• Korean Journal of Materials Research
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• v.9 no.4
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• pp.386-391
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• 1999

The charge-discharge, the high-rate dischargeability, and the self discharge characteristics of the electrodes composed of rapidly solidified ZrV\ulcornerMn\ulcornerMo\ulcornerNi\ulcorneralloy, which has the form of partial substitution of Mn, Mo, Ni for V in $ZrV_2$ were studied. The alloys were prepared using Arc & RSP(Rapid Solidification Process) at the rotating roller speed of 2000 and 5000 rpm. Some of them were received heat treatment at$ 560 ^{\circ}C$ for 1 hour after the solidification to investigate the effect of the heat treatment. It was fond that cycle life was significantly improved by RSP, whereas discharge capacity, activation rte and high rate dischargeability were decreased compared with the conventional arc melting method. The capacity loss seems to be due to the loss of the crystallinity and the increase of the cycle life ascribed to the presence of the amporphous phase as well as the refined grain size of less than 0.2$\mu\textrm{m}$. Heat treatment of the alloy cooled at 2000 rpm improved the cycle life. In case of the alloys cooled at 5000 rpm, both the discharge capacity and the activation rate were significantly improved by the heat treatment.

• Transactions of the Korean hydrogen and new energy society
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• v.15 no.3
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• pp.220-227
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• 2004

The purpose of this paper is, based on the theoretical background of the principle of gas purification and absorption, and the absorbing ability of metals, to syudy the efficiency of gas purification of inorganic gases using Zr alloys, so as to contribute to the IT industry. To produce and distribute gas with high purity and ultra-high purity, different types of gas purifier are currently being used: distillation type, getter type, catalyst type, absorption at low-temperature type, and membrane separation equipment. From the different purification methods mentioned above, the getter type gas purifier is capable of not only high performance and capacity but also P.O.U(Point Of Use) method. The key of the getter type gas purifier is its efficiency of gas purification, which is the subject chosen for this study.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.6
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• pp.553-557
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• 2020

It is possible that hydrogen could replace coal and petroleum as the predominant energy source in the near future, but several challenges including cost, efficiency, and stability. Mg and Mg alloys are attractive hydrogen storage materials because of their lightweight and high absorption capacity. Their range of applications could be further extended if their hydrogenation properties could be improved. The main emphasis of this study was to investigate their hydrogenation properties for Synthesis of 10wt.% CaF2 in Mg2NiHx systems. The effect of BCR (66:1) and MA time (96 hours) on the hydrogenation properties of the composite was investigated. also, Mg2NiHx-10wt% CaF2 composites prepared by Mechanical Alloying are used in this work to illustrate the effect of catalysts on activation energy and kinetics of Magnesium hydride.

• Transactions of the Korean hydrogen and new energy society
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• v.9 no.1
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• pp.16-24
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• 1998

Recently Zr-based $AB_2$ type hydrogen absorbing alloy has received much attention as a negative electrode material for the Ni-MH batteries because of its high capacity. In this study $ZrV_{0.1}Mn_{0.7}Ni_{1.2}$ alloy was chosen and the effects of heat treatment and a partial substitution of the Mo in Mn site on the various electrode properties were investigated. The alloys was prepared by arc melting (as-cast sample). Some of them were heat treated at $1,100^{\circ}C$ for 4 hours. After this they were differentiated by the different cooling rates of slow cooling and quenching. Various electrode characteristics such as activation process, high rate dischargeability and self discharge characteristic were investigated with the three types of electrodes. It was found that heat treated alloys resulted in an increase in plateau flatness of P-C isotherms however both discharge capacity and high rate capability were decreased. And the partial substitution of Mo for Mn in $ZrV_{0.1}Mn_{0.7}Ni_{1.2}$ alloy improved the self-discharge characteristic without the loss of discharge capacity (300mAh/g).