1-(2,6-二氯-4-硝基苯)-3-(4-硝基苯)-三氮烯光度法测定葡萄糖酸锌中的锌

目前用光度法测定锌的有机试剂主要有双硫腙和偶氮类试剂。三氮烯试剂是一类测定 Cd2 +、Hg2 +等金属离子的灵敏试剂 ,但用于样品中的 Zn2 +的测定报道较少。笔者用新合成的显色剂 1 - ( 2 ,6-二氯 - 4-硝基苯 ) - 3- ( 4 -硝基苯 ) -三氮烯直接光度法测定葡萄糖酸锌口服液中的锌 ,样品不需前处理 ,操作简便 ,具有较高的灵敏度和较好的重现性     

5-溴-2-［（对-苯偶氮苯)-三氮烯］苯甲酸析相光度法测定痕量镉

1引言镉是具有蓄积性的有害元素,测定环境水样中痕量镉有一定的实际意义。三氮烯类试剂是测定镉、汞等过渡金属离子的优良显色剂,其选择性欠佳。显色剂5－溴－2－[（对-苯偶氮苯）-三氮烯]苯甲酸（BPBABTB）是新合成的三氮烯类试剂,已用于镉的一般光度法测定,而利用三氮类试剂进行析相光度分析尚未见报道。析相光度法具有同时富集和分离的作用,曾用于镍、铬、铜、锌及钻等的测定,但未见用于镉的测定。本文运用此显色剂进行了一般光度法和桥相光度法测定镉的比较研究,结果表明：在20％乳化剂OP,pH10,5的NaB4O7－NaOH缓冲介质…     

1-(2-羟基-5-硝基苯基)-重氮氨基偶氮苯与汞的显色反应

环境监测中通常采用双硫腙法和冷原子吸收光度法测定有毒元素汞。也有用三氮烯试剂测定微量汞的报道。三氮烯试剂与第ⅠB、ⅡB族金属元素有高灵敏度的显色反应,可用来测定样品中微量的Cd2+、Hg2+、Zn2+、Cu2+等金属离子[1-3]。本文用新合成的显色剂1 (2 羟基 5 硝基苯基) 重氮氨基偶氮苯测定工业废水样品中的汞,结果满意。1　实验部分移取一定量的汞标准溶液(不大于12μg)于25ml容量瓶中,依次加入3 5ml的Na2B4O7 NaOH缓冲溶液(pH=10 5),1 5ml2%的TritonX 100溶液和2 5ml0 04%的HNPDAAB无水乙醇溶液,以水定容,摇匀,于25°C发色…     

镉试剂与银显色反应体系中乙醇的超分子作用及其应用

金属离子、有机溶剂与偶氮类试剂之间存在一定的超分子作用,有机溶剂及缓冲介质的浓度对显色反应的灵敏度有很大的影响。据此建立了乙醇存在下的镉试剂与银的显色反应新体系。在pH9.5的硼砂-NaOH缓冲介质中,表面活性剂吐温-80的存在下,镉试剂与银反应生成2:1稳定配合物。络合物的λmax=518nm,摩尔吸光系数7.01×104L.mol-1.cm-1,银质量浓度0～1.0μg/mL范围内符合比尔定律。方法用于环境水样中银的测定,取得满意效果。     

过硫酸钾氧化偶氮荧光桃红催化光度法测定痕量银

以过硫酸盐氧化偶氮类试剂催化动力学法测定银,多数线性范围较窄、选择性欠佳。本文建立了以偶氮荧光桃红作指示物质、α,α′-联吡啶作活化剂的催化光度法,测定痕量银检出限为1.0×10^-4μg/mL,线性范围2.0×10^-4～4.0×10^-2μg/mL,灵敏度高,选择性好。用于测定鄂铜矿中银,结果满意。采用自装的微机动力学数据处理系统,测试简便、准确。     

以Triton X-100作增敏剂催化光度法测定痕量银

基于存在活化剂α,α′-联吡啶和增敏剂TritonX-100,银（Ⅰ）催化过硫酸钠氧化溴甲酚绿的反应,拟定了测定痕量银的新催化光度法,讨论了有关的反应机理。本法由于添加了TritonX-100,灵敏度提高了5倍,测定银含量线性范围为0．2～4．0μg/L,相对标准偏差为1．1％（n＝11）,检出限为6×10-11g／mL。可用于照相纸中银含量和AgCI溶度积的测定。     

安替比林基重氮氨基-2,4-二硝基苯与银(Ⅰ)的显色反应及其应用

本文报道了安替比林基重氮氨基－２，４－二硝基苯（ＡＰＤＮＢＴ）与银（Ⅰ）的显色反应．在吐温－８０存在下，ｐＨ＝９．０～１０．０的范围内，试剂与银（Ⅰ）形成２∶１的配合物；配合物对试剂的最大吸收在４８５ｎｍ处，ε为７．２×１０４Ｌ－１·ｍｏｌ·ｃｍ－１；提出了消除阳离子干燥的银镜分离法；方法用于测定合成试样及照相显影液中银的含量，回收率为９６～１０３％，相对标准偏差小于２．０％．     

(2,6-二溴-4-硝基苯)-3-(4-硝基苯)-三氮烯与银(Ⅰ) 的显色反应及其应用

研究了1-(2,6-二溴-4-硝基苯)-3-(4-硝基苯)-三氮烯(DBNPNPT)与Ag(Ⅰ)的显色反应。在Na2B4O7-NaOH缓冲溶液(pH=10.0)中和在Triton X-100存在下,试剂与Ag(Ⅰ)生成1∶1的配合物。该配合物在波长445 nm处有正吸收峰,在530 nm有负吸收峰,用双峰双波长法测得配合物的表观摩尔吸光系数为2.06×105L.mol-1.cm-1,符合比耳定律的范围为0~12μg/25mL。该法已用于回收定影液中银(Ⅰ)的测定,结果满意。     

2-(1,3,4-三氮唑偶氮)-5-二乙氨基苯甲酸光度法测定钒

有机偶氮类显色剂与钒 (Ｖ)形成络合物的分光光度法测定钒 ,灵敏度或选择性不高[1 ,2 ] ,我们曾合成了三氮唑偶氮类显色剂ＴＺＡＰＮ[3] 和ＣＴＺＡＰＮ[4] 以及四氮唑偶氮类显色剂ＴＺＡＤＡＰ[5] ,用于光度法测定钒 ,效果较好。为了进一步考察试剂结构对金属离子显色反应灵敏度和选择性的影响 ,以便筛选灵敏度和选择性更好的试剂 ,我们又设计合成了 2 ( 1 ,3,4 三氮唑偶氮 ) 5 二乙氨基苯甲酸 (简称ＴＺＤＢＡ)。探讨其与钒 (Ｖ)的显色反应条件 ,并用于铝合金样品及合成废水中钒的直接测定 ,结果令人满意。1　实验部分仪器 :ＵＶ - 2 4…     

银碘络阴离子-丁基罗丹明B-吐温-80体系双波长分光光度法测定岩矿中痕量银

方法基于CAgI_3]~(2-)络阴离子与丁基罗丹明B形成离子缔合物,用非离子表面活性剂吐温-80实现增溶增稳。提出了一个高灵敏度的双波长分光光度测定银的方法。缔合物最大吸收波长为605nm,负峰波长为555nm,摩尔吸光系数为3.26×10~5L·mol~(-1)·cm~(-1),0～8μgAg/25ml符合比耳定律。用于岩矿中痕量银的测定,结果满意。     

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。     

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.     

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.     

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。