阻抑褪色光度法测定微量硫代硫酸根

基于加热和pH =5 .0～ 6 .0条件下 ,硫代硫酸根抑制H2 O2 氧化结晶紫 (CV)的褪色反应 ,建立了测定硫代硫酸根的方法。硫代硫酸根在 4 .5× 1 0 -5～ 4 .5× 1 0 -4g/L范围内服从比耳定律 ,检出限为 3.2× 1 0 -6g/L。本法用于定影废液中硫代硫酸钠含量的测定 ,结果满意     

阻抑褪色光度法测定微量硫代硫酸根

基于加热和pH =5 .0～ 6.0条件下 ,硫代硫酸根抑制H2 O2 氧化结晶紫 (CV)的褪色反应 ,建立了一种测定硫代硫酸根的方法。硫代硫酸根在 4.5× 1 0 -5～ 4.5× 1 0 -4g/L范围内服从比耳定律 ;检出限为 3 .2×1 0 -6g/L。本法用于定影废液中硫代硫酸钠含量的测定 ,结果满意。     

催化动力学光度法测定痕量铜（Ⅱ）

研究了在磷酸介质中 ,铜 催化过氧化氢氧化偶氮胂Ⅰ褪色反应的适宜条件与影响因素 ,建立了动力学光度法测定痕量铜 的新方法。方法线性范围为 0～ 1 0 0 μg L ,检出限为 2 .79× 1 0 - 9g mL。该催化反应对Cu 为一级反应 ,表观活化能为 65 .6kJ mol,表观反应速率常数为 9.63× 1 0 - 4s- 1 。用于水样、电镀液和发样中铜 的测定 ,相对标准偏差为 0 .7%～ 4.7% ,标准加入回收率为 97.8%～ 1 0 4.2 %。     

阻抑动力学光度法测定对乙氧基苯胺的研究

在氨水介质中 ,痕量对乙氧基苯胺能灵敏地阻抑 Cu2 +催化过氧化氢氧化茜素红的褪色反应。本文研究了该反应的动力学参数 ,建立了一种测定对乙氧基苯胺的新方法。该法测定对乙氧基苯胺的线性范围为 0 .0～ 1 .0 μg/ 2 5m L,检出限为 8.54×1 0 - 7g/ L。用于环境水样中对乙氧基苯胺的测定 ,获得满意结果     

流动注射化学发光抑制法测定痕量钒(Ⅴ)

基于钒 (Ⅴ )对罗丹明B 过氧乙酸 NaOH体系化学发光具有强烈的抑制作用 ,建立了流动注射化学发光测定痕量钒 (Ⅴ )的新方法。该方法线性范围为2 .0× 1 0 - 9～ 1 .0× 1 0 - 6g/mL ,检出限为 3.0× 1 0 - 1 0 g/mL ,对 1 .0× 1 0 - 7g/mL钒(Ⅴ ) 7次平行测定的相对标准偏差为 2 .0 %。已用于环境水样、钢样中钒 (Ⅴ )的测定 ,初步探讨了发光反应及其抑制机理     

新体系催化动力学光度法测定痕量亚硝酸根

基于增敏剂吐温 - 80存在下亚硝酸根催化过氧化氢氧化中性红的反应 ,建立了测定痕量亚硝酸根的新催化动力学光度法。方法的灵敏度较常规方法提高了 2 .2倍 ,测定的线性范围为 2～ 1 0 μg/L,检出限为 2 .7× 1 0 - 10 g/m L。已用于测定水样中 NO2 - 的含量     

阻抑动力学光度法测定痕量间二硝基苯的研究

研究发现 ,在硫酸介质中 ,痕量间二硝基苯能灵敏地阻抑 Fe3+催化高碘酸钾氧化甲基兰褪色。研究了该阻抑褪色反应的最佳条件及动力学参数 ,建立了一种测定痕量间二硝基苯的新方法。该法测定线性范围为 0 .0～ 8.0μg/L,检出限为 1 .6× 1 0 - 6 g/L。用于环境水样中间二硝基苯的测定 ,结果满意     

阻抑-褪色光度法测定痕量硅

基于NH3 NH4 Cl缓冲溶液介质中 ,Si 对H2 O2 氧化十六烷基三甲基溴化铵 姜黄素离子缔合物的褪色反应的抑制作用 ,提出了测定痕量硅新的高灵敏的褪色光度法。该方法的表观摩尔吸光系数ε50 0=5 .70× 10 5L·mol-1·cm-1;线性范围为 0 .4～ 3.6 μg/L ;线性回归方程ΔA =2 .2 3× 10 -4 + 0 .0 2 0 17CSi (μg/L) ;相关系数r =0 .9999;测定下限为 2 0× 10 -8g/L。本法用于人发样和水样中痕量硅的测定 ,结果满意。     

萃淋树脂分离-全差示光度法测定环境水样中铬Ⅲ和铬Ⅵ

用CL TBP萃淋树脂分离富集Cr 和Cr 、对氨基二甲基苯胺做显色剂 ,采用全差示光度法测定环境水样中的Cr 和Cr 。方法的表观摩尔吸收系数为 3.42× 10 5L·mol- 1 ·cm- 1 ,线性范围为 0～ 0 .16mg/L ,线性方程为A =6 .7C +0 .0 0 1,(C :mg L) ,r =0 .9996 ,Cr 和Cr 的检测限分别为 8和 6 μg L。测定Cr 和Cr 分别为 18.7和 31.6 μg L ,其相对标准偏差分别为 3.1%(n =6 )和 2 .4%(n =6 )。Cr 和Cr 的标准加入回收率为 93.3%～ 10 2 .3%。用本法测定环境水样中Cr 和Cr ,结果满意。     

偶合化学发光法测定环境水样中的痕量亚硝酸根

将亚硝酸盐在酸性条件下氧化亚铁氰化钾为铁氰化钾的反应 ,和尿酸 铁氰化钾 鲁米诺化学发光反应偶合一起 ,建立了一种间接测定亚硝酸根离子的新方法。讨论了酸度、反应物浓度、干扰离子等因素的影响。方法的检出限为5 .0× 1 0 - 1 1 g/mL ,对环境水样样品进行了平行测定 (n =1 1 ) ,其相对标准偏差为1 .8%～ 3 2 % ,线性范围为 1 .0× 1 0 - 9g/mL～ 1 .0× 1 0 - 5g/mL ,回收率为 94.3%～ 1 0 5 3%。     

利用手持技术改进测定乙醇分子结构实验

利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。     

光谱仪测试范围的扩展

由于石化行业的生产需要，其材质的使用具有多样性和广泛性，经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识，根据光谱仪的测试能力及标样的采集，实现了一个或几个元素测量范围的扩展，并对其测量的影响因素进行了研究。     

Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin

The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

物质分配系数的测定实验改进

实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。     

Calculation of enthalpies of hydrogenation of hydrocarbons

Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。