广西地区273例恶性肿瘤患者血清微量元素检测结果分析

为探讨血清微量元素与恶性肿瘤之间的关系,用化学比色法对273例恶性肿瘤患者和30例正常人血清中的铜、锌、铁、钙进行了检测。结果表明,恶性肿瘤患者血清钢和铜/锌比值明显高于正常人,而锌、铁、钙含量明显低于正常人,均有显著性差异,分别为P<0.001～P<0.05。提示:微量元素与恶性肿瘤的发生、发展密切相关,对恶性肿瘤的诊断、疗效及预后观察有重要价值。     

合金化成分对NiTi合金M_s点影响的正电子湮没研究

用双探头符合系统测量了金属Fe、Co、Ni、Al、Nb、Cu、Ti和NiTi合金的多普勒展宽谱,计算了其S参数和W参数,分析了合金中d-d金属键的作用.结果表明,当用Fe、Co或Al原子加入NiTi合金时,都将使合金中参与形成d-d金属键的d电子减少,从而使金属键减弱;而用Cu或Nb原子加入NiTi合金时,对合金中d-d电子作用的影响很小,合金中共价键的成分变化不大.在NiTi合金中加入合金化元素可以改变其电子结构,进而影响Ms点.     

Investigations on the Angle-Dependent Dip Coating Technique (ADDC) for the Production of Optical Filters

Angle-dependent dip coating (ADDC) is a modified dip coating technique that offers advantages for the production of optical interference filters. In contrast to conventional dip coating (DC), the substrate is withdrawn from the coating solution under an angle of inclination. Thereby, the two surfaces of the substrate are coated with individual film thicknesses. An experimental setup for ADDC has been built and the decisive process influences on coating thicknesses have been evaluated. In order to gain full control over the individual layer thicknesses, reaching from 20 nm to 160 nm, it is necessary to vary the following process parameters: lifting speed, angle of inclination and concentration of the dipping solution. The results of coating experiments prove the advantages of ADDC over DC. A first example aims at reducing the number of coating steps: an ADDC long pass filter produced in 10 coating steps reaches the same optical performance as a conventional DC filter made in 16 steps. A second example demonstrates the possibility to improve quality: a commercial DC beam splitter can be improved with respect to the flatness of transmission and reflection curves when being produced in 4 steps by ADDC instead of 8 steps by DC. Furthermore, ADDC offers the possibility to fabricate even narrow band pass filters, which are naturally difficult to obtain by conventional DC.     

A new homoflavonoid from the seed of Caesalpinia minax Hance

<正>A new homoflavonoid was isolated from the seed of Caesalpinia minax Hance.On the basis of spectral evidences,its structure was established and named as minaxin.     

关于有限群极大子群的强θ-完备

本文定义了有限群极大子群的强θ-完备这一概念．通过研究极大子群的强θ-完备对群结构的影响,给出了有限群可解性,超可解性,幂零性的一些新刻画,所得结果改进了以往的定理．     

扰动的中立型时滞差分方程的一致渐近稳定性

本文研究扰动的一维中立型时滞差分方程△(x(n)-cx(n-k))=f(n,xn)+g(n,xn),n∈Z+的稳定性问题.证明了在某些条件下,无扰动方程△(x(n)-cx(n-k))=f(n,xn),n∈Z+零解的一致渐近稳定性蕴涵着上述扰动方程零解的一致渐近稳定性.本文的结果推广并改进了已有的结果.     

一类矩阵方程的极小Frobenius范数双对称解

利用矩阵的广义奇异值分解,给出了实矩阵方程ATXA=B存在极小Frobenius范数双对称解的充要条件及其解的表达式.     

少数服从多数规则的特性

假定投票人的人数是奇数，E．S．Maskin引入传递性刻画了少数服从多数规则的特性．Campbell和Kelly试图将E．S．Maskin的理论推广到投票人的人数是任意整数的情形，用有限传递性来刻画少数服从多数规则的特性．我们发现存在这样的少数服从多数规则，它满足无关方案独立性条件并且认为任意两个不同的备选方案都是有差异的，但却不一定满足有限传递性．所以，用有限传递性来刻画少数服从多数规则的特性就有一定缺陷．本文对满足无关方案独立性的少数服从多数规则特性进行了重新刻画，并弱化了有关条件．     

怀孕期头发中一些元素含量的变化趋势

用同步辐射激发X射线荧光分析,对11个产妇怀孕期间头发内一些元素含量的变化趋势进行了测量,在各自对比的基础上,得到了一些结果。     

广义二元复合二项风险模型的破产概率

本文研究了索赔过程和保费收取次数均为二项分布的双险种风险模型,得到了其破产概率的一般公式。