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排序方式: 共有1616条查询结果,搜索用时 0 毫秒
981.
Yutaka Ota 《Electrical Engineering in Japan》2019,207(4):3-7
Sales of electric vehicle are rapidly growing worldwide. Vehicle grid integration is important for mitigating impact of charging demand on the distribution feeders, realizing renewable powered charging from the rooftop photovoltaic and wind power generation, and contributing to the Vehicle‐to‐Grid ancillary services for the power systems. This article reviews current trends of the vehicle grid integration R&D. Future prospective is also pointed out on the key issues such as an electrical interface, multiple services integration, and the electric vehicle living demonstration for open innovation. 相似文献
982.
Serum sulfatide abnormality is associated with increased oxidative stress in hemodialysis patients 下载免费PDF全文
Huang Yuzhe Yuji Kamijo Koji Hashimoto Makoto Harada Taro Kanno Eiko Sugiyama Mamoru Kyogashima Tomomasa Oguchi Takero Nakajima Yutaka Kanno Toshifumi Aoyama 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(3):429-438
Sulfatides are major glycosphingolipids of lipoproteins that influence atherosclerosis and blood coagulation. Our previous cross‐sectional study of hemodialysis patients showed that serum sulfatide levels decreased markedly with increasing duration of hemodialysis treatment, which may contribute to the development of cardiovascular disease. However, this past study could not demonstrate the time‐dependent change in serum sulfatide levels in each patient, and the underlying mechanism is unknown. To confirm the time‐dependent aggravation of serum sulfatide abnormality, 95 stable hemodialysis outpatients were followed up for 3 years. To show the underlying mechanisms, we statistically analyzed correlations between serum sulfatide levels and clinical factors, including an oxidative stress marker, malondialdehyde. Serum sulfatides were quantified by mass spectrometry after conversion to lysosulfatides. Malondialdehyde was measured using a colorimetric assay. The results showed a time‐dependent decrease in serum sulfatide levels associated with increased malondialdehyde levels, although the absolute level of serum malondialdehyde does not determine the baseline level of serum sulfatides. Multiple linear regression analysis showed a significant correlation only between the time‐dependent change in serum sulfatide levels and the time‐dependent change in serum malondialdehyde levels. This study demonstrated, for the first time, a time‐dependent aggravation of serum sulfatide abnormality in hemodialysis patients, as well as the potential relationship between serum sulfatide abnormality and increasing oxidative stress. These findings suggest that oxidative stress might be an aggravating factor in serum sulfatide abnormality. As continuation of hemodialysis treatment hardly improves abnormal serum sulfatide levels or increased oxidative stress, development of novel therapeutic strategies may be important. 相似文献
983.
Suzuki S Taketani H Kusumoto K Kashiwagi Y 《Journal of Bioscience and Bioengineering》2006,102(6):572-574
High-throughput genotyping of Aspergillus oryzae was achieved using an FTA card for the extraction of a genomic DNA template for polymerase chain reaction from a fungal colony growing on an agar plate. This method was then applied to detect other fungal species from agar slants and food materials. This method offers a convenient tool for the genotyping of filamentous fungi without using an organic solvent or specialized equipment. 相似文献
984.
985.
Dose-dependent hypocholesterolemic actions of dietary apple polyphenol in rats fed cholesterol 总被引:4,自引:1,他引:3
Osada K Suzuki T Kawakami Y Senda M Kasai A Sami M Ohta Y Kanda T Ikeda M 《Lipids》2006,41(2):133-139
The dose-dependent hypocholesterolemic and antiatherogenic effects of dietary apple polyphenol (AP) from unripe apple, which
contains approximately 85% catechin oligomers (procyanidins), were examined in male Sprague-Dawley rats (4 wk of age) given
a purified diet containing 0.5% cholesterol. Dietary AP at 0.5 and 1.0% levels significantly decreased the liver cholesterol
level compared with that in the control (AP-free dietfed) group. Dietary AP also significantly lowered the serum cholesterol
level compared with that in the control group. However, the HDL cholesterol level was significantly higher in the 1.0% AP
fed group than in the control group. Accordingly, the ratio of HDL-cholesterol/total cholesterol was significantly higher
in the 0.5% AP-fed group and 1.0% AP-fed group than in the control group. Moreover, the atherogenic indices in the 0.5 and
1.0% AP-fed groups were significantly lower than those in the control group. The activity of hepatic cholesterol 7α-hydroxylase
tended to be increased by dietary AP in a dose-dependent manner. In accord with this observation, dietary AP increased the
excretion of acidic steroids in feces. Dietary AP also significantly promoted the fecal excretion of neutral steroids in a
dose-dependent manner. These observations suggest that dietary AP at 0.5 or 1.0% level exerts hypocholesterolemic and antiatherogenic
effects through the promotion of cholesterol catabolism and inhibition of intestinal absorption of cholesterol. 相似文献
986.
Sudhir E. Dapurkar Hajime Kawanami Toshirou Yokoyama Yutaka Ikushima 《Topics in Catalysis》2009,52(6-7):707-713
Oxidation of oleic acid was performed over various ordered porous catalysts containing transition metal in supercritical carbon dioxide (scCO2) media with molecular oxygen. Oleic acid was completely decomposed into mono- and dicarboxylic acids over porous catalysts, viz., mesoporous molecular sieves (CrMCM-41, MnMCM-41, CoMCM-41) and microporous molecular sieves (CrAPO-5, CoMFI, MnMFI) using scCO2 at 353 K for 8 h. Among the different catalysts studied, microporous and mesoporous catalysts containing chromium, in presence of scCO2 showed high distribution of azelaic and pelargonic acids as compared to their analogs containing cobalt or manganese. The presence of scCO2 medium with the catalysts increased the distribution of azelaic and pelargonic acids. The effect of CO2 pressure, reaction temperature and reaction time on oxidation of oleic acid over CrMCM-41 was also investigated. Additionally it is noticed that the catalyst can be recycled with negligible loss of catalytic activity. 相似文献
987.
Nobuhiro Moteki Yutaka Kondo Nobuyuki Takegawa Shin-ichi Nakamura 《Journal of aerosol science》2009,40(9):790-801
The directional intensity distribution of thermal emission from nonspherical particles can be predicted in the geometric optics limit using the Kirchhoff's law, or, in general case, using the Rytov's theory based on the fluctuation–dissipation theorem. This study demonstrates the first experimental evidence of the directional variation of thermal emission from nonspherical particles of a size smaller than the geometric optics limit. We used a method of laser-induced incandescence with multi-angle detectors to observe the directional dependences of thermal emission from individual carbon particles. For laboratory carbon particles with various shapes, the measured directional dependences of thermal emission were consistent with theoretical calculations for model nonspherical particles. This study provides a new physical principle for measuring the shape of aerosols according to the directional dependence of their thermal emission and is especially useful for online, in situ shape classification of carbon particles. 相似文献
988.
Wind characteristics of a strong typhoon 总被引:1,自引:0,他引:1
Shuyang Cao Yukio Tamura Mamoru Saito Yutaka Matsuzaki 《Journal of Wind Engineering & Industrial Aerodynamics》2009,97(1):11-21
The wind characteristics of a strong typhoon (Typhoon Maemi 2003) are analyzed on the basis of 10 min wind speed samples. The wind speeds were measured simultaneously by nine vane and seven sonic anemometers at a height of about 15 m. Turbulence intensity and scale, gust factor, peak factor, decay factor of the coherence function, probability distribution function, power spectrum, and their variations with wind speed are obtained. Wind-direction-dependent analysis is conducted on the wind characteristics. Turbulence intensity decreases with wind speed and remain almost constant when the wind speed becomes high. The averaged values of gust factor and peak factor are 1.6 and 3.3, respectively. The spatial cross correlation and decay factor of the coherence function increase slightly with wind speed. The probability density function of fluctuating wind speed of a strong typhoon follows a Gaussian distribution, and the power spectrum of strong wind can be expressed by a Karman-type spectrum at the low frequency. The wind characteristics of this strong typhoon are shown to be very similar to those of non-typhoon winds. 相似文献
989.
Toshihiko Osaki Kiho Yamada Koji Watari Koji Tajiri Saori Shima Takeshi Miki Yutaka Tai 《Catalysis Letters》2012,142(1):95-99
Abstract
Palladium-alumina cryogel was prepared from palladium nitrate and aluminum sec-butoxide through a sol–gel processing and subsequent freeze drying. The cryogel showed higher thermal stability of palladium and catalytic CO oxidation activity than the corresponding xerogel and impregnation catalysts. The superior stability and activity were ascribed to the uniform distribution of palladium ions in the boehmite gel by the one-pot preparation of palladium-boehmite co-gel, and also to the suppression of transfer and aggregation of the metal during the subsequent freeze drying. As a result palladium ions were finely distributed and stabilized throughout the alumina cryogel support, which consequently suppressed the sintering of palladium at elevated temperatures. 相似文献990.
T.N. Narayanan Zheng Liu P.R. Lakshmy Wei Gao Yutaka Nagaoka D. Sakthi Kumar Jun Lou Robert Vajtai P.M. Ajayan 《Carbon》2012,50(3):1338-1345
A simple and scalable method for the synthesis of reduced graphene oxide (RGO) based conductive and magnetic multifunctional films (membranes) is reported. A RGO–iron oxide (Fe3O4) freestanding film is fabricated using a versatile chemical route followed by vacuum infiltration. Temperature dependent electronic transport properties of the magnetic GO and RGO films were measured using a four probe technique from room temperature to 15 K. A conduction mechanism based on variable range hopping is suggested for explaining of the electronic conductivity variations. Possible applications of this multifunctional membrane are also discussed. 相似文献