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911.
曾祥基 《成都大学学报(自然科学版)》1998,(3)
研究了心衰病人口服小蘖硷后的吸收性,血浆样品用甲醇预处理以沉淀其蛋白质,小蘖硷测定条件为:μBondapakC18柱(10μm,300×3.9mmi.d.)乙腈和0.02mol/L磷酸混合液(45:55.v/v)为流动相,紫外鉴定器设定在波长为346nm处,进样量为50μl时,最小检测极限为8ng/ml。小蘖硷平均回收率为92.5%,结果表明本试验建立的方法和血浆中黄连素浓度监测有利于指导治疗心衰。 相似文献
912.
Alexey B. Petrovsky 《系统科学与系统工程学报(英文版)》2007,16(1):22-33
There are many practical decision problems where decision makers' preferences may be inconsistent and contradictory. In this paper, new methods for ordering and classifying multi-attribute objects by discordant collective preferences are suggested. These methods are based on the theory of multiset metric spaces. The proposed techniques are applied to ranking companies and a competitive selection of projects, which are estimated by several experts upon multiple qualitative criteria. 相似文献
913.
本文为高性能液相色谱作定量分析,提供一种新颍方法,自动求得峰形分离良好的色谱图,并由此对于仪表之智能化前景作一展望。利用多段梯度洗脱法来改进分离,会引起搜索该条件之复杂化。为此,启发微机来搜索满意的分离条件,而不去搜索最优分离条件,较为合理而且方便。用本法分析人体血液中21种主要氨基酸组分,获得成功。 相似文献
914.
In a hemodialysis process, the blood that runs through straight channels exchanges substances with the dialysate through a semi-permeable membrane. The waste products, such as urea and creatinine, are therefore removed from the plasma by the membrane. In the analysis of this process, determination of the ultra-filtration profile along the porous membrane surface remains a difficult problem. In this work, an analytical solution to the derivation of such a profile was detailed, and the feasibility of this solution was discussed. The ultra-filtration profile was found to be in a cosine shape. 相似文献
915.
YUN Jianping YANG Xudong XIE Tiebang CHANG Suping 《武汉大学学报:自然科学英文版》2007,12(6):1066-1072
A novel hybrid instrument of contact and non-contact measurement with large range is developed, and both measurement systems are based on a Linnik interference microscope and on white-light interference measuring techniques. The ambiguity presented in conventional monochromatic interferometers is not present in the contact and non-contact measurement, and they have a virtually unlimited unambiguous range. For the contact measurement, the vertical measuring range is ±5 mm with a resolution of 1 nm and the horizontal measuring range is ±25 mm in x-range and y-range with a resolution of 1.25 μm; for the non-contact measurement, the vertical measuring range is ~5 mm with a resolution of 1 nm and the horizontal resolution better than 0.5 urn. 相似文献
916.
GAN Shixin QIU Dehua 《武汉大学学报:自然科学英文版》2007,12(6):971-974
In this paper we give an elementary and unified proof of the Hajek-Renyi inequality, and get a general version of this inequality which not only covers the all known results but also derives some new results. 相似文献
917.
This paper presents a methodology which determines the allocation of power demand among the committed generating units while minimizes number of objectives as well as meets physical and technological system constraints. The procedure considers two decoupled problems based upon the dependency of their goals on either active power or reactive power generation. Both the problems have been solved sequentially to achieve optimal allocation of active and reactive power generation while minimizes operating cost, gaseous pollutants emission objectives and active power transmission loss with consideration of system operating constraints along with generators prohibited operating zones and transmission line flow limits. The active and reactive power line flows are obtained with the help of generalized generation shift distribution factors (GGDF) and generalized Z-bus distribution factors (GZBDF), respectively. First problem is solved in multi-objective framework in which the best weights assigned to objectives are determined while employing weighting method and in second problem, active power loss of the system is minimized subject to system constraints. The validity of the proposed method is demonstrated on 30-bus IEEE power system. 相似文献
918.
A physically based empirical model was established for the beginning and ending dates (BED) of limited temperatures.Data used were daily mean temperatures from 34 conventional stations in the Chongqing region,measured from 1961 to 2000.Using this model in combination with the distributed modeling results of monthly mean temperatures,we developed a method for creating a distributed simulation of the BED and durations of limited temperatures in the rugged terrain of Chongqing.Spatial distribution maps were generated at a resolution of 100×100 m for the BED and durations of the limited temperatures of 0,10,15 and 20.Simulations suggest that the distributed model is able to successfully reveal the macroscopic trends and local distributions.For the modeled BED,the mean absolute bias error is 0.6-2.4 d.Cross-validation and case-year tests show mean absolute bias errors of 1.3-2.8 d and 0.7-2.5 d,respectively.Comparison shows that the simulation results are consistent with the field investigations.This implies that the simulations are as good as observations,thus providing a viable technique for simulating mountainous heat resources using conventional meteorological data. 相似文献
919.
Alexander V. Zhdanov Ruslan I. Dmitriev Dmitri B. Papkovsky 《Cellular and molecular life sciences : CMLS》2011,68(5):903-917
Bafilomycin A1 (Baf) induces an elevation of cytosolic Ca2+ and acidification in neuronal cells via inhibition of the V-ATPase. Also, Baf uncouples mitochondria in differentiated PC12
(dPC12), dSH-SY5Y cells and cerebellar granule neurons, and markedly elevates their respiration. This respiratory response in dPC12 is accompanied by morphological changes in the mitochondria and decreases the mitochondrial pH, Ca2+ and ΔΨm. The response to Baf is regulated by cytosolic Ca2+ fluxes from the endoplasmic reticulum. Inhibition of permeability transition pore opening increases the depolarizing effect
of Baf on the ΔΨm. Baf induces stochastic flickering of the ΔΨm with a period of 20 ± 10 s. Under conditions of suppressed
ATP production by glycolysis, oxidative phosphorylation impaired by Baf does not provide cells with sufficient ATP levels.
Cells treated with Baf become more susceptible to excitation with KCl. Such mitochondrial uncoupling may play a role in a
number of (patho)physiological conditions induced by Baf. 相似文献
920.
通过考察我国铁路勘测设计技术现状和存在的问题,分析地理信息系统(GIS)与铁路勘测设计的关系,提出了基于WebGIS的铁路勘测设计一体化解决方案,讨论了基于WebGIS的铁路勘测设计系统的体系结构、应用前景和对铁路勘测设计的影响. 相似文献