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41.
Thermal Diffusion of Si Atoms at the Interface of Mo/Si Bilayers Studied with a Soft X-ray Emission Microscope 总被引:1,自引:1,他引:0
1 Introduction Thepropertyofthedeviceswithalayerstruc turesuchassuperlattices,multilayercoatings,andsemiconductordevicesisdependentuponthequali tyoftheinterfacebetweenadjacentlayers.Fromtheviewpointoftheirpracticalusage,thermalsta bilityoftheinterfaceis… 相似文献
42.
An impedance analyzer or the Schering bridge is usually used for measurement of the medium-wave antenna impedance. However it has been said to be impossible to measure the exact antenna impedance under a high-intensity electric field environment generated by such as a neighboring radio station, especially with the same operating frequency because an undesired large signal is induced at the antenna input port. We propose a new measurement method and an instrument using a double synchronized detection, which has a function to suppress undesired signals efficiently. Here a double synchronous detecting technique is introduced to suppress the undesired signal with the same frequency as a measurement frequency. This system makes it possible to easily measure the antenna impedance with higher accuracy even under such an environment and also is useful for periodical maintenance of the transmitting antenna without interruption of broadcasting services in the daytime. 相似文献
43.
Noboru Ohta 《Color research and application》1985,10(3):156-164
A standard deviate observer (SDO) has been formulated that can predict the average color mismatches of metameric color pairs by 20 Stiles' observers. A nonlinear optimization technique, rather than a statistical analysis, has been employed to derive it. The colorimetric characteristics of the present SDO are compared with those of SDOs previously proposed. 相似文献
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Morphology development during the crystallization of poly(vinylidene fluoride) (PVDF)/poly(methyl methacrylate) (PMMA) blends was investigated at various crystallization temperatures (TC) by means of time-resolved light scattering measurements and atomic force microscopy (AFM). A coarse spherulite obtained at a high TC of 162 °C was found to be developed with a two-step crystallization process. The ordering in the spherulites (Pr) increased with time at the early stages and then decreased at the later stages. The rate of spherulite growth started to decrease when Pr started to decrease. In contrast, in the compact spherulite obtained at a low TC of 148 °C, Pr decreased monotonously with time while the growth rate was constant. AFM observation revealed that such characteristic crystallization behavior is attributed to the exclusion of PMMA from the crystal growth during the crystallization; i.e., the amount of excluded PMMA becomes larger as the distance from the spherulite center increases and the crystallization temperature rises. 相似文献
46.
采用无偏振片反射式LCD及超低功耗驱动技术制造移动显示器件 总被引:1,自引:1,他引:0
Kiyoshi Minoura Yasushi Asaoka Eiji Satoh Takashi Satoh Ichiro Ihara Sayuri Fujiwara Akio Miyata Yasuhisa Itoh Seijiro Gyoten Noboru Matsuda Yasushi Kubota 代永平 《现代显示》2010,(7):5-9,35
我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。 相似文献
47.
Numata M Nakamura N Koshikawa H Terashima Y 《Environmental science & technology》2002,36(20):4389-4394
Chlorine isotope fractionation during reductive dechlorination of trichloroethene (TCE) and tetrachloroethene (PCE) to cis-1,2-dichloroethene (cDCE) by anaerobic bacteria was investigated. The changes in the 37Cl/35Cl ratio observed during the one-step reaction (TCE to cDCE) can be explained by the regioselective elimination of chlorine accompanied by the Rayleigh fractionation. The fractionation factors (alpha) of the TCE dechlorination by three kinds of anaerobic cultures were approximately 0.994-0.995 at 30 degrees C. The enrichment of 37Cl in the organic chlorine during the two-step reaction (PCE to cDCE) can be explained by the random elimination of one chlorine atom in the PCE molecule followed by the regioselective elimination of one chlorine atom in the TCE molecule. The fractionation factors for the first step of the PCE dechlorination with three kinds of anaerobic cultures were estimated to be 0.987-0.991 at 30 degrees C using a mathematical model. Isotope fractionation during the first step would be the primary factor for the chlorine isotope fractionation during the PCE dechorination to cDCE. The developed models can be utilized to evaluate the fractionation factors of regioselective and multistep reactions. 相似文献
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49.
Hidetaka Yoshikawa Katsuya Fukuyama Yoichiro Nakahara Takehisa Konishi Nobuyuki Ichikuni Yasuko Yoshikawa Noboru Akuzawa Yoichi Takahashi Keiko Nishikawa 《Carbon》2003,41(15):2931-2938
The structure of bromine residue compounds was investigated by X-ray absorption fine structure (XAFS) in order to interpret where and how bromine is present in carbons with different degrees of graphitization. The residue compounds can be classified into three groups, as obtained from X-ray absorption near edge structure (XANES) spectra and the values of the intramolecular distance rBr–Br determined by extended X-ray absorption fine structure (EXAFS). In Group I, prepared from the host carbons heat treated at temperatures higher than 1900 °C, bromine exists in the interlayer space of graphite in the form of Br2 molecules with interaction of the π electrons of graphite. In Group III, from carbon heat treated at 1000 °C, most of the bromine probably reacts with carbon atoms having a dangling bond or functional groups. For Group II, where the host carbons are heat treated at intermediate temperatures, it is likely that bromine exists in undeveloped defects with a unique electronic state. 相似文献
50.
高档的通信设备曾一度只能在办公环境中才能使用,然而现在这种情况已经改变,家庭中已经普遍具备了互连能力,许多家用电子设备现在通过Ipv6和其他技术已经具备了上网能力。随着宽带通信应用的增加,调制解调器、各种DSL接入复用器以及其他类似设备的安装已经遍及办公室和家庭,消费者可以方便获得价廉的通信设备。对于设备制造商来说,这些装置必须满足安全标准,如IEC60950(InternationalElectrotechnicalCommission第三版),它要求在与数据通信线连接的设备上实现电话网络高压电路的隔离。一般情况下,人们采用传统的电磁通信继电器来开关内… 相似文献