Journal of MMIJ
Online ISSN : 1884-0450
Print ISSN : 1881-6118
ISSN-L : 1881-6118
125 巻 , 2 号
選択された号の論文の5件中1~5を表示しています
論説
  • 古宇田 亮一
    2009 年 125 巻 2 号 p. 51-56
    発行日: 2009/02/25
    公開日: 2011/02/19
    ジャーナル フリー
    This paper summarizes the recent trend of world underground laboratories for the radioactive waste disposal. The research is now developing in the clay stone type, though they meet the difficulty of very low mobility or diffusivity of chemical components in the fluid in clay stone. In Mont Terri of Switzerland, the researches of fluid and clay stone are suggested to contribute to the public acceptance (PA) . It is also important to introduce the information management to disclose and exchange of research information with advanced information systems. The fluid and rock interaction research of clay stone can contribute to the carbon dioxide sequestration in underground, the pollution of soil and ground water, and sealing potential in hydrocarbon exploration that are recently important issues that we have to solve.
論文
  • 奈良 禎太, 米田 哲朗, 金子 勝比古
    2009 年 125 巻 2 号 p. 57-61
    発行日: 2009/02/25
    公開日: 2011/02/19
    ジャーナル フリー
    The effect of the humidity on subcritical crack growth in igneous rock in air was investigated experimentally. Rocks used in this study were Kumamoto andesite and Oshima granite. Double-Torsion method was used in this study to measure the crack velocity and the stress intensity factor. All experiments were conducted under the same temperature and different relative humidity to investigate the effect of the humidity.
    It was shown that the humidity affected the crack velocity strongly. The crack velocity increased with the increase of the humidity. The crack velocity increased by 1 ∼ 4 orders of magnitude when the humidity increased threefold or fourfold. This increase is larger than that estimated from the classical stress corrosion theory. It is concluded that the humidity has the strong effect on subcritical crack growth in rock and the control of the humidity is important to prevent the weakening of rock.
  • 久保山 宏, 中野 博昭, 大上 悟, 福島 久哲, 小林 繁夫
    2009 年 125 巻 2 号 p. 62-67
    発行日: 2009/02/25
    公開日: 2011/02/19
    ジャーナル フリー
    The effect of thiourea on copper electrodeposition has been investigated by measuring the cathodic polarization curves for aqueous H2SO4-CuSO4 solutions and observing the surface morphology of deposited Cu. The cathode potential for Cu deposition was depolarized by the addition of thiourea less than 0.1 mmol/L, whereas it was significantly polarized with increasing the concentration of thiourea above 0.1 mmol/L. The thiourea showed both effects of depolarization and polarization on Cu deposition depending on its concentration. The grain size of deposited Cu decreased monotonously by the addition of thiourea. In the presence of both thiourea and gelatin, the polarization effect due to gelatin decreased with addition of thiourea less than 0.1 mmol/L. The grain size of deposited Cu looks smaller in the presence of both thiourea and polymer additive such as gelatin or PEG than thiourea alone. On the other hand, in solution containing both thiourea and Cl- ions, the synergistic effect of thiourea and Cl- ions on the polarization for Cu deposition was observed only in the case that the concentration of thiourea was increased to 10 mmol/L. However, at 0.1 mmol/L of thiourea, the cathode potential was depolarized irrespective of coexistence of Cl- ions.
  • 田渕 祥之, 村上 進亮, 山冨 二郎
    2009 年 125 巻 2 号 p. 68-74
    発行日: 2009/02/25
    公開日: 2011/02/19
    ジャーナル フリー
    In order to establish more sound resource use strategies, it is essential to know the in-use stocks of minerals in Japan, which are potential future resources as urban mine, while they can also be future wastes. This research focuses on nickel. Nickel has broad application, such as stainless steel, plating, and electronic materials to cell, while we recently experience huge volatility in its price. Nickel flow from the cradle to the grave has not been examined for Japan.
    This paper captured the nickel flows throughout its lifecycle; from mining, refineries, manufacturing, consumption to recycle and final disposal. The purpose is to figure out in-depth nickel flow in Japan and examine it quantitatively. Nickel material flows were estimated with various references and we figured out the intermediate flows, consumptions, and fabrications. As for the downstream flows, since the direct observation of nickel flows is impossible and there are no data available, they were estimated with monetary flows described in input-output table. The category classification of the table was also utilized. Post consumption flows were estimated assuming Weibull survival function for the commodities. Finally the amount of the in-use stocks of nickel in Japan was estimated with the estimated historical flow data and analyzed.
  • 湯本 徹也, 白鳥 寿一
    2009 年 125 巻 2 号 p. 75-80
    発行日: 2009/02/25
    公開日: 2011/02/19
    ジャーナル フリー
    Although Cu, Ag, Au and other metals are used for the electrical and electronic equipment (EEE) , the many kinds of metals in WEEE (Waste EEE) are not recycled now except Cu and precious metals. It is desired to promote recycling of metals in WEEE. However, EEE is improved with a time and the components and their materials which are used for EEE also change. That is, it means that the quality of recycling resources changes in recycling of WEEE. In this paper, it aimed at creating those inventories as basic information on examination of the recycling system of WEEE. The change of the mobile phone unit by improvement such as a miniaturization and introduction of a new function is quicker than other EEE. Therefore, contents of each element in mobile phone's PCB (Printed Circuit Board) manufactured in 1997, 2002-2003 and 2005-2006 were investigated, and the causes of some changes were considered. It was shown that Pd's substitution material (Ni) and tantalum capacitor's substitute device (ceramic capacitor) have spread, and the amount of Pd and Ta used is decreasing by the unstable supply of metal resources or their rising value. It was shown that the amount of the harmful elements, such as Pb, Sb, Br, is decreasing by new substance regulation and growing environment-conscious. Moreover, some points in the recycling system which should be taken into consideration were clarified.
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