gate dielectric showed an exceptionally low surface roughness (0.9-nm), a low leakage current density (7.7 × 10〈sup〉−6〈/sup〉 A/cm〈sup〉2〈/sup〉) and reasonable dielectric properties such as gate capacitance along with dielectric constant (77 nF/cm〈sup〉2〈/sup〉 & 9.4 @1 kHz) respectively. To examine the ZrHfO〈sub〉2〈/sub〉-PMMA hybrid dielectric electrical properties we constructed thin-film transistors (TFTs) with room temperature r.f sputtered n-type metal oxide semiconductors, a-IGZO and ZnO, as active channels. The bottom gate fabricated a-IGZO TFTs driving at as low as below 6 V, with extracted field effect mobility of 2.45 cm〈sup〉2〈/sup〉/V. s, a low threshold voltage of 1.2 V with large ON/OFF current ratio 10〈sup〉7〈/sup〉 respectively. On the other hand, for comparison we employed ZnO TFTs by applying same hybrid dielectric system, the obtained parameters of bottom gate ZnO TFTs were good field effect saturation mobility of 12.8 cm〈sup〉2〈/sup〉/V. s, threshold voltage of 1.8 V and ON/OFF current ratio of 10〈sup〉3〈/sup〉.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): Weidi Zhu, Mark Lockhart, Bruce Aitken, Sabyasachi Sen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The viscoelastic properties of supercooled As〈sub〉x〈/sub〉Se〈sub〉100-x〈/sub〉 (0 ≤ x ≤ 30) and As〈sub〉x〈/sub〉Se〈sub〉100-x-y〈/sub〉I〈sub〉y〈/sub〉 (x = 20, 30 and y = 10, 20) liquids are studied using oscillatory parallel plate rheometry. In addition to the α-relaxation process, the shear relaxation of liquids with selenium chains longer than ~ 3 atoms is also characterized by a low-frequency polymeric mode. The temporal decoupling of this low-frequency soft/floppy relaxation mode from that of the α-relaxation mode is a unique function of the average selenium chain length. The floppy mode abruptly vanishes for liquids with average chain lengths shorter than ~ 3 Se atoms, thus implying a dynamical rigidity transition. When taken together, these results indicate that, contrary to the conventional wisdom, the pertinent structural variable associated with such transition in the viscoelastic behavior is not the average coordination number but instead the intermediate-range structural elements such as the average selenium chain length.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 502〈/p〉 〈p〉Author(s): M.S.A. Mohd Saidi, S.K. Ghoshal, K. Hamzah, R. Arifin, M.F. Omar, M.K. Roslan, E.S. Sazali〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We report the influence of silver (Ag) and titania (TiO〈sub〉2〈/sub〉) nanoparticles (ATNPs) co-embedment on the photoluminescence (PL) properties of dysprosium ions (Dy〈sup〉3+〈/sup〉) doped zinc-magnesium tellurite glass system prepared using conventional melt quenching method. Both up- and down- converted PL spectra of glasses revealed three emission bands located at 482 (blue: 〈sup〉4〈/sup〉F〈sub〉9/2〈/sub〉 → 〈sup〉6〈/sup〉H〈sub〉15/2〈/sub〉), 574 (yellow: 〈sup〉4〈/sup〉F〈sub〉9/2〈/sub〉 → 〈sup〉6〈/sup〉H〈sub〉13/2〈/sub〉) and 664 nm (weak red: 〈sup〉4〈/sup〉F〈sub〉9/2〈/sub〉 → 〈sup〉6〈/sup〉H〈sub〉11/2〈/sub〉), where the band intensities were enhanced with the inclusion of ATNPs. Glasses with 0.2 mol% of ANPs and up to 0.3 mol% of TNPs disclosed highest PL intensity enhancement, which was majorly attributed to the ATNPs mediated localized surface plasmon resonance (LSPR) and large field enhancement (called hot spot) effects in the proximity of Dy〈sup〉3+〈/sup〉 ions. Absorption spectra of glasses displayed two plasmon bands characteristics of each type of nanoparticle. It was inferred that the superposition of localized SP modes from ATNPs could generate new hybridized modes (strong local field in the vicinity of Dy〈sup〉3+〈/sup〉 ions) shifted with respect to the single type of NPs resonance. HRTEM images showed the existence of both Ag and titania NPs inside the glass matrix. Glasses containing ATNPs exhibited anatase phase with (103) and (112) nanocrystalline lattice plane orientation. Proposed glass system may be useful for the development of solid state laser and photonic devices.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Dapeng Zhou, Jürgen Malzbender, Yoo Jung Sohn, Olivier Guillon, Robert Vaßen〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉During the last decade, Suspension Plasma Spraying (SPS) attracted a lot of interest as an alternative process to produce columnar Thermal Barrier Coatings (TBCs). In this study, columnar TBCs were deposited with SPS. After spraying, samples were isothermally annealed at 1373 K for 1 h, 3 h, 10 h and 50 h, respectively. Microstructures and mechanical properties of the ceramic coatings were investigated as a function of annealing time. Annealing resulted in healing of micro-cracks, coarsening of pores, growth of domain size, companied with a decrease of porosity within columns. The change of coating microstructure led to change of mechanical properties. In addition, residual stress in SPS coatings was also investigated. Furthermore, as-sprayed coatings and pre-annealed coatings were subjected to burner rig tests. Short time pre-annealing allowed to enhance thermal cycling lifetime of such SPS coatings. The thermal cycling results were related to microstructure modifications of coatings.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Xuejin Yang, Bin Li, Duan Li, Changwei Shao, Changrui Zhang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In order to improve the high-temperature performance of wave-transparent materials especially for the high-speed aircrafts application, filament winding combined with sol-gel method was adopted to the fabrication of unidirectional silicon nitride fiber reinforced silica matrix composites. The mechanical properties and the interface evolution at high temperatures were investigated. The results show that the composite sintered in N〈sub〉2〈/sub〉 maintains a flexural strength of 210MPa at up to 1200°C, while its counterpart prepared in air experiences a dramatic reduction to about 73MPa. The degradation is due to the partial oxidation of silicon nitride fibers at the fiber matrix interface. Besides, it is also notable that the bending strength of these two composites undergoes a similar growth from about 160 to 210MPa when tested under 900°C, which can be explained by the release of thermal stress on the silicon nitride fibers.〈/p〉〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Magnetism and Magnetic Materials, Volume 474〈/p〉 〈p〉Author(s): Muhammad Arshad, M. Asghar, Muhammad Junaid, Muhammad Farooq Warsi, M. Naveed Rasheed, M. Hashim, M.A. Al-Maghrabi, Muhammad Azhar Khan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study Co-Ni co-doped nanocrystalline manganese ferrites were fabricated via co-precipitation method. The annealing of as prepared nanoferrites was done at 950 °C for 7 h. The powder X-ray diffraction (XRD) confirmed that all samples possessed cubic spinel structure. The crystallite size was determined by Scherrer’s equation that lies in the range of 27–35 nm. The spectral analysis confirmed bending and stretching of bonds at octahedral (B) and tetrahedral (A) sites. The spectral bands were shifted towards the longer wavelength side and these indicate the incorporation of dopants cations (Co-Ni). The magnetic parameters were measured from the M-H loops of nanoferrites. With the increase of Co-Ni contents, the saturation magnetization (Ms) increased up to x = 0.15 and then it decreased. The dielectric properties of all compositions were studied in 1 MHz–3 GHz range and were discussed in the light of Debye-type reduction phenomenon by following the Koop’s theory. The dielectric and magnetic behavior evaluation suggested that synthesized ferrites are suitable for microwave devices fabrication.〈/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-S0304885318319127-ga1.jpg" width="282" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Wei Hao, Qihui Zhang, Chen Xing, Fangwei Guo, Meiyu Yi, Xiaofeng Zhao, Ping Xiao〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Y〈sub〉2〈/sub〉SiO〈sub〉5〈/sub〉 is a promising material for the thermal barrier coatings due to its low thermal conductivity, high temperature stability and exceptional resistance for molten silicate attack. However, it suffers low fracture toughness and low coefficient of thermal expansion compared with yttria-stabilized zirconia (YSZ). In this study, a composite coating approach, i.e., incorporating YSZ into Y〈sub〉2〈/sub〉SiO〈sub〉5〈/sub〉 coating, was employed to overcome those limitations. The double-layered Y〈sub〉2〈/sub〉SiO〈sub〉5〈/sub〉-YSZ/YSZ coatings were fabricated using atomospheric plasma spraying and tested under thermal cycling at 1150 °C. The phase compositions, microstructure, mechanical properties and the failure behavior were evaluated. It was found that the amorphous phase during spraying would crystallize at high temperature accompanied by volume shrinkage, leading to cracks and spallation in the coating. With YSZ addition, the composite coatings exhibited a much longer lifetime than the single phase Y〈sub〉2〈/sub〉SiO〈sub〉5〈/sub〉 coating due to a lower volume shrinkage and enhanced toughness.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Jian Xu, Baofu Hu, Chao Xu, Jian Wang, Bingguo Liu, Hui Li, Xinliang Wang, Baoli Du, Yuxuan Gong〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Good thermal dispersion is essential for phosphors used in laser-lighting applications. Luminescent films naturally show better thermal dispersion than bulk phosphor because the distance to the supporting substrate is shorter, which facilitates heat dissipation. However, the underlying mechanism for luminescence saturation in films is still unclear. In addition, the synthesis of luminescent films always involves the use of carbon-rich organic materials, which can introduce both pores and carbon residues. Here, we present a facile sol–gel route to synthesize YAG:Ce thick films suitable for laser lighting applications. Inorganic aluminum hydroxides are used as gelling agent, which solves the carbon residue problem. A series of YAG:Ce films of different thicknesses was produced at relatively low temperature (975 °C). The YAG:Ce film shows no luminescence saturation under 4.1 W blue laser excitation. This means this approach represents a strong potential candidate for applications like automotive headlamps and many other devices.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): João Vitor Campos, Isabela Reis Lavagnini, Rafael Vieira de Sousa, Julieta Adriana Ferreira, Eliria Maria de Jesus Agnolon Pallone〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Heterogeneous grain size distributions due to cathodic reduction of samples sintered by flash sintering (FS) are a recurring problem. Herein, we present an experimental setup for FS with refined control of the process parameters, especially the electric current density, to control the power peak that could reduce the grain size heterogeneity of sintered materials. The real-time control of the equipment enabled the development of a Multi-Step Flash Sintering (MSFS) process. This technique involves varying the maximum current density at the onset of the abrupt shrinkage of the sample during the flash phenomenon, smoothing the shrinkage and power density curves, avoiding power peak and allowing its control in real time. Tetragonal stabilised zirconia (3YSZ) was sintered in this equipment by both FS and MSFS. Preliminary results of this study were promising in terms of density control and improvement of grain size homogeneity.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Kang Guan, Haitao Ren, Qingfeng Zeng, Zhiqiang Feng, Jianqing Wu, Zhenya Lu, Pinggen Rao, Yangfang Cheng, Zhenyuan Gong, Yougen Yu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Porous ceramics are numerically constructed based on the convexity of the void phase: microstructures with convex pores are representative of isolated or randomly overlapping spherical pores, while particulate materials with non-convex pores are composed of randomly overlapping, partial overlapping or partially sintered solid spheres. Finite element simulations show that, given the porosity, thermal conductivities and elastic moduli for convex porosity are larger than the values for non-convex pores. These conditions are not well described by solely porosity. By contrast, this study proposes a new microstructural parameter, 〈lp2〉/(〈ls2〉+〈lp2〉), to estimate thermal conductivities and elastic moduli for both convex and non-convex pores. 〈ls2〉 and 〈lp2〉 are respectively mean-square solid chord length and mean-square pore chord length of cross-sections, which can be conveniently extracted from SEM images combined with chord length distributions of solid and void.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Tianrang Yang, Hailei Zhao, Mengya Fang, Konrad Świerczek, Jie Wang, Zhihong Du〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉La〈sub〉9.67〈/sub〉Si〈sub〉6-x〈/sub〉Cu〈sub〉x〈/sub〉O〈sub〉26.5-x〈/sub〉 (LSC, x = 0, 0.1, 0.3 and 0.5) are synthesized by a citric-nitrate method. Substitution Si with Cu promotes the densification process of silicate apatite. Unit cell parameters and volume increase linearly with Cu content. The Rietveld refinement reveals a much more distorted (Si,Cu)O〈sub〉4〈/sub〉 tetrahedra in the oxygen stoichiometric La〈sub〉9.67〈/sub〉Si〈sub〉5.5〈/sub〉Cu〈sub〉0.5〈/sub〉O〈sub〉26〈/sub〉 sample. The structural observation from high temperature XRD implies a second-order phase transition in La〈sub〉9.67〈/sub〉Si〈sub〉5.5〈/sub〉Cu〈sub〉0.5〈/sub〉O〈sub〉26〈/sub〉. Cu-doping decreases the activation energy of oxygen ion conduction and increases the conductivity of LSC materials in the temperature range of 550–800 °C. La〈sub〉9.67〈/sub〉Si〈sub〉5.5〈/sub〉Cu〈sub〉0.5〈/sub〉O〈sub〉26〈/sub〉 shows the conductivity values of 29.3 and 12.3 mS cm〈sup〉−1〈/sup〉 at 800 °C and 650 °C, respectively. The oxygen ion transference number of La〈sub〉9.67〈/sub〉Si〈sub〉5.5〈/sub〉Cu〈sub〉0.5〈/sub〉O〈sub〉26〈/sub〉 is higher than 0.99. These attractive properties make the La〈sub〉9.67〈/sub〉Si〈sub〉5.5〈/sub〉Cu〈sub〉0.5〈/sub〉O〈sub〉26〈/sub〉 a promising oxygen ion conducting electrolyte for applications of solid oxide fuel cells, oxygen sensors, oxygen separation membranes, 〈em〉etc.〈/em〉〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Hai Jiang, Xiao-Hong Wang, Wen Lei, Gui-Fen Fan, Wen-Zhong Lu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The effects of two-step sintering on the microstructure, mechanical and thermal properties of aluminum nitride ceramics with Yb〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 and YbF〈sub〉3〈/sub〉 additives were investigated. AlN samples prepared using different sintering methods achieved almost full density with the addition of Yb〈sub〉2〈/sub〉O〈sub〉3〈/sub〉–YbF〈sub〉3〈/sub〉. Compared with the one-step sintering, the grain sizes of AlN ceramics prepared by the two-step sintering were limited, and the higher flexural strength and the larger thermal conductivity were obtained. Moreover, the electrochemical impedance spectroscopy of AlN ceramic was associated with thermal conductivity by analyzing the defects and impurities in AlN ceramics. The fitting grain resistance and the activation energy for the grain revealed the lower concentrations of aluminum vacancy in the two-step sintered AlN ceramics, which resulted in the higher thermal conductivity. Thus, mechanical and thermal properties for AlN ceramics were improved with Yb〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 and YbF〈sub〉3〈/sub〉 additives sintered using two-step regimes.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Gregory N. Morscher, Ryan Maxwell〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Acoustic emission, electrical resistance, and surface optical techniques were used to monitor matrix cracking and fiber-breakage during fatigue in tension for [0/90]2s SiC-based laminate composite single-notch specimens. Acoustic emission sensors were positioned in several locations including on the edge of the specimen which enabled location of events through the width and the location of internal tunnel-type cracks. Surface optical techniques, including digital image correlation, enabled the extent of surface crack growth. From these two sets of data a simple circuit could be constructed of the different damaged and undamaged regions in the region of the notch that was in good agreement with the change in electrical resistance, thus establishing a correlation with change in ER and damage development. The unique placement of AE sensors on the edge of the specimen also enabled the capture and location of what are believed to be fiber failure events prior to ultimate failure.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Iñigo Garbayo, Federico Baiutti, Alex Morata, Albert Tarancón〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉New emerging disciplines such as Nanoionics and Iontronics are dealing with the exploitation of mesoscopic size effects in materials, which become visible (if not predominant) when downsizing the system to the nanoscale. Driven by the worldwide standardisation of thin film deposition techniques, the access to radically different properties than those found in the bulk macroscopic systems can be accomplished. This opens up promising approaches for the development of advanced micro-devices, by taking advantage of the nanostructural deviations found in nanometre-sized, interface-dominated materials compared to the “ideal” relaxed structure of the bulk. A completely new set of functionalities can be explored, with implications in many different fields such as energy conversion and storage, or information technologies. This manuscript reviews the strategies, employed and foreseen, for engineering mass transport properties in thin film ceramics, with the focus in oxide ionic and mixed ionic-electronic conductors and their application in micro power sources.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Christoph Settgast, Yvonne Ranglack-Klemm, Jana Hubalkova, Martin Abendroth, Meinhard Kuna, Horst Biermann〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Open-cell ceramic foams are used as filters in casting processes of molten metal to reduce the amount of non-metallic inclusions. These filters are exposed to high temperatures and loadings, sometimes for a longer time. Therefore, the dimensional stability has to be considered, which suffers from inelastic deformations, in particular creep deformations.〈/p〉 〈p〉A recent work of the authors describes the creep deformation behaviour of such foam structures using an experimental-numerical approach based on bulk material creep tests. Now, the results of this prediction are validated by creep curves of real foam samples. This comparison shows a good accordance for the considered parameters (load, temperature, time, and creep phase).〈/p〉 〈p〉Moreover, the influences of different structural parameters on the elastic foam stiffness and foam creep resistance are investigated. The relative foam density has the greatest impact, followed by uniaxial pore stretching in one direction and strut shape, whereas polydispersity has only a very small effect.〈/p〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Infrared Physics & Technology, Volume 96〈/p〉 〈p〉Author(s): Chunyan Guo, Yaoyao Sun, Qingxuan Jia, Zhi Jiang, Dongwei Jiang, Guowei Wang, Yingqiang Xu, Tao Wang, Jinshou Tian, Zhaoxin Wu, Zhichuan Niu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A kind of wide spectrum infrared detectors based on InAs/GaSb type-II superlattices (T2SLs) operating from 0.5 μm to 5 μm wavelength range is reported. The materials were grown by Molecular Beam Epitaxy (MBE) on GaSb substrates. Diverse types and sizes microstructure are fabricated on the surface of the detector to form the photon traps (PTs) array. PTs decrease the reflectivity and increase the light absorption of epitaxial material. Compared with the planar mesa detectors without antireflection (AR) film, detectors with PTs array exhibits a high responsivity of 0.86 A/W at 1160 nm and maximum D* reaches to 10〈sup〉9〈/sup〉 cm Hz〈sup〉1/2〈/sup〉/W in visible wavelength. Also, the PTs processed on detector augment spectral response and QE in infrared wavelength. The peak responsivity of the detector with PTs is to 1.35 A/W and QE can exceed to 0.76 in the infrared wavelength. The infrared detector with PTs is attractive for numerous applications.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Yong-Hyeon Kim, Young-Wook Kim, Kwang-Young Lim, Seoung-Jae Lee〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Two different SiC ceramics with a new additive composition (1.87 wt% Y〈sub〉2〈/sub〉O〈sub〉3〈/sub〉–Sc〈sub〉2〈/sub〉O〈sub〉3〈/sub〉–MgO) were developed as matrix materials for fully ceramic microencapsulated fuels. The mechanical and thermal properties of the newly developed SiC ceramics with the new additive system were investigated. Powder mixtures prepared from the additives were sintered at 1850 °C under an applied pressure of 30 MPa for 2 h in an argon or nitrogen atmosphere. We observed that both samples could be sintered to ≥99.9% of the theoretical density. The SiC ceramic sintered in argon exhibited higher toughness and thermal conductivity and lower flexural strength than the sample sintered in nitrogen. The flexural strength, fracture toughness, Vickers hardness, and thermal conductivity values of the SiC ceramics sintered in nitrogen were 1077 ± 46 MPa, 4.3 ± 0.3 MPa·m〈sup〉1/2〈/sup〉, 25.4 ± 1.2 GPa, and 99 Wm〈sup〉−1〈/sup〉 K〈sup〉−1〈/sup〉 at room temperature, respectively.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Weizeng Yao, Jialiang Zhang, Xuemei Wang, Chunming Zhou, Xue Sun, Jie Zhan〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Research for high-performance lead-free piezoelectric materials has become an urgent issue from the environmental concern. Very limited attempts on two-step sintering had been made so far. In this study, (K〈sub〉0.45〈/sub〉Na〈sub〉0.55〈/sub〉)〈sub〉0.98〈/sub〉Li〈sub〉0.02〈/sub〉Nb〈sub〉0.76〈/sub〉Ta〈sub〉0.18〈/sub〉Sb〈sub〉0.06〈/sub〉O〈sub〉3〈/sub〉 ceramics were prepared by both conventional sintering and two-step sintering. Piezoelectric properties, microstructure and domain structure were found to change significantly with sintering methods and sintering conditions. Two-step sintering was performed in the way that temperature is first quickly raised to 1180 °C, kept for 1 min, then immediately cooled down to 1120 °C and maintained for a desired time length. The effects of dwelling time on piezoelectric performance and microstructure as well as domain structure were investigated. High piezoelectric properties of 〈em〉d〈/em〉〈sub〉33〈/sub〉 = 455 pC/N, 〈em〉k〈/em〉〈sub〉p〈/sub〉 = 0.54 and 〈em〉k〈/em〉〈sub〉33〈/sub〉 = 0.67 were obtained in a ceramic prepared under the dwelling time of 20 h. This ceramic also possesses a very good piezoelectric thermal-ageing stability over −50 °C–150 °C. Further investigation reveals that this ceramic has a quite uniform grain-size distribution with the average grain size of about 12 μm in microstructure and shows domain patterns of simple parallel stripes with a hierarchical nanodomain structure appearing inside some of broad stripes. The observed excellent piezoelectric performance is considered to associate closely with the unique domain structure.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Ingo Jürgen Markel, Jürgen Glaser, Martin Steinbrück, Hans Jürgen Seifert〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A Si-C-N ceramic was synthesized by pyrolysis of the polysilazane Ceraset〈sup〉®〈/sup〉 PSZ 10 and PSZ 20. The preceramic polymer was crosslinked by gradual heating up to 300 °C and pyrolyzed at temperatures from 1000 °C to 1500 °C in flowing Ar- and N〈sub〉2〈/sub〉-containing atmospheres, respectively. The influence of the pyrolysis temperature and the nitrogen partial pressure (p〈sub〉N2〈/sub〉) on the high-temperature stability, phase reactions and crystallization behavior was investigated by STA, XRD and SEM/EDX. Additionally, gaseous pyrolysis- and reaction products were analyzed by on-line mass spectrometry. The CALPHAD (CALculation of PHAse Diagrams) method was used to calculate pyrolysis products and high-temperature phase stabilities as a function of temperature and p〈sub〉Ar〈/sub〉/p〈sub〉N2〈/sub〉. It is shown that the observed experimental findings are quantitatively confirmed and explained by the modelling.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Florimond Delobel, Sébastien Lemonnier, Élodie Barraud, Julien Cambedouzou〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The influence of Spark Plasma Sintering pressure and temperature on the evolution of the phase composition of two sources of 〈em〉β〈/em〉-SiC ceramic were studied based on X-ray diffraction and Raman scattering measurements. A commercial powder and a powder derived from a preceramic polymer precursor were chosen, and the investigation was undertaken in the [1850-2200 °C] temperature range and in the [17–127 MPa] pressure range. Analyses revealed that the 3C-6H phase transition depends on sintering pressure, which is shown to stabilize the cubic phase. The stability domains of the cubic phase as a function of sintering P and T were determined for both powdery precursors and revealed that the cubic phase stability is also linked to the nature of powdery precursor and in particular to its crystallinity state. The improvement of cubic phase stability at higher temperature by applying pressure allows sintering 〈em〉β〈/em〉-SiC ceramic with high density.〈/p〉〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Branislav Dzepina, Daniel Balint, Daniele Dini〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The incorporation of an efficient contact mechanics algorithm into a phase field sintering model is presented. Contact stresses on the surface of arbitrarily shaped interacting bodies are evaluated and built into the model as an elastic strain energy field. Energy relaxation through deformation is achieved by diffusive fluxes along stress gradients and rigid body motion of the deforming particles maintain contact between the particles. The proposed model is suitable for diffusion deformation mechanisms occurring at stresses below the yield strength of a defect-free material; this includes Nabarro-Herring creep, Coble creep and pressure-solution. The effect of applied pressure on the high pressure-high temperature (HPHT) liquid phase sintering of diamond particles was investigated. Changes in neck size, particle coordination and contact flattening were observed. Densification rates due to the externally applied loads were found to be in good agreement with a new theory which implicitly incorporates the effect of applied external pressure.〈/p〉〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 International Journal of Heat and Mass Transfer, Volume 130〈/p〉 〈p〉Author(s): Shengxiang Deng, Changda Nie, Haojie Jiang, Wei-Biao Ye〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Embedded fin in phase change materials (PCMs) is one of the most efficient methods to enhance the heat transfer between the PCM and heat transfer fluid (HTF). An appropriate arrangement of the fins plays significant role to design a highly efficient latent heat thermal energy storage (LHTES) unit. The aim of this study is to find the most efficient arrangement of fins to accelerate the charging rate. A two-dimensional numerical model based on finite volume method (FVM) was developed with considering natural convection and the calculation results were validated with experimental data. The heat transfer characteristics of LHTES unit with different fins arrangements were firstly explored. These include no fins, straight fins, angled fins, lower fins and upper fins. Then, the effects of fins number (〈em〉N〈/em〉), dimensionless fins length (〈em〉l〈/em〉), heat transfer fluid temperature (〈em〉T〈/em〉〈sub〉w〈/sub〉) and outer tube material on melting performance for four arrangements were studied. In addition, the best type of arrangements to increase the efficiency of heat exchanger was suggested. The performance enhancement of LHTES through fins configuration were quantitatively described based on complete melting time and heat storage capacity, and the conclusions are arrived as follows: when 〈em〉N〈/em〉 ≤ 6, the optimum arrangement is the lower fins, while it is the angled fins when 〈em〉N〈/em〉 〉 6. For 〈em〉N〈/em〉 = 6, only 〈em〉l〈/em〉 could change the optimum arrangement of fins. At 〈em〉l〈/em〉 equals 0.5 and 0.95, the optimum arrangement is angled case. While at 〈em〉l〈/em〉 = 0.75, the optimum arrangement is lower case. It is also found that the heat storage capacity of lower fins configuration is minimal compared to other three configurations.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Water Research, Volume 149〈/p〉 〈p〉Author(s): M. Aybar, P. Perez-Calleja, M. Li, J.P. Pavissich, R. Nerenberg〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The membrane-aerated biofilm reactor (MABR) is a novel wastewater treatment technology based on oxygen-supplying membranes. The counter diffusion of oxygen and electron donors in MABRs leads to unique behavior, and we hypothesized it also could impact predation. We used optical coherence tomography (OCT), microsensor analyses, and mathematical modeling to investigate predation in membrane-aerated biofilms (MABs). When protozoa were excluded from the inoculum, the MAB's OCT-observable void fraction was around 5%. When protozoa were included, the void fraction grew to nearly 50%, with large, continuous voids at the base of the biofilm. Real-time OCT imaging showed highly motile protozoa in the voids. MABs with protozoa and a high bulk COD (270 mg/L) only had 4% void fraction. DNA sequencing revealed a high relative abundance of amoeba in both high and low-COD MABs. Flagellates were only abundant in the low-COD MAB. Modeling also suggested a relationship between substrate concentrations, diffusion mode (co- or counter-diffusion), and biofilm void fraction. Results suggest that amoeba proliferate in the biofilm interior, especially in the aerobic zones. Voids form once COD limitation at the base of MABs allows predation rates to exceed microbial growth rates. Once formed, the voids provide a niche for motile protozoa, which expand the voids into a large, continuous gap. This increases the potential for biofilm sloughing, and may have detrimental effects on slow-growing, aerobic microorganisms such as nitrifying bacteria.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0043135418309011-fx1.jpg" width="453" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Water Research, Volume 149〈/p〉 〈p〉Author(s): C. Caicedo, K.-H. Rosenwinkel, M. Exner, W. Verstraete, R. Suchenwirth, P. Hartemann, R. Nogueira〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Wastewater treatment plants (WWTPs) have been identified as confirmed but until today underestimated sources of 〈em〉Legionella,〈/em〉 playing an important role in local and community cases and outbreaks of Legionnaires’ disease. In general, aerobic biological systems provide an optimum environment for the growth of 〈em〉Legionella〈/em〉 due to high organic nitrogen and oxygen concentrations, ideal temperatures and the presence of protozoa. However, few studies have investigated the occurrence of 〈em〉Legionella〈/em〉 in WWTPs, and many questions in regards to the interacting factors that promote the proliferation and persistence of 〈em〉Legionella〈/em〉 in these treatment systems are still unanswered. This critical review summarizes the current knowledge about 〈em〉Legionella〈/em〉 in municipal and industrial WWTPs, the conditions that might support their growth, as well as control strategies that have been applied. Furthermore, an overview of current quantification methods, guidelines and health risks associated with 〈em〉Legionella〈/em〉 in reclaimed wastewater is also discussed in depth. A better understanding of the conditions promoting the occurrence of 〈em〉Legionella〈/em〉 in WWTPs will contribute to the development of improved wastewater treatment technologies and/or innovative mitigation approaches to minimize future 〈em〉Legionella〈/em〉 outbreaks.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0043135418308972-fx1.jpg" width="284" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Solid State Sciences, Volume 85〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Solid State Sciences, Volume 85〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Solid State Sciences, Volume 85〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Soil Biology and Biochemistry, Volume 128〈/p〉 〈p〉Author(s): J.M. Kranabetter〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Forest floor carbon (C) sequestration has been negatively correlated with manganese (Mn) availability, possibly due to reduced efficacy of Mn-peridoxase enzymes produced by Agaricomycete fungi. I examined a soil C and Mn dataset from a podzolization gradient, along with fungal sporocarp Mn concentrations, to potentially corroborate this finding. An inverse power relationship between soil C and soil Mn content across temperate rainforests was confirmed, which provides further evidence of a Mn bottleneck in C turnover. Average Mn concentrations of saprotrophic sporocarps were greater than those of ectomycorrhizal fungi, and displayed a similar inverse correlation with increasing soil C. The absence or limited effectiveness of select saprotrophic fungi across Mn-depleted forest soils may be one mechanism behind impeded turnover of recalcitrant organic matter.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Soil Biology and Biochemistry, Volume 128〈/p〉 〈p〉Author(s): Charles R. Warren〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Phospholipids are isolated from crude lipid extracts by silica solid phase extraction (SPE), but for soils we don't know if phospholipids are the only fatty acid-based lipids present in the polar lipid fraction. Lipids extracted from three soils were fractionated with a silica SPE protocol commonly used for soils, with “neutrals” eluted by chloroform, “glycolipids” eluted by acetone, and “phospholipids” eluted by methanol. Fatty acid-based lipids were identified and quantified by liquid chromatography-mass spectrometry. Phospholipids were recovered in the methanol fraction, but this fraction also included betaine lipids. In two soils the methanol fraction was 3–6% betaine lipid while in one soil betaine lipids accounted for 48% of lipids in the methanol fraction. Clearly the fraction obtained by eluting lipids from silica with methanol is not purely phospholipid but can contain significant amounts of other polar lipids.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February–March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of the European Ceramic Society, Volume 39, Issues 2–3〈/p〉 〈p〉Author(s): Mattia Biesuz, Vincenzo M. Sglavo〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Flash sintering is a novel densification technology for ceramics, which allows a dramatic reduction of processing time and temperature. It represents a promising sintering route to reduce economic, energetic and environmental costs associated to firing. Moreover, it allows to develop peculiar and out-of-equilibrium microstructures.〈/p〉 〈p〉The flash process is complex and unusual, including different simultaneous physical and chemical phenomena and their understanding, explanation and implementation require an interdisciplinary approach from physics, to chemistry and engineering. In spite of the intensive work of several researchers, there is still a wide debate as for the predominant mechanisms responsible for flash sintering process.〈/p〉 〈p〉In the present review, the most significant and appealing mechanisms proposed for explaining the “flash” event are analyzed and discussed, with the aim to point out the level of knowledge reached so far and identify, at least, possible shared theories useful to propose future scientific activities and potential technological implementations.〈/p〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volumes 467–468〈/p〉 〈p〉Author(s): Xu Wu, Yalin Feng, Yali Du, Xuezhen Liu, Chunlei Zou, Zhe Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉LDHs templates (marked as CoAl-MnO〈sub〉2〈/sub〉-LDH and CoMnAl-CO〈sub〉3〈/sub〉-LDH) were fabricated via ion-exchange/redox reaction and hexamethylenetetramine (HMT) hydrolysis methods respectively. CoMnAl mixed metal oxides (marked as MnO〈sub〉2〈/sub〉/CoAl-LDO and CoMnAl-LDO) from the as-prepared LDHs templates were novelly prepared and tested as low-temperature NH〈sub〉3〈/sub〉-SCR catalysts. Catalytic evaluation pronouncedly affirmed that the catalytic performances of the as-acquired catalysts were vulnerable to the preparation method of precursor template, where MnO〈sub〉2〈/sub〉/CoAl-LDO presented preferable DeNOx activity (over 90% NOx conversion), N〈sub〉2〈/sub〉 selectivity and SO〈sub〉2〈/sub〉 resistance in much broader working temperature window (90–300 °C) than CoMnAl-LDO. Multiple characterizations revealed that the excellent catalytic performance of the MnO〈sub〉2〈/sub〉/CoAl-LDO could be attributed to its higher specific surface area which could promote dispersion of abundant Mn〈sup〉4+〈/sup〉 and Co〈sup〉3+〈/sup〉 species, and resultantly afforded stronger redox ability and more acid sites. Moreover, dynamic calculation confirmed that the relatively lower activation energy on MnO〈sub〉2〈/sub〉/CoAl-LDO for low-temperature NH〈sub〉3〈/sub〉-SCR reaction should be closely related to the occurrence of a more rapid redox cycle and in agreement with the excellent DeNOx performance.〈/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-S0169433218329702-ga1.jpg" width="413" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volumes 467–468〈/p〉 〈p〉Author(s): Sandra Jendrzej, Leonard Gondecki, Jörg Debus, Henning Moldenhauer, Peter Tenberge, Stephan Barcikowski, Bilal Gökce〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The lubricant is a central element in the transmission design. It primarily separates the two contact partners through a pressure-induced solidification in the lubrication gap, thus enabling the operation of heavily loaded sliding-rolling contacts. On the one hand, the quality and properties of a lubricant depend on the base oils, which differ by their viscosity and process-technological parameters. The addition of particulate additives gives the lubricants further functional properties that are not contained in the base oil. In this study, the influence of laser-synthesized yttria-stabilized zirconia nano- or submicrometer spheres as dispersed functional elements in the lubricant is studied, and their impact on wear and fatigue on the tooth flank is investigated. The work includes systematic investigations on the influence of the particle’s shape and size by running tests on a FZG gear test rig. Finally, the potential of the laser-generated particles as a lubricant additive is evaluated in a first conclusion.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Nuclear Materials, Volume 513〈/p〉 〈p〉Author(s): Matic Pečovnik, Sabina Markelj, Anže Založnik, Thomas Schwarz-Selinger〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The influence of grain size on deuterium transport and retention in tungsten was studied. For this purpose an experiment was carried out on three polycrystalline tungsten samples with different grain sizes and a single crystal sample with surface orientation 〈100〉. In order to increase deuterium retention and hence the sensitivity for detection, samples were first damaged by high energy W ions. After damaging, the samples were exposed to a flux of deuterium atoms at 600 K for 70 h. During the exposure the depth profile of the retained deuterium was measured by Nuclear Reaction Analysis using a 〈sup〉3〈/sup〉He ion beam. After the exposure the samples were also analysed by Thermal Desorption Spectroscopy. A clear difference in the time dependence of deuterium uptake was noticed between different samples. The experimental results were modeled using a rate-equation model. The influence of different grain size was modeled by changing the effective height of the potential barrier for deuterium atoms to enter into the bulk. We managed to successfully describe the transport of deuterium into the bulk of tungsten by reducing the potential barrier for samples with smaller grain sizes while the barrier for the sample with larger grain size was close to the value for the damaged single crystal sample.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0022311518307256-fx1.jpg" width="256" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 29 November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Tetrahedron, Volume 74, Issue 48〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Nuclear Materials, Volume 513〈/p〉 〈p〉Author(s): P.A. Burr, E. Kardoulaki, R. Holmes, S.C. Middleburgh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The stability, diffusivity and clustering behaviour of defects in uranium diboride (UB〈sub〉2〈/sub〉) was investigated in light of the potential application as a burnable absorber in nuclear fuel. UB〈sub〉2〈/sub〉 was found to accommodate limited deviations from stoichiometry, which should be a consideration when manufacturing and operating the material. Self-diffusivity of both U and B was found to be sluggish (10〈sup〉−14〈/sup〉 cm〈sup〉2〈/sup〉/s for B and 10〈sup〉−19〈/sup〉 cm〈sup〉2〈/sup〉/s for U at 2000K) and highly anisotropic, with migration along the basal planes being orders of magnitude faster than 〈em〉c〈/em〉-axis migration. The anisotropy of defect migration (both interstitials and vacancies) is predicted to hinder recombination of defects produced by collision cascades, thus limiting the radiation tolerance of the material. Boron and uranium vacancies exhibit a drive to cluster. Boron vacancies in particular, which are mobile on basal planes, are predicted to cluster into strongly bound di-vacancy, which in turn are less mobile. These are then predicted to grow into larger two-dimensional vacancy clusters on the B plane, leading to anisotropic swelling. We provide an analytical expression to predict the stability of these clusters based on purely geometrical considerations. Finally, the accommodation of Li, He and Xe onto vacancy clusters was considered. Li appears to stabilise the structure upon U depletion, while the retention of He and Xe appears to rise with increasing B depletion, through the formation of vacancy clusters.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Physica B: Condensed Matter, Volume 554〈/p〉 〈p〉Author(s): D. Bessas, I. Kantor, D. Bourazani, K. Georgalas, N. Biniskos, L. Zhang, A.I. Dugulan, E. Syskakis〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Bulk Sr〈sub〉2〈/sub〉PdO〈sub〉3〈/sub〉 was synthesized by a modified solid state reaction and a detailed characterization was carried out using both microscopic and macroscopic experimental techniques. Pd site exhibits an electric field gradient of 5.9(1) ⋅ 10〈sup〉17〈/sup〉 V/cm〈sup〉2〈/sup〉 due to the anisotropic local atomic configuration. A Curie - paramagnetic susceptibility indicating antiferromagnetic interactions superimposed to a core diamagnetic state is confirmed. A linear volume thermal expansion with a coefficient of 3.0(1) ⋅ 10〈sup〉−5〈/sup〉 K〈sup〉−1〈/sup〉 at room temperature is extracted. A collection of Einstein oscillators, with an Einstein temperature of about 115 K, is involved in the thermal transport. Large atomic displacements were observed in Sr vibrations. No Pd or Sr valence change is observed up to 900 K. A moderate anharmonicity is identified and quantified in a macroscopic Grüneisen parameter of 2.5(1) at room temperature. The electrical resistivity reveals a semiconducting behaviour. A systematic reduction in electrical resistivity and a change in the conduction mechanism is observed upon thermal cycling which indicates that a peculiar electronic mechanism is involved.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Phytochemistry, Volume 157〈/p〉 〈p〉Author(s): XingRong Peng, Lei Li, JinRun Dong, ShuangYang Lu, Jing Lu, XiaoNian Li, Lin Zhou, MingHua Qiu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Twelve previously undescribed lanostane-type triterpenoids, including three triterpenoids with a 〈em〉γ〈/em〉-lactone ring, namely applanlactones A‒C, four highly oxygenated lanostane triterpenoids, namely methyl applaniate A and applanoic acids B‒D, as well as five C21 nortriterpenoids, applanones A‒E were isolated from the fruiting bodies of 〈em〉Ganoderma applanatum〈/em〉 (Pers.) Pat.〈em〉.〈/em〉 Their structures were elucidated by 1D, 2D NMR and MS spectra, as well as X-ray crystallographic analyses. Meanwhile, applanlactone A, methyl applaniate A and applanoic acid B showed inhibitory effects for the proliferation of hepatic stellate cells (HSCs) induced by transforming growth factor-〈em〉β〈/em〉1 (TGF-〈em〉β〈/em〉1) 〈em〉in vitro〈/em〉.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Three polyoxygenated lanostane triterpenoids isolated from the fruiting bodies of 〈em〉Ganoderma applanatum〈/em〉 showed anti-liver fibrosis activities.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0031942218303352-fx1.jpg" width="369" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Energy Procedia, Volume 151〈/p〉 〈p〉Author(s): Muhammad Sheikh, Sheikh Rehman, Mustafa Elkady〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Lithium-ion batteries are considered efficient energy source for current electric vehicles (EVs) due to better power and energy densities; however, safety of these batteries is vital when it comes to large scale deployment. Short circuit of batteries is one of the concern as it can spread quickly within battery module or pack if not controlled at cell level. In this paper single lithium-ion battery cell is investigated where two mechanical abuse conditions, compression and bending are used to investigate short circuit and propagation of failures due to short circuit. Quasi-static loading approach is used for mechanical abuse conditions. Numerical simulation tool LS-DYNA is used to model battery cell where each layer thickness is considered 0.3mm and concentric layered formation is used for this purpose. Separator failures are analysed using simulation models, where at maximum displacement separator temperature increases significantly and drop in force is observed, another significant finding from separator layer analysis is the high-temperature locations. In the case of three-point bend test which has immediate short circuit response and circular punch test where a slow build-up of short circuit is evident from experiment, separator failure occurs well in advance for short circuit.〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Energy Procedia, Volume 151〈/p〉 〈p〉Author(s): Abid Soomro, Mustafa E. Amiryar, Keith R. Pullen, Daniel Nankoo〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉For stable operation of the electrical grid, it is vital to maintain a balance between demand and supply of electrical power. Imbalance at any instant between consumption and generation causes voltage and frequency instability. Intermittent generation (wind and solar) in power systems is more likely to cause such imbalances hence the existence of frequency and voltage variations. To address stability issues due to integration of intermittent renewable sources into the grid, a storage device is required which can quickly respond to the power fluctuations. A Flywheel Energy Storage System (FESS) has the capability to respond within a sub-second timescale and is able to address the problems caused by power variations. The performance of FESS is highly dependent on the type of motor/generator (MG) set which is the key component generating or absorbing power from grid. The three main types of electrical machines used in FESS applications are synchronous machine (SM), induction machine (IM) and the switched reluctance machine (SRM). SRM is less commonly used due to high current ripples and complex torque control [1]. SM is used for high speed applications due to its high efficiency and IM is used for high power applications due to its rough construction. This research focuses on the comparison of synchronous and induction machines used in flywheel energy storage systems for microgrid applications [2]. The operation and controlling schemes of each electrical machine has been described as used in the analysis made in the MATLAB/Simulink environment.〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Energy Procedia, Volume 151〈/p〉 〈p〉Author(s): Luke Price〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉It has been shown from the late 70s onwards that photo-catalytic CO〈sub〉2〈/sub〉 reduction can be achieved using complex catalysts. Theoretically reduction can occur at different potentials yielding various organic molecules. Using these catalysts allows the reaction to go 〈em〉via〈/em〉 a multiple proton/electron route. Successful upscale of a working system would mean a route to usable chemicals along with a reduction in atmospheric CO〈sub〉2〈/sub〉 levels. The downside to the complexes used is their rather low efficiencies. More control over the catalysis is desired, along with easier ways to remove the catalysts from the end product. Attachment onto surfaces would achieve this through more control over catalytic orientation allowing the tailoring of properties through surface modifications. Semiconducting surfaces are of great importance in this area as the attachment of a complex catalyst onto the surface not only gives the possibility of altering catalyst efficiency but can also be used as a conduction band bridge between photosensitizing molecule and attached catalyst as a result of different energy states.〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Energy Procedia, Volume 151〈/p〉 〈p〉Author(s): Daniel R. Wright, Nuria Garcia-Araez, John R. Owen〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Lithium-ion batteries have revolutionised the energy storage market; applications for batteries are rapidly expanding with demands for high performance batteries required in many technological fields. In applications such as portable devices or electric vehicles, lithium-ion batteries have currently no contender in terms of energy density or durability. However, the restricted temperature range of -25 °C to 60 °C is a problem for a number of applications that require high energy rechargeable batteries that operate at a high temperature (〉100 °C). This review discusses the work that has been done on the side of electrodes and electrolytes for use in high temperature Li-ion batteries.〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Energy Procedia, Volume 151〈/p〉 〈p〉Author(s): James K.W. Moore, Denis Cumming, Solomon Brown〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉The United Kingdom has a target of reducing fossil fuel emissions to 80% of 1990s emissions levels by 2050 and the National Grid is highly likely to see a vast portion of displaced currently fossil fuelled heating provision. There is therefore a significant need for research into alternatives to grid re-enforcement and additional power stations. Thermal energy storage systems present one such alternative via the decoupling of energy production and consumption in both industrial and domestic heating demand. Reversible phase change in materials such as paraffin waxes, inorganic salts and metal alloys represent such a technology. For these, the ability to empirically assess a given phase change is invaluable for determining materials of interest, system characteristics and optimisation of systems design in addition to quantitatively validate any given numerical system models.〈/p〉 〈p〉In this work the development and evolution of the solid to liquid phase transition in two organic phase change materials: beeswax and paraffin wax is investigated. These are characterised via visible and thermal photography of an ongoing melt/solidification in a 5cm dimensioned cube constructed of several differing wall materials. Isothermal heat is supplied via the bottom surface by a laboratory hot plate.〈/p〉 〈p〉During the melting and re-solidification process, the thermal conduction through non-infra-red transparent wall materials has been unable to indicate the solid-liquid interface or melt/solidification times. Direct infra-red transmission through the infra-red transparent materials and visible light analysis through the transparent walls has been able to provide a solid-liquid interface track and melting time to completion but is unable to confer any useful information during the solidification process due to premature solidification on the wall exposed to imaging.〈/p〉 〈/div〉

Description: 〈p〉Publication date: 15 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Scripta Materialia, Volume 162〈/p〉 〈p〉Author(s): Mageshwari Komarasamy, Tianhao Wang, Kaimiao Liu, Luis Reza-Nieto, Rajiv S. Mishra〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Modification of a coarse B2 phase and realization of hierarchical multi-phase microstructures were achieved in an Al〈sub〉0.5〈/sub〉CrFeCoNi complex concentrated alloy (CCA) using high-temperature severe plastic deformation (HTSPD). Under HTSPD conditions, a thermodynamically stable B2 phase dissolved, while a thermodynamically unstable coarse Al〈sub〉3〈/sub〉Ni phase formed. Al supersaturation in the matrix after HTSPD led to the formation of fine B2 precipitates during the subsequent aging treatment. The combination of Al〈sub〉3〈/sub〉Ni for enhanced work hardening and fine B2 precipitates for strength resulted in excellent strength-ductility of 1400 MPa and 20%.〈/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-S1359646218306523-ga1.jpg" width="415" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Catalysis, Volume 368〈/p〉 〈p〉Author(s): Michiel Janssen, Lisa Van Emelen, Carlos Marquez, Trees De Baerdemaeker, Dirk E. De Vos〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Selective functionalization of hydrocarbons remains one of the most challenging reactions in organic chemistry. With respect to terminal C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉H hydroxylation, electrophilic activation by late transition metals has been considered a promising route. We report the use of Shilov-chemistry inspired Pt catalysis in acetic acid as suitable solvent for the formation of primary alcohols from long linear alkanes. By reacting 〈em〉n〈/em〉-heptane with K〈sub〉2〈/sub〉PtCl〈sub〉4〈/sub〉 under an oxygen atmosphere, a positional selectivity of 18% was reached for 1-heptanol among the C〈sub〉7〈/sub〉 alcohols at significantly high conversion (37%). Moreover, we provide evidence for the intrinsic activity of Pt(II), along with elucidation of the role of specific additives as coordinating ligands. Both acetic anhydride (AA), initially added as protecting agent, and sulfuric acid proved to be essential to obtain an active alkane hydroxylation system; via ESI-MS [Pt(AA)(OSO〈sub〉3〈/sub〉H)〈sub〉3〈/sub〉(H〈sub〉2〈/sub〉O)]〈sup〉+〈/sup〉 and [Pt(CH〈sub〉3〈/sub〉COOH)(OSO〈sub〉3〈/sub〉H)〈sub〉3〈/sub〉(H〈sub〉2〈/sub〉O)]〈sup〉+〈/sup〉 were identified in the active catalytic system. Furthermore, nonselective overoxidation originates from various side reactions, for which a reaction network is proposed. Finally, the stability of the 〈em〉in situ〈/em〉 formed esters was studied in detail by recording time-dependent profiles for the decomposition of different positional isomers of 〈em〉n〈/em〉-octyl acetate, as well as of its fluorinated analogues. Altogether, these results illustrate the clear potential of the proposed concept in forming primary alcohols directly from cheap and abundant alkanes.〈/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-S0021951718304044-ga1.jpg" width="369" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 1 November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment〈/p〉 〈p〉Author(s): S. Monzani, A. Andreazza, M. Citterio, P. Fontana, M. Ianna, T. Lari, V. Liberali, F. Ragusa, C. Sbarra, A. Sidoti, A. Stabile〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Monochromatic X and gamma rays are a standard calibration tool for semiconductor detector. For finely segmented pixel detectors, like the ones foreseen for HL-LHC detector upgrades, the single pixel spectrum is affected by charge sharing across nearby pixels, due to diffusion and the finite range of photoelectrons, resulting in a low energy continuum below the photoelectric peak. In this paper a systematic simulation study will be presented. The shape of the transition between the photoelectric peak and the continuum is determined by diffusion and needs to be unfolded for a correct estimation of the energy resolution. Simulation results are compared with data collected with different high-resistivity CMOS devices with 50 × 250 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll" altimg="si1.gif"〉〈mi mathvariant="normal"〉μ〈/mi〉〈/math〉m〈sup〉2〈/sup〉 pixel size and photon energies between 13 and 60 keV. They show a good agreement, highlighting the potential usage of the whole single pixel spectrum to derive device characteristics.〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Catalysis, Volume 368〈/p〉 〈p〉Author(s): Andrea Jouve, Gergely Nagy, Ferenc Somodi, Cristina Tiozzo, Alberto Villa, Antonella Balerna, Andrea Beck, Claudio Evangelisti, Laura Prati〈/p〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0021951718304032-ga1.jpg" width="379" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Catalysis, Volume 368〈/p〉 〈p〉Author(s): Gennady I. Panov, Mikhail V. Parfenov, Eugeny V. Starokon, Alexandr S. Kharitonov〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Investigation of reaction mechanisms by identifying the intermediates released into the gas phase is most effective at low conversion of reactants, ideally approaching zero. However, conversions below 0.5–1% are rarely used, due to the difficulty of analysis of low-concentration products. The mechanism of the title reaction is a subject of long-term discussion. We studied the mechanism using an original ultralow conversion (ULC) method. The idea is to perform the analysis of products after their preliminary accumulation in a suitable absorbent at the reactor outlet. This allows decreasing conversion by 2–3 orders of magnitude. The ULC experiments were conducted with a Bi–Mo catalyst at 100–250 °C and with propene conversion down to 0.001%. A new so-called allyl hydroxylation mechanism was revealed. A key step is the hydroxylation of the CH〈sub〉3〈/sub〉 group to form an allyl alcohol intermediate, which is further oxidized to acrolein. The mechanism explains all reaction features and was confirmed by experiments at 350 °C.〈/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-S0021951718303804-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Chromatography B, Volume 1105〈/p〉 〈p〉Author(s): Jesper Sundell, Emile Bienvenu, Sofia Birgersson, Angela Äbelö, Michael Ashton, Kurt-Jürgen Hoffmann〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Co-infection of tuberculosis in HIV-patients is a major health concern worldwide and especially so in Sub-Saharan Africa. To enhance the study of potential drug-drug interactions when simultaneously treating the two infections, a liquid chromatography tandem mass spectrometry method was developed for the quantitation of the four first line anti-tuberculosis drugs isoniazid, rifampicin, pyrazinamide, ethambutol and four of their major metabolites in human plasma.〈/p〉 〈p〉Analytes were extracted from 200 μL of plasma using a sequential liquid-liquid extraction with ethyl acetate at neutral and acidic pH. The combined extracts were analyzed by liquid chromatography with mass spectrometric detection in a multiple reaction monitoring mode. The chromatographic separation was performed on a hydrophilic interaction column using a stepwise gradient with two mobile phases consisting of water with 0.3% formic acid and methanol with 0.3% formic acid, respectively. The total run time of each analysis was 4 min. The lower limit of quantification applied was 40 ng/mL for ethambutol, acetylisoniazid and 25-desacetylrifampicin, 60 ng/mL for 5-hydroxypyrazinamide, 80 ng/mL for isoniazid and isonicotinic acid, 200 ng/mL for rifampicin and 320 ng/mL for pyrazinamide. The method was validated according to US Food and Drug Administration guidance. The method exhibited adequate accuracy (87.1–114.9%), precision (CV 〈 12.8%) and specificity. Recovery and matrix effect were consistent (CV 〈 11.9%). The extracted samples were stable in the autosampler at 8 °C for up to 24 h as well as after three freeze-thaw cycles (recovery 〉 86.3%). The method has been shown to be robust for the analysis of the stated drugs and metabolites in human plasma obtained from 73 patients receiving these four first line anti-tuberculosis drugs.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 6 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 International Journal of Hydrogen Energy, Volume 43, Issue 49〈/p〉 〈p〉Author(s): Ho Seong Lee, Hyun Mi Lee, Jun-Young Park, Hyung-Tae Lim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study investigated the effect of H〈sub〉2〈/sub〉S concentration (5, 10 and 50 ppm) on the degradation and performance of Ni-YSZ anode supported solid oxide fuel cells. When supplied with hydrogen fuel containing H〈sub〉2〈/sub〉S, the cell voltage dropped rapidly, and with increasing H〈sub〉2〈/sub〉S concentration, voltage drop % increased (due to higher sulfur coverage on the Ni surface) and saturated more rapidly. A high concentration (50 ppm) of H〈sub〉2〈/sub〉S led to an additional, slow rate voltage loss. In all cases, cell performance did not completely recover even after being supplied with H〈sub〉2〈/sub〉S-free hydrogen fuel, because of the incomplete desorption of sulfur from the Ni surface. After the performance tests, nickel sulfides were detected on the Ni surface by Raman spectra, which were produced by the reaction of the remaining adsorbed sulfur with Ni during the cooling process. This indicates that the formation of nickel sulfides was not responsible for the secondary voltage drop. SEM/EDS analyses combined with FIB revealed that the reason for the additional 2〈sup〉nd〈/sup〉 drop was Ni oxidation; at a high sulfur coverage ratio (50 ppm), the outer layer of the Ni particle was oxidized by oxygen ions transported from the electrolyte. This indicates that H〈sub〉2〈/sub〉S concentration as well as current density is a critical factor for Ni oxidation, and gives rise to the second voltage drop (irreversible cell degradation). The present work showed that the degradation behavior and phenomenon can differ significantly depending on the concentration of H〈sub〉2〈/sub〉S, i.e., permanent changes may or may not occur on the anode (such as Ni oxidation) depending upon H〈sub〉2〈/sub〉S concentration.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 6 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 International Journal of Hydrogen Energy, Volume 43, Issue 49〈/p〉 〈p〉Author(s): Tami Astie Ulhiza, Noor Illi Mohamad Puad, Azlin Suhaida Azmi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Sago wastewater (SWW) causes pollution to the environment due to its high organic content. Annually, about 2.5 million tons of SWW is produced in Malaysia. In this study, the potential of SWW as a substrate for biohydrogen production by 〈em〉Enterobacter aerogenes (E. aerogenes)〈/em〉 was evaluated. Response Surface Methodology (RSM) was employed to find the optimum conditions. From preliminary optimization, it was found that the most significant factors were yeast extract, temperature, and inoculum size. According to Face Centered Central Composite Design (FCCCD), the maximum hydrogen concentration and yield were 630.67 μmol/L and 7.42 mmol H〈sub〉2〈/sub〉/mol glucose, respectively, which is obtained from the sample supplemented with 4.8 g/L yeast extract concentration, 5% inoculum, and incubated at the temperature of 31 °C. Cumulative hydrogen production curve fitted by the modified Gompertz equation suggested that 〈em〉H〈/em〉〈sub〉〈em〉max〈/em〉〈/sub〉, 〈em〉R〈/em〉〈sub〉〈em〉max〈/em〉〈/sub〉, and 〈em〉λ〈/em〉 from this study were 15.10 mL, 2.18 mL/h, and 9.84 h, respectively.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 501〈/p〉 〈p〉Author(s): G. Gorni, M.J. Pascual, A. Caballero, J.J. Velázquez, J. Mosa, Y. Castro, A. Durán〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The crystallization mechanism of LaF〈sub〉3〈/sub〉 in sol-gel oxyfluoride glass-ceramics in the system SiO〈sub〉2〈/sub〉-LaF〈sub〉3〈/sub〉 has been studied using DTA, XRD, FTIR, HRTEM and NMR. Based on classical calculations of non-isothermal DTA curves involving Ozawas's plots, a diffusion-controlled process should be responsible for the fluorides crystallization similarly to that obtained for melt-quenching oxyfluoride glass-ceramics. Therefore, an increase of the crystal size and fraction is expected when increasing the time and/or temperature of the treatment. Nevertheless, XRD, FIR, HRTEM and NMR demonstrated that neither bigger crystals nor higher crystal fraction are obtained for treatment times longer than 1 min at 550 °C. However, further heat treatment causes that the structural order of the crystals is lost. On the other hand, typical fluorides crystallization temperatures (~300 °C) in sol-gel materials are much lower than T〈sub〉g〈/sub〉 of the matrix (~1130 °C) thus being very different to what observed for oxyfluoride glasses prepared by melt-quenching. The proposed crystallization mechanism is a fast process that occurs when crystallization temperature is reached. This behavior is explained as a chemical reaction from the xerogels, followed by the fast precipitation of the nanocrystals without energy barrier. The nanocrystals are unstable in the surrounding SiO〈sub〉2〈/sub〉 matrix for aging at crystallization or higher temperatures. These treatments lead to a dissolution process, favored by the compositional gradient between matrix and crystals, which drive the material to reach the equilibrium.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 501〈/p〉 〈p〉Author(s): Jürn W.P. Schmelzer, Alexander S. Abyzov, Vladimir M. Fokin, Christoph Schick〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉General relations for the dependence of the thermodynamic driving force of crystallization and the specific interfacial energy melt-crystal of critical crystal clusters on temperature and pressure are derived. Its application to the analysis of experimental data on crystal nucleation seems to support at a first glance a proposal by Kauzmann on the existence of a pseudo-spinodal curve in melt-crystallization. Provided this assumption is true, Kauzmann temperature (and for pressure-induced nucleation, the Kauzmann pressure) cannot be reached by a metastable liquid due to intensive crystallization processes occurring in its vicinity. However, such suggestion cannot be retained taking into account the kinetic terms (diffusion coefficients, viscosity) in the expression for the nucleation rate. The absence of a pseudo-spinodal in melt-crystallization can be verified also in an alternative way by considering the characteristic time scales of crystallization and relaxation. Finally, it is shown that the phenomenon denoted commonly as Kauzmann paradox is merely an untypical as compared to normal conditions type of behavior. Neither in its original formulation nor in its consequences it results in any contradictions with basic laws of nature. They are prevented either by normal (not associated with a pseudo-spinodal) crystallization or a conventional glass transition.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 501〈/p〉 〈p〉Author(s): J. Gilabert, M.P. Gómez-Tena, V. Sanz, S. Mestre〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉The effect of a post-synthesis thermal treatment on CoCr〈sub〉2−2Ψ〈/sub〉Al〈sub〉2Ψ〈/sub〉O〈sub〉4〈/sub〉 (0.0 ≤ Ψ ≤ 1.0) ceramic pigments synthesized by Solution Combustion Synthesis (SCS) has been studied. As-synthesized SCS pigments were treated at two different calcination temperatures (800 °C and 1000 °C) to study changes in mineralogy, microstructure and thermal behaviour, as well as their effect over the colouring power.〈/p〉 〈p〉Spinel-type 〈em〉Fd〈/em〉-3〈em〉m〈/em〉 crystalline structure was developed in all cases. Nevertheless, crystallinity parameters were highly affected by both analysed processing parameters: composition (Ψ) and post-synthesis calcination temperature (T〈sub〉c〈/sub〉). A Cr(III) enrichment along with T〈sub〉c〈/sub〉 increase favoured ion rearrangement to promote sample crystallization and crystallite growth. Fast kinetics of SCS makes Al-rich spinels with transition metals difficult to be synthesized. The application of a secondary thermal treatment resulted in a favourable evolution towards a well-crystallized structure. Lattice parameter did not seem to be affected by T〈sub〉c〈/sub〉, although it evolved indeed with composition. From a microstructural point of view, as-synthesized pigments were foamy, with a very low bulk density and nanometric grain size. After the thermal treatment, larger grain sizes were obtained, especially for the samples richer in Al and treated at higher T〈sub〉c〈/sub〉.〈/p〉 〈p〉All pigments developed intense colours in a transparent glaze without showing heterogeneities, indicating a stable behaviour against glazing process. Glaze colour evolved from green to perfectly blue shades, indicating an important dependence on composition. Nevertheless, colouring power seemed to be rather affected by calcination process.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Radiation Measurements, Volume 119〈/p〉 〈p〉Author(s): Alessio Parisi, Luana de Freitas Nascimento, Olivier Van Hoey, Patrice Mégret, Hisashi Kitamura, Satoshi Kodaira, Filip Vanhavere〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Lithium fluoride thermoluminescent radiation detectors with different dopant concentrations (〈sup〉7〈/sup〉LiF:Mg,Ti and 〈sup〉7〈/sup〉LiF:Mg,Cu,P) were exposed to 〈sup〉1〈/sup〉H and 〈sup〉4〈/sup〉He ions at the Heavy Ion Medical Accelerator in Chiba (HIMAC) in order to investigate their response to energetic light charged particles. Computer simulations with the Monte Carlo code PHITS were performed for a better interpretation of the experimental data. The results were compared with literature efficiency data and with the results of a recently developed microdosimetric efficiency model. In case of the main peak signal of 〈sup〉7〈/sup〉LiF:Mg,Ti detectors, the determined efficiency values are in good agreement with previous investigations. Discrepancies in the efficiency of high temperature signal due to well-known non-linearity effects are reported. For 〈sup〉7〈/sup〉LiF:Mg,Cu,P detectors, an anomalous thermoluminescence behavior in the low temperature part of the signal was found and discussed. Depending on the light quantification process, differences up to 30% in the dose assessment can be obtained, affecting also the relative efficiency determination process. An explanation of this phenomenon as a consequence of local migration of the charged carriers between the low temperature peaks and the main peak is presented. The implications of these findings on the use of LiF:Mg,Cu,P detectors in radiation environments characterized by the presence of 〈sup〉1〈/sup〉H and 〈sup〉4〈/sup〉He ions (i.e. space and proton therapy) are discussed. In order to avoid the occurrence of this anomalous behavior, it is advised to pre-heat the detectors after energetic light particle exposures.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Ecological Engineering, Volume 125〈/p〉 〈p〉Author(s): Cristina Lazcano, Cameron Robinson, Golnoush Hassanpour, Maria Strack〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Northern peatlands store approximately one third of the global soil carbon (C) stocks. Peat extraction for horticulture changes C fluxes turning these soils from sinks into large sources of C emitted to the atmosphere as greenhouse gases. Restoring hydrological conditions may not be enough for returning the C sink function of these ecosystems and a recovery of the original Sphagnum-dominated vegetation cover could be necessary. Here we tested the effects of the moss layer-transfer technique (MLTT) on the CO〈sub〉2〈/sub〉 and CH〈sub〉4〈/sub〉 fluxes three years after restoration of a minerotrophic cutover peatland in Quebec, Canada. Gas emissions were compared to nearby undisturbed plots, and plots with restored hydrology but without vegetation transfer. The main drivers for the observed emissions were inferred from the relationships with relevant environmental variables (vegetation cover, water table depth and temperature). Restoration of the extracted minerotrophic fen through the MLTT produced significant changes in the exchange of CO〈sub〉2〈/sub〉, bringing these fluxes closer to undisturbed plots than plots with restored hydrology only, which remained C sources throughout the study. Methane emissions were generally low across all the restored plots and far from natural levels, with only a slight increase at the MLTT restored plots observed during the third year. Even though the MLTT failed to recover the original bryophyte-dominated vegetation, the observed changes in the emissions of CO〈sub〉2〈/sub〉 and CH〈sub〉4〈/sub〉 at the restored plots were strongly associated with changes in vegetation cover (i.e. increase in vascular plants), supporting the use of this restoration technique to recover the C sink function of harvested minerotrophic peatlands.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 31 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Power Sources, Volume 408〈/p〉 〈p〉Author(s): Guoping Chen, Xiong Song, Suqing Wang, Xinzhi Chen, Haihui Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Lithium-sulfur (Li〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉S) batteries are attractive candidates for advanced energy storage devices. However, the low utilization of sulfur and the severe “shuttle effect” hinder the commercialization of Li〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉S batteries. Herein, we design an ultra-thin and lightweight two-dimensional (2D) molybdenum nitride nanosheets layer to modify Celgard (denoted as MoN〈sub〉x〈/sub〉/Celgard) separator to promote the electrochemical performance of Li〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉S batteries. Benefiting from the 2D polar molybdenum nitride nanosheets, the obtained molybdenum nitride layer can effectively suppress the shuttle effect via the synergistic effect of structural confinement and chemical absorption. Meanwhile, molybdenum nitride nanosheets layer possesses metallic and catalytic characteristics, which are beneficial for high sulfur utilization. Therefore, the Li〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉S batteries using MoN〈sub〉x〈/sub〉/Celgard separator with multifunction exhibit high capacity and outstanding cycling performance. It delivers a high discharge capacity of 1298 mA h g〈sup〉−1〈/sup〉 at 0.1C and sustain a capacity of 566 mA h g〈sup〉−1〈/sup〉 after 500 cycles at 0.5C, corresponding with the capacity fading rate of only 0.063% per cycle.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 31 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Soil Dynamics and Earthquake Engineering〈/p〉 〈p〉Author(s): Vladimir A. Osinov, Stylianos Chrisopoulos, Theodoros Triantafyllidis〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The paper presents a numerical analysis of the dynamic deformation of the tunnel lining and the soil caused by a blast-induced pressure pulse of a moderate amplitude (several megapascals) inside the tunnel. The tunnel lining is circular and consists of individual concrete linearly elastic tubbings. The tunnel is located at a depth of 15 m in fully saturated granular soil. Effective-stress changes are described by a hypoplasticity model. The possibility of pore water cavitation at zero absolute pore pressure is taken into account. The problem is solved in a two-dimensional plane-strain formulation with the finite-element program Abaqus/Standard. Emphasis is placed on fine spatial discretization in order to obtain accurate solutions. Stresses and deformations in the lining and in the soil are analysed in detail. The solutions reveal an important role of the strong nonlinearity in the soil behaviour due to the pore water cavitation.〈/p〉〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 514〈/p〉 〈p〉Author(s): Mahasin Ali Khan, Meghma Bera, Robert A. Spicer, Teresa E.V. Spicer, Subir Bera〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Fossil leaf floras, from the latest Miocene-Pliocene Siwalik Group exposed in Bhutan, sub-Himalaya, are subjected to a CLAMP (Climate Leaf Analysis Multivariate Program) analysis using a high-resolution gridded climate calibration. The CLAMP analysis of 27 different morphotypes of fossil leaves indicates a mean annual temperature (MAT) of 24.1 °C ± 2.8 °C; a cold month mean temperature (CMMT) of 18.9 °C ± 4 °C and a warm month mean temperature (WMMT) of 27.8 °C ± 3.3 °C. The analysis also suggests a weak monsoonal climate (the monsoon index, MSI 46.7; present MSI 52) with growing season precipitation (GSP) of 1819 ± 916 mm (present GSP 2490 mm). Here we also compare palaeoclimate estimates of the latest Miocene-Pliocene Siwalik Group flora from Bhutan (c. 6 to 3.8 Ma) with those of previously investigated Siwalik Group floras from the Miocene-Pleistocene of Arunachal, India and Miocene Siwalik floras of Darjeeling, India which characterise the monsoon signature at the time of deposition. Since all the Siwalik floras of the eastern Himalaya (Darjeeling and Arunachal Pradesh) spanning the mid-Miocene to Pleistocene yield almost the same values we suggest that overall the eastern Himalayan Siwalik climate appears to have been remarkably uniform over the past 15 million years. The MAT result of the Bhutan Siwalik flora differs by just 0.6 °C from Arunachal and 1.2 °C from Darjeeling Siwalik floras. For all Siwalik fossil assemblages, WMMTs, CMMTs and LGSs (length of the growing season) are similar and consistent (WMMTs around 28 °C, CMMTs around 18 °C and LGSs around 12 months). Similarly, the mean annual relative humidity (RH) and specific humidity (SH) appear to have been uniformly around 80% and 14 g/kg respectively throughout the Neogene of the eastern Himalayan Siwaliks. Changes in the monsoon index suggest that in both Bhutan and Arunachal sub-Himalaya, there has been little change in the intensity of the monsoon since mid-Miocene time, while further west in the Darjeeling area precipitation seasonality has increased since the mid-Miocene.〈/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-S0031018218303523-ga1.jpg" width="327" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Remote Sensing of Environment, Volume 220〈/p〉 〈p〉Author(s): Xiyu Chen, Lin Liu, Annett Bartsch〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Microwave remote sensing, both active or passive, can provide useful information about the freeze/thaw (F/T) state of soil near the surface. Here we apply an edge detection algorithm on time series of indicators derived from measurements of SMAP L-band radiometer and ASCAT C-band scatterometer to detect the freeze/thaw onsets of surface soil. Comparing these results against the onsets derived from in situ measurements in Alaska, we demonstrate that this algorithm is an effective approach to detect onsets of the soil F/T transition. More specifically, our results show that the thawing onsets estimated from the SMAP data occurred 5 to 13 days earlier than the onsets estimated from the in situ measurements, which is likely due to the influence of snowmelt on the radiometer signal. The thawing onsets estimated from the ASCAT data were about 6 days later than the in situ onsets. Our estimated freezing onsets from each microwave remote sensing dataset were close to the in situ onsets (1–5 days). We also compare our estimated onsets with those from the SMAP Level 3 F/T product and the mean biases for thawing and freezing onsets are 1 ± 2 and 1 ± 3 days, respectively. Furthermore, we illustrate the complementary nature of the SMAP and ASCAT measurements and the potential for combining these two to differentiate snowmelt from soil thawing events.〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Remote Sensing of Environment, Volume 220〈/p〉 〈p〉Author(s): Mathilde Cancet, David Griffin, Madeleine Cahill, Bertrand Chapron, Johnny Johannessen, Craig Donlon〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Australia's marginal seas include a wide range of ocean current regimes ranging from tide-dominated in the North-West where the continental shelf is wide, to boundary current- and eddy-dominated in the South-East, where the shelf is narrow. Here, we take the opportunity to test the GlobCurrent surface ocean current products against in-situ observations in these two contrasting regimes. Observations by Acoustic Doppler Current Profiler (ADCP) instruments of Australia's Integrated Marine Observing System (IMOS) and drifting buoys of the Global Drifting Programme (GDP) are used.〈/p〉 〈p〉The monthly-timescale variability of the GlobCurrent alongshore current component is in moderately good agreement with the observations on the continental shelf in the South-East but neither the shorter period variability nor the long-term mean are representative of the ADCP observations. While the observed tidal currents are negligibly small, the wind-driven signals are not. But these are evidently too transient to be adequately sampled by altimetry. The inclusion of an Ekman component does not represent these signals because the interaction of the Ekman transport with the coastal boundary condition is not included. Similarly, the error of the time-mean velocity, which is the dominant error, is because that product is not designed to represent the highly anisotropic nature of the sea level gradients over the continental shelf nor the constraints on the flow field that are imposed by the topography. We thus conclude that the GlobCurrent product needs improvements before it can be described as very suitable for applications on this, and probably other, narrow continental shelf. Off the continental shelf, in contrast, the GlobCurrent products compare quite well with the trajectories of drifting buoys, confirming that the products are quite suitable for blue-water applications.〈/p〉 〈p〉In contrast to the South-East, the tides are very strong in the North-West region of Australia. The sub-tidal variability is weak, in both relative and absolute senses. Consequently, the removal of the tidal signal from the sea level observations needs to be very complete for the residual error to be smaller than the true sub-tidal signal. Transient wind forced signals are also occasionally large so this step of the de-aliasing also needs to be very accurate. Unfortunately, it appears that more work is required before accurate estimates of sub-tidal variability are available from GlobCurrent: the magnitude of the GlobCurrent estimates of sub-tidal current variability far exceed the magnitude of, and are uncorrelated with, the detided ADCP data.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Organic Geochemistry, Volume 125〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Precambrian Research, Volume 320〈/p〉 〈p〉Author(s): Hui C.G. Zhang, Jia-Hui Liu, Yi-Chao Chen, Qian W.L. Zhang, Van Tho Pham, Tao Peng, Zhen M.G. Li, Chun-Ming Wu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Mafic and felsic granulite from the Miyun metamorphic complex, northeast Beijing, North China Craton, occur as either interlayers or lenses within the Late Archean TTG gneiss. In the mafic granulite, the metamorphic peak assemblages (M1) are represented by porphyroblast minerals plus matrix minerals (orthopyroxene + clinopyroxene + plagioclase + quartz ± K-feldspar ± hornblende ± biotite) as well as accessory minerals of zircon + apatite + ilmenite ± magnetite, the post-peak assemblages (M2) are characterized by “red-eye socket” symplectites (garnet + clinopyroxene + plagioclase + quartz) rimming the orthopyroxene or clinopyroxene porphyroblast as well as accessory minerals of rutile, and the final retrograde assemblages (M3) are marked by the hornblende-biotite intergrowth. As for the felsic granulite, the peak assemblages (M1) are represented by the porphyroblast and matrix minerals (garnet + orthopyroxene + biotite + plagioclase + quartz ± K-feldspar) as well as accessory minerals in the matrix (zircon + monazite + apatite + pyrite), the post-peak assemblages (M2) are characterized by “red-eye socket” symplectites (garnet + plagioclase + quartz) rimming the orthopyroxene porphyroblast, and the final retrograde assemblages (M3) are marked by the biotite-calcite intergrowth. Geothermobarometric computation suggests that the M1, M2 and M3 assemblages of the mafic granulite were formed under 〈em〉P-T〈/em〉 conditions of ∼800 to 860 °C/∼6 to 10 kbar, ∼620 to 700 °C/11 to 12 kbar and ∼590 to 660 °C/4 to 6 kbar〈em〉,〈/em〉 respectively, suggesting that these granulites record anticlockwise 〈em〉P-T〈/em〉 paths including final nearly isothermal decompression (ITD) segments, indicative of orogenic process. For the felsic granulite, metamorphic 〈em〉P-T〈/em〉 conditions of the M1 and M3 assemblages were estimated to be ∼680 to 750 °C/6–8 kbar and ∼670 to 680 °C/5 kbar〈em〉,〈/em〉 respectively, also including ITD process. The widely penetrative gneissosity of the granulite and these 〈em〉P-T〈/em〉 paths, suggest a collisional event of cold nappes overthrusting on hot ones or hot nappes being buried/subducted into cold ones and finally experienced fast tectonic exhumation. High-precision SIMS and LA-ICP-MS U-Pb dating of metamorphic zircon of the granulite suggest that the metamorphism occurred at ∼2.5 Ga. These data confirm that the Miyun metamorphic complex experienced a Neoarchean collisional event within the Eastern Block of the North China Craton.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Geoderma, Volume 337〈/p〉 〈p〉Author(s): R. Calvelo Pereira, M. Camps Arbestain, F.M. Kelliher, B.K.G. Theng, S.R. McNally, F. Macías, F. Guitián〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We have investigated the effect of supercritical drying (SD) on the porosity and the BET-N〈sub〉2〈/sub〉 specific surface area (SSA) of five allophane-rich and three non-allophanic topsoils. The contribution of organic matter (OM) and short-range ordered (SRO) constituents to the nanoscale porosity (〈100 nm size) and SSA was also evaluated following chemical treatments to oxidise OM and then remove the SRO phase. The average pore volume and SSA of the soils, measured after SD, are greater than the values obtained after air drying. For soils that are rich in SRO constituents, oxidation of OM leads to an increase in SSA. This observation is attributed to the unblocking of pore necks previously covered by OM, while the subsequent removal of SRO constituents causes a sharp decrease in SSA. The SRO constituents containing oxalate-extractable Al, are the major contributors to the SSA of the inorganic fraction. Besides confirming that SD can help preserve the nanoscale porosity of allophane-rich soils, the results highlight the contribution of SRO constituents to the SSA of soils and their ability to accumulate OM.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Geochemistry, Volume 99〈/p〉 〈p〉Author(s): M. Lanzoni, W.G. Darling, W.M. Edmunds〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Like many dryland regions around the world, the Butana Region of Sudan is almost entirely dependent on groundwater, and its main source of recharge comes from the highly variable 150–200 mm/yr rain that arrives mostly during a three-month rainy season. These rains cause ephemeral wadis to flow and flood, and provide a critical component of shallow aquifer replenishment.〈/p〉 〈p〉This study uses water table fluctuations along a 20 km wadi reach and chemical and stable isotopic tracers in 27 shallow (〈40 m) and 6 deep (70–170 m) wells to show differences between mean recharge in the alluvial aquifer, estimated as 38–105 mm/yr, and the basal Nubian sandstone aquifer unit at 13–36 mm/yr. This study suggests while groundwater from the Nubian sandstone is predominantly palaeowater of −8 to −6‰ δ〈sup〉18〈/sup〉O formed during a wetter, early-Holocene climate, modern recharge does reach the Nubian sandstone aquifer unit in areas 〈0.3 km from the wadi. An upstream dam may also focus this wadi-directed recharge.〈/p〉 〈p〉In the 1980s, conjunctive use of major and trace geochemistry, isotope, and physical hydrology in the study of wadi recharge was only beginning to gain traction as a sub-discipline, and the study of Edmunds et al. (1987) in the Abu Delaig area paved the way for hydrogeochemical studies in unmonitored dryland catchments around the world. Thirty years on from that study, the local population has grown tenfold, water extraction has increased to accommodate mining, and an upstream dam has been built. This study, conducted in a 400 km〈sup〉2〈/sup〉 subset of the original Lower Atbara Basin study, answers a previously unanswered question about wadi recharge to the deeper, Nubian sandstone aquifer unit and offers a unique three-decade perspective on groundwater development in a rural, arid environment expanding beyond its margin of groundwater sustainability.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Environmental Research, Volume 168〈/p〉 〈p〉Author(s): Cheng-Yang Hu, Yuan Fang, Feng-Li Li, Bao Dong, Xiao-Guo Hua, Wen Jiang, Heng Zhang, Yong Lyu, Xiu-Jun Zhang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Air pollution has been evaluated as a possible risk factor for Parkinson's disease (PD), but, the present results are inconsistent and have not been combined. We performed a systematic review and meta-analysis to estimate the association between long-term exposure to ambient air pollution and PD, given the nature of disease etiology. A total of 10 studies were identified by searching Web of Science, Science Direct, and PubMed before October 2017. We found a significantly increased risk of PD with 10 parts per billion (ppb) increase in nitrogen oxides (NO〈sub〉x〈/sub〉) exposure (relative risk (RR) = 1.06; 95% confidence interval (CI): 1.04, 1.09). The pooled RR for the association between carbon monoxide (CO) exposure, 1 parts per million (ppm) increment, and the risk of PD was 1.65 (95% CI: 1.10, 2.48). The pooled RRs for the association between nitrogen dioxide (NO〈sub〉2〈/sub〉) and ozone (O〈sub〉3〈/sub〉) exposure per 1 ppb increment, and the risk of PD were 1.01 (95% CI: 1.00, 1.03) and 1.01 (95% CI: 1.00, 1.02), respectively. There was a significant heterogeneity in the meta-analysis for fine particulate matter (PM〈sub〉2.5〈/sub〉), NO〈sub〉2〈/sub〉, sulfur dioxide (SO〈sub〉2〈/sub〉), and CO. We concluded that NO〈sub〉2〈/sub〉, NO〈sub〉x〈/sub〉, CO and O〈sub〉3〈/sub〉 exposure were associated with an increased risk of PD, although there is high risk of bias. The dose-response effects evaluated by high-quality studies are needed. Researches should be expanded to low- and/or middle- income countries where indoor and outdoor air pollution are high.〈/p〉〈/div〉 〈div〉 〈h6〉Capsule〈/h6〉 〈p〉Long-term exposure to ambient NO〈sub〉2〈/sub〉, NO〈sub〉x〈/sub〉, CO and O〈sub〉3〈/sub〉 can increase the risk of Parkinson's disease.〈/p〉 〈/div〉

Description: 〈p〉Publication date: Available online 1 November 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Fuzzy Sets and Systems〈/p〉 〈p〉Author(s): Michal Holčapek〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this article, we propose an axiomatic system for fuzzy “cardinality” measures (referred to as fuzzy c-measures for short) assigning to each finite fuzzy set a generalized cardinal that expresses the number of elements that the fuzzy set contains. The system generalizes an axiomatic system introduced by J. Casasnovas and J. Torrens (2003). We show that each fuzzy c-measure is determined by two appropriate homomorphisms between the reducts of residuated-dually residuated (rdr-)lattices. For linearly ordered rdr-lattices, we prove that each fuzzy c-measure is a product of a non-decreasing and a non-increasing fuzzy c-measure, which indicates that there is a close relation between fuzzy c-measures and FGCount, FLCount and FECount provided by L.A. Zadeh (1983) and generalized by M. Wygralak (2001). Finally, the relationship of fuzzy c-measures to graded equipollence introduced in the first part of this contribution is analyzed.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Non-Crystalline Solids, Volume 501〈/p〉 〈p〉Author(s): Joanna Pisarska, Marta Sołtys, Joanna Janek, Agata Górny, Ewa Pietrasik, Tomasz Goryczka, Wojciech A. Pisarski〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Oxyfluoride lead-based and lead-free germanate glasses were heat-treated in order to fabricate transparent glass-ceramics. Cubic β-PbF〈sub〉2〈/sub〉 nanocrystals are well formed during crystallization of lead germanate glass. The up-conversion luminescence spectra of Er〈sup〉3+〈/sup〉 ions in lead germanate glass-ceramic system are enhanced significantly due to partial incorporation of the optically active ions into fluoride crystalline phase. These effects are not significant in oxyfluoride lead-free germanate glass after heat treatment process. The crystallization of barium gallo-germanate glass with BaF〈sub〉2〈/sub〉 is more complex and the presence of four crystalline phases BaF〈sub〉2〈/sub〉, BaO, Ba〈sub〉3〈/sub〉Ga〈sub〉2〈/sub〉Ge〈sub〉4〈/sub〉O〈sub〉14〈/sub〉 and GeO〈sub〉2〈/sub〉 was verified by X-ray diffraction measurements.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 216〈/p〉 〈p〉Author(s): Xinjiang Hu, Weixuan Wang, Guangyu Xie, Hui Wang, Xiaofei Tan, Qi Jin, Daixi Zhou, Yunlin Zhao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel ternary composite of graphitic carbon nitride (g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉)/graphene oxide (GO) sheets/BiFeO〈sub〉3〈/sub〉 (CNGB) with highly enhanced visible-light photocatalytic activity toward Cr(VI) photoreduction is prepared and characterized. The characterization and photocatalysis experiments corroborate its reasonable band gap, efficient charge separation and transfer, widened visible-light adsorption, easy solid-liquid separation, good stability and superior catalytic activity of CNGB. Three CNGB samples with different ratios of g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉 and BiFeO〈sub〉3〈/sub〉 (CNGB-1, -2, -3 with 2:4, 3:3, and 4:2, respectively), though possessing different adsorption ability, eventually remove all Cr(VI) ions via photocatalysis within 90 min. The catalytic efficiency of the composite is the highest at pH 2; increases in pH decrease the catalytic ability. The inorganic anions such as SO〈sub〉4〈/sub〉〈sup〉−〈/sup〉, Cl〈sup〉−〈/sup〉, and NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉 only slightly affects the photocatalytic process. The matching of the band structure between BiFeO〈sub〉3〈/sub〉 and g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉 generates efficient photogenerated electron migration from the conduction band of g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉 to that of BiFeO〈sub〉3〈/sub〉, which is also facilitated by the electron bridging and collecting effects of GO, and holes transfer from the valence band of BiFeO〈sub〉3〈/sub〉 to that of g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉, yielding the efficient separation of photogenerated electron-hole pairs and the subsequent enhancement of photocatalytic activity. The research provides a theoretical basis and technical support for the development of photocatalytic technologies for effective application in wastewater treatment and Cr-contaminated water restoration.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 216〈/p〉 〈p〉Author(s): F. Faghihzadeh, N.M. Anaya, H. Hadjeres, T.B. Boving, V. Oyanedel-Craver〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉This study present assessed the effect of UV pulsed light (PL) on microbial and organic pollutants using two spiral lamps were used, i.e., PL1 and PL2 lamps, with wavelength cut-offs of 190 and 240 nm, respectively. Overall, our study demonstrated that pulsed UV light impacts several microbial biomolecules and degrades polycyclic aromatic hydrocarbons (PAHs) in aqueous solution. In microbial inactivation by PL2, temporary changes of bacterial cellular components, specifically proteins, were observed, but the compositional changes of bacteria that were exposed to PL1 were permanent due to ozonolysis. PL1 irradiation caused greater deactivation of the bacteria than PL2 irradiation due to the generation of ozone. The higher efficacy of PL1 in terms of membrane disruption, reduction of respiration rate, and reduction of growth rate was due to the production of ozone during the irradiation period. The bacteria that were irradiated with both PL lamps regrew due to photoreactivation, such as an enzymatic DNA-repair mechanism.〈/p〉 〈p〉The PAH degradation kinetics indicate that higher molecular weights degraded faster than those with lower molecular weights. For both lamps, the degradation of naphthalene and fluorene was first order, whereas second order for pyrene and anthracene. Any effect of ozonolysis on the PAH degradation rates was not apparent, which indicated that photolysis was the primary degradation pathway. PAH solutions treated with both pulsed UV lamps did not result in a toxicity effect on the bacteria.〈/p〉 〈/div〉 〈/div〉