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排序方式: 共有1627条查询结果,搜索用时 15 毫秒
201.
The development of a machine translation system is one of the most difficult computational tasks. Without a deep semantic analysis of both source and target languages, a machine translation system can not generate good results. This paper describes a machine translation system based on a new method called the Integral Method in which semantic analysis using an active dictionary plays a very important role. 相似文献
202.
Masaji Matsuda Chiyoshi Kamizawa Hitoshi Masuda Takashi Nakane Noriaki Sato 《Desalination》1979,29(3):275-284
Taking note of the affinity of some reverse osmosis membranes to Au(CN)-2 in the citrate buffered gold plating rinse, we accomplished the recovery of gold by the adsorption to some polymers. Among several polymers, tested nylon fibre had the most excellent characteristics of adsorption. The amount of adsorption of gold on nylon fiber increased with a decrease in pH value of the solution, and 7.5 mg of gold was adsorbed on 1 g of nylon fiber at pH 3, 25°C. The rate of adsorption increased with an increase in temperature. In the case of desorption, the solution containing cyanide ions at a pH as high as 10 was desirable to be employed as an eluant. By passing the simulated plating rinse through a column of nylon fiber, the adsorption and desorption of gold was successfully accomplished. The maximum concentration of gold in the eluant was approximately 600 ppm. 相似文献
203.
The polymerization of a series of methacrylic acid esters (methyl, ethyl, isopropyl and n-butyl) with sodium hexanitrocobaltate, Na3[Co(NO2)6] was carried out in a methanol-water mixed solvent. The homogeneity of the polymerization system was dependent on the composition of the mixed solvent and greatly affected the rate of the polymerization. A maximum rate was obtained at approximately equimolar fractions of methanol and water in the polymerization of methyl methacrylate. The effect of bulkiness of ester groups on the polymerizability of each monomer was indistinguishable in the mixed solvent system. Kinetic study of the polymerization of methyl methacrylate in a mixed solvent of about an equimolar fraction of methanol and water gave the following polymerization equation: , and an apparent activation energy of 10.6 kcal/mol. The copolymerization of methyl methacrylate and styrene with the initiator suggested that polymerization proceeded via a radical mechanism. The possibility of a certain interaction between initiator, solvent and monomer in the initial stage of the polymerization is discussed on the basis of the kinetic data, properties of oligomers of methyl methacrylate, spectroscopic and other data. 相似文献
204.
205.
A specially-developed multidisplay system using a 6 inch color CRT, created through actual testing in experimental vehicles, was mass-produced for the Japanese market in January 1985. A year later, the multidisplay system was improved through an addition in the information displayed on the CRT and mounted in the 1986 Toyota Soarer. These improvements are described, and an outline of the multidisplay system and details regarding newly developed technology consequent to its development are also described 相似文献
206.
Hitoshi Takeda 《Energy and Buildings》1979,2(1):9-17
The energy required to heat and to cool an apartment varies according to the aspect and situations of the rooms in the apartment, the mode of air-conditioning (all day or intermittent) and the geographical location of the building it is situated in. A year-round computer simulation has been carried out using hourly meteorological information throughout 1975 in each of seven districts — Sapporo, Akita, Tokyo, Nagoya, Osaka, Kagoshima and Naha. The capacity requirements of the equipment, and the total energy requirement for year-round air-conditioning for a room situated in the centre of the south side, middle floor of a building in Tokyo was calculated as the planning guide, varying the situations and directions. The research continued with the study of air-conditioning load ratios for each district, measured by the degree-day and calorie-day index, so that year-round air-conditioning loads in other districts could be easily obtained. 相似文献
207.
K Saito J Sakurai J Ohata T Kohsaka H Hashimoto K Okumura R Abe M Azuma 《Canadian Metallurgical Quarterly》1998,160(9):4225-4231
The blockade of B7, using B7 antagonists such as anti-CD80 and/or -CD86 mAbs or CTLA4Ig in vivo, has been shown to induce an efficient suppression of T cell-mediated immune responses in allograft, allergy, and autoimmune models. However, this treatment does not result in complete tolerance. In this study, we examined CD28-B7-independent activation pathways in the pathogenesis of graft-vs-host disease (GVHD) using allogeneic T cells from CD28-deficient mice. Acute GVHD was induced in the absence of CD28 on donor T cells and its manifestations were obvious in the lymphoid tissues. The CD28-independent GVHD was significantly improved by treatment with anti-CD40 ligand (CD40L) mAb. In contrast, treatment with anti-CD80 plus anti-CD86 mAbs exacerbated the clinical manifestations of GVHD and increased the T cell response against host alloantigen, resulting in the expression of CTLA4, CD40L, and CD25 on splenic T cells. These data suggested that the CD40L-CD40 pathway significantly contributed to the CD28-independent pathogenesis of acute GVHD, whereas the CTLA4-B7 pathway acted protectively in the development of GVHD. These results imply that selectively blockading CD28, instead of disrupting both CD28 and CTLA4, would be a better therapeutic strategy for GVHD. Additionally, the simultaneous use of CD40 antagonists may be advantageous. 相似文献
208.
M Aoyagi M Yamamoto H Azuma G Nagashima Y Niimi K Hirakawa K Yamamoto 《Canadian Metallurgical Quarterly》1997,107(5):365-370
A case of sinusitis caused by the basidiomycete Schizophyllum commune is reported in a 36-year-old female with a history of allergic rhinitis and dermatitis. The patient presented with sudden nasal obstruction, purulent nasal discharge, headache and general discomfort. Computer tomography revealed extensive opacity of the left maxillary sinus as well as erosion of the nasal wall and maxillary bone. Mycological examinations of nasal discharges and material aspirated during anthrostomy showed hyaline, septate hyphae with rare spicules. Primary isolation yielded a white, woolly mould which demonstrated clamp connections and basidiocarp primordia but these characteristics were lost in subculture. Identification was confirmed by vegetative compatibility studies. The patient was treated with itraconazole to avoid possible postsurgical dissemination. Three months after cessation of therapy, no recurrence of infection had occurred. 相似文献
209.
Effects of the Zn addition to the Cu-Sn matrix of the Nb3Sn composite tape have been investigated by measuring the matrix work-hardening behaviour, the rate of Nb3Sn layer formation and the pertinent superconducting properties. The Zn addition drastically enhances the diffusion rate of Nb3Sn formation at each Sn level in the matrix examined, leading to sufficient superconducting properties even at a low Sn level of 3.5 at. %; a sample containing 3.5 at. % Sn and 15 at. % Zn in the matrix exhibits a critical temperature and critical current density comparable with those of samples at a Sn level of 7 at. %. The upper critical field obtained for a sample with the 6 at. % Cu-6 at. % Sn-4 at. % Zn matrix beyond 200 kOe. The work-hardening of the composite matrix is found to be essentially a function of Sn level, and insensitive to the Zn addition. 相似文献
210.