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排序方式: 共有839条查询结果,搜索用时 15 毫秒
1.
H. Furuse N. Mori H. Kubo H. Momose M. Kondow 《Journal of Materials Science: Materials in Electronics》2007,18(1):81-85
We have measured optical transmittance through germanium in the mid-infrared region at room temperature using the Osaka free-electron laser (FEL). In spite of the fact that germanium is transparent in the mid-infrared region, we observed strong suppression of optical transmission under high-intensity FEL excitation. We found that the observed suppression is due to optical absorption in germanium. To analyze the experimental results, we have calculated optical transmittance of germanium within Keldysh theory 相似文献
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Hitoshi Kurokawa Taku Nakayama Yasunori Kobayashi Ken Suzuki Mutsumi Takahashi Seiichi Takami Momoji Kubo Naotsugu Itoh Parasuraman Selvam Akira Miyamoto 《Catalysis Today》2003,82(1-4):233-240
A modified Monte Carlo (MC) simulation was performed to investigate the hydrogen absorption behavior in Pd and Pd–Ag alloys of the composition PdxAg1−x (x=0.7–0.8) under H2 pressure (0.1 MPa) at different temperatures. The present method employed can consider the dissociative adsorption of hydrogen molecule and the subsequent absorption of hydrogen atom by formalizing the relationship between the pressure of hydrogen molecule and hydrogen atom. The potential parameters were determined to reproduce the solution enthalpy of hydrogen in pure metals. The results are in good agreement with experimental findings as well as previous theoretical studies. We confirmed that our method is useful to simulate the absorption of hydrogen in metals and alloys. 相似文献
4.
Anju Sawada Takehiro Kubo Yosikazu Abe Kazuyuki Matsumoto 《Journal of Low Temperature Physics》1995,101(3-4):707-712
The isochoric pressure of bcc Solid3He in the vicinity of the triple point has been measured by changing the temperature stepwisely and waiting for thermal equilibrium. We observed anomalous pressure kinks of the temperature dependence in the paramagnetic region near the triple point. This anomaly appeared at 0.37 to 0.40 tesla, and disappeared below 0.36 tesla. Moreover, critical phenomena at the transition point from the paramagnetic phase (PP) to the high field phase was observed and the phase line curves toward the PP side. 相似文献
5.
These days, the number of pharmaceutical patent applications which do not specify the principal active ingredient in the form of a chemical name or structure is increasing. These patents are difficult to retrieve in retrospective on-line searches using chemical structures or keywords. Furthermore, even if you could find them, the situation with regard to patentability is obscure and this causes considerable problems for the experts in charge of the patent search. If you are a searcher for a large pharmaceutical company, you might already be apprehensive of infringing such patents. We, the JFA,* gathered these patents together and studied the differences between their patentability in Japan, the US and the EPO. 相似文献
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W. Kasparek H. Idei S. Kubo T. Notake 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(4):451-472
An in-situ alignment system for beam waveguides based on an interferometric direction-finding antenna was investigated numerically and experimentally. The system consists of a reflector with four off-central positioned waveguide couplers in two directions. By nulling the difference of the power signals as well as the mixing signal from each coupler pair, spatial and angular alignments of a beam impinging on the mirror can be performed. In this paper, the characteristics of such a mirror are presented, and the design of a prototype intended for use in an ECH transmission line at LHD is described. Low-power as well as high-power tests at a frequency of 82.7 GHz were carried out, and the results are discussed. The device shows a high performance in agreement with theory. 相似文献
9.
Anacardic acids, 6-pentadec(en)ylsalicylic acids isolated from the cashew Anacardium occidentale L. (Anacardiaceae) nut and apple, were found to possess preventive antioxidant activity while salicylic acid did not show this activity. These anacardic acids prevent generation of superoxide radicals by inhibiting xanthine oxidase (EC 1.1.3.22, Grade IV) without radical-scavenging activity. Notably, the inhibition kinetics of anacardic acids do not follow hyperbolic dependence of enzyme inhibition on inhibitor contents (Michaelis–Menten equation) but follow the Hill equation instead. Anacardic acid (C15:1) inhibited the soybean lipoxygenase-1 (EC 1.13.11.12, Type 1) catalyzed oxidation of linoleic acid with an IC50 of 6.8 μM. The inhibition is a slow and reversible reaction without residual enzyme activity. The inhibition kinetics indicate that anacardic acid (C15:1) is a competitive inhibitor and the inhibition constant, KI, was 2.8 μM. Anacardic acids act as antioxidants in a variety ways, including inhibition of various prooxidant enzymes involved in the production of the reactive oxygen species and chelate divalent metal ions such as Fe2+ or Cu2+, but do not quench reactive oxygen species. The C15-alkenyl side chain is largely associated with the activity. 相似文献
10.
H Hanaue K Kanno M Mukai H Kubo K Tobita H Nakasaki T Tajima T Mitomi R Endo 《Canadian Metallurgical Quarterly》1993,18(1-2):1-4
Increased monoamine metabolism in experimental herpes simplex virus (HSV) encephalitis is well established. Both serotonin (5-HT) and dopamine (DA) systems are affected. HSV invades the raphe nuclei after its entry into the brain stem. However, no studies have been published concerning influences of HSV on the neurotransmitters in the raphe. In the present study, concentrations of 5-HT and DA and their metabolites in the raphe nuclei and related brain regions in rabbits with fulminant HSV encephalitis have been analyzed using high-pressure liquid chromatography. Encephalitis was induced by corneal inoculation with HSV. Homovanillic acid (HVA) and dihydroxyphenyl acetic acid (DOPAC) concentrations and HVA/DA ratios were increased in the raphe nuclei suggesting increased DA turnover. The most substantial changes were bilaterally decreased 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) concentrations in the raphe nuclei. The decrease in the raphe 5-HT was reflected also to the projection areas in the hemispheres, where 5-HT concentrations were lower in HSV-inoculated rabbits than in controls. The changes strongly suggest a direct influence of HSV on serotoninergic neurons. Since the ventral parts of the limbic system have rich serotoninergic afferents from the raphe, this also suggests that HSV may reach hemispheres in HSV encephalitis from the brain stem via the ascending serotoninergic system. 相似文献