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排序方式: 共有9324条查询结果,搜索用时 15 毫秒
981.
YUAN Tao FENG Kaiming 《核工业西南物理研究院年报(英文版)》2005,(1):95-97
The helium cooled solid breeder blanket that represents the main stream in relevant blanket concepts. It is considered as one of the main options for the fusion reactor. This concept have advantage as follows: ( 1 ) structure simpleness and stability, ( 2 ) no effect of MHD, ( 3 ) a good compatibility in different materials. 相似文献
982.
为了研究平板型太阳热水器板芯表面的高温耐久性,结合国外的实验方法及国内的应用特点设计了本实验方法.该方法以板芯表面光学性能的衰减来推断系统的寿命,即在一定的高温实验条件下模拟加速衰减过程,以板芯表面光学性能衰减小于5%作为判断板芯合格标准. 相似文献
983.
984.
G. Srinubabu K. Jaganbabu B. Sudharani K. Venugopal G. Girizasankar J. V. L. N. S. Rao 《Chromatographia》2006,64(1-2):95-100
A rapid and sensitive RP-HPLC method with UV detection for routine control of pramipexole in tablets was developed. Chromatography
was performed with mobile phase containing a mixture of acetonitrile/phosphate buffer (60/40; v/v) with a flow rate of 0.8
mL min−1. Quantitation was accomplished with the internal standard method; the procedure was validated by linearity (correlation coefficient
= 0.99892), accuracy, robustness and intermediate precision. Limit of quantitation and limit of detection were found to be
4.5 μg and 1.4 μg respectively, which indicates the method is highly sensitive. Experimental design was used during validation
to calculate method robustness and intermediate precision, for robustness test three factors were considered; percentage v/v of acetonitrile, flow rate and pH; an increase in the flow rate results in a decrease of concentration found of the drug,
while the percentage of organic modifier and temperature have no important effect on the response. For intermediate precision
measure the considered variables were: analyst, equipment, days and obtained RSD value (0.56%, n=24) which indicated a good precision of the analytical method. The method was found to be applicable for determination of
the drug in tablet formulations and the results of the developed method were compared with those of the UV spectrophotometric
method to access the active pramipexole content.
Revised: 13 March and 25 April 2006 相似文献
985.
投影寻踪回归在试验设计分析中的应用研究 总被引:12,自引:0,他引:12
本文对三个应用实例进行分析,研究结果表明:PPR方法是试验设计回归分析行之有效的方法,它给技术工作者提供了一个处理试验数据的崭新统计方法。PPR的应用,将会大幅度降低试验费用,提高试验研究工作效率。 相似文献
986.
We consider the survivable network design problem — the problem of designing, at minimum cost, a network with edge-connectivity requirements. As special cases, this problem encompasses the Steiner tree problem, the traveling salesman problem and thek-edge-connected network design problem. We establish a property, referred to as the parsimonious property, of the linear programming (LP) relaxation of a classical formulation for the problem. The parsimonious property has numerous consequences. For example, we derive various structural properties of these LP relaxations, we present some algorithmic improvements and we perform tight worst-case analyses of two heuristics for the survivable network design problem.The research of both authors was partially supported by the National Science Foundation under grant ECS-8717970 and the Leaders for manufacturing program at MIT. 相似文献
987.
988.
989.
Dmitriy Alexeev Robert L. Baxter Dominic J. Campopiano Robin S. McAlpine Lisa McIver Lindsay Sawyer 《Tetrahedron》1998,54(52):2583-15898
Modelling of the H-bonding interactions involved in the binding of the adenine base component of ATP to E. coli dethiobiotin synthetase (DTBS) suggested that 6-hydroxypyrimidin-4(3H)-one (6-HP4) should selectively bind to this site in the enzyme. Kinetic studies show that 6-HP4 is a competitive inhibitor of DTBS and x-ray crystallography shows that 6-HP4 binds specifically in the purine base binding site of the enzyme. 相似文献
990.