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排序方式: 共有634条查询结果,搜索用时 15 毫秒
131.
Hideyuki Azegami Shota Fukumoto Taiki Aoyama 《Structural and Multidisciplinary Optimization》2013,47(2):247-258
The present paper introduces a numerical solution to shape optimization problems of domains in which boundary value problems of partial differential equations are defined. In the present paper, the finite element method using NURBS as basis functions in the Galerkin method is applied to solve the boundary value problems and to solve a reshaping problem generated by the H1 gradient method for shape optimization, which has been developed as a general solution to shape optimization problems. Numerical examples of linear elastic continua illustrate that this solution works as well as using the conventional finite element method. 相似文献
132.
Shibuya K Koshimizu M Asai K Muroya Y Katsumura Y Inadama N Yoshida E Nishikido F Yamaya T Murayama H 《The Review of scientific instruments》2007,78(8):083303
We introduce experimental systems which use accelerators to evaluate scintillation properties such as scintillation intensity, wavelength, and lifetime. A single crystal of good optical quality is often unavailable during early stages in the research and development (R&D) of new scintillator materials. Because of their beams' high excitation power and/or low penetration depth, accelerators facilitate estimation of the properties of early samples which may only be available as powders, thin films, and very small crystals. We constructed a scintillation spectrum measurement system that uses a Van de Graaff accelerator and an optical multichannel analyzer to estimate the relative scintillation intensity. In addition, we constructed a scintillation time profile measurement system that uses an electron linear accelerator and a femtosecond streak camera or a microchannel plate photomultiplier tube followed by a digital oscilloscope to determine the scintillation lifetimes. The time resolution is approximately 10 ps. The scintillation spectra or time profiles can be obtained in a significantly shorter acquisition time in comparison with that required by conventional measuring systems. The advantages of the systems described in this study can significantly promote the R&D of novel scintillator materials. 相似文献
133.
Xiaoxiang Jiang Naoko Ellis Zhaoping Zhong 《Korean Journal of Chemical Engineering》2011,28(1):133-137
There has been an increasing interest in alternative fuels made from biomass which is abundant and renewable. Bio-oil and bio-diesel seem to be such promising liquid fuels. Bio-oil produced by fast pyrolysis of biomass is highly viscous, acidic, and has high water content. To overcome these problems as a fuel, a method of emulsifying bio-oil with bio-diesel was performed in the previous paper, and a stable mixture of bio-oil and bio-diesel was successfully prepared. In this paper, several properties of the mixture are discussed by using TG, FTIR and 1H NMR. The results show us that, compared with crude bio-oil, some properties of bio-oil/bio-diesel mixture such as water content, acid number, viscosity are much improved. The thermal decomposition of the mixture under air/nitrogen is shown using a thermogravimetric analyzer (TGA). Further information about the functional groups is exhibited through Fourier Transform infrared spectrometer (FTIR) and nuclear magnetic spectroscopy (NMR). 相似文献
134.
Christopher K. Lee Naoko Araki Drew S. Sowersby L. Kevin Lewis 《Yeast (Chichester, England)》2012,29(2):73-80
Extraction of high molecular weight chromosomal DNA from yeast cells is a procedure that is performed frequently for experiments involving polymerase chain reaction (PCR), Southern blotting and other DNA analysis techniques. We have investigated several parameters affecting DNA yield and quality, using a simple chemical‐based purification procedure that was modelled on alkaline lysis methods developed for bacterial cells. The three major steps of the procedure, cell lysis, protein removal and DNA precipitation, were optimized by testing the impacts of several chemicals, including sodium dodecyl sulphate (SDS), sodium hydroxide, Tris buffer, sodium acetate and potassium acetate. Other parameters, such as the effect of elevated temperatures on cell lysis, were also investigated. A rapid, optimized protocol was derived for the purification of DNA from small cell cultures that can be readily digested with restriction enzymes and used as a template for PCR. Average yield was calculated to be approximately 1.7 µg DNA/108 cells, which is similar to the theoretical maximum amount obtainable from haploid yeast cells. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
135.
Takahiro Hayasaka Naoko Goto-Inoue Nobuhiro Zaima Yoshishige Kimura Mitsutoshi Setou 《Lipids》2009,44(9):837-848
Imaging mass spectrometry (IMS) has been developed as a method for determining and visualizing the distribution of proteins
and lipids across sections of dissected tissue. Although lipids play an important role in mammal development, their detailed
distributions have not been analyzed by conventional methods. In this study, we tried to determine and visualize lysophosphatidylcholine
(LysoPtdCho) and triacylglycerol (TAG) in a mouse embryo by matrix-assisted laser desorption/ionization (MALDI) hybrid quadrupole
time-of-flight (TOF) mass spectrometer. Many peaks were detected from a raster scan of the whole embryonic sections. The peaks
at m/z 496.33, 524.36, 879.72, 881.74, and 921.74 were identified by MS/MS analyses as [LysoPtdCho (16:0) + H]+, [LysoPtdCho (18:0) + H]+, [TAG (16:0/18:2/18:1) + Na]+, [TAG (16:0/18:1/18:1) + Na]+, and [TAG (16:0/20:3/18:1) + K]+, respectively. The ion images constructed from the peaks revealed that LysoPtdCho were distributed throughout the body and
TAGs were distributed around the brown adipose tissue and in the liver at embryo day 17.5. Thus, IMS system based on MALDI
hybrid quadrupole TOF MS revealed the distribution of LysoPtdCho and, more importantly, the organ-specific distribution of
TAGs in the embryonic stages of mammals for the first time. We can conclude that this technique enables us to analyze the
roles of various lipids during embryogenesis and gives insight for lipid research. 相似文献
136.
Zyun Siroma Naoko FujiwaraTsutomu Ioroi Shin-ichi YamazakiHiroshi Senoh Kazuaki YasudaKazumi Tanimoto 《Journal of power sources》2007
To measure local phenomena in a PEMFC during a transitional state induced by changing of the feeding gas, a segmented cell was fabricated and the local current and local potential distribution were measured under open-circuit conditions. The anode or cathode was divided into 97 segments of 1.5 mm each. A change in the anode gas from nitrogen or oxygen to hydrogen induced momentary internal currents among the segments. The potential distribution in the electrolyte was observed simultaneously using three quasi-reference electrodes located locally. The results supported the reverse-current decay mechanism, which is known to be a mechanism of cathode degradation. Furthermore, internal currents were observed when the cathode gas was changed from nitrogen to oxygen. While the cathode was not subjected to a harmful potential, a large potential distribution was induced in the anode. 相似文献
137.
Solder microbumps of 0.95Sn-0.05Au were successfully fabricated on a compound semiconductor wafer by reflowing a multilayer
metal film in hydrogen plasma atmosphere. The microbumps melt at as low a temperature as 220°C, which is close to the lowest
eutectic temperature (217°C) in a Sn-Au system. Fluxless reflowing was achieved by using hydrogen radicals. The low-temperature
fluxless fabrication of Sn-Au solder microbumps is a very useful technique for electrical connection between a compound semiconductor
chip and a substrate. 相似文献
138.
Mukaiyama Koki Arao Susumu Matsui Shota Nakagawa Masao Hirogaki Toshiki Aoyama Eiichi 《Forschung im Ingenieurwesen》2019,83(3):445-459
Forschung im Ingenieurwesen - Hypoid gears are widely used in automobile differentials. Furthermore, it is well known that the efficiency of hypoid gears is lower than that of other gears due to... 相似文献
139.
140.
Upon photoirradiation at 365 nm, platelike microcrystals of trans-4-aminoazobenzene quickly bend away from the light source, returning to their initial linear shape when irradiation was terminated. However, relative to the observations upon cessation of 365 nm irradiation, the bent crystals recovered their initial shape more rapidly when exposed to visible light (530 nm) irradiation. 相似文献