一类特殊二维0-1规划的广义指派模型求解

二维0-1整数规划模型应用广泛,对广义指派问题的研究,解决了一些二维0-1整数规划问题.但有些实际问题具有特殊上限约束,目前还没有对应的方法.针对该实际情形,本文建立了相应的数学模型,利用对指派模型的推广,求得问题最优解,从理论上解决了这一类特殊约束二维0-1整数规划的最优解求取问题.并通过算例说明了方法的使用.     

人力资源多维分配问题的混合算法

针对已有多维分配问题求解算法复杂、耗时长及精度低等问题,本文将二部图中寻求最优匹配的方法进行推广,运用试分配、饱和路调整和增广路调整对多维分配问题的最优解进行搜索,提出了求解人力资源多维分配问题的最小零面优先分配混合算法和随机试分配混合算法,对算法的有效性进行了理论证明,并分析了算法的时间和空间复杂度;同时通过这两种混合算法对初始零元素数不同的代价矩阵求解时间的计算,以及与Lagrangian松弛算法和剪枝法的耗时、精度的对比,分别得到了两种混合算法的适用性和高效性,最后通过算例验证了算法的有效性。     

求解指派问题的一个算法

为了便于建立与指派问题有关的决策支持系统，本给出了一个求解指派问题的数值算法，证明了算法的理论依据。该算法能求得问题的最优解，并具有易于编程实现、收敛性好等优点，大量数值实验表明该算法非常实用有效。     

分派问题的灵敏度分析及其应用

讨论分派问题的效率矩阵的元素发生变化时,对最优解的影响;在保持分派问题最优解不变的情况下,效率矩阵的元素的变化范围;及当分派问题的最优解发生变化后,如何用简单的方法求得新的最优解等.     

杀菌剂环氟菌胺波谱学数据全归属

环氟菌胺是一种具有新型母核结构的优秀杀菌剂,该文采用~1H NMR、~(13)C NMR、~(19)F NMR、~1H-~(13)C HSQC、~1H-~(13)C HMBC和~1H-~(15)N HMBC等多种核磁共振(NMR)技术,并结合质谱(MS)、紫外光谱(UV)和红外光谱(IR)等方法对环氟菌胺进行了解析,同时对一维核磁共振(1D NMR)波谱数据进行全归属,讨论了UV和IR的吸收峰与该化合物各官能团的对应关系、~(19)F对其~1H和~(13)C NMR谱峰的影响,以及MS主要离子碎片的归属和化合物裂解规律.     

一个含苯并咪唑环的酰氨基硫脲NMR研究

该文合成了一个新的在医药方面具有潜在应用价值的含苯并咪唑环的酰氨基硫脲化合物,即4-(4-甲氧基苯基)-1-[2-(4-硝基苯氧基甲基)-苯并咪唑-1-基\]甲酰基氨基硫脲,并利用元素分析、IR和NMR对其结构进行了表征. 通过NOESY谱确定了其两种异构体(A和B)的构型,并利用2D NMR技术对它们的¹H NMR 和¹³C NMR谱进行了全归属,给出了相应的偶合常数和两种异构体的含量.     

New NIST sediment SRM for inorganic analysis

NIST maintains a portfolio of more than 1300 standard reference materials (SRM), more than a third of these relating to measurements in the biological and environmental fields. As part of the continuous renewal and replacement efforts, a set of new marine sediments has been recently developed covering organic and inorganic determinations. This paper describes the steps taken in sample preparation, homogeneity assay, and analytical characterization and certification with specific emphasis on SRM 2702 inorganics in marine sediment. Neutron activation analysis showed the SRM to be highly homogeneous, opening the possibility for use with solid sampling techniques. The certificate provides certified mass fraction values for 25 elements, reference values for eight elements, and information values for 11 elements, covering most of the priority pollutants with small uncertainties of only several percent relative. The values were obtained by combining results from different laboratories and techniques using a Bayesian statistical model. An intercomparison carried out in field laboratories with the material before certification illustrates a high commutability of this SRM.Electronic Supplementary Material Supplementary material is available in the online version of this article at     

NMR spectral assignment of 2α- and 3β-methylhopanes and evidence for boat conformation in D ring of 17α(H),21α(H)-hopanes

The full (1)H and (13)C NMR chemical shift assignment of 2α-methyl-17α(H),21β(H)-hopane is presented. This compound is formed in mature sediments from biogenic sources of 2β-methyl-17β(H),21β(H)-hopanoids, which include several cyanobacteria. In addition, full (1)H and (13)C NMR chemical shift data of all four 17,21 isomers of 3β-methylhopane have been assigned. The thermodynamically most stable 3β-configuration corresponds to that found in bacterial sources. The data presented here suggest minor corrections to the (13)C chemical assignments reported earlier for 17α(H)-hopanes. Moreover, spectral evidence indicates an unexpected ring-D boat conformation of 17α(H),21α(H)-hopanes, which may serve to explain the steric strain reported for this isomer.     

原位实时近红外光谱研究核壳乳液聚合过程

将苯乙烯(St)和丙烯酸丁酯(BA)单体以不同的聚合方式制备核壳乳液和共聚乳液, 并采用近红外光谱技术实现了对乳液反应过程的原位实时监测, 通过对近红外光谱的谱带归属和主成分分析, 为近红外光谱技术判别乳液聚合过程提供了科学依据, 也为判断反向核壳乳液核壳翻转的拐点提出了一种新的方法. 采用簇类独立软模式法(SIMCA)建立了定性判别模型, 得到了很好的判别结果, 为进一步研究近红外光谱技术用于核壳乳液聚合过程奠定了基础.     

Analysis of the hyperfine structures and A doubling of high-resolution LMR spectra of ~(15)N~(16)O (X~2Π)

From the theories of the nuclear hyperfine structure (HFS) and A doubling of diatomic molecules, several brief algebraic equations for interpretation of HFS and A doubling of transitions of diatomic molecule have been developed. A few important parameters of HFS and A doubling of 15N16O have been efficiently and accurately obtained from the analysis of the high resolution spectra of 15N16O (X2Π) observed in our experiments with these equations. This method can provide an effective approach to obtain important hyperfine parameters of novel radicals from their high resolution laser magnetic resonance spectra.