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Presents review papers in Journal of Material Science in the U.S. "Structure and Properties of Glass-like Carbon," by L.A. Pesin; "Mechanical Properties of Ice and Snow," by J.J Petrovic; "Stability of Nanostructured Materials," by R.A. Andrievski; "Models in Thermoluminescence," by C. Furetta and G. Kitis; Others.

Using the modified-single fiber test developed by Holmes and colleagues (J Appl Polym ), a detailed analysis of fibers extracted from soft body armor comprised of polybenzoxazole (PBO) fibers was performed. The data indicate that hydrolytic degradation of these ballistic fibers is accompanied by degradation associated with folding (or fatigue-induced degradation) and an undefined degradation mechanism associated with vest use that appears to target the horizontal yarns of the alternating 0°/90° woven layers. These additional failure mechanisms have the potential to create localized regions in the PBO soft body armor which are significantly lower than the homogeneous degradation expected from uniform hydrolysis. Results also indicate that the absence of ballistic penetrations in the initial study conducted at the National Institute of Standards and Technology may be associated with using the properties of the fibers from the back panel of a compromised vest as representative of the properties in the front panel that was penetrated. Analysis of a field return vest showed the front panel to be significantly more degraded than the back panel. [ABSTRACT FROM AUTHOR]

With growing demands of energy and enormous consumption of fossil fuels, the world is in dire need of a clean and renewable source of energy. Hydrogen (H2) is the best alternative, owing to its high calorific value (144 MJ/kg) and exceptional mass-energy density. Being an energy carrier rather than an energy source, it has an edge over other alternate sources of energy like solar energy, wind energy, and tidal energy, which require a constant energy source dependent upon weather conditions. However, its utilization as an energy carrier has not yet been commercialized due to its poor storage performance, which is attributed to low gravimetric and volumetric densities of adsorbed hydrogen at ambient temperature and technological limitations in meeting the stringent parameters set by Department of Energy, USA. With exceptionally large surface area (2630 m2/g), porous nature, lightweight, and high chemical and thermal stability (melting point ~ 4510 K) along with the possibility of economical and scalable production, graphene-based solid-state porous materials have shown promising applications in efficient hydrogen storage. In this context, the present review discusses the recent advances and progress on the utilization of functionalized graphene, graphene oxide, and its derivatives for effective storage of hydrogen, along with important theoretical advancements via DFT calculations, first-principle calculations, and Monte Carlo Simulations, etc. Pristine graphene has poor hydrogen storage characteristics, and addition of dopants like boron and nitrogen or decoration by transition metals significantly improves the performance. In addition, graphene allows the tuning of surface curvature which can help in achieving a reversible hydrogen storage system with fast kinetics. The impact of external stimuli like electric field and strain on electronic structure of graphene is discussed with the applicability in achieving a highly controllable adsorption–desorption system. Finally, the review concludes with life cycle assessment of graphene-engineered composites for effective hydrogen storage applications, along with their energy and environmental implications. [ABSTRACT FROM AUTHOR]