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排序方式: 共有608条查询结果,搜索用时 15 毫秒
61.
Ishiwata H Abe Y Kubota H Kawasaki Y Takeda Y Maitani T Nishijima M Fukasawa Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(1):49-56
The mean concentrations and daily intake of four antifungal agents were estimated based on the results of an analysis of 7,005 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of diphenyl was 0.0004% of the allowable limit, and those of imazalil, o-phenylphenol, and thiabendazole were 14.0%, 3.5%, and 5.7%, respectively. The daily intakes of these antifungal agents per person, estimated from their concentrations and the daily consumption of the foods, were 0.000326, 1.89, 11.5, and 23.3 micrograms, respectively, and assuming a body weight of 50 kg, the amounts of these antifungal agents consumed were 0.000013%, 0.15%, 0.12%, and 0.47% of the acceptable daily intake, respectively. These values are similar to the values obtained on the basis of the results of the official inspection in fiscal years 1994 and 1996, except that the amount of diphenyl is much lower (1/100). 相似文献
62.
Ken-ichi Kurobe Takashi Fuyuki Hiroyuki Matsunami 《Solar Energy Materials & Solar Cells》2001,66(1-4)
High growth-rate Si epitaxy by plasma-enhanced chemical vapor deposition (PECVD) has been investigated for a thin-film solar cell application. A high growth rate of 50 μm/h was obtained at 1050°C with plasma which is 50% larger than that by the conventional CVD without plasma. The electrical properties are almost the same for epitaxial layers with and without plasma. For undoped n-type layers, the Hall mobility and carrier density were about 600 cm2/V s and low 1015 cm−3, respectively. The electron diffusion length in doped p-type layers was about 20 μm. These electrical properties for the layer with plasma, in spite of higher growth rate, are comparable or better than those without plasma. 相似文献
63.
Yong-Jin Pu Makoto Yoshizaki Takahiro Akiniwa Ken-ichi Nakayama Junji Kido 《Organic Electronics》2009,10(5):877-882
3,5-Dipyrenylpyridine (PY1) and 2,6-dipyrenylpyridine (PY2) were synthesized to achieve not only efficient electron injection from cathode but also high electron mobility. The both of compounds showed much higher electron mobilities than that of Alq3, and have a similar ionization potential and electron affinity. However, the barrier height of electron injection from cathode to PY1 in an organic light emitting device was much smaller than that to PY2, probably due to the steric hindrance to the central pyridine group. These results suggest that the chemical affinity of electron-transporting materials with cathode is more important than their own electron affinity to improve the electron injection. 相似文献
64.
Hiroshi Shimizu Keigo Miura Suteaki Shioya Ken-ichi Suga 《Journal of Process Control》1996,6(6):373-378
The physiological states with respect to cell growth and ethanol production in a yeast fed-batch culture can be recognized on-line by fuzzy inferencing. The error vector is newly defined in a macroscopic elemental balance equation and utilized for the on-line recognition of the physiological state of the micro-organisms. Fuzzy membership functions are constructed from the error vectors and state recognition is performed successfully by fuzzy inferencing. In particular, a usual physiological state for yeast cultivation in which aerobic ethanol production is accompanied by very low cell growth can be recognized accurately. 相似文献
65.
66.
Shock compaction experiments for diamond powder with an initial size of 2 to 4 μm, respectively. The difference in the mechanical properties of SiC and diamond improves the densification, and Si is available to join diamond particles via chemical reaction. The difference of the constituent particle radii, however, causes serious problems with the distribution of shock energy. 相似文献
67.
Natural circulation characteristics of a marine reactor in rolling motion and heat transfer in the core 总被引:5,自引:0,他引:5
A series of single-phase natural circulation tests in a model reactor with rolling motion was performed in order to investigate effects of the rolling motion on its thermal-hydraulic behavior. The loop flow rate in each leg changes cyclically with the rolling angle due to the inertial force of the rolling motion. As the rolling period becomes shorter, the amplitude of the loop flow rate oscillations becomes larger, and the phase lag between the rolling angle and loop flow rate oscillations becomes larger. On the other hand, the core flow rate does not oscillate, though its value changes with the rolling period. Its change correlates well with both the Reynolds number for rolling motion and the Rayleigh number, and it is considered to be caused by the change of the thermal driving head and the pressure loss through the loop. In order to simulate core flow rate change with the rolling period, a simple one-dimensional analytical model was proposed, and its verification was demonstrated. Heat transfer in the core is enhanced by the rolling motion and the enhancement is thought to be caused by the internal flow due to the rolling motion. Heat transfer coefficient in the core is well correlated with the Richardson number for rolling motion and is classified into three regimes. 相似文献
68.
K Nishijima M Kohyama T Hisatsune H Kato M Kakehi S Kaminogawa 《Canadian Metallurgical Quarterly》1997,61(7):1156-1162
alpha s1-Casein-specific CD8+ T cell clones expressed the interleukin (IL)-4 receptor, although they did not secrete detectable IL-4. We found that IL-4 significantly enhanced the secretion of interferon (IFN)-gamma by these CD8+ T cell clones. IL-4 also enhanced the secretion of IFN-gamma induced by stimulating the immobilized anti-CD3 antibodies of polyclonal CD8+ T cells which had been isolated from lymph nodes and were stimulated in vitro with the immobilized anti-CD3 antibody and IL-2. In addition, IL-4 added at the time of this first in vitro stimulation induced strong IFN-gamma productivity, as well as IL-4 and IL-10 productivity, which were detectable upon restimulation of these cells. Results are discussed in relation to the inhibitory effects of IFN-gamma production on IL-4-producing cells. 相似文献
69.
Atsuko Takita Katsuhiko Sasaki Ken-ichi Ohguchi 《Journal of Electronic Materials》2014,43(7):2530-2539
For the design of high-density electronic packages, finite element method (FEM) analyses to evaluate strength reliabilities of solder joints should be conducted by employing the material parameters which can precisely reflect the creep properties of solder joints in actual electronic equipment. To obtain accurate results of the structural analyses of the solder joints, a method to evaluate the steady-state creep deformation in situ must be developed. The indentation creep test is an effective method to evaluate the creep properties of the solder joints in situ; however, the creep properties obtained by this method do not give the same results as those obtained by tensile creep tests using bulk specimens. In this paper, the indentation creep test at 1 N loading for 9,000 s duration was experimentally conducted to confirm that the steady-state creep deformation obtained by the indentation creep test did not coincide with that by the tensile creep tests using bulk specimens. To identify the reason, the indentation creep simulation was conducted by FEM analysis. As a result, it was found that the reference area used to obtain the creep strain from the indentation creep test should be modified. A method to obtain the new reference area is proposed from comparisons of experiments with simulations. Finally, this paper shows that the creep properties obtained by the indentation creep test using the new reference area coincided with those obtained by tensile creep tests using bulk specimens. 相似文献
70.
Ryoma UegakiYoko Akiyama Sachiko TojoYoshihide Honda Shigehiro Nishijima 《Journal of power sources》2011,196(23):9856-9861
The degradation mechanism induced by radicals was investigated for Nafion®-117 by solution analysis. Nafion® was exposed independently to three kinds of radicals, OH, H and O2− which were produced separately by γ-irradiation. Based on the eluted elements, the scission site in the membrane was analyzed. The results showed that the scission site was classified into two and these locations were closely relating to oxidative and reductive reactions. The decreasing rate of proton conductivity was more significant under the influence of reductive radicals. The progression of the unzipping reaction of main chain was suggested to be initiated by the production of tertiary carbon radical by reductive radicals such as H and O2− with the aid of OH. The structural degradation such as collapse of cluster and the cluster decomposition as well as the performance degradation was found to be initiated by such reductive radicals. 相似文献