ON J-SELFADJOINT EXTENSION OF THE PRODUCT OF TWO nTH-ORDER J-SYMMETRIC ORDINARY DIFFERENTIAL OPERATORS ON [a,b]

The problem of J-selfadjointness of the product of two nth-order J-symmetric operators on [a,b] is studied. We give a condition to ensure that the product operator is a J-selfadjoint extension.     

Synthesis and characterization of an intermediary of new heat-resistant energetic materials

<正>Nitration of 4,4'-biphenyldicarboxylic acid(BPDC) was studied and an aromatic carboxylic acid containing two nitro groups was synthesized and characterized through elemental analysis and IR spectra.Crystal structure of DNBPDC(DNBPDC=2,2'- dinitro-4,4'-biphenyldicarboxylic acid) was determined by X-ray single crystal diffraction and the thermal decomposition was carried out through DSC and TG-DTG analyses.     

强反射复杂表面随机缺陷检测照明系统分析

分析了采用CCD光电检测法对强反射复杂表面随机缺陷进行检测时的光学照明问题。给出了缺陷显现力的具体定义。对比了平行光和均匀散射光对消除强反射光的不同作用及对不同表面缺陷的显现力。分析了使用均匀散射光作为光源时，工件表面照度对成像质量的影响。给出了在上述条件下光照系统设计的基本原则。     

集值Vitali-Hahn-Saks-Nikodym定理

本文通过强可加集值测度的一个等价叙述引入集值测度一致强可加的概念,并建立了集值测度的Vitali-Hahn-Saks-Nikodym定理.     

表面活性剂增敏2,4-二氯苯基荧光酮分光光度法测定煤中的微量锗

研究了在表面活性剂存在下,锗与2,4二氯苯基荧光酮(2,4DClPF)的显色条件,在18～25mol·L-1硫酸介质中,锗与2,4DClPF、阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)形成有色三元胶束络合物,其最大吸收波长为516nm,表观摩尔吸光系数ε为138×105L·mol-1·cm-1。方法的线性范围为0～125μg·25mL-1,回收率为103%～106%,相对标准偏差为11%～17%。所拟方法用于煤样中微量锗的测定,结果较满意。     

某些二茂铁丙烯酰胺的结构与红外光谱特征

总结归属了6种N-烷基二茂铁丙烯酰胺及13种N-芳基二茂铁丙烯酰胺的主要红外吸收谱带和特征,讨论了其红外吸收频率随化合物结构变化的规律。结果表明,氮上取代基从空间效应及电子效应两方面影响化合物红外吸收,主要是对v c-c,v c-o及酰胺Ⅱ带有较大影响。     

邻菲咯啉荧光猝灭法测定中草药中的微量铁

本文基于铁对邻菲咯啉的荧光具有猝灭的特性 ,拟定了一种测定微量铁的方法。该方法在pH =4 6～ 7 1的 (CH2 ) 6N4 HCl缓冲介质中 ,Fe(Ⅱ )与邻菲咯啉反应生成红色络合物 ,使邻菲咯啉溶液的荧光明显猝灭 ,其激发波长λex=2 6 5nm ,发射波长λem=36 5nm ,铁的浓度在 2 4～ 112ng·mL-1范围内符合比耳定律 ,相关系数为 0 9981,检测限为 4 1ng·mL-1。对于 80ng·mL-1的铁测定 11次的相对标准偏差为 3 2 %。用该方法测定了多种中草药中的微量铁 ,结果满意     

Friedel-Crafts Acylation of Ferrocene Catalyzed by Solid Superacid, Silica-supported Polytrifluoromethanesulfosiloxane

Solid superacid, silica-supported polytrifluoromethanesulfosiloxane (SiO2-Si-SCF3) was firstly used in the Friedel-Crafts acylation of ferrocene as a novel catalyst. IR spectra, WAXD and specific surface area of the superacid SiO2-Si-SCF3 were also investigated.     

Fluorescence turn-on chemosensor for Hg~(2+) based on a rhodamine derivative and its application in bioimaging

A fluorescence turn-on chemosensor based on rhodamine B derivative (FD10) has been developed as a highly sensitive chemosensor for Hg2+. A prominent fluorescence enhancement was measured in the presence of Hg2+, which was in agreement with the changes in the absorption spectrum. Furthermore, by means of laser scanning fluorescence microscopy experiments, it was demonstrated that FD10 was cell-permeable and could be used as a fluorescent probe for monitoring Hg2+ in living cells.     

离子交换分离3,5-二溴水杨基荧光酮-EDTA-CTMAB分光光度法测定微量钍

在EDTA和CTMAB存在下 ,在pH 8 8～ 10 2NH4 Cl NH3 ·H2 O缓冲体系中 ,钍 (Ⅳ )与 3,5 二溴水杨基荧光酮 (3,5 DBSF)形成红紫色多元配合物 ,其最大吸收波长为 5 5 7nm ,表观摩尔吸光系数ε为 2 19× 10 5L·mol-1·cm-1,钍含量在 0～ 7μg·(2 5mL) -1范围内 ,符合比耳定律。经离子交换分离除去干扰离子 ,用本法测定了稀土精矿和寻乌矿中的微量钍。