Phosphorene-AsP Heterostructure as a Potential Excitonic Solar Cell Material - A First Principles Study

Solar energy conversion to produce electricity using photovoltaics is an emerging area in alternative energy research. Herein, we report on the basis of density functional calculations, phosphorene/AsP heterostructure could be a promising material for excitonic solar cells (XSCs). Our HSE06 functional calculations show that the band gap of both phosphorene and AsP fall exactly into the optimum value range according to XSCs requirement. The calculated effective mass of electrons and holes show anisotropic in nature with effective masses along ${\Gamma}$-X direction is lower than the ${\Gamma}$-Y direction and hence the charge transport will be faster along ${\Gamma}$-X direction. The wide energy range of light absorption confirms the potential use of these materials for solar cell applications. Interestingly, phosphorene and AsP monolayer forms a type-II band alignment which will enhance the separation of photogenerated charge carriers and hence the recombination rate will be lower which can further improve its photo-conversion efficiency if one use it in XSCs

Examining the resilience of UAE to decline in oil prices - the case of the insurance sector

The sharp fall in oil prices from $112/barrel in 2014 to$59/barrel in 2019 impacted many economies in the world in both positive and negative manner. United Arab Emirates (UAE) has been seeking diversification to reduce its reliance on oil revenues and expects higher growth from non-oil revenues in 2020. This study aims to examine the resilience of UAE to decline in oil prices with the insurance sector as a representative sector of the economy This study involves calculations and comparisons of financial ratios pre- and post-fall in oil prices in the UAE. Parametric test results indicate that while the change in investment and efficiency ratios is statistically significant, profitability, efficiency and gearing ratios have been quite stable in the period. Despite the overall slowdown in the insurance industry, the sector has been mostly resistant to the drop in oil prices. This resilience can be attributed to the ongoing efforts of UAE leadership to diversify away from an oil-based economy

Macroeconomic and bank specific determinants of non-performing loans in UAE conventional bank

This paper uses panel data methodology including Random Effects model to identify the bank-specific determinants and macroeconomic determinants of non-performing loans in the United Arab Emirates (UAE) conventional banks for the period 2008-2015. Among the bank-specific determinants, non-performing loans (NPL, t-1) indicate a significant positive relationship with NPL and liquidity ratio indicate a significant negative relationship with NPL, whereas capital adequacy ratio and return on assets was found to have an insignificant relationship due to the robust banking regulations in UAE. All the macroeconomic determinants, namely, gross domestic product, growth, inflation, domestic credit to private sector, unemployment and government debt appeared to be insignificant in determining the level of NPLs, suggesting that the crisis is more intrinsic to internal issues within the corporates and not related to macroeconomic factors

The Gene Ontology: enhancements for 2011

The Gene Ontology (GO) (http://www.geneontology.org) is a community bioinformatics resource that represents gene product function through the use of structured, controlled vocabularies. The number of GO annotations of gene products has increased due to curation efforts among GO Consortium (GOC) groups, including focused literature-based annotation and ortholog-based functional inference. The GO ontologies continue to expand and improve as a result of targeted ontology development, including the introduction of computable logical definitions and development of new tools for the streamlined addition of terms to the ontology. The GOC continues to support its user community through the use of e-mail lists, social media and web-based resources

Pressure Carboxylation of Lignitic Minerals with Carbon Dioxide

Leonardite and lignite were carboxylated by the Kolbe-Schmitt reaction in order to increase the acidity and hence the cation exchange capacity. A larger carboxyl group content would increase solubility and effectiveness in commercial application such as a thinner for oil-well drilling fluids. The carboxylation was performed in a heated autoclave under a high carbon dioxide pressure. The Kolbe-Schmitt reaction was used in an anhydrous medium and in a slurry medium and in a modification developed by Marasse using anhydrous potassium carbonate. The reaction material consisted of moisture free, fine powdered potassium salts of leonardite and lignite. Temperature was varied from 100°C to 180°C and the initial carbon dioxide pressure from 225 psig to 900 psig. The time of reaction was also varied between 4 and 24 hours. The extent of reaction was evaluated from changes in total acidity, hydroxyl acidity and carboxyl acidity of the treated material. The maximum increase obtained in carboxyl acidity was 39 percent and that in total acidity was 89 percent of the increase predicted on the basis of complete ortho substitution to all existing hydroxyl groups. The optimum conditions found were at 150°C temperature and a pressure of 1060 psig for 8 hours

Examining the linkage between class attendance at university and academic performance in an international branch campus setting

The relationship between class attendance and academic performance has been an important area of research, with a positive association being posited between the two. The setting for our study is an International Branch Campus (IBC) of a British university that needs to demonstrate the quality of its service delivery both to the parent institution and to the fee-paying students. We employ a dataset of over 900 students in an undergraduate degree programme and subject it to statistical techniques, namely quantile regression and two-stage quantile regression. Our results show that attendance has a beneficial influence on academic performance and this benefit persists at higher percentile of grades. We propose that IBCs could consider an attendance policy that encourages students to attend classes

A Bootstrapping Approach for Generating Maximally Path-Entangled Photon States

We propose a bootstrapping approach to generation of maximally path-entangled states of photons, so called ``NOON states''. Strong atom-light interaction of cavity QED can be employed to generate NOON states with about 100 photons; which can then be used to boost the existing experimental Kerr nonlinearities based on quantum coherence effects to facilitate NOON generation with arbitrarily large number of photons all within the current experimental state of the art technology. We also offer an alternative scheme that uses an atom-cavity dispersive interaction to obtain sufficiently high Kerr-nonlinearity necessary for arbitrary NOON generation