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排序方式: 共有253条查询结果,搜索用时 15 毫秒
161.
The degradation of alkylcyclohexane by Acinetobacter sp. ODDK71 was investigated. Strain ODDK71 degraded alkylcyclohexanes (alkyl side chain length of > or = 12) by co-metabolism when hexadecane was used as a growth substrate. GGMS analysis of co-metabolized products from dodecylcyclohexane suggests that strain ODDK71 degraded dodecylcyclohexane via a ring oxidation and an alkyl side chain oxidation pathways. The ring oxidation pathway of dodecylcyclohexane is a novel pathway of microbial degradation of dodecylcyclohexane. 相似文献
162.
Fumihiko Yoshiba 《国际能源研究杂志》2004,28(15):1361-1377
A temperature analysis model of a molten carbonate fuel cells (MCFC) stack is used to calculate the single electrode heat effects. The magnitude of heat which evolves from the cathode and absorbed at the anode is large, and in similar value to the electrical output of a MCFC. This suggests that the heat evolution of a single electrode causes a temperature difference between the electrodes. The temperature distribution in the electrolyte plate is evaluated to establish more accurate results concerning the temperature analysis model of the stack. The temperature distribution in the electrolyte plate is studied by applying irreversible thermodynamics. When the operating current density is less than 3000 A m?2 and the thermal conductivity of the electrolyte is more than 2 W m?1 K?1, the temperature difference between cathode and anode is estimated to be less than approximately 1 K. This result proves that the temperature difference between the electrodes can be supposed constant in constructing the temperature analysis model of the MCFC stack. This results also allows us to construct a two‐dimensional heat production distribution in the cell plane and discrete heat production distribution in the stacking direction for the practical use of the temperature analysis model. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
163.
T Yamamoto K Moji Y Kusano K Kurokawa K Kawagoe S Katamine 《Canadian Metallurgical Quarterly》1998,25(10):516-521
BACKGROUND AND OBJECTIVES: Chlamydia trachomatis infection is believed to be the most common bacterial sexually transmitted disease (STD) in industrialized countries. The objective of the current study was to assess the recent trend in the prevalence of C. trachomatis in Japan. GOAL OF THIS STUDY: To determine the trend in the seroprevalence for C. trachomatis among pregnant women in Nagasaki, Japan, during the past 10 years. STUDY DESIGN: The seroprevalence for C. trachomatis of 9,652 pregnant women of various ages screened in 1996 and 1997 was compared with those of 275 and 297 stocked samples from 1987 and 1992, respectively. Serum antibodies to C. trachomatis were detected by the enzyme immunoassay. Prospective samples of 33 seropositive cases were also analyzed to determine kinetics of the serum antibody titer. RESULTS: The seroprevalence has decreased in all age groups during the last 10 years. More than 70% of seropositive cases converted to be seronegative within 10 years. CONCLUSION: The prevalence of C. trachomatis has been decreasing among Japanese pregnant women. 相似文献
164.
H Miyake Y Hori H Takeoka M Takuma T Kawagoe H Mori 《Canadian Metallurgical Quarterly》1998,171(2):387-392
OBJECTIVE: The purpose of this report is to present the characteristic features on chest radiography and CT of systemic arterial supply to normal basal segments of the left lung in three cases. CONCLUSION: Accurate interpretation of chest radiographs and CT scans is important in making the correct diagnosis and avoiding life-threatening lung biopsy. 相似文献
165.
Y Nakamura K Kawagoe T Obi A Miyamoto S Ishiguro A Nishio 《Canadian Metallurgical Quarterly》1998,21(4):304-308
The ideal pleural sclerosing agent should be easily administered, without significant side effects, inexpensive, and widely available. None of the agents presently used meets all of these criteria. Ethanolamine oleate (ETH) is a sclerosing agent used in the sclerotherapy treatment of varicose veins of the legs and esophagus. The objective of the present study was to assess the efficacy of ETH as a pleural sclerosant in rabbits. An additional objective was to assess if better results were obtained when dextrose 50% (D50) as opposed to saline was used as the diluent. Each group of 10 rabbits received a total volume of 2 ml intrapleurally. The eight treatments were as follows: (1) 2 ml saline; (2) 2 ml D50; (3) 25 mg ETH plus 1.5 ml saline; (4) 25 mg ETH plus 1.5 ml D50; (5) 50 mg ETH plus 1.0 ml saline; (6) 50 mg ETH plus 1 ml D50; (7) 75 mg ETH plus 0.5 ml D50, and (8) 100 mg ETH. The rabbits were sacrificed 28 days after the injection. The intrapleural instillation of ETH resulted in evident pleurodesis, which was dose-dependent; 100 mg ETH induced significantly (p<0.05) more adhesions than did any other treatment. The selection of the diluent had no effect on the pleurodesis. The microscopic examination of the right visceral pleura showed that the mean degree of fibrosis after 100 mg ETH was significantly (p<0.05) greater than that after the other solutions. The mean degree of pleural inflammation, lung inflammation and lung fibrosis was minimal in all the groups. From this study we conclude that undiluted ETH produces pleurodesis in our experimental model. At the doses used, the pleurodesis was less than that produced after talc, tetracycline derivatives or silver nitrate in the same model. 相似文献
166.
The enzyme-catalyzed production of lactosucrose in a simulated moving-bed reactor is investigated. A numerical model is derived and verified by data obtained from simulated moving-bed reactor experiments. Based on the derived model, parameter studies and optimization are carried out. It is found that along with the flow rate settings, substrate feed and enzyme concentration and thermal deactivation of enzyme strongly influenced the product yield. Simulation showed that despite of parallel and consecutive side reaction, the maximum lactosucrose yield can reach 69%, which represents a yield increase of 36% relative to the equilibrium yield. 相似文献
167.
The silver chelate of 2-(4-thiazolyl)benzimidazole was exchanged for the interlayer cation of Li-taeniolite and Na-montmorillonite. The structure of the resulting films was derived from the (00l) relative intensities observed by X-ray diffraction. Four arrangements of the chelate between the silicate layers were considered, and the projected area of the chelate for each orientation was calculated. In Li-taeniolite the projected area available for one positive charge was too small to allow full exchange of the interlayer lithium cations by the silver chelate. On the other hand, the sodium ions in montmorillonite could readily exchange with the bulky silver chelate. Structural model calculation on the resulting clay film indicated that the silver chelate was oriented vertically between the layers of montmorillonite with its extremities at the center of linked the ditrigonal cavities. 相似文献
168.
169.
Fumihiko Yoshino Masaichi-Chang-il Lee Kyo Kobayashi Yuki Hayashi Okezie I. Aruoma 《Journal of Functional Foods》2009,1(4):375-380
Oxidative and nitrosative stress mechanisms are widely implicated in the biological and pathological processes involved in aging, cardiovascular and neurodegenerative diseases. Although this has continued to fuel suggestions of the benefits of antioxidant functional foods, in vivo methods for assessing the integrity of this remain limited. A novel electron spin resonance (ESR) technique for evaluating oxidative stress and location of its damage in the brain of spontaneously hypertensive rats (SHR) has been described [Lee, M.-C., et al. (2004). Assessment of oxidative stress in the SHR brain using electron spin resonance (ESR) imaging and in vivo L-Band ESR. Hypertension Research, 27, 485–492]. The reconstructed 2D ESR images of the distribution of a blood brain barrier-permeable nitroxyl spin probe, 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (MC-PROXYL) was used to investigate the ability of fermented papaya preparation (FPP, a product of yeast fermentation of Carica papaya Linn.) to modulate oxidative stress of SHR brain. Supplementation (5–7 months) with FPP (50 mg/rat/day) significantly increased the decay of the ESR images of the MC-PROXYL, suggesting that FPP may have up-regulated the redox defense activity in the SHR brain. Herein is an in vivo noninvasive technique for the study of oxidative stress and its modulation by dietary factors (that may be intended for applications as neuroprotectants in chronic degenerative disease involving loss of brain function). 相似文献
170.
The paper is based on a review of research on media selection and related topics on the one hand and on an explorative pilot
survey on the other. In summarising the review, the authors propose that the factors explaining media choice be grouped into
five categories: (1) the properties of the media itself affect its choice, (2) properties of the user affect media choice,
(3) the communication situation plays an important role, (4) macro factors explain media choice, and (5) media choice can
be explained as the outcome of a dynamic multiparty negotiation process. The pilot survey compares Japanese and Finnish students’
preference of media in various communication situations. The survey results encourage reserving, local macro factors or culture,
a certain amount of explanatory force in explaining media choice. 相似文献