We synthesized new composite particles for hydrogen storage on the basis of an idea of “particle designing”. As starting materials, powders of Mg and YNi2 were selected. Fine composite particles containing mainly Mg2Ni could be designed by repetitive hydriding and dehydriding cycles at 673 K. In the synthesis process of the composite particles, the following two points were found to be essential for this technique. The first point is that, after being activated by the sequential processes of hydrogenation, amorphization and disproportionation, YNi2 reacts effectively with Mg. The second point is that evaporated Mg, which occurs during dehydriding, adheres to the surface of the activated YNi2 and accelerates a diffusion reaction to form Mg2Ni at the interface. In these composite particles, Mg2NiH4 is formed, even at 373 K, under a hydrogen pressure of 5 MPa. 相似文献
The surface chemical states of the perovskite-type compounds, strontium doped lanthanum cobalt oxides (La1?xSrxCoO3), have been investigated using X-ray photoelectron spectroscopy (XPS). Catalytic oxidations of both methane and CO have also been investigated using flow methods. The chemical composition of the surface of La1?xSrxCoO3 was very different from that in the bulk, which was measured by X-ray fluorescence spectroscopy (XRFS). The catalytic activity of La1?xSrxCoO3 increased with an increase in the quantity of cobalt atoms on the surface. 相似文献
The demand for energy in Japan is expected to increase steadily into the future, and it seems that the importance of nuclear power generation will be heightened more when the situation of our country which is not rich in energy resources is taken into account.
Furthermore, when we consider the present situation that the light water reactors have become common, recent outlook for the supply and demand for uranium resources, trends in the development of the fast breeder reactor technology, etc., the light water reactors are expected to remain dominant in the nuclear power generation of our country until at least the second half of the 21st century.
Based on such a background five PWR utilities in Japan (Hokkaido, Kansai, Shikoku, Kyushu, and the Japan Atomic Power), and Mitsubishi Heavy Industries, Ltd. have jointly started researching the Next Generation PWR which is expected to be the leading nuclear power plant taking place of APWR. 相似文献
The permeation and separation characteristics of aqueous polymer solutions using acrylonitrile-styrene copolymer membranes were investigated under various conditions. The membranes obtained from dimethyl sulfoxide solution of acrylonitrile-styrene copolymer have not a sufficient reproducibility and stability of permeation. These lacks were improved by adding ethylene glycol or glycerol to the casting solution and treating the membranes with pressure. The permeation and separation characteristics were influenced significantly by the additional amount of above additives, the heat treatment temperature, and the operating pressure. It was found that the concentration polarization of poly(vinyl alcohol) molecules onto the surface of the acrylonitrile-styrene copolymer membranes is smaller than that onto hydrophilic polymer membranes such as membranes of cellulose acetate, cellulose nitrate, and nylon 12, etc. Moreover, the acrylonitrile-styrene copolymer membranes show better performance for separation and concentrating of aqueous polymer solutions than hydrophilic membranes. 相似文献
The adsorption properties of oxygen and methane on Ga-ZSM-5 and Cu-ZSM-5 catalysts were examined by a TPD method to clarify the extraordinary selectivity of HC-SCR using methane on Ga-ZSM-5. It was observed that Ga-ZSM-5 did not adsorb oxygen but adsorbed methane dissociatively, while on Cu-ZSM-5 oxygen was dissociatively adsorbed and reacted with adsorbed ethylene. 相似文献
Summary The permeation and separation characteristics of methanol/n-pentanol systems and n-propanol/n-heptane systems through nylon 12 membranes were studied by changing the feed composition of the binary organic mixtures. These characteristics were discussed from the viewpoints of physical and chemical nature of the permeating molecules and the membrane. 相似文献
Polyarylates from substituted hydroquinones (HQs) and p-terphenyl-4,4″-dicarboxylic acid (TPDA) that were modified with 1,2-bis(phenoxy)ethane-4,4′-dicarboxylic acid (PEC), 1,2-bis(2-chlorophenoxy)ethane-4,4′-dicarboxylic acid (ClPEC), terephthalic acid (TA) and p-hydroxybenzoic acid (HBA) were prepared and their thermal and mechanical properties were investigated. These polyarylates exhibited liquid crystallinity at about the same temperatures as polyarylates derived from substituted HQs and 4,4′-diphenyldicarboxylic acid (BB). However, as-spun fibers and injection-molded specimens of these polyarylates exhibited lower moduli than those of substituted HQs and BB that were modified with PEC, Cl-PEC and TA. 相似文献