三维荧光光谱法连续测定苯胺、二苯胺和N-甲基苯胺

本文比较了苯胺、二苯胺、N-甲基苯胺的二维荧光光谱和三维荧光光谱。提出了同时测定苯胺,二苯胺和N甲基苯胺的分析方法,它们的浓度分别在2.0×10~(-7)～5.0×10~(-6)mol/L,9.0×10~(-8)～7.4×10~(-6)mol/L,1.3×10~(-7)～2.0×10~(-8)mol/L范围内有良好的线性关系,检出限为1.0×10~(-7)mol/L,8.0×10~(-9)mol/L,1.0×10~(-7)mol/L.相对标准偏差分别为5％,7％,7％.此方法用于混合样品和工业废水的分析,获得较满意的结果.     

浙江不同地区银杏叶中微量元素的研究

用荧光分光光度法和能量色散X荧光分析法测定了浙江不同地区银杏叶中某些微量元素含量的变化。结果表明:不同地区的银杏叶中微量元素硒、铜、锌、铬、铁和锰的含量范围分别为0.1～2.17×10~(-6),2.8～6.9×10~(-6),6.1～17.1×10~(-6),1.1～6.6×10~(-6),74～399×10~(-6)和15～73×10~(-5).     

铬(Ⅵ)-亚铁氰化钾-鲁米诺体系化学发光反应的研究

本文通过对铬(Ⅵ)-亚铁氰化钾-鲁米诺体系化学发光反应的研究,建立了一个测定铬(Ⅵ)的高灵敏化学发光分析法。方法的检出限为2×10~(-11)g/ml铬(Ⅵ);相对标准偏差小于2％(对1×10~(-10)g/ml铬(Ⅵ)11次测定);校正曲线的线性范围是1×10~(-10)～6×10~6g/ml铬(Ⅵ)。此方法已用于环境水样中铬(Ⅵ)的测定。     

无机偶合反应化学发光分析 Ⅱ.H_2O_2-Na_2S_2O_3-鲁米诺体系测定痕量钼

本文将钼催化过氧化氢氧化硫代硫酸钠的反应与鲁米诺-H_2O_2化学发光反应相偶合,建立了痕量钼的无机偶合反应化学发光分析法。此方法的检出限是1.2×10~(-10)g/ml钼,相对标准偏差为2.7％(对5×10~(-9)g/ml钼11次测定),工作曲线的线性范围为1×10~(-9)～1×10~(-3)g/ml。此法巴成功地用于天然水中痕量钼的测定。     

丁基罗丹明B-高碘酸钾动力学光度法测定铑

报道了以铐催化高碘酸钾氧化丁基罗丹明B为基础的动力学测定痕量铑的方法,详细研究了动力学条件,建立了动力学光度测定痕量铑的新方法,铑浓度在0～180μg/L范围内与log(A_o/A)呈线性关系,检出限为2.84×10~(-7)g/L,该反应对Rh(Ⅲ)或丁基罗丹明B为一级反应,表观活化能为64.04kJ/mol.本方法用于某些催化剂中铑的测定,其相对标准偏差为1.76%～3.46%,回收率为96.8%～104.7%.     

超痕量钌的催化光度分析—KIO4—罗丹明B新体系

钌的催化动力学分析法颇多,但检出限低于10~(-9)g/L级的甚少。Alekseeva等基于Ru(Ⅲ)对IO_4~-氧化[Fe(phen)_3]~(2+)反应的催化作用,建立了一个检出限和测定范围分别为5×10~(-9)g/L和10—140×10~(-9)g/L Ru的催化电位法。Rysev等利用Ru(Ⅲ)-IO_4~--金莲橙OO催化褪色体系可测定2×10~(-9)g/L的Ru。     

以盐酸肼还原天青I催化光度法测定痕量钼

基于天青Ⅰ与盐酸肼氧化还原反应钼的催化活性,拟定了测定痕量钼新的动力学方法。本法钼的检测限为6×10~(-4)μg/ml,可测定浓度范围为1×10~(-3)～9×10~(-1)μg Mo/ml。本法可用于井水、温泉水和废水中钼的测定。     

溴酸钾—偶氮氯膦Ⅲ—硫酸体系催化光度法测定钯

研究了在0.45mol·L~(-1)H_2SO_4介质中,痕量钯催化溴酸钾氧化偶氮氯膦Ⅲ这一新指示反应的动力学条件。建立了催化光度法测定钯的新方法。测定范围为0～0.4μg/25ml,摩尔吸光系数为4.8×10~6。用于合成样品及含钯催化剂的分析,结果满意。     

痕量银的催化动力学—离子选择电极法测定

1 引言 催化动力学分光光度法测定痕量银已有很多报道,但应用催化动力学-离子选择电极法测定尚属少见。本文利用下列指示反应:选用0.02mol/LCe(Ⅳ)-4×10~(-5)mol/L KCl-0.02mol/L H_2SO_4体系,采用氯离子选择电极作监测器,进行了痕量银的催化动力学-离子选择电极法测定。试验证明,本方法仪器简单,操作方便,线性范围为0～0.8μg/50ml,检出限量为5×10~(-4)μg/ml,用于矿物标样分析,取得令人满意结果。     

催化光度法测定痕量铜的研究 Cu(Ⅱ)-次甲基蓝-H_2O_2体系

在氨水介质中,痕量Cu(Ⅱ)对H_2O_2氧化次甲基蓝的反应有强烈的催化作用。由此建立的痕量CU(Ⅱ)的催化光度分析法的检测限为1.5×10~(-10)g/ml。测定范围为0～0.7μg/25ml。测得催化及非催化反应的表观活化能分别为9.15kJ/mol及14.13kJ/mol。样品分析结果良好。     

Syntheses, Structures and Thermal Stabilities of Three Novel Lanthanide Coordination Polymers with 6-Hydroxynicotinic Acid

Three novel lanthanide coordination polymers {[Ce₂(HOnic)₄(Onic)₂(H₂O)₂]·6H₂O}_n ( 1 ), {[Ln(HOnic)(Onic)‐ (H₂O)₅·(HOnicH)]·H₂O}_n [HOnicH=6‐hydroxynicotinic acid, Ln=Nd ( 2 ), Pr ( 3 )] have been synthesized and characterized by elemental analyses, IR spectrum and single crystal X‐ray diffraction. Structure analyses reveal that 1 features a 2D plane structure while compounds 2 and 3 possess a 1D chain‐like polymeric structure. TG analyses indicate that 1 exhibits higher thermostability than 2 and 3 , which was attributed to the layer polymeric structure of 1 .     

过氧化氢-巯嘌呤氧化还原反应的研究及荧光分析应用

研究了过氧化氢氧化巯嘌呤的反应条件及产物的荧光特性 ,提出了高灵敏荧光光度法测定巯嘌呤含量的新方法。在碱性介质和沸水浴加热条件下 ,过氧化氢能将巯嘌呤定量转化为 6-嘌呤磺酸钠 ,其体系的荧光强度与巯嘌呤浓度在6.0× 1 0 -8～ 1 .0× 1 0 -5mol/L范围内呈线性关系 ,检出限为 2 .4× 1 0 -8mol/L。该法已用于片剂中的巯嘌呤含量的测定。     

荧光光谱法研究6—巯基嘌呤的氧化反应及其分析应用

系统地研究了高锰酸钾对６－巯基嘌呤的氧化作用,提出了高灵敏测定６－巯基嘌呤的荧光光度分析新方法。在碱性介质中,氧化产物的荧光强度较６－巯基嘌呤处身的荧光强度提高了１０倍,且稳定性好。本体系的激发波长为２８６ｎｍ,发射波长为３９７ｎｍ,荧光强度与６－巯基嘌呤的浓度在０．００６４～３．０μｇ／ｍＬ范围内呈线性关系,检测限为０．００３２μｇ／ｍＬ。应用该法于片剂中６－巯基嘌呤含量的测定,与标准方法对照,     

Dynamic mechanical analysis of RIM nylon-6

The β relaxation process was shown to occur at different temperatures and exhibit a different activation energy for dry and wet samples prepared by reaction injection molding (RIM) of Nylon-6. By employing a low operating frequency and controlled low moisture levels, it became possible to distinguish the two β relaxation processes, β₁ and β₂, in one sample by dynamic mechanical spectroscopy. It was shown that while β₁ was associated with moisture in the sample, β₂ was related to a structural mechanism independent of moisture. The effect of moisture content on the chain-chain association (α relaxation process) and chain-water association (β₁, relaxation process) in nylon-6 was assessed. The annealing mechanism of RIM Nylon-6 at 85°C was probed by both dynamic mechanical spectroscopy and x-ray diffraction.     

Kinetics and Mechanism of the Pudovik Reaction

Abstract

The kinetics and the mechanism of the Pudovik reaction for the series of α, β-unsaturated carbonyl compounds have been studied. The factors which determine the addition locoselectivity and the reactivity of the hydrophosphoryl and unsaturated compounds in this process are established. The qualitative and quantitative relationships obtained allow to predict the reaction rate and its direction depending on the reagents structure and also on the nature of catalyst and solvent used.     

Synthesis and Crystal Structure of a Novel Zinc Complex [Zn(OH_2)(HDPA)_2]·3H_2O

1INTRODUCTION In recent years,dicarboxylic acids have been wide-ly used as poly-dentate ligands involved in various metal chelation reactions to form transition or rare earth metal complexes with interesting properties in material science[1~3]and biological systems[4~7].For example,Kim,Y.and his coworkers focus on the syn-theses of copper(II)complexes containing ligands of malonate and pyrazine to study their electronic con-ductivity and magnetic property[8].The importance of Tr(II)/dic…     

Crystallographic evidence of hexacoordination at phosphorus via intramolecular coordination of donor groups on phosphane and phosphane sulphide

The X-ray structure analysis of bis(8-dimethylamino-l-naphthyl)phenylphosphane (3) and of the corresponding sulphide 4 has revealed hexacoordination at phosphorus in both cases, the N … P separations being less than the sum of the van der Waal radii. Furthermore, in both cases the overall geometry corresponds to a distorted bicapped tetrahedron. The optimum geometry calculated for 4 via the program developed by Autodesk (MM + method) suggests that the structure of the molecule is a function not only of steric requirements but also of electronic effects.     

流动注射化学发光增强法测定巯嘌呤的应用研究

试验发现6-巯基嘌呤对Luminol-H2O2-OH-体系的化学发光有较强的增敏作用。据此建立了一种流动注射化学发光增强法测定6-巯基嘌呤的新方法。该法测定6-巯基嘌呤的检出限为7.5×10-9mol/L,线性范围为2.0×10-8~2.5×10-6mol/L,对6.0×10-7mol/L的6-巯基嘌呤测定的相对标准偏差为1.6%(n=11),已用于合成样中6-巯基嘌呤的测定。     

Structural investigation of 1-(N,N-dimethylaminomethyl)-spirobi(3-oxo-2,5-dioxa-1-silacyclo-pentan)ates

1-[(N,N-Dimethyl)aminomethyl]spirobi(3-oxo-2,5-dioxa-1-silacyclopentan)ate and 1-(N,N-dimethyl)-aminomethyl]spirobi(4,4-dimethyl-3-oxo-2,5-dioxa-1-silacyclopentan)ate are representatives of amino-methylspirobi(3-oxo-2,5-dioxa-1-silacyclopentan)ates, which are electrostatically stabilized silanates (ES silanates). X-ray diffraction structural analysis and quantum-chemical calculations were used in a structural study of these compounds. The factors affecting the geometry of these molecules are discussed. Dedicated to Academician Janis Stradins on the Occasion of His 75^th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1873–1881, December, 2008. An erratum to this article can be found at     

毛细管电泳前沿分析法研究钾离子与18-冠醚-6体系相互作用

采用毛细管电泳前沿分析(CE／FA)法，利用间接紫外检测方法，在pH为5．10，运行电压为30kV，缓冲溶液组成为咪唑和醋酸的条件下，测定了钾离子与18-冠醚-6体系的相互作用参数，结合常数对数值lgK=3．50；在同样条件下用峰漂移法作对照实验，求得体系的结合常数对数值lgK=3．40，结果与前沿分析法基本一致。验证了两种方法测定结果的正确性。