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101.
Takegawa Y Araki K Fujitani N Furukawa J Sugiyama H Sakai H Shinohara Y 《Analytical chemistry》2011,83(24):9443-9449
Glycosaminoglycans (GAGs) play important roles in cell adhesion and growth, maintenance of extracellular matrix (ECM) integrity, and signal transduction. To fully understand the biological functions of GAGs, there is a growing need for sensitive, rapid, and quantitative analysis of GAGs. The present work describes a novel analytical technique that enables high throughput cellular/tissue glycosaminoglycomics for all three families of uronic acid-containing GAGs, hyaluronan (HA), chondroitin sulfate (CS)/dermatan sulfate (DS), and heparan sulfate (HS). A one-pot purification and labeling procedure for GAG Δ-disaccharides was established by chemo-selective ligation of disaccharides onto high density hydrazide beads (glycoblotting) and subsequent labeling by fluorescence. The 17 most common disaccharides (eight comprising HS, eight CS/DS, and one comprising HA) could be separated with a single chromatography for the first time by employing a zwitter-ionic type of hydrophilic-interaction chromatography column. These novel analytical techniques were able to precisely characterize the glycosaminoglycome in various cell types including embryonal carcinoma cells and ocular epithelial tissues (cornea, conjunctiva, and limbus). 相似文献
102.
Hideaki Itoh Hisaaki Takao Hiroyasu Iwahara 《Journal of the American Ceramic Society》1993,76(11):2889-2895
Reaction sintering behavior of cBN, which is accompanied by the transformation from hBN to cBN in the presence of 30 wt% diamond seed grains, was investigated under high pressure conditions (6.0–7.5 GPa, 1400–1700°C, 0–30 min) using volatile catalysts such as NH4 NO3 , NH4 Cl, and NH2 NH2 . Fully dense sintered compacts having a Vickers microhardness of more than 5000 kg/mm2 were prepared with no residual catalytic solid components. The activation energy for the conversion from hBN to cBN was 200–230 kJ/mol. Adsorbed N2 , H2 , and/or NH x components which were formed by decomposition of these catalysts during high pressure and temperature treatments, would have a favorable kinetic effect on cBN formation from hBN and its simultaneous sintering. 相似文献
103.
Hideaki Inaba 《Journal of the American Ceramic Society》1995,78(11):2907-2912
The effect of oxygen nonstoichometry on physical and magnetic properties of a Mn-Zn ferrite has been studied by using annealed samples under various oxygen pressures and temperaure. The dependence of oxygen nonstoichiometry7 on disaccommodation and Fe2+ content changed at the stoichiometric composition, and the lattice parameter became maximum at the stoichiometric composition. These results suggest that Mn-Zn ferrites have two different defect structures: cation vacancies in cation-deficient regons and oxygen vacancies in anion-deficient regions. Initial permeability was maximum and power loss was minimum at the stoichiometric composition, suggesting he importance of the number of point defects for the magnetic properties. 相似文献
104.
Hideki Nishida Kunio Matsumura Hideaki Kurokawa Atsushi Hoshino Seishi Masui 《Journal of the Society for Information Display》2005,13(10):841-848
Abstract— The perfluorocarbons (PFCs) used as etching‐process and chamber‐cleaning gases in the manufacture of LCD devices have a high global‐warming potential and a long atmospheric lifetime. Thus, to voluntarily reduce these environmentally harmful PFCs, in 2001 the Japanese LCD association established the World LCD Industry Cooperation Committee (WLICC), together with its counterpart associations in the Republic of Korea and Taiwan. Since that time involving many discussions, the WLICC reached a consensus on reducing the aggregate absolute PFC emissions to the equivalent of less than 0.82 million metric tons of carbon by 2010. Each association has been taking whatever emission reduction steps it considers best to achieve this goal. Thanks to these measures, the PFC emissions from the Japanese LCD industry have remained at the same level, or less, than those of the year 2000, in spite of the fact that PFC purchases have continually increased. In the interim, the Japanese LCD association has been obtaining experimental data for the 2006 IPCC Inventory Guidelines, which will give the emission factors needed to estimate the PFC emissions. As a result, some data are quite different from emission factors given in the current 2000 Inventory Guidelines. All the data obtained have been submitted to the IPCC to be adopted in the new 2006 Guidelines. 相似文献
105.
Thermal properties of diamond/copper composite material 总被引:8,自引:0,他引:8
Thermal considerations are becoming increasingly important for the reliabilities of the electronics parts as the electronics technologies make continuous progress such as the higher output power of laser diodes or the higher level of integration of ICs. For this reason the desire for improving thermal properties of materials for electronics component parts is getting stronger and the material performance has become a critical design consideration for packages. To meet the demands for a high performance material for heat spreader materials and packages, a new composite material composed of diamond and copper was successfully manufactured under high pressure and high temperature. The effects of diamond particle sizes and the volume fractions of diamond on both thermal conductivity and the coefficient of thermal expansion (CTE) were investigated. The thermal conductivity of the composite material was dependent on both the particle size and the volume fraction of diamond, while the CTE was dependent only on the volume fraction of diamond. At the higher diamond volume fraction, the experimentally obtained thermal conductivities of the composite materials were above the theoretically expected values and the experimentally obtained CTE were between the two theoretical Kerner lines. This may be due to the fact that at the higher diamond volume fraction the diamond particles are closely packed to form bondings between each particle. The composite of diamond and copper have a potential for a heat spreading substrate with high performance and high reliability because not only its thermal conductivity is high but its coefficient of thermal expansion can be tailored according to a semiconductor material of electronics devices. 相似文献
106.
This paper deals with a self‐commutated BTB (Back‐To‐Back) system for the purpose of power flow control and/or frequency change in transmission systems. Each BTB unit consists of two sets of 16 three‐phase voltage‐source converters, and their AC terminals are connected in series to each other via 16 three‐phase transformers. Hence, the BTB unit uses totally 192 switching devices capable of achieving gate commutation. This results in a great reduction of voltage and current harmonics without performing PWM control. Simulation results verify the validity of the proposed system configuration and control scheme not only under a normal operating condition but also under a single line‐to‐ground fault condition. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 143(3): 68–78, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10124 相似文献
107.
Low resistivity transparent conducting Al-doped ZnO films prepared by pulsed laser deposition 总被引:1,自引:0,他引:1
Hideaki Agura Akio SuzukiTatsuhiko Matsushita Takanori AokiMasahiro Okuda 《Thin solid films》2003,445(2):263-267
A series of AZO films were grown on glass substrates by a method of pulsed laser deposition using a split target divided into AZO (Al2O3: 1 wt.%) and AZO (Al2O3: 2 wt.%). The film deposition took place at a substrate temperature of 230 °C within a magnetic field applied perpendicularly to the plume. To suppress the droplet generation caused by the intense laser energy, the laser energy density was reduced to 0.75 J/cm2 (15 mJ). For an approximately 280-nm thick-AZO film grown at a target-to-substrate distance of 25 mm, we obtained the lowest resistivity of 8.54×10−5 Ω·cm and an average transmittance of more than 88% in the visible range. In the cross-sectional TEM observation and XRD spectra, the regularity in the crystal growth was generated immediately from the interface between the substrate and the film. 相似文献
108.
Measures preventing an earthquake-induced soil liquefaction are of significant importance to mitigate the liquefaction hazards. An air-injection technique may be a simple, inexpensive method - this leads the saturated soils to the desaturated by injecting pressurized air, resulting in a higher liquefaction strength and lower susceptibility. The objective of this study is to investigate the evolution of desaturation process during air injection into saturated soil deposits and verify the validity of a multiphase flow simulator if it is capable of being applied for predicting the process as well as the distribution of degree of saturation after the air injection ceased. In this study simplified model tests that simulate the air injection into saturated soils using air-injection probes, are conducted using two different sizes of soil containers. The experiments using the small container are aimed to examine the nominal rates and magnitudes of the soil desaturation driven by air injection, whilst those with the large container are performed to obtain not only the rates and magnitudes but also the distributions of the desaturated zones within the soil. The results obtained indicate, although clearly depending on the physical properties of targeted soils, that the evolution of desaturation is strongly controlled by the air pressures injected and the soil permeabilities. Numerical analyses are also conducted using a multiphase flow simulator to describe the evolution of the soil desaturation, and to examine the applicability of the model as a prediction tool enabling an evolution of desaturation in situ to be followed with time and space. Predictions show a relatively good agreement with the experimental measurements regarding the rates, magnitudes, and distribution of desaturation specifically for the small-container experiments although predictions of desaturated domain slightly overestimate the measurements for the large-container experiments. Thus, this study indicates that the numerical model described is applicable to field problems when the soil properties in terms of flow transport are well-constrained. 相似文献
109.
Tsuneaki Matsudaira Hideaki Itoh Shigeharu Naka Hiroshi Hamamoto Mikio Obayashi 《Journal of Materials Science》1988,23(1):288-292
TiB2 powder was synthesized by solid state reaction using amorphous boron and TiN as a source of titanium. The TiB2 formation did not occur at all in a nitrogen atmosphere even at 1400° C. TiB2 formed above 1100° C in argon and hydrogen atmospheres. The only crystalline phase of TiB2 powder was favourably synthesized at 1400° C for 360 min in an argon atmosphere from a starting powder with a composition containing excess boron (B/Ti = 2.2). The synthesized powder was well dispersed and had a particle size of 0.5 to 2 µm. The powder activity was evaluated by sintering at 4 G Pa and 1300 to 1600° C for 15 min. 相似文献
110.
Ionic crosslinking of carboxyl-terminated liquid rubbers with metal oxides and metal carbonates, mainly with the former, were investigated. The liquid rubbers used were a polymer of butadiene (Hycar CTB 2000X162) and a copolymer of butadiene–acrylonitrile (Hycar CTBN 1300X8). The CTBN ionically crosslinked rubbers obtained showed higher tensile strength than the CTB series, due to the polarity effect of the nitrile groups. The ionic rubbers cured with MgO and CaO were studied in detail, and it was found that their tensile strength increased markedly with increase in the metal oxides used, and in addition white carbon and carbon black showed remarkable reinforcing effects. The properties such as tensile strength, elongation, Shore A hardness, and melt index are influenced by humidity. It is characteristic of these ionically crosslinked rubbers that they can be successfully reprocessed. 相似文献