Spin Hall Conductance of the Two Dimensional Hole Gas in a Perpendicular Magnetic Field

The charge and spin Hall conductance of the two-dimensional hole gas within the Luttinger model with and without inversion symmetry breaking terms in a perpendicular magnetic field are studied, and two key phenomena are predicted. The sign of the spin Hall conductance is modulated periodically by the external magnetic field, which means a possible application in the future. Furthermore, a resonant spin Hall conductance in the two-dimensional hole gas with a certain hole density at a typical magnetic field is indicated, which implies a likely way to firmly establish the intrinsic spin Hall effect. The charge Hall conductance is unaffected by the spin-orbit coupling.Comment: accepted for publication in Phys. Rev. B; 6 pages, 4 figure

Needy or Greedy? The Social Psychology of Individuals Who Fraudulently Claim Unemployment Benefits

This study explored the relationships between diverse social psychological and economic variables and self‐reported and officially documented unemployment benefit fraud. Two groups receiving unemployment benefit were studied; a fraudulent group of 45 individuals and an honest group of 51 individuals. Interview measures of financial strain, social norms, opportunity for fraud, social controls, personal strain, personal orientation, perceived risk of punishment, and intolerance of fraud were obtained. The results of univariate and regression analyses revealed that although financial strain and social norms did not differ between the two groups, the fraudulent group had more opportunity, were less well educated, were more alienated and inclined to take risks, and had more positive attitudes toward a variety of kinds of fraud. Copyrigh

Novel low energy hydrogen–deuterium isotope breakthrough separation using a trapdoor zeolite

AbstractCs-chabazite, a type of zeolite with caesium counter-cations, possesses interesting gas separation properties due to a highly selective molecular “trapdoor” effect. Herein the use of this material for H2/D2 isotope separation is demonstrated. Isotope separation was achieved using breakthrough separation with a single pass through a packed bed at moderate temperatures (293K) and pressures (0.17MPa) when one species was in a sufficiently low concentration. The breakthrough separation curves were successfully modelled using the Thomas kinetic breakthrough model and the Yoon and Nelson kinetic breakthrough model, where working transferable kinetic rate constants were developed. Use of this material for hydrogen isotope separation would significantly lower the total energy demand compared with current hydrogen isotope separation techniques such as cryogenic distillation and is applicable to separating out low concentrations of D2 (0.0156%) present in standard grade H2

Electroreduction of CO2/CO to C2 products: process modeling, downstream separation, system integration, and economic analysis.

Direct electrochemical reduction of CO2 to C2 products such as ethylene is more efficient in alkaline media, but it suffers from parasitic loss of reactants due to (bi)carbonate formation. A two-step process where the CO2 is first electrochemically reduced to CO and subsequently converted to desired C2 products has the potential to overcome the limitations posed by direct CO2 electroreduction. In this study, we investigated the technical and economic feasibility of the direct and indirect CO2 conversion routes to C2 products. For the indirect route, CO2 to CO conversion in a high temperature solid oxide electrolysis cell (SOEC) or a low temperature electrolyzer has been considered. The product distribution, conversion, selectivities, current densities, and cell potentials are different for both CO2 conversion routes, which affects the downstream processing and the economics. A detailed process design and techno-economic analysis of both CO2 conversion pathways are presented, which includes CO2 capture, CO2 (and CO) conversion, CO2 (and CO) recycling, and product separation. Our economic analysis shows that both conversion routes are not profitable under the base case scenario, but the economics can be improved significantly by reducing the cell voltage, the capital cost of the electrolyzers, and the electricity price. For both routes, a cell voltage of 2.5 V, a capital cost of $10,000/m2, and an electricity price of <$20/MWh will yield a positive net present value and payback times of less than 15 years. Overall, the high temperature (SOEC-based) two-step conversion process has a greater potential for scale-up than the direct electrochemical conversion route. Strategies for integrating the electrochemical CO2/CO conversion process into the existing gas and oil infrastructure are outlined. Current barriers for industrialization of CO2 electrolyzers and possible solutions are discussed as well

Leaf yellowing of the wheat cultivar Mace in the absence of yellowspot disease

The wheat variety Mace is currently dominating the southern wheat growing regions of Australia. It is high yielding in most environments and resistant to many diseases including yellow spot (also known as tan spot). However, observations of foliar yellowing of Mace have recently been reported in the field. This has raised concerns over a possible breakdown of resistance to yellow spot, which is caused by the necrotrophic fungal pathogen Pyrenophora triticirepentis. West Australian field samples of yellowing Mace leaves were evaluated for P. triticirepentis infection, and this pathogen was determined to be absent. Instead, Alternaria spp. were isolated from the wheat leaves. Pathogenicity assays showed that the recovered Alternaria spp. were unable to cause disease symptoms on Mace. Furthermore, spontaneous foliar lesions were observed in Mace grown in the absence of pathogens. It is therefore likely that such yellowing is a physiological trait, which will not respond to fungicide application. A marginal impact on yield cannot be excluded