著者

前田 治男 五十嵐 雅之 宮川 喜洋 小林 肇 佐藤 光三 眞弓 大介 坂田 将

出版者

石油技術協会

雑誌

石油技術協会誌 (ISSN:03709868)

巻号頁・発行日

vol.76, no.6, pp.530-537, 2011 (Released:2014-01-18)

参考文献数

7

被引用文献数

1 2

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INPEX Corporation, Tokyo University and Natural Institute of Advanced Industrial Science and Technology (AIST) have been working since 2008 to study methane-producing technology using microbes inhabiting depleted oil and gas fifields. The concept and mechanism of microbial methane conversion are depicted as follows. First, inhabiting bacteria prompt to produce acetic acid or hydrogen from residual petroleum components in the underground reservoir. Next, methane-producing microbes (methanogens) are concerned in generating methane from the produced acetic acid, hydrogen and carbon dioxide injected for geological sequestration as CCS operation.A wide variety of hydrogen- and methane-producing microbes have been discovered in (depleted) oil fields. We found that microbes indigenous to the reservoir brine could produce methane probably by using crude oil as a carbon source in the presence of CO2 (10 mol%).Kinetics of gas (methane, carbon dioxide) production and consumption of acetic acid indicated that there are two reaction pathways from oil to methane; the acetoclastic methane producing pathway and the hydrogentrophic methane producing pathway.Furthermore, from the result of methane producing experiments and Carbon isotope tracer test, the existence of syntrophic cooperation between hydrogen producing bacteria and methane producing archaea is also identified.We are currently evaluating the way to enhance the capability of methane-producing microbes and developing an effective and efficient process for methane production in the actual reservoir condition.Our results will lead to establish a new MEOR system that converts residual oil in depleted oil fields into environmentally friendly methane efficiently.

著者

合田 隆 佐藤 光三

出版者

石油技術協会

雑誌

石油技術協会誌 (ISSN:03709868)

巻号頁・発行日

vol.76, no.3, pp.233-243, 2011 (Released:2014-01-18)

参考文献数

21

被引用文献数

3

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This study aims at developing a new population-based global optimization algorithm, called iterative Latin hypercube samplings (ILHS), and applying the ILHS to a global optimization of well placement for geological storage of CO2. The ILHS utilizes a space-filling property specific to the Latin hypercube sampling (LHS) : each independent variable xj(j=1, …, d) is divided into n strata of equal marginal probability and sampled once from each stratum. In the ILHS, the LHS is generated iteratively while a cumulative distribution function for each variable at the current step is updated from the fitnesses evaluated at the previous step. This iterative process enables us to search a global optimum in a derivativefree way. Considering a global minimization of an objective function involving only continuous independent variables, the mathematical formulation of the basic algorithm is described first.In general, in order to carry out a numerical simulation of CO2 migration in the subsurface, the target domain is divided into multiple grids and the well placement is indicated by the grid index. Therefore, we need to consider a global optimization of an objective function involving discrete independent variables. Here, a brief handling method toward the application of the ILHS involving discrete independent variables is introduced and we attempt to find an optimal well placement using the ILHS so as to minimize the amount of mobile CO2. The results for example problems confirm that our proposed algorithm can search an optimal solution effectively within a practical number of simulation runs.

著者

皆川 洋至 井樋 栄二 佐藤 毅 今野 則和 本郷 道生 佐藤 光三

出版者

日本肩関節学会

雑誌

肩関節 (ISSN:09104461)

巻号頁・発行日

vol.20, no.1, pp.103-109, 1996-10-15 (Released:2012-11-20)

参考文献数

14

被引用文献数

3

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Each muscle of the rotator cuff is known to have several intramuscular tendons which provide attachment to numerous muscle fiders. The anatomical relationship between intramuscular and extramuscular tendons needs to be determined to know the distribution of the force to the rotator cuff tendon. The purpose of this study was to clarify the morphology of the transitional zone of intramuscular to extramuscular tendons of the rotator cuff.The muscle fibers of cuff muscles of 20 embalmed shoulders without full-thickness rotator cuff tears were removed to examine the transitional zone of the intramuscular to extramuscular tendons macroscopically. Histological sections of the musculotendinous junction were perpared to evaluate the transitional forms microscopically.We defined the intramuscular tendon as the tendon inside the muscle belly and the extramuscular tendon as the tendon outside the muscle. The extramuscular tendons from the rotator cuff tendon distally. Location was expressed as the % position of the anterior and posterior margins of the musculotendinous junction. The intramuscular tendons of the infraspinatus, teres minor, and subscapularis were contiguous to the whole extramuscular tendons and that the supraspinatus was located in the anterior one-third of the extramuscular tendon(0±0% to 28±15%). Microscopically, the intramuscular tendon of the supraspinatus formed a tendon fiber bundle and was continuous with the second of five layers of the extramuscular tendon (Clark and Harryman,1992).Conclusion: The connection of intramuscular tendon to extramuscular tendon was specific to each cuff muscle. The intramuscular tendon of the supraspinatus was attached to the anterior one-third of the extramuscular tendon and was contiguous to the second layer.