ALBERT

Description: Hydrodynamics characteristics like flow pattern, shear rate distribution, power consumption, axial pumping capacity, mixing time, and mixing efficiency of an ellipse gate (EG) impeller were investigated by experimental and numerical methods. The numerical simulation results were validated by experimental data of power consumption and mixing time. Results indicate that the axial pumping number of the EG impeller is larger than that of any other reported large-scale impeller under laminar regime, and that the shear rate formed by this impeller is less sensitive to Reynolds numbers. In-depth analysis reveals the different function of each part of the EG impeller under different flow regimes. This impeller provides an almost similar mixing efficiency like the double-helical ribbon impeller under laminar regime, but much higher mixing efficiency both under transitional and turbulent flow regimes. An ellipse gate impeller was designed for fermentation processes with varying fluid viscosities in order to cover turbulent to transient or even laminar flow regimes in a reactor. Hydrodynamics characteristics were investigated by experimental and numerical methods, indicating excellent mixing properties of this impeller in a wide range of Reynolds numbers.

Description: Aims Road effects from maintenance and traffic have the potential to alter plant communities, but the exact relationships between these effects and changes in plant community composition have not often been studied in diverse environments. To determine the direction and level of community composition changes in saline environment due to road effects, we conducted a study along roads of different ages and in nearby non-road (i.e. natural) areas in the Yellow River Delta, China. Additionally, to potentially elucidate the mechanisms underlying the changes in the richness and composition of plant communities along roads, we evaluated physiochemical changes in soil of roadside and non-road areas. Methods Floristic and environmental data were collected along roadside of different ages and nearby non-road areas. To evaluate plant communities at each site, six 2 m x 2 m quadrats were placed at 3-m intervals along roads and six quadrats were arranged randomly in non-road areas. To determine the difference in plant community composition between roadside and non-road areas, we measured species richness and the abundance of each species, examined species turnover and floristic dissimilarity between the two areas and positioned plant species and sites in an abstract multivariate space. Plant community (species richness, percentage of halophytes) and soil physicochemical properties (pH, salinity, moisture content, bulk density, nitrate and ammonium nitrogen concentration) were compared between roadside and non-road areas (young roadside vs. corresponding non-road areas, old roadside vs. corresponding non-road areas) by using t -tests. Classification and ordination techniques were used to examine the relationship between vegetation and related environmental variables in both roadside and non-road areas. Important Findings For both the young and old roadside areas, species richness in roadside areas was significantly higher than in non-road areas and high floristic dissimilarity values indicated that roadside and non-road areas differed greatly in community composition. In both the young and old roadside areas, the plant communities in roadside areas had lower percentages of halophytes than non-road communities. Correspondence analysis and two-way indicator species analysis showed that halophytes dominated in the non-road areas, while a number of typical non-salt-tolerant species dominated in the roadside areas. Compared to non-road areas, activities associated with roads significantly decreased soil moisture, bulk density and salinity and increased soil pH and nitrate content. Forward selection for the environmental variables in canonical correspondence analysis showed that soil salinity was the most important factor related to the variation of species composition between roadside and non-road areas. Our study demonstrates that road effects have a significant impact on the associated vegetation and soil, and these changes are consistent across roads of different ages in our system.

Description: Author(s): Steven S.-L. Zhang and Shufeng Zhang In a semiconductor heterostructure, the Coulomb interaction is responsible for the electric current drag between two 2D electron gases across an electron impenetrable insulator. For two metallic layers separated by a ferromagnetic insulator (FI) layer, the electric current drag can be mediated by a ... [Phys. Rev. Lett. 109, 096603] Published Wed Aug 29, 2012

Description: Author(s): H. Teng, T. Fujiwara, T. Hoshi, T. Sogabe, S.-L. Zhang, and S. Yamamoto The need for large-scale electronic structure calculations arises recently in the field of material physics, and efficient and accurate algebraic methods for large simultaneous linear equations become greatly important. We investigate the generalized shifted conjugate orthogonal conjugate gradient m... [Phys. Rev. B 83, 165103] Published Wed Apr 06, 2011

Description: Cancer-initiating cells derived from human rectal adenocarcinoma tissues carry mesenchymal phenotypes and resist drug therapies Cell Death and Disease 4, e828 (October 2013). doi:10.1038/cddis.2013.337 Authors: C-W Fan, T Chen, Y-N Shang, Y-Z Gu, S-L Zhang, R Lu, S-R OuYang, X Zhou, Y Li, W-T Meng, J-K Hu, Y Lu, X-F Sun, H Bu, Z-G Zhou & X-M Mo

Description: Author(s): A. I. Figueroa, G. van der Laan, L. J. Collins-McIntyre, S.-L. Zhang, A. A. Baker, S. E. Harrison, P. Schönherr, G. Cibin, and T. Hesjedal Ferromagnetically doped topological insulators with broken time-reversal symmetry are a prerequisite for observing the quantum anomalous Hall effect. Cr-doped (Bi,Sb)2(Se,Te)3 is the most successful materials system so far, as it combines ferromagnetic ordering with acceptable levels of additional b... [Phys. Rev. B 90, 134402] Published Fri Oct 03, 2014

Description: Effect of the metal/oxide interface on spin-dependent transport properties in perpendicular [Co/Pt] 3 multilayers was investigated. The saturation Hall resistivity ( ρ xy ) is significantly increased by 45% with 1.4 nm thick CoO layer inserted at the top Co/MgO interface; whereas it is increased only 25% with 1 nm thick CoO layer at the bottom MgO/Co interface. The interfacial structures characterized by X-ray photoelectron spectroscopy show that the MgO/Co interface and Co/MgO interface including chemical states play a dominant role on spin-dependent transport, leading to different anomalous Hall behavior.

Description: Author(s): Steven S.-L. Zhang and Shufeng Zhang Exchange interaction between conduction electrons and magnetic moments at magnetic interfaces leads to mutual conversion between spin current and magnon current. We introduce a concept of spin convertance which quantitatively measures magnon current induced by spin accumulation and spin current crea... [Phys. Rev. B 86, 214424] Published Wed Dec 26, 2012

Description: Magnetoresistance (MR) effects are at the heart of modern information technology. However, future progress of giant and tunnelling MR based storage and logic devices is limited by the usable MR ratios of currently about 200% at room-temperature. Colossal MR structures, on the other hand, achieve their high MR ratios of up to 106% only at low temperatures and high magnetic fields. We introduce the extraordinary Hall balance (EHB) and demonstrate room-temperature MR ratios in excess of 31,000%. The new device concept exploits the extraordinary Hall effect in two separated ferromagnetic layers with perpendicular anisotropy in which the Hall voltages can be configured to be carefully balanced or tipped out of balance. Reprogrammable logic and memory is realised using a single EHB element. PACS numbers: 85.75.Nn,85.70.Kh,72.15.Gd,75.60.Ej. Scientific Reports 3 doi: 10.1038/srep02087

Description: We present the results of high spatial resolution observations in the 1.1-mm waveband with the Submillimetre Array (SMA) towards the protocluster G10.6–0.4. The 1.1-mm continuum emission reveals seven dense cores. Redshifted absorption dips are seen in the HCN (3–2) lines in these cores, suggesting infalling of gas towards the dense cores. This is the first time that infall has been seen towards multiple sources in a protocluster. We also identified four infrared point sources in this region, which are most likely Class 0/I protostars. Two jet-like structures are also identified from Spitzer /Infrared Array Camera (IRAC) images. The dense core located in the centre has a much larger mass than the off-centre cores. The clump is in overall collapse and the infall motion is supersonic. The standard deviations of core velocities and the velocity differences between the cores and the cloud/clump are all larger than the thermal velocity dispersion. The picture of G10.6–0.4 seems to favour the ‘competitive accretion’ model, but this needs to be tested through further observations.