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排序方式: 共有9298条查询结果,搜索用时 31 毫秒
991.
992.
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
993.
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
994.
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
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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
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Ana M. Martínez-Rodríguez Jerrold H. May Luis G. Vargas 《Mathematical and Computer Modelling》2008,48(7-8):1265-1278
Bayesian networks model conditional dependencies among the domain variables, and provide a way to deduce their interrelationships as well as a method for the classification of new instances. One of the most challenging problems in using Bayesian networks, in the absence of a domain expert who can dictate the model, is inducing the structure of the network from a large, multivariate data set. We propose a new methodology for the design of the structure of a Bayesian network based on concepts of graph theory and nonlinear integer optimization techniques. 相似文献