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排序方式: 共有603条查询结果,搜索用时 31 毫秒
111.
Male Sprague-Dawley rats were fed a cholesterol-free (Exp. 1) or cholesterol-supplemented (Exp. 2) diet containing 20% casein
(control group) or 15% defatted squid and 5% casein (defatted squid group), as protein, for 14 d. Serum and hepatic cholesterol
concentrations were lower in rats fed defatted squid than in those fed casein in both cholesterol-free (−20%, P<0.05 and −15%, P<0.05, respectively) and cholesterol-supplemented (−25%, P<0.05 and −15%, P<0.05, respectively) diets. Hepatic triglyceride concentration was lower in the defatted squid than in the control groups
in both cholesterol-free (−51%, P<0.05) and cholesterol-supplemented diets (−38%, P<0.01). The activities of cytosolic fatty acid synthase and the NADPH-generating enzymes, malic enzyme and glucose-6-phosphate
dehydrogenase, in the liver were lower in the defatted squid than in the control groups in both cholesterol-free (−21%, P<0.01, −33%, P<0.05, and −33%, P<0.01, respectively) and cholesterol-supplemented diets (−34%, P<0.05, −57%, P<0.05, and −67%, P<0.05, respectively). The activity of mitochondrial carnitine palmitoyltransferase in the liver was comparable between the
control and defatted squid groups. The activity of Mg2+-dependent phosphatidate phosphohydrolase in the liver cytosol was lower in the defatted squid (−9%, P<0.05) than in the control groups only in the cholesterol-free diet. Fecal excretion of total steroids was stimulated by the
feeding of defatted squid in both cholesterol-free (+77%, P<0.005) and cholesterol-supplemented diets (+29%, P<0.01). These results suggest that the nonlipid fraction of squid exerts a hypocholesterolemic effect by increasing the excretion
of total steroids in feces. The fraction also induces a triglyceride-lowering activity in the liver by decreasing hepatic
lipogenesis. 相似文献
112.
Hiroaki Ashizawa Kiyohara Masakatsu Katsumi Yoshida 《Journal of the American Ceramic Society》2020,103(12):7031-7040
Particle contamination arising from inner ceramic components of the plasma etching equipment has become a serious issue. Yttria (Y2O3) coatings prepared via aerosol deposition (AD) have demonstrated superior plasma resistance in the reduction of particle contamination. The superior particle contamination performance of Y2O3 coatings prepared by AD has been speculatively attributed to its unique microstructure; however, the relationship between the coatings’ microstructure and plasma corrosion behavior has been insufficiently clarified. Herein, we investigated the relationship between the microstructure and plasma corrosion behavior of Y2O3 coatings prepared by the AD method and compared the results with those for coatings prepared by other coating methods. When internal pores are present, these internal pores were selectively plasma corroded; plasma corrosion marks reflecting their pore shape were formed, and the surface roughness increased with increasing plasma exposure time. However, when no internal pores were present, as in the case of the AD coating, the surfaces were homogeneously corroded and maintained their initial surface. As the risk of particle contamination caused by the corrosion of the plasma-resistant coatings is greatly increased with surface roughness, we concluded that the Y2O3 coating prepared via AD will contribute greatly to reducing particle contamination. 相似文献
113.
Karthikeyan Ramachandran Zuccarini Carmine Katsumi Yoshida Toru Tsunoura Doni Daniel Jayaseelan 《Journal of the European Ceramic Society》2021,41(9):4761-4773
Commercially available Ti3SiC2 and Ti2AlC ceramics were used in this study to investigate their wet corrosion and mechanical behaviour as they were under investigation for years for their applications in the field of nuclear as cladding materials and aerospace. The test coupons of dimension 3 × 4 × 40 mm3 and 3 × 4 × 20 mm3 were machined out from commercially available samples for the 3-pt bend test and wet corrosion test, respectively. The water vapour corrosion studies of these samples were carried out at 800 ℃, 1000 ℃, 1200 ℃ for 10, 20 and 100 h in gas flow condition containing 50 % steam + 50 % air. Phase analysis of the as-received Ti3SiC2 and Ti2AlC ceramics revealed the presence of other impurity phases such as TiC and TiSi2. The XRD patterns of the oxidised samples show the formation of rutile as the major phase in both materials. The oxidation layer formed on Ti3SiC2 sample was measured to be 280 μm after exposing the sample in steam for 100 h at 1200 °C. The water vapour corrosion studies reveal that Ti2AlC has high oxidation resistance compared with the Ti3SiC2 due to the formation of protective layers of TiO2 and Al2O3 which resulted in reduced weight gain and oxidation layer thickness. Three-point bend tests were conducted at room temperature for the samples after the water vapour corrosion test at 1000 °C/100 h. The TAC samples showed no degradation in the bending strength (244 MPa) whereas the TSC samples showed reduced strength of 320 MPa. The tensile strength of the samples was measured at room temperature and hydrothermal condition (250 °C and 250 bars pressure) and it was observed that Ti3SiC2 had high tensile strength (190 MPa) in hydrothermal conditions. The tensile strength results were validated using Finite element analysis (FEA) using ANSYS and the FEA results showed a negligible variance of 7 % compared with experimental method. Mathematical modelling based on one dimensional solution of diffusion equation combined with Deal-Grove model was employed to study and compare the oxidation thickness for the linear and parabolic models for the ceramics. The model was effective in validating the oxidation thickness of Ti3SiC2 showing that the experimental thickness was closer to that of mathematical model. 相似文献
114.
Concentrating Single Cells in Picoliter Droplets for Phospholipid Profiling on a Microfluidic System
Weifei Zhang Nan Li Ling Lin Qiushi Huang Katsumi Uchiyama Jin‐Ming Lin 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(9)
Cellular membranes are composed of a variety of lipids in different amounts and proportions, and alterations of them are usually closely related to various diseases. To reveal the intercellular heterogeneity of the lipid variation, an integrated microfluidic system is designed, which consists of droplet‐based inkjet printing, dielectrophoretic electrodes, and de‐emulsification interface to achieve on‐line single‐cell encapsulation, manipulation, and mass spectrometry (MS) detection. This integrated system effectively improves the single‐cell encapsulation rate, and meanwhile reduces the matrix interference and continuous oil phase interference to the MS detection. Using this system, the heterogeneities between the normal and cancer cells are compared, and the heterogeneity of the same cells before and after the drug treatment changed obviously, indicating that this system can be used as a promising tool for studying the link between the alterations of lipid homeostasis and various diseases. 相似文献
115.
116.
Yoshikatsu Ichimura Katsumi Kishino Masaru Kuramoto Mitsunari Satake Atsushi Yoshida 《Journal of Electronic Materials》1995,24(3):171-176
Thermal annealing effects on optical and electrical characteristics for p-type and n-type II–VI compound layers (ZnSe, ZnSSe,
and MgZnSSe) and on the emission efficiency of ZnCdSe/Zn(S)Se 6 quantum well (QW) light emitting diodes (LEDs) grown by molecular
beam epitaxy were investigated. It was clarified that serious degradation of optical and electrical characteristics was not
observed up to an annealing temperature of 400°C. In the case of p-MgZnSSe, the maximum permitted annealing temperature was
lower than that of Zn(S)Se. The light output of the ZnCdSe/Zn(S)Se multi QW LEDs was enhanced by a factor of three at optimum
thermal annealing conditions. The study suggests that this thermal effect for LEDs was produced by the improved crystal quality
of ZnCdSe QWs by thermal annealing. 相似文献
117.
Mummadi VeeracharyAuthor VitaeTomonobu SenjyuAuthor Vitae Katsumi UezatoAuthor Vitae 《Computers & Electrical Engineering》2003,29(1):67-84
An extensive small-signal analysis of a voltage-mode controlled interleaved dual boost (IDB) converter operating in continuous current mode based on signal flow graph approach is proposed. Small-signal flow graph is developed, from which open-loop small-signal transfer functions are derived using well known Mason's gain formula. Closed-loop small-signal input-to-output, control-to-output transfer functions are also derived and frequency response characteristics are determined at different duty ratios. Voltage-mode compensator designed using K-factor approach is used for closed-loop operation of IDB converter. Load voltage regulation against supply voltage and load disturbances are demonstrated through experimental results. 相似文献
118.
Katsumi Mori Harue Wada Robert D. Pehlke 《Metallurgical and Materials Transactions B》1985,16(2):303-312
Desulfurization and dephosphorization reactions of molten iron by soda ash has been studied on laboratory heats of Fe-C, Fe-C-S,
Fe-C-P, and Fe-C-S-P alloys at 1573 and 1623 K. The alloys were melted in helium gas flow and preheated soda ash was added;
metal samples were taken at certain time intervals and analyzed for sulfur, phosphorus, and carbon. Evolved gas samples were
also taken at certain time intervals and analyzed. The phosphorus and sulfur contents in metals decreased rapidly, reaching
the lowest values two to four minutes after the soda ash addition. The degree of desulfurization was generally greater than
that of dephosphorization, and both degrees were higher at lower reaction temperature. The major component of evolved gas
was CO with small amounts of CO2. Phosphorus appeared to form a stable phosphate compound with Na2O, possibly 3Na2O-P2O5, in the slag phase. Soda ash reacts with carbon resulting in decarburization of molten iron and vaporization of sodium; this
reaction may cause the fading of soda ash and can be expressed as: Na2CO3(1) + (1 +x)C = (1 -xNa2O(1) + 2xNa(g_ + (2 +xCO(g). For the phosphorus containing melt, the reaction can be expressed as: Na2CO3(l) +yC + 2x/3P =x(Na2O · 1/3P2O5)(1) + (2 −y − 8x/3)Na2O(l) + 2(−l + y + 5x/3)Na(g) + (1 +y)CO(g) and for the sulfur containing melt: Na2O(l) +C +S = Na2S(l) + CO(g).
Katsumi Mori, Formerly Visiting Associate Research Scientist, University of Michigan, Ann Arbor, MI 相似文献
119.
120.
Katsumi Tawaratani 《Computers & Industrial Engineering》1995,29(1-4):135-140
We are living in an advanced information society. The information revolution in computers is going on, among other areas, in the field of marketing. Until now, the term “Information System” has been used in the field of marketing mainly to refer to market research. We need to make the most of this information to aid decision making in new product development and sales promotion. It is fundamental that marketing be consumer oriented. However, the real needs of a contemporary consumer include factors which cannot be revealed by a questionnaire survey. The progresses of computer technology and its reduction in price has enabled the construction of a network system in the distribution stage.
The construction and application of a network system suitable to contemporary marketing management has now become part of the challenge facing business management. They must collect and process distribution information with speed and efficiency. And they must obtain information that is up-to-minute and sufficiently detailed for marketing activity which can then be carried out effectively with small risk. In other words, a company manager who is supported by an information system has come to be able to control in minute detail the information regarding purchase actions of various consumers. 相似文献