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A novel aluminothermic reduction combined with deoxidation process was developed in this research to prepare low-oxygen Ti-6Al-4V alloy powder. First, with Al and Al-V alloy powders as reducing agents and additives, crude Ti-6Al-4V alloy powder was fabricated by reduction-vacuum distillation using Na 2 TiF 6 as a titanium source. The aluminothermic reduction process was investigated by TG-DSC technique, and the thermal kinetic parameters of the reaction process were calculated by the Kissinger method. The oxygen content of the crude Ti-6Al-4V alloy powder with a coral-like porous structure was detected as 0.366 %. Furthermore, the existential states of the oxygen contained in the crude product powder was analyzed using XPS. The results indicated that the oxygen existed in three chemical states: metal oxides, defective oxygen, and adsorbed oxygen. Therefore, the deoxygenation of the crude Ti-6Al-4V alloy powder with calcium as a deoxidizer was carried out at 900 °C. As a result, the final Ti-6Al-4V powder with an oxygen content of approximately 822 ppm could be obtained. The contents of Ti, Al, V, Fe, and O in the obtained Ti-6Al-4V powders met the requirements of GB/T 3620.1−2016. This work had demonstrated the feasibility of preparing Ti-6Al-4V alloy powder by the novel aluminothermic reduction combined with deoxidation process. • Low-oxygen Ti-6Al-4V powder was prepared from metallurgical-grade materials by a short process with non-pollution. • Mechanism and kinetic analysis of the rapid exothermic reduction process were preliminary investigated. • The oxygen content in the final Ti-6Al-4V powder can be as low as 822 ppm. • A short process for preparing of low-oxygen Ti-6Al-4V powder was proved to be feasible. [ABSTRACT FROM AUTHOR]

To improve the performance of lithium-ion batteries, the functional separators were developed by coating water-based polyvinylidene fluoride (PVDF) powder particles solution using polyvinyl alcohol as the binder on both sides of a conventional polypropylene (PP) microporous membrane by means of simple dipping. The electrochemical performance was tested and compared with that of pure PP membrane. It was found that the PVDF powder particles accumulated and scattered on the surface of PP membrane. Many voids existed among the powder particles. The thermal shrinkage percent tested at 130 °C for 1 h was decreased from 59.4% to 12.7%, whereas the electrolyte uptake was increased from 80% to 140%. The separator coated with 10% solid content of PVDF particles exhibited the best electrochemical performance, including the cycling performance and rate capability. The coated PVDF component not only decreased the interface resistance but also increased the ionic conductivity, owing to the high strong affinity of PVDF toward polar solvents and the voids among the PVDF particles to afford the passage for Li-ions. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between U.S. state-level CO 2 emissions and two measures of income inequality: the income share of the top 10% and the Gini coefficient. Each of the inequality measures, which focus on unique characteristics of income distributions, is used to evaluate the arguments of different analytical approaches. Results of the longitudinal analysis for the 1997 to 2012 period indicate that state-level emissions are positively associated with the income share of the top 10%, while the effect of the Gini coefficient on emissions is non-significant. The statistically significant relationship between CO 2 emissions and the concentration of income among the top 10% is consistent with analytical approaches that focus on political economy dynamics and Veblen effects, which highlight the potential political and economic power and emulative influence of the wealthy. The null effect of the Gini coefficient is generally inconsistent with the marginal propensity to emit approach, which posits that when incomes become more equally distributed, the poor will increase their consumption of energy and other carbon-intensive products as they move into the middle class. [ABSTRACT FROM AUTHOR]

We report the effect of neighboring transitions on the transformation between electromagnetically induced transparency (EIT) and two-photon absorption (TPA) in an open multi-level ladder type system of 87Rb atom, the EIT peak exhibits split and asymmetric line feature owing to a neighboring transition line with a stronger relative hyperfine transition strength factor. By comparing the signals of the 5 S 1 / 2 − 5 P 3 / 2 − 5 D 3 / 2 , 5 / 2 transitions when increasing the power of the coupling laser, it can be found that avoiding neighboring effects due to Doppler broadening in a real atom, a lower decay rate of the excited state and a higher hyperfine transition strength ratio between the coupling and probe lasers are the crucial factors that enhance the transformation efficiency between TPA and EIT and the resolution of the switched spectra. Detailed theoretical calculations, considering the crucial factors, are consistent with the experimental results. • Study the mechanism of transformation between Two-photon absorption and Electromagnetically induced transparency. • Determine the origin of splitting and asymmetric features in electromagnetically induced transparent signals. • Confirm the crucial factors for achieving high-precision and high-efficiency switching spectral lines. [ABSTRACT FROM AUTHOR]

In this paper, a stellated carbon filler (S-filler) through passivation of the surfaces of carbon nanotubes and carbon black (CNTs/CB) was fabricated, and the corresponding thermal conductive composites of polypropylene (blended with alumina) (PP/Al 2 O 3 ) incorporated with S-filler were fabricated. When adding 15 wt% S-filler, the composite shows an DC electrical resistivity as high as 8.34 × 10 11 Ω cm and high thermal conductivity about 0.68 W/m·k. The composite using the new carbon filler as hybrid part shows a higher thermal conductivity and electric insulation. The rheological test also shows that the percolation network is not formed by the S-filler. This work offers a novel route for the design of thermally conductive, but electrically insulative composites with polymer as a matrix. [ABSTRACT FROM AUTHOR]

Ambient air pollution, in the form of fine particulate matter (PM 2.5), poses serious population health risks. We estimate cross-national longitudinal models to test whether the negative relationship between life expectancy and PM 2.5 concentration is larger in nations with higher levels of income inequality. The dependent variable is average life expectancy at birth, and the focal predictor variables include PM 2.5 concentration, income inequality, and the two-way interaction between them. We also estimate the average marginal effects of PM 2.5 concentration from low to high values of income inequality, and the predicted values of life expectancy from low to high values of PM 2.5 concentration and income inequality. Results indicate that the negative relationship between life expectancy and PM 2.5 concentration is larger in nations with higher levels of income inequality, and the reductions in predicted life expectancy are substantial when both PM 2.5 concentration and income inequality are high. We suggest that the theoretical principles of Power, Proximity, and Physiology help explain our findings. This study underscores the importance in considering the multiplicative impacts of environmental conditions and socioeconomic factors in the modeling of population health. Unlabelled Image • PM 2.5 poses serious population health risks throughout the world. • We estimate longitudinal models of life expectancy for 136 nations. • Average life expectancy is negatively associated with PM 2.5 concentration. • Income inequality amplifies the negative association between them. [ABSTRACT FROM AUTHOR]