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81.
Kouji Maeda Tetsuo Ikari Yoshito Akashi Koji Futagami 《Journal of Materials Science》1994,29(6):1449-1454
Two large exothermic reaction peaks at 658 and 690 K are observed in the differential scanning calorimetric (DSC) curve for the amorphous metallic alloy, Ni65Cr16P19. Extensive DSC and X-ray diffractometer measurements were carried out for pre-annealed samples, and it is concluded that the two peaks are due to crystallization of Ni and stable Ni3P phases, respectively. The expanded lattice constants of these phases can be explained by assuming that a small amount of Cr atoms were dissolved in these crystalline phases. As for the metastable Ni3P phase, confirmation of its presence by X-ray measurement could not be obtained. These results may be interpreted by considering that the metastable phase appears only in the thin film region of the sample. 相似文献
82.
Y Miura R Shimazu K Miyake S Akashi H Ogata Y Yamashita Y Narisawa M Kimoto 《Canadian Metallurgical Quarterly》1998,92(8):2815-2822
RP105 was originally discovered as a mouse B-cell surface molecule that transmits an activation signal. The signal leads to resistance against irradiation-induced apoptosis and massive B-cell proliferation. Recently, we found that mouse RP105 is associated with another molecule, MD-1. We have isolated here the human MD-1 cDNA. We show that human MD-1 is also associated with human RP105 and has an important role in cell surface expression of RP105. We also describe a monoclonal antibody (MoAb) that recognizes human RP105. Expression of RP105 is restricted to CD19(+) B cells. Histological studies showed that RP105 is expressed mainly on mature B cells in mantle zones. Germinal center cells are either dull or negative. RP105 is thus a novel human B-cell marker that is preferentially expressed on mature B cells. Moreover, the anti-RP105 MoAb activates B cells, leading to increases in cell size, expression of a costimulatory molecule CD80, and DNA synthesis. The B-cell activation pathway using RP105 is conserved in humans. 相似文献
83.
Kuskibiki J. Akashi N. Sannomiya T. Chubachi N. Dunn F. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1995,42(6):1028-1039
A new system and method for characterizing biological tissues in vitro and liquids in the VHF and UHF ranges is described. Bulk acoustic properties such as the sound velocity, attenuation, acoustic impedance, and density are determined in reflection and transmission modes, with the biological tissue/liquid specimen sandwiched between the parallel surfaces of synthetic silica glass buffer rods having ZnO piezoelectric film transducers on their opposite ends. The method is an ultrasonic transmission line comparison method wherein the reference medium is distilled water, for which all acoustic properties are known. Measurement errors due to diffraction losses in the acoustic media and to mode conversion at the buffer/sample interfaces are corrected. Special techniques for achieving precise parallelism between the two rod surfaces, for movement to adjust the gap distance, and for signal processing are employed in order to obtain high measurement accuracy. Attenuation and reflection coefficients are determined using the gated pulse echo method. The sound velocity is determined with the gated pulse interference method by sweeping the ultrasonic frequency, or by changing the gap distance. Results of measurements on castor oil, cottonseed oil, silicone oil, and bovine liver, in the frequency range from 10 to 500 MHz, are presented and compared with results of earlier reports 相似文献
84.
Suzuki H. Takeuchi T. Akashi F. Yamaguchi T. 《Selected Areas in Communications, IEEE Journal on》1988,6(9):1556-1564
The authors discuss and propose a very-high-speed and high-capacity packet-switching (HPS) architecture for a future broadband ISDN (integrated-services digital network). The HPS network accommodates various communication services, such as voice, high-speed data, high-speed still picture, and video services. The proposed architecture has three significant principles: a high-speed oriented simple network protocol, separation of signaling and network control from data transfer, and hardware switching. These principles provide fast- and high-throughput transmission for data packets and reliable transmission and processing for call-control packets. The HPS protocol structure is addressed, which provides high flexibility for various communications services as well as high-speed capability. A 3-Gb/s capacity and building-block-structured packet-switching system architecture, using bus- and loop-type switch fabric, is also presented 相似文献
85.
Dynamic compaction experiments were carried out on fine Si3N4 powder, that contained no additives, using maximum pressures of from 20 to 77 GPa. With pressures of from 20 to 64 G Pa the relative densities of the resulting Si3N4 compacts were the same: 96% of the theoretical density, but their microhardness values differed significantly. The optimum shock pressure for the Si3N4 powder with an initial density of 60% was near 44 G Pa. At this pressure, sintered Si3N4 compacts with a density of 96% of the theoretical density and a microhardness of 21.2 G Pa were obtained. However, at 64 G Pa, -Si3 N4 was transformed to -Si3N4 as a result of the high temperatures experienced during the compaction process. Because of this transformation, the microhardness of the compacted Si3N4 was reduced significantly. 相似文献
86.
87.
The main purpose of this study is to reveal the relationship between the building density and the average wind velocity at pedestrian level in residential neighborhoods. This paper firstly presents the results of wind tunnel tests on 22 residential neighborhoods selected from actual Japanese cities. The results show that there is a strong relationship between the gross building coverage ratio and the mean wind velocity ratio. Secondly, the wind environment evaluation for case study areas is performed by using the wind tunnel results and the climatic conditions of several major Japanese cities. The development method of guidelines for realizing acceptable wind environment in residential neighborhoods using the gross building coverage ratio is proposed. 相似文献
88.
Eluted metals from Enshu (a Chinese) and Stratford (an Australian) coal during pretreatments with methanol/water and dilute acetic acid solutions were characterized and quantitatively analyzed by solid-state 23Na NMR, cation chromatography, X-ray fluorescence (XRF), and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) measurements. To achieve the requirements of solvent extracted coal (namely Hyper-Coal: HPC) for its direct utilization to gas turbine system, alkali and alkali-earth metals such as Na, K, and Ca should be removed from coals. A quantitative analytical method of alkali metals with ICP-AES in combination with flow injection system is established for the evaluation of remaining alkali metal contents, especially for the quantitative analysis of Na concentration in the original coal and its HPC. Microwave irradiation acidic digestion pretreatment under controlled high pressure and temperature is very essential to the prompt and quantitative analyses of all the metals in coals and their derived HPC. Combination of ICP-AES with XRF and/or cation chromatography is also effective for the respective analyses of the residue and the extract or filtrate. Solid-state 23Na NMR spectra of the coals before and after solvent soaking pretreatment or acetic acid treatment revealed that ion-exchangeable Na species might be rather selectively eluted by these treatments. It is also suggested that the remaining Na species could not be removed by dilute acetic acid solutions. 相似文献
89.
Biofabrication: Development of Endothelial Cell Networks in 3D Tissues by Combination of Melt Electrospinning Writing with Cell‐Accumulation Technology (Small 2/2018)
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90.
Poly(vinylamine hydrochloride‐co‐N‐vinylformamide) [poly(VAm‐co‐NVF)] with variable VAm content, and a weak polyacid poly(acrylic acid) were assembled on a quartz crystal microbalance (QCM) substrate from their aqueous solutions, thus forming polyelectrolyte multilayers. The effects of varying the VAm content on assembly profiles and film structures were analyzed by quantitative QCM analysis, attenuated total reflection spectra techniques, and atomic force microscopic observation. At a VAm content of less than 40% of the total number of poly(VAm‐co‐NVF) units, the layer‐by‐layer assembly did not proceed, and the frequency shift of the QCM zigzagged with the step number. Above 40% VAm content, the frequency increased continuously with an increasing number of steps. The assembly amount was also maximal at 40% VAm content. The films obtained swelled with water molecules, and this swelling was followed by an increase in thickness in the aqueous phase. The results obtained were compared to those obtained from a combination of poly(VAm‐co‐NVF) and a strong polyacid, poly(sodium styrenesulfonate). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3927–3933, 2006 相似文献