Abstract: There is provided a metal-bonded grinding stone including an abrasive grain layer in which a plurality of abrasive grains and a plurality of pores are dispersed in a metal bonding material, in which a porosity of the plurality of pores in the abrasive grain layer is 40% or more and 99% or less.

Abstract: An alloy of the composition represented by the formula, Mm.sub.1-x Ca.sub.x Ni.sub.5-y A.sub.y, wherein Mm stands for Mischmetal, A for one member selected from the group consisting of Al, Co, Cr, Fe, Mn, Si and Zn, x for a number within the range of 0.01 to 0.99 and y for a number within the range of 0.05 to 3 is useful for storage of hydrogen.

Abstract: An alloy having a composition of the general formula, MmNi.sub.5-x A.sub.x-y B.sub.y, wherein Mm is misch metal, A is one member selected from the group consisting of Al, Cu, and Mn and B is one member selected from the group consisting of Al, Co, Cu, Fe, Mn, and Si, providing that both A and B do not represent one same compound, is useful for the occlusion of hydrogen.

Abstract: A Mischmetal alloy of the general formula: MmNi.sub.5-x Cr.sub.x-y A.sub.y, wherein Mm stands for Mischmetal and A for Al, Co, Cu, Fe, Mn or Si, is highly useful as an alloy for the storage of hydrogen by occlusion.

Abstract: A device for the storage of hydrogen, comprising a container, two porous plates opposed parallelly to each other across a fixed distance and fastened to the inner wall of the container, heating/cooling members disposed one each outside the porous plates and separated by a fixed distance from the corresponding porous plates, and an alloy capable of storing hydrogen placed in the spaces formed between the porous plates and the heating/cooling members.

Abstract: An alloy of the general formula, MmNi.sub.5-x A.sub.x (wherein, Mm stands for misch metal, A for one member selected from the group consisting of B, Ca, Cr, Cu, Fe, V, Zn and Si, and x for a numerical value in the range of from 0.01 to 2), which is useful for the occlusion of hydrogen.

Abstract: An indium oxide (III) film produced by a method which comprises first forming a film of indium oxide (I) and subsequently oxidizing the film.

Abstract: An alloy comprising Mischmetal, cobalt and nickel is effectively usable for occlusion of hydrogen.

Abstract: A method for efficient production of hydrogen by thermochemical decomposition of water by use of tri-iron tetraoxide and hydrogen bromide as main cyclic reaction media.

Abstract: A method for the thermochemical production of hydrogen from water is disclosed in which barium iodide, carbon dioxide, ammonia and water are allowed to react with one another and give rise to barium carbonate and ammonium iodide, the ammonium iodide thus produced is thermally decomposed to produce hydrogen, iodine and ammonia, and the hydrogen thus produced is recovered as the product. The by-produced barium carbonate is allowed to react with the iodine remaining after the separation of hydrogen thereby to produce barium iodide, carbon dioxide and oxygen, and the barium iodide and carbon dioxide are recycled to the reaction system. The ammonia which remains after the separation of hydrogen is also recycled to the reaction system. By causing the by-products occurring in the various reactions to be recycled to the relevant reaction systems, hydrogen is efficiently produced from water at a reaction temperature of not more than 800.degree. C.