三烷基氧化膦中脂肪酸的气相色谱测定

报道了用气相色谱测定萃取剂三烷基氧化膦中的微量脂肪酸。用碳酸钠溶液萃洗分离三烷基氧化膦,在甲醇溶液中用四甲基氢氧化铵作为甲基化试剂,反应在裂解进样器中进行,回收率为90％－105％,误差在10％以内。     

用锰（IUI）—氨三乙酸—溴代十六烷基三甲胺—高碘酸钾—烂灿甲酚蓝…

基于存在活化剂氨三乙酸和增敏剂溴代十六烷基三甲胺，锰（Ⅱ）催化高碘酸钾氧化灿烂甲酚蓝的反应，拟定了测定痕量锰的催化光度法，讨论了有关反应机理。本法由于添加了溴代十六烷基三甲胺，灵敏度提高２．５倍，测定锰含量线性范围为８．０×１０＾－４￣８．０×１０＾－３ｍｇ／Ｌ，检出限为７．０×１０＾－５ｍｇ／Ｌ，相对标准偏差为４．７％（ｎ＝１１），可用于测定茶叶和水样中的锰。     

硝基磺酚S作为酶联免疫分析中辣根过氧化物酶测定底物的研究

提出一种新的ＨＲＰ底物－硝基磺酚Ｓ,初步探讨了在ＨＲＰ催化下被过氧化氢氧化的机制,以硝基磺酚Ｓ为底物测定了酶促反应动力学常数Ｋｍ和Ｋｓ分别为４．５１×１０＾－５ｍｏｌ／Ｌ和２８．１ｍｏｌ／Ｌ·ｓ＾－１。分别用于酶联免疫显色光度法和伏安酶联免疫分析法测定了ＩｇＧ－ＨＲＰ,其所能测定的最高稀释比分别为１：１．６×１０＾５和１：４．８×１０＾５。     

烷基磷(膦)酸酯~(31)P NMR的取代基效应

本文利用分子力学计算,将核磁共振中烷基取代基效应的Van der Waal模型扩展到磷酸三烷基酯、烷基膦破二烷基酯、二烷基膦酸烷基酯和三烷基氧化膦。在各类磷化合物中,δ~(31)P和E_(vdw·p)之间存在有良好线性关系。此外,还用分子力学计算方法和变温核磁共振谱方法探讨了一系列烷基膦酸O,O-1,3-亚丙酯和烷基膦酸O,O-1,4-亚丁酯的构型平衡。在气相和非极性溶剂中,前者以烷基处于平键的椅式构型存在,后者以烷基处于平键的扭船式构型存在。     

荧光光度法同时测定稀土氧化物中铈钆铽

在０．６ｍｏｌ．Ｌ＾－１的 到介质中,分别用２５２、２７３、２２０ｎｍ作为Ｃｅ＾３＋、Ｇｄ＾３＋、Ｔｂ＾３＋的激发波和燕生相应最佳发波长为３５０、３１０和５４４ｎｍ。用盐酸体系测定混合样比用硫酸体系测定时,Ｇｄ＾３＋的检出限提高一倍,Ｇｄ＾３＋抗Ｃｅ＾３＋的干扰能力提高１０倍。同时测定三种离子的回收率在９５．３％～１０８．１％之间。     

罗丹明 6G 褪色光度法测定氯酸根

提出了罗丹明６Ｇ褪色光度法测定微量氯酸根离子的新方法,研究了氯酸根在盐酸介质中氧化罗丹明６Ｇ使其褪色的最佳条件。最大吸收波长λｍａｘ在５２５ｎｍ处,其表观摩尔吸光系数ε为１．２２×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,氯酸根的质量浓度在０￣６μｇ／２５ｍＬ范围内符合比耳定律。已用于化学试剂中氯酸根的测定,结果满意。     

胶束增敏紫外吸光光度法测定甲睾酮

用紫外吸光光度法对硫酸介质中甲睾酮与溴化十六烷基三甲铵形成的胶束配合物的性能和条件进行了系统研究，提出了利用胶束的增增敏稳作用测定甲睾酮的紫外吸收光光度新方法，本法的灵敏度高，表观摩尔吸光系数ε２４４为２．２８×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，检出限为２．４×１０＾－７ｍｏｌ．Ｌ＾－１，用于片剂中甲睾酮含量的测定，与药典对照结果吻合。     

相转移催化合成苯基烷氧羰基甲基次膦酸酯和二苯基烷氧羰基甲基氧化叔膦

液-液相转移催化 P-烷基化反应的研究工作还不多。Kem 等曾用亚磷酸二烷基酯或二烷基氧化膦与氯代的取代乙酰胺通过液-液相转移法合成了取代胺基羰基与甲基膦酸酯及氧化叔膦。我们曾研究了亚膦酸二烷基酯与氯     

有机磷化合物的研究 ⅠⅣ.合成烷基膦酸单酯衍生物的新方法

Atherton与Todd等1945年就用亚磷酸二烷基酯在四氯化碳中与有机胺反应得到二烷基磷酰胺.我们曾成功地由二烷基亚磷(膦)酸在四氯化碳存在下与多种亲核试剂反应合成二烷基磷(膦)酸酯及其衍生物.实验表明二烷基亚膦酸的反应性和亚磷酸二烷基酯有很大差别,为进一步考察不同的三配位磷化合物在该反应中的反应性能,我们合成了己基亚膦酸单烷基酯并在四氯化碳中与各种亲核试剂进行氧化膦酰化反应,制得了相应的己基膦酸单酯衍生物,得率良好,为合成烷基膦酸单酯衍生物的新方法.     

大孔磷酸树脂吸收镧的研究

本文测定了大孔膦酸树脂对Ｌａ＾３＋的吸附容量，介质ｐＨ、温度、吸附时间等因素对吸附的影响，测得吸附速率常数Ｋ２９８＝７．６４×１０＾－５Ｓ＾－１，树脂功能基与Ｌａ＾３＋的络合比为３：１，用化学及红外光谱等方法，得到大孔膦酸树脂吸附Ｌａ＾３＋的基本参数及其机理。     

Lewis碱性混合萃取剂碱度的测定

提出一种利用萃取法间接测定Lewis碱性萃取剂碱度的简便方法, 选择常用的Lewis碱性萃取剂TOA/正辛醇和TRPO/煤油, 测定了其碱度, 为今后络合萃取剂的选择及其机理的研究提供理论指导.     

Synergistic extraction of rare earths with bis(2,4,4-trimethyl pentyl) dithiophosphinic acid and trialkyl phosphine oxide

Synergistic extraction of trivalent rare earths from nitrate solutions using mixtures of bis(2,4,4-trimethylpentyl)dithiophosphinic acid (Cyanex 301=HX) and trialkyl phosphine oxide (Cyanex 923=TRPO) in xylene has been investigated. The results demonstrate that these trivalent metal ions are extracted into xylene as MX(3).3HX with Cyanex 301 alone. In the presence of Cyanex 923, La(III) and Nd(III) are found to be extracted as MX(2).NO(3).TRPO. On the other hand, Eu(III), Y(III) and heavier rare earths are found to be extracted as MX(3).HX.2TRPO. The addition of a trialkylphosphine oxide to the metal extraction system not only enhances the extraction efficiency of these metal ions but also improves the selectivities significantly, especially between yttrium and heavier lanthanides. The separation factors between these metal ions were calculated and compared with that of commercially important extraction systems like di-2-ethylhexyl phosphoric acid.     

Determination of light hydrocarbons dissolved in seawater

A practical method for the on board determination of light (C1-C4) hydrocarbons dissolved in seawater has been developed. The gaseous hydrocarbons in seawater were extracted quickly with a vacuum sparge tower and determined gas chromatographically. By using two cryogenic columns at dry ice-ethanol temperature (-80 degrees C) connected in series, it was possible to completely collect the hydrocarbons. The precision and sensitivity were comparable to that of previous methods. The analysis was completed within 45 min for one sample and the sample volume was 500 ml. The method was successfully applied to the northern North Pacific water collected in summer 1997. The concentrations of C2-C4 hydrocarbons in surface seawater ranged from several to several tens pmol l(-1), within the range of concentrations in previous studies.     

Ab initio analysis of monomers and dimers of trialkylphosphine oxides: Structural and thermodynamic stability

Structural and thermodynamic stabilities of monomers and dimers of trialkylphosphine oxides (TRPO) were studied using quantum chemistry calculations. Density functional theory calculations were carried out and the structures of four TRPO have been determined: TMPO (methyl; R = CH₃), TEPO (ethyl; R = CH₃CH₂), TBPO (n‐butyl; R = CH₃(CH₂)₃), and TOPO (n‐octyl; R = CH₃(CH₂)₇). TRPO homodimers were investigated considering two isomeric possibilities for each dimer. Relative binding energies and the enthalpic and entropic contributions to the Gibbs free energy were calculated for all dimers. The formation of dimers from the individual monomeric TRPO species as a function of temperature was also analyzed. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009     

碱金属萃取化学的研究 III:弱酸性偶氮螯合剂化学结构对萃取锂的性能研究

The synergistic extractic extraction of lithium with a solution of o-phenylazophenols (HAX) and trioctylphosphine oxide (TOPO) or other trialkylphosphine oxide (TRPO, R = C8-10) in o-dichlorobenzene from aqueous solution of lithium hydroxide was reported. The structural effect of o-phenylazophenols on extraction of lithium has been examined. In the case of 1-(p-X-phenylazo)-2-naphthols, the HMO calculation shows that the charge density of azo nitrogen atom(the donor atom, denote azo N) and hydroxyl oxygen atom does not very apparently, so that the stability of their chelates with lithium has no obvious variations as well. In this case their ability to extract lithium is chiefly governed by the pKa. of the compound. The results of extraction prove that there is a linear correlation between the extraction constant Kex and pKa. However, for the second group of chelating agents, the change of their structure leads to the change of the change of both pKa and stability of chelates. The results of extraction and HMO calculation show that the stability of chelates is mainly influenced by the strength of the coordination bond, i.e. the larger the charge density of azo N (qN), the more stable the chelate will be. Therefore, their ability to extract lithium is roughly directly proportional to the stability of chelates and inversely to the pKa. the strength of coordination bond for the chelates can be experimentally measured by means of the strength of intramolecular hydrogen bond of chelating agent, ΔδOH (the diference of chemical shift of hydroxyl proton in free and bonded state). Therefore, the ratio, ΔδOH/pKa, can be used to evaluate the extraction ability of chelating agents to lithium. We find that it is approximately proportional to the distribution ratio (D).     

Study on liquid scintillation technique for bioassay of plutonium

Simple, rapid and sensitive methods are very important for the bioassay of plutonium. In this work, modern liquid scintillation technique combined with selective extraction separation and / pulse decay discrimination were studied and evaluated for the bioassay of plutonium. After sample decomposition and partial evaporation, cyclohexanone and trialkylphosphine oxide (TRPO) were used for the separation of plutonium from matrix. Several different cocktails were tested for liquid scintillation analysis of urine samples. The minimum detectable activity (MDA) of this method was estimated to be 0.01 Bq/500ml urine with 100 minutes measuring time and 3 confident level.     

Properties of TRPO-HNO_3 complex used for direct dissolution of lanthanide and actinide oxides in supercritical fluid CO_2

The mixed trialkylphosphine oxide-nitric acid (TRPO-HNO3) complex prepared by contacting pure TRPO with concentrated HNO3 may be used as additives for direct dissolution of lanthanide and actinide ox- ides in the supercritical fluid carbon dioxide (SCF-CO2). Properties of the TRPO-HNO3 complex have been studied. Experimental results show when the initial HNO3/TRPO volume ratio is varied from 1:7 to 5:1, the concentration of HNO3 in the TRPO-HNO3 complex changes from 2.12 to 6.16 mol/L, the [HNO3]/[TRPO] ratio of the TRPO-HNO3 complex changes from 0.93 to 3.38, and the content of H2O in the TRPO-HNO3 complex changes from 0.97% to 2.70%. All of the density, viscosity and surface tension of the TRPO-HNO3 complex change with the concentration of HNO3 in the complex. The protons of HNO3 and H2O in the complex undergo rapid exchange to exhibit a singlet resonance peak in NMR spectra with D2O insert. When the TRPO-HNO3 complex dissolves in a low dielectric constant solvent, small droplets of HNO3 appear which can be detected by NMR.     

Radiochemical study of hydrolysable carbides

A simple radiochemical method has been developed for the phase analysis of hydrolysable carbides. The method is based on the radio gas chromatography of gaseous products of carbide hydrolysis with simultaneous mass and activity detection. The tritium-labelled hydrocarbons evolved (tritium oxide used for hydrolysis) are characteristic of the individual carbide phases. An application for Group III b carbide phase analysis is demonstrated.     

Measurement of diffusion coefficients in multicomponent gas mixtures by the reversed-flow technique

Summary The reversed-flow method for measurement of gas diffusion coefficients in binary mixtures is now extended to simultaneous determination of effective diffusion coefficients for each substance in a multicomponent gas mixture. The method is applied to six ternary mixtures, each consisting of two gaseous hydrocarbons and H₂, He or N₂. The results are in agreement with a limiting case of the Stefan-Maxwell equations.     

Determination of nitrated-polyaromatic hydrocarbons (nitro-PAHs) in environmental samples by high resolution chromatographic techniques

An analytical procedure is described for the fractionation of organic compounds present in environmental samples and the determination of nitro polyaromatic hydrocarbons (nitro-PAHs). Both low and high resolution liquid chromatography are employed for the prefractionation of the soluble organic fraction (SOF) extracted from particulate matter or gaseous pollutants collected on adsorption traps. High resolution gas chromatography is used to analyze four fractions containing alkanes, PAHs, nitro-PAHs, and other polar PAHs. Nitrogen-containing species are separated by GC and detected specifically using an alkali flame (NPD) detector. Flame ionization (FID) detection, GC-MS of positive ions, and negative ion chemical ionization MS of the whole fraction is used for the identification and quantitation of the various components. The composition of SOF extracted from particulate matter emitted from diesel exhausts is elucidated and a large number of nitro-PAHs identified by the combination of the various techniques.