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The Effect of Ion Implanting on Hydrogen Entry into Metals
The effectiveness of platinum ion implanting in mitigating hydrogen entry into 4340 steel is measured and quantified. Data are presented to compare the extent of hydrogen absorption by the substrate during electrolytic hydrogen charging of platinum ion-implanted and unimplanted 4340 steel substrates. Several implanting conditions were used in processing the samples, and the surface-limited mass-transfer coefficient was calculated for each case and used to quantify the effectiveness of each treatment in reducing hydrogen absorption. It is shown that the underlying mechanism for reducing hydrogen absorption by platinum ion-implanted substrates is the catalytic effect of platinum that favors hydrogen evolution at the steel\u27s surface over hydrogen absorption by the metal. Although scattering experiments with low energy helium ions suggest that the platinum content in the first monolayer of platinum-implanted steels is small, the ability of Pt to catalyze the hydrogen evolution reaction is still strong enough to significantly reduce the quantity of hydrogen that enters the metal
Erratum: Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017
Interpretation: By quantifying levels and trends in exposures to risk factors and the resulting disease burden, this assessment offers insight into where past policy and programme efforts might have been successful and highlights current priorities for public health action. Decreases in behavioural, environmental, and occupational risks have largely offset the effects of population growth and ageing, in relation to trends in absolute burden. Conversely, the combination of increasing metabolic risks and population ageing will probably continue to drive the increasing trends in non-communicable diseases at the global level, which presents both a public health challenge and opportunity. We see considerable spatiotemporal heterogeneity in levels of risk exposure and risk-attributable burden. Although levels of development underlie some of this heterogeneity, O/E ratios show risks for which countries are overperforming or underperforming relative to their level of development. As such, these ratios provide a benchmarking tool to help to focus local decision making. Our findings reinforce the importance of both risk exposure monitoring and epidemiological research to assess causal connections between risks and health outcomes, and they highlight the usefulness of the GBD study in synthesising data to draw comprehensive and robust conclusions that help to inform good policy and strategic health planning
The effect of thickness on the structural and optical properties of nano Ge-Te-Cu films
Quartz was used as a substrate to hold different film thicknesses of Ge0.15Te0.78Cu0.07 within range 100–500 nm prepared by thermal evaporation technique. Films are still amorphous up to 200 nm and turn to more ordered nano polycrystalline one by ascending the values of film thickness up to 500 nm. Films turn to crystalline phase due to annealing. The relation of resistance and temperature shows phase transformation. Optical constants; refractive index, n absorption coefficient, α single-oscillator energy, Eo dispersion energy, Ed lattice dielectric constant, εL infinite wavelength dielectric constant, ε∞ the ratio of the carrier concentration to the effective mass, N/m∗ optical conductivity, σ and energy loss function, ELF show decreasing values with thickness up to 200 nm followed by ascending values within range 200–500 nm. It is concluded that the thickness range 100–200 nm introduces more disordered films while 200–500 nm introduces more ordered one. Keywords: GeTeCu alloys, Structural properties, Optical properties, Thickness, Nano materials, Phase change memor