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The studies of large H atom line broadening observed throughout the volume of surface wave generated He-[H.sub.2] and [H.sub.2] microwave plasmas at low pressures are reported. The measurements obtained for the Doppler temperatures corresponding to the H[beta], H[gamma], H[delta] H[epsi] , and H[zeta] line profiles are found to be higher than the rotational temperature of the hydrogen molecular Fulcher-[alpha] band and the Doppler temperature of the 667.1 nm singlet He line.

The hydrogen sensing behavior of porous nanocrystalline zinc ferrite sensing elements is examined. The difference in respective activation energies for response as well as recovery is attributed to the different chemiadsorbed oxygen species in the adsorption sites.

CoFe alloy nanoflakes (NFs) with diameter and thickness on nanoscale are prepared by hydrogen-thermal reduction in Co[Fe.sub.2][O.sub.4] flakes and their effective complex permittivity and permeability are measured. The effective electromagnetic wave absorbing (EMA) band position of the coating with CoFe alloy NFs as fillers is located in the range of 2-4 GHz, while the effective EMA band position of the coating containing CoFe alloy NPs as fillers is located in the range of 8-18 GHz.

The research progress in molecular structural kinetic studies of gas hydrates is examined. The development of new strategies for detecting and producing energy from arctic and oceanic hydrated deposits and producing new materials for hydrogen storage is discussed.

The article studies a magnetogravitational potential to evaluate quantitatively the remaining forces. Findings highlight the critical point of [H.sub.2].

Dihydrogen, methane, and carbon dioxide isotherm measurements are performed on the evacuated forms of seven porous covalent organic frameworks (COFs). The results have placed COFs among the most porous and the best porous adsorbents for hydrogen, methane and carbon dioxide.

Scanning and transmission electron microscopies are used for studying silicon substrate texturing and whisker growth on Si substrates by using pure hydrogen source gas in a tungsten hot filament reactor. The studies have shown that the whiskers are partly crystalline and partly amorphous, which has consisted pure Si with W[Si.sub.2] particles on their tips as well as sometimes being incorporated into their structure.

Raman spectroscopy was used to determine standard enthalpy [Delta] [H.sup.o] and entropy [Delta] [S.sup.o] and evaluate the partial pressures and equilibrium constants for the reaction.from lithium amide and hydrogen to lithium hydride and ammonia at different temperatures. The measurements obtained from Raman intensity could be used to estimate ammonia partial pressures in gaseous products after heat and treatment of lithium amide under hydrogen atmosphere.

The feasibility of combining a carrier that releases hydrogen by endothermic dehydrogenation with a carrier that releases hydrogen by exothermic hydrolysis is described. The strategy of physically mixing two carriers is tested by carrying out the hydrolysis of a variety of amine-boranes and the catalytic dehydrogenation of indoline.

NMR spectrometry is used to assess the line shape and spin-lattice relaxation time [T.sub.1] of the [super 1]H, [super 2]H, and [super 87]Rb nuclei in [Rb.sub.3]H[(S[O.sub.4]).sub.2] and [Rb.sub.3]D[(S[O.sub.4]).sub.2] single crystals. The results revealed that the high conductivities of the crystals at high temperature might be related to both symmetry changes in the H[((S[O.sub.4]).sup.2-]).sub.2] dimers and motion that give rise to a strong temperature dependence of [T.sub.1].

The splitting kinetics of [Si.sub.0.8][Ge.sub.0.2] substrates implanted with H-only or sequentially implanted with He and then with H is studied. The extended physical characterization of the implanted and annealed substrates has provided insights into the mechanism of splitting in [Si.sub.0.8][Ge.sub.0.2].

Prototypical covalent organic frameworks (COFs) have predicted up to 10% excess [H.sub.2] storage capacity in COF-105 at 77 K. The results have shown that the surface area and free volume of COF should be increased in order to increase the maximum [H.sub.2] uptake in COFs.

Ultrafast two dimensional infrared (2D IR) chemical exchange spectroscopy in liquid solutions at room temperature were employed to measure the formation and dissociation kinetics of a series of triethylsilanol/solvent weakly hydrogen bonding complexes with ethalpies ranging from -1.4 to -3.3 kcal/mol. The results revealed that the off-diagonal chemical exchange peaks have shapes that are a combination of the absorption line shapes of the species that give rise to the diagonal peaks.

Several numerical and analytical studies are conducted to explain the thermally driven combustion oscillatory behaviors of methane and hydrogen in a perfectly stirred reactor. These oscillations are shown to occur at the extinction turning point of the hysteresis curve.

The synthesis of an open-cage [C.sub.70] derivative, which encapsulates two [H.sub.2] molecules in high yield, is reported. The results from the studies provide insight into the dynamic behavior of the guest molecules.

The fabrication of single-crystal dendritic ZnO nanostructures via the vapor-phase transport method with Cu as catalyst at 930 degree Celsius is described. The ZnO dendrites with macroscopical appearance and nanomaterial properties could find potential use to develop effective and high performance gas sensors.

The low frequency noise of magnetic tunnel junctions (MTJs) annealed in a wide temperature range is examined in either in helium or hydrogen environments. The results have shown that the magnetic fluctuators in the MTJs have changed their frequency based on annealing field and temperature and the noise of the MTJs at low frequency is reduced by annealing in high magnetic field.

A photoelectrochemical model is presented for hydrogen production from water electrolysis using proton exchange membrane. Results suggest an increase in hydrogen production with an increase in temperature.

The thermodynamic properties of hydrogen gas in liquid water are examined by using Monte Carlo molecular simulation and the quasichemical theory of liquids. It is shown that the hydration free energy has resulted from a balance between chemical association and molecular packing, which is equally driven by unfavorable enthalpic and entropic components.

The concept of the molecular formula to understand molecular composition and structure of fundamental compounds from 19th century, based on non-mathematical logic to modern technique is reviewed.

The scaled hypersphere search method is employed to explain the structures and thermal behavior of the protonated water cluster, [H.sup.+][([H.sub.2]O).sub.8].

The commercial use and viability of the different complex hydrides that are used as onboard hydrogen carriers are discussed. Substances like alanates and borohydrides can also be easily used because of their rapid hydrogenation kinetics and the high mass percent of hydrogen present in them.

Biomass conversions, as well as various enzymatic methods are used to produce hydrogen by molecular photocatalysis from various neutral sources of carbon. Though the process is very useful for producing hydrogen, it cannot be widely used because of the energy wasted by the catalyst.

The thermodynamics of [H.sub.2] solution and hydride formation in a series of disordered Pd-Ag alloys is obtained by using both reaction calorimetry and equilibrium [P.sub.H2]-composition-T data. The enthalpies for hydride formation/decomposition are determined for alloys that have formed two phases, where the enthalpies for hydride formation has become more exothermic with [X.sub.Ag] while the corresponding entropy magnitudes are nearly constant.

A family of divalent metal adipate (adp) coordination polymers incorporating the kinked dipodal organodiimine 4,4'-dipyridylamine (dpa) obtained by hydrothermal synthesis are reported.

A consistent set of experimental thermochemical quantities for isomeric nitrophenols and nitrocresols were developed to derive reliable values for the enthalpy of formation of the nitrophenols at the reference temperature 298.15 K.

The investigation of monouranium and diuranium polyhydride molecules, U[H.sub.4][([H.sub.2]).sub.6] revealed a metal hydride with a large number of hydrogen atoms bound to uranium.

The analysis of the thermochemistry and trends in kinetic parameters for the hydrogen shift reactions from each carbon in n-butyl and n-pentyl peroxy radicals is presented.

The reactions of [O.sub.2] with products from OH to isobutene, 2-hydroxy-1,1-dimethyl, and 2-hydroxy-2-methylpropyl radicals were analyzed by ab initio and density functional calculations. The main products from the chemical activation reactions were those resulting from the Waddington mechanism, where an alkoxy radical was formed and subsequent [beta]-scission reaction results in strong [pi] bonds of carbonyl products.

The hyperthermal reactions, collision of ground state atomic oxygen [O([super 3]P)] with a liquid hydrocarbon squalane, were investigated using QM/MM direct dynamics. The results show that H abstraction is the most important process for all incident angles along with H elimination, double H abstraction, and C-C bond cleavage.

Quantum chemistry investigations are used to study the gas-phase chemistry active during the metal organic vapor-phase epitaxy (MOVPE) of GaN when Ga[(C[H.sub.3]).sub.3] and N[H.sub.3], diluted in a [H.sub.2] carrier gas, are used as precursors. The results have shown that the presence of [H.sub.2] as a carrier gas can enhance the rate of formation of gas-phase particles because it is a major source of atomic hydrogen, a promoter of gas-phase reactivity.

The thermodynamic cycle of hydrogen release and uptake for the chemical hydrogen storage compounds linked to borazane in the gas and condensed phases is analyzed using molecular orbital theory. The thermochemical calculations for dehydrogenation show that the exothermic nature of dehydrogenation decreases with an increase in the boron valency.

Alternative magnetic active charcoals (ACs) with magnetic responsibility for magnetic separations are synthesized by a chemical precipitation processing and subsequent heat treatments in [H.sub.2] or air atmosphere. It is shown that magnetic AC heat treated in [H.sub.2] has high ability for arsenic removal.

The effect of the hydrogen implantation on low temperature migration and gettering of impurities in Si is investigated. The results have shown that hydrogen implantation can be used for the impurity profile engineering and gettering studies in silicon in the low temperatures annealing regime.