液相色谱分离-氢化物原子吸收测定血清中不同形态的有机砷化合物

建立了一种色谱分离－紫外线消解－氢化物原子吸收光谱测定６种有机砷化合物的方法。这６种砷化合物分别是：甲基胂酸（ＭＭＡ）,二甲基胂酸（ＤＭＡ）,胂三甲胺内酯,胂胆碱,三甲基氧化胂和四甲基胂。由于ＡｓＢ,ＡｓＣ和ＴＭＡｓ＾＋不能直接与ＮａＢＨ４反应产生氢化物,因此在色谱柱与检测器之间增设了一个紫外线消解装置,使这些砷化合物在发生氢化物前先行消解。     

THE RETENTION BEHAVIOR OF ARSENIC COMPOUNDS ON PRP-X100 COLUMN UNDER ALKALINE CONDITION

系统地研究了碱性条件下（ｐＨ８～１０．８）Ａｓ３＋，Ａｓ５＋，ＭＡ，ＤＭＡ和ＡＢ等砷化合物在ＰＲＰ－Ｘ１００阴离子交换柱上的保留行为。用火焰原子吸收光谱（ＦＡＡＳ）测定从ＨＰＬＣ分离的砷化合物，即通过一根１ｍ×０．２３ｍｍｉ．ｄ．不锈钢毛细管，将ＨＰＬＣ柱出口与ＦＡＡＳ的雾化器连接起来，采用乙炔／空气火焰，在１９３．７ｎｍ处测定。具体研究了两个流动相（２０ｍｍｏｌ／ＬＮＨ４ＨＣＯ３和２．５ｍｍｏｌ／Ｌ对－羟基苯甲酸－１．０ｍｍｏｌ／Ｌ苯甲酸水溶液），并系统研究了ｐＨ值和缓冲液浓度对上述５个砷化合物的保留时间的影响，发现对于２０ｍｍｏｌ／ＬＮＨ４ＨＣＯ３体系，在ｐＨ８．７时，ＡＢ，Ａｓ３＋，ＤＭＡ可以得到完全分离，通过梯度洗提（ｐＨ８．７到９．８，流速１．６５ｍＬ／ｍｉｎ），在１５ｍｉｎ内上述５个砷化合物可以得到良好分离；对于２．５ｍｍｏｌ／Ｌ对－羟基苯甲酸－１．０ｍｍｏｌ／Ｌ苯甲酸体系，在ｐＨ９．０及流速１．５ｍＬ／ｍｉｎ时，可以在１２ｍｉｎ内将上述５个砷化合物分离。     

The retention behavior of arsenic compounds on PRP-X100 column under alkaline condition.

系统地研究了碱性条件下（ｐＨ８～１０．８）Ａｓ３＋,Ａｓ５＋,ＭＡ,ＤＭＡ和ＡＢ等砷化合物在ＰＲＰ－Ｘ１００阴离子交换柱上的保留行为。用火焰原子吸收光谱（ＦＡＡＳ）测定从ＨＰＬＣ分离的砷化合物,即通过一根１ｍ×０．２３ｍｍｉ．ｄ．不锈钢毛细管,将ＨＰＬＣ柱出口与ＦＡＡＳ的雾化器连接起来,采用乙炔／空气火焰,在１９３．７ｎｍ处测定。具体研究了两个流动相（２０ｍｍｏｌ／ＬＮＨ４ＨＣＯ３和２．５ｍｍｏｌ／Ｌ对－羟基苯甲酸－１．０ｍｍｏｌ／Ｌ苯甲酸水溶液）。     

氢化物发生—冷阱捕获—色谱分离—原子吸收法测定天然水中坤的形态

研究建立了氢化物发生－冷阱捕获－色谱分离－原子吸收方法测定天然水中四种主要砷形态，测试系统自行组装，色谱柱填料采用ＣｈｒｏｍｏｓｏｒｂＧＡＷ－ＤＭＣＳ（粒径０．３～０．４５ｍｍ），其上涂布３％ＯＶ－１０１。方法的检出限以砷计分别为：Ａｓ（Ｖ）０．５１ｎｇ，Ａｓ（Ⅲ）０．４３ｎｇ，ＭＭＡ０．３８ｎｇ，ＤＭＡ０．６７ｎｇ；１２ｎｇ砷标准偏差为Ａｓ（Ⅴ）４．２１％，Ａｓ（Ⅱ）３．５６％，ＭＭＡ３．２３％     

植物中砷的形态分析

应用离子交换树脂静态吸附和溶剂萃取相结合的分离技术，分析了植物中砷的四种形态化合物：无机三价砷和五价砷，一甲基胂和二甲基胂。并用石墨炉原子吸收光谱法（ＧＦＡＡＳ）测定其含量。文中采用ＨＣｌ浸提植物的砷，并对ＨＣｌ的浓度、体积以及浸提时间作了详细的探讨。用２０ｍＬ１ｍｏｌ／ＬＨＣｌ对１．０ｇ干植物２ｄ的浸出量与传统消化法总量的比值为０．８５－１．００。对浸出液进行形态分析，总砷回收率为８６％－９３％     

聚铝共沉淀氢化物发生（HG）—ICP—AES法测定痕量砷

采用孔雀绿与砷钼酸盐形成离子对,以聚铝作为共沉淀剂富集分离,ＨＧ－ＩＣＰ－ＡＥＳ法测定痕量砷的新方法。对离子对化合物的形成,聚铝共沉淀及氢化物发生条件进行了试验及优化。实验结果表明,显著改善了测定Ａｓ的灵敏度和选择性。当富集倍数为２０时,方法的检出限达０．０９μｇ／Ｌ。     

荧光熄灭法测定痕量砷（Ⅲ）

１　引　言砷（Ⅲ）对生物体的影响较大，在人体代谢过程中易于某些部位累积，引起慢性中毒，已列为公害病之一，因此，痕量砷（Ⅲ）的测定意义重大。砷（Ⅲ）的测定多采用ＡＡＳ法及ＩＣＰ法。近年来建立了一些荧光分析方法。由于实际样品中的砷（Ⅲ）含量极低，测定时常要富集，给测定带来不便。本文首次报道了新试剂７－［（２，４－羟基－５－羧基苯）偶氮］－８－羟基奎啉－５－磺酸（简称ＤＨＣＢＡＱＳ）与Ａｓ（Ⅲ）反应的荧光性能，建立起测定痕量砷（Ⅲ）的新方法，该方法灵敏度高，选择性好，操作简便快速，无须富集，可直接测定…     

示波极谱法快速测定金属铜中微量砷

提出了一个快速测定金属铜中微量砷的新方法。采用铁氰化钾－亚铁氰化钾沉淀分离基体铜等与微量砷相分离,并用催化示波极谱测定,效果良好。     

荧光法测定环境水中的痕量砷

建立了测定环境水中痕量砷的荧光新方法,在ＰＨ６．５－７．５的缓冲介质中,利用２′,７′－二氯荧光素（ＤＣＦ）作为荧光试剂,激发波长λｅｘ＝５１０ｎｍ,发射波长λｅｍ＝５２８ｎｍ下,测定痕量砷,亚砷酸根浓度在０．２５－３．５０μｇ／２５ｍＬ范围内,相对荧光强度差值与亚砷酸根浓度呈线性关系,检测限为０．１６μｇ／２５ｍＬ,用于检测自来水和池塘水中的痕量砷,回收率为９５％－１０５％。     

ICP-AES法测定粗氧锑中砷硒

３用浓硫酸溶解粗氧锑,ＩＣＰ－ＡＥＳ法直接测定砷。对于样品中的痕量硒,先以次磷酸钠还原单质,并与砷共沉淀,经浮选分离后再测定。对硒的分离条件进行了优化。考察了基体锑的干扰及共存杂质的影响。方法运用于粗氧锑样品中砷、硒测定、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。     

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。     

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.     

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.     

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.     

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。