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61.
范永亮.转移概率流图的概率理论基础与应用方法(Ⅱ).数理统计与管理,1998,17(2),53~59.本文引入转移概率流图的概念,结合连续抽样方案中的有关问题,计论转移概率流图的分解与浓缩方法 相似文献
62.
Lidar (Light detection and ranging) has special capabilities for remote sensing of many different behaviours of the atmosphere. One of the techniques which show a great deal of promise for several applications is Raman scattering. The detecting capability, including maximum operation range and minimum detectable gas concentration is one of the most significant parameters for lidar remote sensing of pollutants. In this paper, based on the new method for evaluating the capabilities of a Raman lidar system, we present an evaluation of detecting capability of Raman lidar for monitoring atmospheric CO2 in Hefei. Numerical simulations about the influence of atmospheric conditions on lidar detecting capability were carried out, and a conclusion can be drawn that the maximum difference of the operation ranges caused by the weather conditions alone can reach about 0.4 to 0.5km with a measuring precision within 30ppmv. The range of minimum detectable concentration caused by the weather conditions alone can reach about 20 to 35 ppmv in vertical direction for 20000 shots at a distance of 1 km on the assumption that other parameters are kept constant. The other corresponding parameters under different conditions are also given. The capability of Raman lidar operated in vertical direction was found to be superior to that operated in horizontal direction. During practical measurement with the Raman lidar whose hardware components were fixed, aerosol scattering extinction effect would be a significant factor that influenced the capability of Raman lidar. This work may be a valuable reference for lidar system designing, measurement accuracy improving and data processing. 相似文献
63.
建立了模拟Pd-Ag合金膜电解浓缩氚的过程和诸多电解参数的动力学模型。采用求解数学扩散方程的方法得到理论值,并与文献报道的实验数据进行比较。计算结果表明:氚在Pd-Ag膜上的吸附、解吸、浓缩等行为受到诸多条件的制约。在保证密封性能的前提下,对Pd-Ag膜电解槽体的要求是至少应包括有含氚水路循环、阳极气体消除和阴极扩散后氚再生3个组成部分,采取相匹配的级联技术可以提高分离效果;对电解参数的要求是采取尽可能高的电解液温度和稳定的OH-浓度,合适的电流密度,合理的膜厚度、表面特征和Pd黑结合紧密。 相似文献
64.
LI Quan-min OUYANG Rui-zhuo ZHU Gui-fen LIU Guo-guang 《高等学校化学研究》2005,21(5):622-625
Molybdenum( Ⅵ ) is a biologically essential trace element and its role in an extremely wide variety of systems has been reported. Most common methods often fail to determine trace Mo ( Ⅵ ) in the analysis of molybdenum-containing samples, due to limitations such as inadequate detection limits and matrix interference, which make the direct determinations impossible. To solve this problem, various approaches are employed to concentrate and separate Mo( Ⅵ ) to detectable levels. Concentration and separation methods play a main role in the analysis of trace Mo(Ⅵ). Therefore, many separation and preconcentration procedures have been developed for the determination of Mo ( Ⅵ ). 相似文献
65.
Consequent entanglement concentration of a less-entangled electronic cluster state with controlled-not gates 下载免费PDF全文
We present a highly efficient entanglement concentration protocol (ECP) for a four-electron system in a less-entangled cluster state. In this ECP, we only require one pair of less-entangled electron cluster states and one ancillary electron to complete the task. With the help of the controlled-not (CNOT) gate, the concentrated maximally entangled state can be retained for further application with some success probability. On the other hand, the discarded items can be reused to obtain a high success probability. All the features make this ECP useful in the current quantum information field. 相似文献
66.
利用线性光学元器件对光场量子态进行操纵,可以实现远程的量子纠缠调控和量子通讯.通过分析光学分束器对相干态光场的作用,发现当初始光场态是两个两部分纠缠态的直乘时,让其中的两模通过光学分束器作用后再对其进行光子计数,另外两模将会塌缩到新的纠缠态.基于这个特点,提出了一个实现部分纠缠相干态纠缠浓缩的方案.在这个方案中,两个部分纠缠相干态被用来作为量子信道,通过光学分束器作用后对光场进行光子数探测时,如果测量到光场的两模分别处于奇光子数态和零光子数态,则光场另外的两模将塌缩到最大纠缠态,从而完成纠缠浓缩的过程.计算结果表明,对于纠缠相干态,无论其初始的纠缠是多么微弱,利用这种方法总有一定的几率可以从中提纯出最大纠缠态. 相似文献
67.
68.
针对化妆品常用的3种配方体系结构类型(水包油、油包水、水剂),探索了一套适用于化妆品中红景天苷含量测试前处理方法。使用甲醇分散化妆品样品,超声辅助破乳,正己烷萃取分离油脂后,加入大分子沉淀剂,离心并收集清液,浓缩定容,使用配备DAD(二极管阵列)检测器的HPLC进行含量测定。以红景天苷为目标物,加标回收率和检出限分别为,水包油基体为95.3%~99.0%,0.10μg/g和油包水基体为94.4%~101.7%和0.10μg/g,水剂为97.0%~100.8%和0.10μg/g。 相似文献
69.
应用当归药材HPLC指纹图谱技术并结合共有峰相似度、主成分分析(PCA)、聚类分析(HCA)等化学计量学手段,对部分市售当归单味药成方制剂——浓缩当归丸和当归片进行了质量一致性和稳定性,以及与当归药材相关性的初步评价。研究结果表明,浓缩当归丸与当归片之间因制备工艺不同,其化学物质的组成与含量具有明显的差异;不同厂家生产的同类药品具有比较一致的整体色谱形貌,浓缩当归丸与当归药材图谱的相似度略高于当归片,当归片的质量稳定性和一致性略优于浓缩当归丸;同厂家不同批次同种药品的质量差异较小。此外,通过浓缩当归丸和当归片与当归药材色谱指纹图谱的对比分析,进一步探究了当归药材色谱指纹图谱中可能的药效物质信息。 相似文献
70.
Gongming WEI 《数学年刊B辑(英文版)》2008,29(3):247-264
A 2-coupled nonlinear Schrbdinger equations with bounded varying potentials and strongly attractive interactions is considered. When the attractive interaction is strong enough, the existence of a ground state for sufficiently small Planck constant is proved. As the Planck constant approaches zero, it is proved that one of the components concentrates at a minimum point of the ground state energy function which is defined in Section 4. 相似文献