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991.
992.
通过分析水利枢纽的特点,从控制结构和功能结构的角度提出了水利枢纽计算机集成制造系统(CIMS)的体系结构,探讨了水利枢纽CIMS的实现策略,并给出某水利枢纽CIMS的具体实施方案。 相似文献
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IH Skrypal' 《Canadian Metallurgical Quarterly》1997,59(6):63-74
The state and prospects of research on creation of antiadhesins--new generation drugs for preventing and treatment of infectious diseases, are analyzed in the paper. The elaboration of such drugs is based on the profound knowledge about the nature of viral, bacterial, fungal and other infectious agents of diseases, molecular mechanisms of their interactions with the affected organs and tissues which are based on the processes of carbohydrate-protein recognizing. Rapid development of such fields of science as glycobiology and lectinology has created the preconditions for artificial synthesis of oligosaccharides which mimicked the receptors and can interact with adhesive structures of the disease agents more intensively than their natural analogs and block them. This makes the interaction of the latter with the affected organs impossible. The intensive work on elaboration of natural drugs: antiadhesins, is carried out in most countries. Adhesins are not harmful for people and cannot provoke the development of resistance to them in the disease agents. Till recently Ukraine belonged to the number of countries where the fields of science mentioned above were intensively developed but, in connection with the present stagnation of science and even the artificial hindering of its development, the country gradually losses the position of a leader. Hence, one can conclude that when 10-15 years later the market of pharmaceutical products will be filled with antiadhesins, our country will not be on the list of their producers, if the authorities will spend funds to buy foreign drugs as before instead of stimulating the development and production of the home ones. 相似文献
996.
CL Vandewalle MI Coeckelberghs IH De Leeuw MV Du Caju FC Schuit DG Pipeleers FK Gorus 《Canadian Metallurgical Quarterly》1997,20(10):1556-1561
OBJECTIVE: To compare the incidence rate of IDDM in the age-groups 0-14 and 15-39 years in Antwerp, Belgium, and to compare demographic, clinical, and biological data from Antwerp IDDM patients with 92% ascertainment with those from a larger Belgian patient group with 40% ascertainment. RESEARCH DESIGN AND METHODS: Incident cases of IDDM were reported by physicians of the Belgian Diabetes Registry and in Antwerp by several other sources. In Antwerp, completeness of ascertainment was calculated by the capture-recapture method. Demographic and clinical data were collected by questionnaire. Blood was sampled for HLA-DQ genotyping and, in new-inset patients, for autoantibodies. RESULTS: In Antwerp, the age- and sex-standardized IDDM incidence rates were similar in both age-groups (0-14 years: 11.8/100,000; 15-39 years: 8.9/100,000). The incidence rate decreased in girls above age 15 years (6.9/100,000; P = 0.003) but not in boys (11.0/100,000). Both in Antwerp and Belgium, IDDM was diagnosed more frequently in the 15-39 years age-group (60% of all cases) than under age 15 years, with a lower prevalence of acute symptoms, ketonuria, high-risk HLA-DQ genotype, and autoantibodies against insulin, islet cells, and IA-2, but with a higher prevalence of GAD65 autoantibodies. CONCLUSIONS: In Antwerp, the incidence rate of IDDM under age 15 years is intermediately high compared with the rates in other European regions. It is similar in the 15-39 years age-group, but with a marked male predominance. Demographic, clinical, and biological data show the same age-dependent heterogeneity as the data collected nationwide, with 40% ascertainment indicating the representativeness of the latter. 相似文献
997.
Energy transfer in LHCII monomers at 77K studied by sub-picosecond transient absorption spectroscopy
FJ Kleima CC Gradinaru F Calkoen IH van Stokkum R van Grondelle H van Amerongen 《Canadian Metallurgical Quarterly》1997,36(49):15262-15268
Energy transfer from chlorophyll b (Chl b) to chlorophyll a (Chl a) in monomeric preparations of light-harvesting complex II (LHCII) from spinach was studied at 77 K using pump-probe experiments. Sub-picosecond excitation pulses centered at 650 nm were used to excite preferentially Chl b and difference absorption spectra were detected from 630 to 700 nm. Two distinct Chl b to Chl a transfer times, approximately 200 fs and 3 ps, were found. A clearly distinguishable energy transfer process between Chl a molecules occurred with a time constant of 18 ps. The LHCII monomer data are compared to previously obtained LHCII trimer data, and both data sets are fitted simultaneously using a global analysis fitting routine. Both sets could be described with the following time constants: 140 fs, 600 fs, 8 ps, 20 ps, and 2.9 ns. In both monomers and trimers 50% of the Chl b to Chl a transfer is ultrafast (<200 fs). However, for monomers this transfer occurs to Chl a molecules that absorb significantly more toward shorter wavelengths than for trimers. Part of the transfer from Chl b to Chl a that occurs with a time constant of 600 fs in trimers is slowed down to several picoseconds in monomers. However, it is argued that observed differences between monomers and trimers should be ascribed to the loss of some Chl a upon monomerization or a shift of the absorption maximum of one or several Chl a molecules. It is concluded that Chl b to Chl a transfer occurs only within monomeric subunits of the trimers and not between different subunits. 相似文献
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炸药的性能及其在爆破中的作用 总被引:1,自引:0,他引:1
文章探讨了炸药的主要性能及其在爆破中的作用,为爆破作业选择合适的提供了参考依据。 相似文献
1000.
射流泵内不可压流动N—S耦合方程有限元分析 总被引:3,自引:0,他引:3
应用Galerkin有限元和Baldwin-Lomax湍流模型,求解射流泵内不可压粘性流动N-5耦合方程,得到了射流泵内部流动参数分布,给出两个计算实例,计算结果与滓测资料基本吻俣,从而为射流泵内部流场的数值模拟研究提供了一种新方法。 相似文献