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991.
Soluble -conjugated coordination polymers having a ruthenium(II) complex in the main chain were prepared from a soluble metal complex monomer and a bridging ligand via coordination. Refluxing of an ethanol-water suspension containing (4,4-dinonyl-2,2-bipyridyl)Ru(III) with 2,3-bis(2-pyridyl)pyrazine gave the coordination polymer. The resulting polymer was soluble in common organic solvents. The structure was confirmed by uv/vis spectra and gpc analysis.  相似文献   
992.
Manufacturing technology in the field of Large-Scale-Integrated (LSI) circuit production has overcome the problems of enlarged wafer size and increasing level of integration. The market environment of the LSI industry has become more demanding with increased requirements, delivery time and stiffer cost competition. A Computer-Integrated Manufacturing System (CIMS) well-adapted to the unique characteristics of LSI production system is thus urgently needed.

This paper describes the development of CIMS in LSI production systems, and presents the example of a DTS (Diffusion Total System), constructed in a real LSI wafer fabrication factory. Features of DTS are (a) on-line real-time manufacturing data acquisition and monitoring through a production information network, (b) automatic control of process equipment, (c) shop floor control for computer aided decision support at the shop floor level, and (d) data analysis and reporting derived from a large amount of accumulated data. This paper deals with shop floor control, and in particular with a priority control system unique to the LSI wafer fabrication line.  相似文献   

993.
Cytochrome c oxidase   总被引:1,自引:0,他引:1  
  相似文献   
994.
The brain-gut hormones, gastrin and cholecystokinin, have a trophic effect on the gastrointestinal mucosa in vivo and promote the growth of several neoplastic cell lines. In this study, cholecystokinin-B/gastrin receptor has been demonstrated to provide a novel molecular marker for the diagnosis of small cell lung cancer by using biopsy specimens. Physiological expression of the receptor mRNA is detectable in particular areas of the human brain, stomach, and pancreas but not in the lung. The receptor mRNA was detected selectively in all small cell lung cancer (10 cases) with a RT-PCR assay. By contrast, it was detectable in only 1 of 13 squamous cell carcinomas or 21 adenocarcinomas of the lung. Thus, the cholecystokinin-B/gastrin receptor could be an attractive therapeutic target for small cell lung cancer.  相似文献   
995.
The effect of interstimulus interval on nerve responses and subjective sensory ratings evoked by thermal stimulation of the teeth were studied in man. A total of 30 unitary discharges during heat stimulation of the lower incisor teeth were recorded from the inferior alveolar nerves using microneurographic technique. Fifteen of them had threshold sensory ratings above 3 (pain related-units) and 15 had ratings of less than 2 (non-pain-related units). Repetitive heat stimulation was applied to the teeth with interstimulus intervals of 180 s (ISI 180) and 30 s (ISI 30). Repetitive (ISI 180 and ISI 30) non-painful heat stimulation of the teeth did not alter either the intensity ratings or unitary discharge activities of non-pain-related units (P > 0.05). Repetitive painful heat stimulation of the teeth with ISI 180 did not alter the intensity ratings of pain-related units (P > 0.05), whereas that with ISI 30 significantly reduced the intensity ratings of pain-related units during a second session of heat trials (P < 0.05). On the other hand, repetitive heat stimulation of the teeth with ISI 180 caused a slight reduction in the firing frequency of pain-related units (P > 0.05). Repetitive painful heat stimulation with ISI 30 significantly reduced the firing frequency of pain-related units (P < 0.05).  相似文献   
996.
The effect of two iron catalysts, red mud and CGS S-G, as well as C0-Mo/AI2O3 and Ni-Mo/Al203 commercial catalysts on the composition of oil derived from the liquefaction of Japanese subbituminous coal have been investigated comparatively by conventional autoclave experiments at 440 and 450°C under initial hydrogen pressure of 85kg/cm2 G with tetralin to coal weight ratio of 3. From the results obtained at 450°C, total conversion and the yield of gas revealed almost same level with four catalysts, but the oil product from molybdenum catalysts showed higher yield than that from iron catalysts. CGS S-G catalyst also showed higher yield of oil product than red mud catalyst. Reaction behavior of two iron catalysts were also tested by solvent recycle mode experiments.  相似文献   
997.
A stretchable carbon nanotube strain sensor for human-motion detection   总被引:1,自引:0,他引:1  
Devices made from stretchable electronic materials could be incorporated into clothing or attached directly to the body. Such materials have typically been prepared by engineering conventional rigid materials such as silicon, rather than by developing new materials. Here, we report a class of wearable and stretchable devices fabricated from thin films of aligned single-walled carbon nanotubes. When stretched, the nanotube films fracture into gaps and islands, and bundles bridging the gaps. This mechanism allows the films to act as strain sensors capable of measuring strains up to 280% (50 times more than conventional metal strain gauges), with high durability, fast response and low creep. We assembled the carbon-nanotube sensors on stockings, bandages and gloves to fabricate devices that can detect different types of human motion, including movement, typing, breathing and speech.  相似文献   
998.
Six kinds of regioselectively substituted cellulose heteroesters (cellulose propanoate diacetate, cellulose butanoate diacetate, cellulose acetate dipropanoate, cellulose butanoate dipropanoate, cellulose acetate dibutanoate, and cellulose propanoate dibutanoate) and three kinds of cellulose triesters (cellulose triacetate, cellulose tripropanoate, and cellulose tributanoate) were prepared from a microcrystalline cellulose, and their melting points were measured by differential scanning calorimetry. Based on the results of strong correlationship between the melting point and the length of the acyl groups at the secondary hydroxyl groups at C2 and C3 positions, the latter was identified as playing a decisive role in the thermal properties of the cellulose fatty acid heteroesters. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1511–1515, 1997  相似文献   
999.
A novel technique utilizing the gelation reaction of natural polymers has been proposed for the separation of solid from liquid in difficult-to-filter colloidal suspensions. This technique is especially effective in the treatment of colloidal muddy water of high solid concentration, which is often produced as a byproduct of certain construction processes. Colloidal suspensions are mixed with a sodium alginate solution, and this mixture is added to a calcium chloride solution, resulting in the entrapping of colloidal particles by the calcium alginate gel. Gel suspensions are then drained gravitationally, followed by mechanical expression of gel particles. Fundamental aspects of this process are investigated by using sodium bentonite as an experimental material. The alginate-bentonite mixture is added dropwise to the calcium solution. Decreasing the droplet size of the mixture expedites gelation since the diffusion of calcium ions into droplets determines the rate of gelation reactions. Reducing the alginate content expedites expression of the gel since alginate content is inversely proportional to the rate of expression.  相似文献   
1000.
Summary Formation of an interpenetrating polymer network (IPN) composed of organic polymer gel and silica gel in the form of polymer hybrids was conducted by utilizing the photodimerization of thymine bases. Thymine-modified poly(2-methyl-2-oxazoline) (POZO-T) was synthesized by the condensation reaction of partially hydrolyzed polyoxazoline and 1-(2-carboxyethyl)thymine. Organic-inorganic polymer hybrids were prepared from POZO-T and tetramethoxysilane (TMOS). Transparent and homogeneous polymer hybrids could be obtained. The photodimerization and the reverse reaction of thymine in the polymer hybrids were monitored by the UV absorption spectroscopy. Received: 27 March 2000/Revised version: 5 June 2000/Accepted: 15 June 2000  相似文献   
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