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Mesoporous chromium( iii) terephthalate MIL-101 was treated with aqueous solutions of sodium fluoride, chloride, and bromide. The properties of the resulting compounds to sorb nitrogen, hydrogen, and methane were studied. The methane sorption was shown to depend on the nature of the inserted halide ion. The treatment with a sodium chloride solution leads to an increase in the methane uptake by MIL-101. [ABSTRACT FROM AUTHOR]

The equiatomic intermetallic compound TiFe has been prepared by elemental mechanochemical synthesis in a planetary ball mill from Fe and Ti powders. The structural and phase transformations during synthesis were followed using X-ray diffraction. The reaction of the synthesized compound with hydrogen was studied volumetrically. The results demonstrate that the hydrogen capacity of the mechanochemical TiFe is 1.2 wt % at 2.5 MPa. Its absorption isotherm has an extended plateau in the range 1.6-1.7 MPa at room temperature. [ABSTRACT FROM AUTHOR]

The interaction of mesoporous chromium( iii) terephthalate [Cr3O(C8H4O4)3F(H2O)2] (MIL-101) with an aqueous solution of the anionic cluster [Re4S4F12]4− ({Re4}) afforded a novel hybrid material {Re4}@MIL-101. According to the elemental analysis data, one cavity of the nanoporous framework contains up to two-three tetranuclear rhenium clusters. The hybrid sorbent obtained reversibly absorbs up to 3.7 wt.% hydrogen at 77 K and 30 atm. [ABSTRACT FROM AUTHOR]

Properties of magnesium hydride and multicomponent materials on its basis are considered in terms their use for reversible hydrogen storage. Special attention is given to methods of magnesium hydride production, including application of various catalysts and nonequilibrium high-energy processing. Principal advances in the optimization of magnesium hydride compositions for practical use are presented and possible lines of further works in this field are formulated. [ABSTRACT FROM AUTHOR]

Hydrogen adsorption isotherms of crystalline C60 were measured in the temperature interval from 223 to 573 K and under hydrogen pressure up to 2000 atm. Only the 573 K isotherm exhibited evidence for chemisorption starting from ∼800 atm. Hydrogen adsorption for isotherms measured below 473 K appeared to be not saturated even at 2000 atm. Maximum observed adsorption for these isotherms is almost the same and corresponds to 1.6–1.8 H2 molecules per C60. In contrast to experiments performed at lower pressure, presented data can not be explained only by adsorption of single H2 molecule in octahedral sites of C60 structure. [Copyright &y& Elsevier]

Radiation-induced absorption and lasing efficiency of a hermetically coated erbium-doped fiber saturated with molecular hydrogen are studied. It is shown that H2-loading of hermetically coated erbium-doped fibers prolongs their service time in space more than in 5 times, making such fibers promising for space applications. [ABSTRACT FROM AUTHOR]

The transition of the hexagonal ice phase Ih to the clathrate phase sII has been found in the H2O–H2 system at a pressure of about 1 kbar under conditions of an excess of gaseous hydrogen. The pressures of the Ih→sII and sII→Ih transitions have been determined over a temperature range from –36 to –18°C, and the pressure dependence of the synthesis temperature of the clathrate phase from a liquid at pressures from 1.0 to 1.8 kbar has been constructed. The solubility of hydrogen in the Ih and sII phases and in liquid water has been measured. The concentration of hydrogen in the clathrate phase sII is about 1.2 wt % (10 mol %) near the boundary of the sII→Ih transition, and it increases to 2 wt % (16 mol %) at a pressure of 1.8 kbar. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]