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11.
A high-speed monolithic optical interface switch LSI is developed using a GaAs MSM photodetector and large-scale integrated electric circuits. This LSI operates universally as a 1.8 Gb/s optical-input/optical-output four-channel time-division switch, a 1.8 Gb/s optical-input/electrical-output 1:4 demultiplexer, a 2.0 Gb/s electrical-output 4:1 multiplexer, and a 2.8 Gb/s electrical-input/electrical-output 4×4 space-division switch. It uses a new multistage 2×2 switch block with small hardware and high-speed operation. It can be expanded to a 16×16 optical-input/optical-output time-division switch operating at up to 1.8 Gb/s for broadband-ISDN  相似文献   
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Optical bistability in a Fabry-Perot semiconductor laser amplifier when two optical inputs detuned from the resonant wavelength of a semiconductor laser amplifier are injected is discussed. A split branch is found in the optical output versus input characteristics in addition to conventional optical bistability behavior. It is shown analytically and experimentally that set and reset can be achieved in the optical output of the semiconductor laser amplifier for each wavelength by applying two detuned optical pulses and using the split branch  相似文献   
14.
The prediction of the short-range compact regions of human atrial natriuretic peptide (alpha-hANP), one of the biologically active peptides, has been made by means of the Average Distance Map(ADM). We found out that the location of the predicted short-range compact regions is consistent with the structural units determined by the NMR analysis (Kobayashi et al., 1988). Furthermore, the short-range compact regions correspond well to the biologically active areas of atriopeptin (103-125)-amide (which is homologous peptide to alpha-hANP), detected by the glycine substitution technique (Konishi et al., 1987). The results suggest that a predicted short-range compact region can be regarded as a possible active site in a biologically active peptide.  相似文献   
15.
Certain MHC class I molecules on target cells are known to inhibit the cytotoxic action of NK cells. By using monoclonal antibody (mAb) Cho-1, we have found inhibitory non-MHC class I cell surface molecules that are noncovalently-associated with 200 kDa and 40 kDa antigens. Poly I-C-induced rat NK cells were not cytotoxic to rat fetus-derived fibroblast WFB cell line. In contrast, NK cells were cytotoxic to H-ras oncogene-induced transformants of WFB, W14 and W31. FACS analysis indicated that mAb Cho-1 reacts with WFB, but not with W14 and W31 cells. Thus, this antigen may disappear concomitantly with cell growth and transformation. Cho-1 antigens were also expressed on other NK-resistant lines, such as mouse BALB3T3 fibroblast, EL-4 lymphoma and human fibroblast HEPM. However, they were not expressed on NK-sensitive mouse YAC-1 and H-ras transformant (Brash) of BALB3T3 cells. Furthermore, treatment of target cells with IFN-gamma clearly induced the cell surface expression of Cho-1 antigens, and conferred a resistance to NK cytolysis on target cells. These data strongly suggest that Cho-1 antigen expression may correlate with target cell susceptibility to NK cells. Indeed, treatment of NK-resistant WFB as well as HEPM cells with F(ab')2 fragments of mAb Cho-1 resulted in the acquisition of susceptibility to NK cytolysis. Cho-1 antigens may be novel molecules that regulate the NK resistance of cells.  相似文献   
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An integrated design procedure which is composed of structural design, control design, and actuator locations design is proposed in this paper. First, a composite objective function, formed by a structural and a control objective, is optimized in steady state through the homogenization design method. Then an independent modal space control algorithm (IMSC) is performed on this optimal structure to reduce the dynamic response. Finally, to minimize the control force while still obtaining the same modal response for the controlled modes, the optimal choice for actuator locations is discussed.Part of this paper was presented in the First World Congress of Structural and Multidisciplinary Optimization (held in Goslar, Germany, May 28–June 2, 1995).  相似文献   
18.
The phase equilibria in the pseudo-binary system Bi2O3-TeO2 at 600° 950° C in air were examined by solid-state reaction techniques and X-ray powder diffraction method. Four pseudo-binary compounds appeared, i.e., -Bi2O3 type solid solution having a compositional range of (1-x)Bi2O3·xTeO2 wherex=0 0.4 a new compound Bi6Te2O15 which has an orthorhombic cell of a=2.27(4) nm, b=1.06(1) nm and c = 0.539(8) nm, 2Bi2O3 · 3TeO2, and an unidentified phase Bi2O3·2TeO2. The formation of the phase Bi6Te2O15, in which all the Te ions are hexavalent, was confirmed by the thermogravimetry and by the Mössbauer spectra. The liquidus curves for whole system were determined by DTA method.  相似文献   
19.
利用高速气流冲击法进行粉体/粉体系表面改性技术,是迄今为止各种粉体材料开发中最为引人注目的技术之一。HYBRIDIZATION(下称HYB)系统是利用高速气流冲击法对微粉体进行干式/机械化处理,是使材料复合化的最实用的装置,可对各类有机物、无机物、金属等进行广泛组合,通用性很强,适用于许多行业领域。从本文所述的系统构成、型式,有关的典型球形化处理的运转特性,利用复合化高温粉体测定被处理粉体表面温度,利用颜料改变色调等的处理特点及该系统的适用性等(一部分是从已发表的学术论文及专利上摘录的),可以说明HYB系统的概况。  相似文献   
20.
The catalytic dehydro-aromatization reaction over Mo/HZSM-5 catalyst was drastically stabilized by the co-addition of 5.4% H2 and 1.8% H2O to methane feed at 750 °C, 0.3 MPa and methane space velocity of 3000 mL g−1 h−1, suppressing the coke formation effectively, compared with single hydrogen or steam addition.  相似文献   
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