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51.
A theoretical study has been carried out in order to explain the sensitivities of electron beam and X-ray resists. A preliminary investigation reveals that the behavior of these resists, on irradiation by high energy radiation, may be considered to be the electronically-excited species in the polymer. To elucidate the chemical reactions in the excited states the adiabatic potential curves are calculated by the INDO/S procedure, which considers all the valence electrons and all the singly excited electronic configurations. Polyethylene and polyisobutylene were chosen as representative of crosslinkable and degradable polymers, respectively, since there is a parallelism between the beam sensitivity of resists and the effects of high energy radiation on polymers. Polyisobutylene has many antibonding curves favorable for the main chain scission in the excited states and polyethylene does not except for one improbable state. It was concluded that degradability is explainable by the ease of bond fission in the excited states; the crosslinkability is considered to be nondegradable property.  相似文献   
52.
An all-optical device in which a nonlinear etalon is operated stably as a triode switch at a high on-off ratio is discussed. A nonlinear etalon is sandwiched between two quarter-pitch GRIN (graded index) lenses. Detuning is adjusted by using the position-to-angle conversion feature of the lens. Two orthogonally polarized beams are used to obtain a high on-off ratio (~10:1) even for a weak signal beam by completely separating a control beam from an output beam  相似文献   
53.
Japan Atomic Energy Agency (JAEA) has developed a grout database (GDB) comprising the latest technical data of grout materials relevant to the geological disposal of high-level radioactive waste (HLW). Currently, only newly developed grout materials of low pH cements, superfine spherical silica and colloidal silica, which are expected to provide a target pH ≤ 11 leachate, are included in the GDB. Case examples from on-site works and laboratory-based tests that have been published in the literature have been used to add construction and material details to the GDB. The GDB is available online (https://groutdb.jaea.go.jp/grout/ [in Japanese]) for registered users to obtain and provide data of grout technology. Furthermore, the GDB can be used to correlate requirements of mechanical, physical, and/or chemical properties of a grout material to specifically address concerns over safety assessment, material and injection method development, and/or prediction of grout penetration.  相似文献   
54.
A new subscriber communication system and its design philosophy are described. In addition to telephone communication, the system is simultaneously able to offer data communication, still picture communication, etc. The system is composed of a packetized voice/data terminal, a multi-service switching equipment and the digital subscriber loop connecting between them. The system utilizes the existing subscriber line efficiently and is entirely suitable for coming telephone and data public digital network. 64 kbit/s PCM coded voice conversation and 48 kbit/s data communication were achieved simultaneously over 96 kbit/s digital subscriber line which was spanned up to 2 km.  相似文献   
55.
Free amino nitrogen (FAN) and other low‐molecular‐weight nitrogen compounds (LNC) are highly important as nutrients for yeast. Many different types of low‐malt beer exist around the world, some of which are produced with barley as an adjunct. In these cases, inhibitors contained in barley are known to influence the amount of LNC in wort. Accordingly, it is important to investigate which proteinase class is key in producing these compounds. By investigating the relationship between the FAN contained in wort produced from malt and barley (barley adjunct wort) and malt proteinase activity, it was found that cysteine proteinase and 1,10‐orthophenanthroline (O‐Phen)‐inhibitable metallo proteinases had a significant correlation to the barley adjunct wort FAN levels. In addition, the relationship between malting conditions and these proteinase activities was investigated and the conditions defined for maximal production of proteinases as follows: steeping degree, 50%; germination temperature, 12°C; germination days, 6 days; water spray, 3 times and concentration of gibberellic acid, 10 mg/kg (barley).  相似文献   
56.
Abstract— The Gyricon display consists of hemispherical black and white (bichromal) balls contained in individual liquid-filled cavities and disposed to orient in an electrical field. This bistable reflective light display currently has a diffuse reflectance of more than 18% and a contrast ratio of more than 6:1. The viewing angle approaches that of paper. A new method of fabricating the bichromal balls has enabled practical realization of large-area high-quality displays.  相似文献   
57.
A novel cytokine termed osteoclastogenesis inhibitory factor (OCIF) was purified to homogeneity from conditioned medium of human embryonic lung fibroblasts. OCIF is a heparin-binding basic glycoprotein with Mr of 60 kDa for a monomer and 120 kDa for a homodimer. OCIF specifically inhibits osteoclastogenesis in vitro and increases bone mineral density and bone volume in normal rats. The cloning of OCIF cDNA revealed that OCIF is a soluble member of the tumor necrosis factor receptor (TNFR) superfamily consisting of four cystein-rich domains, two death domain homologous regions (DDHs), and C-terminal basic domain. Mutational analysis of OCIF revealed that N-terminal portion of OCIF consisting of four cystein-rich domains is sufficient to inhibit osteoclastogenesis. OCIF inhibits osteoclastogenesis by binding to the sites expressed on osteoblastic cells and interrupting cell-to-cell signaling between osteoblastic cells and osteoclast progenitors.  相似文献   
58.
Tunable light source using a liquid-crystal Fabry-Perot interferometer   总被引:2,自引:0,他引:2  
A tunable light source with a liquid-crystal Fabry-Perot interferometer (LC-FPI) tuning element that emits a laser beam with a tuning range of 41 nm has been constructed. Incorporating a multiple quantum well (MQW) laser diode with a phase control (PC) section enables the selection of almost all external modes. Stable single-mode emission is obtained for the region, except where the slope of the lasing wavelength versus applied voltage to the liquid crystal is quite large.<>  相似文献   
59.
To clarify the feasibility of introducing solar total energy system into various factories, an experimental facility was constructed at Tsukuba Second Research Center on March 1982. Long-term experimental studies are presently being continued to determine the operating characteristic of the facility. This facility is constructed to improve the system availability and to collect effectively solar energy under fairly bad weather conditions as experienced in Japan. To accomplish this purpose, it is operated by selecting one of three operating modes according to the intensity of insolation and the thermal condition of the heat storage unit. In this paper, the outline of the facility is described. Experimental results show that in this facility the operating rate increases and useful energy, such as electricity, can be obtained from solar energy if the operating mode is selected according to the weather condition at 8:00 a.m.  相似文献   
60.
Membrane proteins play important roles in biological functions, with accompanying allosteric structure changes. Understanding intramolecular dynamics helps elucidate catalytic mechanisms and develop new drugs. In contrast to the various technologies for structural analysis, methods for analyzing intramolecular dynamics are limited. Single-molecule measurements using optical microscopy have been widely used for kinetic analysis. Recently, improvements in detectors and image analysis technology have made it possible to use single-molecule determination methods using X-rays and electron beams, such as diffracted X-ray tracking (DXT), X-ray free electron laser (XFEL) imaging, and cryo-electron microscopy (cryo-EM). High-speed atomic force microscopy (HS-AFM) is a scanning probe microscope that can capture the structural dynamics of biomolecules in real time at the single-molecule level. Time-resolved techniques also facilitate an understanding of real-time intramolecular processes during chemical reactions. In this review, recent advances in membrane protein dynamics visualization techniques were presented.  相似文献   
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