硫代米蚩酮—乳化剂OP分光光度法测量铂的新体系

本研究工作发现：硫代米蚩酮（ＴＭＫ）可作光度法测定铂（Ⅳ）的新显色剂。与一般光度测铂方法不同，在最佳条件（１ｍＬ１％乳剂ＯＰ，２ｍＬ ｐＨ２．２邻苯二甲酸氢钾－盐酸缓冲溶液，１．２ｍＬ ０．５ｍｇ／ｍＬ ＴＭＫ乙醇溶液存在）下，只需在室温放置２０ｍｉｎ即显色完全，灵敏度高（ε＝１．６９×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１），对比度大（Δλ＝９５ｎｍ），线性范围较范围（５１０～５８０ｎｍ）符合吸光     

2-(3,5-二氯-2-吡啶偶氮)-5-二甲氨基苯胺与铂(Ⅳ)显色反应的研究

研究了２－（３，５－二氯－２－吡啶偶氮）－５－二甲氨基苯胺（３，５－ｄｉＣｌ－ＰＡＤＭＡ）与铂（Ⅳ）的显色反应及铂配合物的质子化行为。结果表明，在０．０４～０．４８ｍｏｌ／Ｌ的Ｈ２ＳＯ４溶液中，于加热的条件下，试剂可与铂（Ⅳ）形成稳定的１∶２绿蓝色ＰｔＬ２Ｈ２＋２配合物，其最大吸收波长位于６３４ｎｍ，表观摩尔吸光系数为９．７３×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，桑德尔灵敏度为０．００２μｇ·ｃｍ－２。铂配合物的三级质子化常数分别为：ｌｇＫａ１＝３．９１，ｌｇＫａ２＝－２．２１，ｌｇＫａ３＝－３．３７。较大量的常见金属离子及除钯、钌外的其它贵金属离子不干扰测定。利用Ｐｔ，Ｐｄ与试剂反应所需的温度差异，可以用差减法消除微量Ｐｄ的干扰．铂（Ⅳ）浓度在每１０ｍＬ０～７．５μｇ范围内符合比尔定律。所拟方法用于二次合金管理样－８８及催化剂中微量铂的测定，结果满意。     

2－（3，5－二氯－2－吡啶偶氮）－5－二甲氨基苯胺与铂（Ⅳ）显色反应的研究

研究了２－（３，５－二氯－２－吡啶偶氮）－５－二甲氨基苯胺与铂（Ⅳ）的显色反应，在ｐＨ３．５～６．０醋酸－醋酸钠介质中，沸水浴加热２５ｍｉｎ，试剂与铂（Ⅳ）形成１：４的紫色配合物，再提高酸度至２．９～４．０ｍｏｌ／Ｌ盐酸溶液，其最大吸收峰红移至６３０ｎｍ，灵敏度显著提高，表现摩尔吸光系数ε＿（６００）＝７．０×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），铂含量在０～３２μｇ／２５ｍＬ范围内符合比耳定律。大多数常见金属离子不干扰测定，所拟方法操作简便，用于催化剂中微量铂的测定，结果满意     

安替比林基重氮氨基—2,4—二硝基苯与汞（Ⅱ）的显色反应及其应用

本研究了试剂安替比林基重氮氨基－２４－二硝基苯（ＡＰＤＮＢＴ）与汞的显色反应，在Ｔｗｅｅｎ－８０存在下和ｐＨ＝１０．２～１２．３的缓冲溶液中，ＡＰＤＮＢＴ与汞生成黄色络合物，其络合比为Ｈｇ∶ＡＰＤＮＢＴ＝１∶２，建立了以４４５ｎｍ为参比波长，５３８ｎｍ为测量波长的双波长分光光度法，其表观摩尔吸光系数为２．１×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，线性范围是０     

2－（5－Br－2－吡啶偶氮－5－二乙氨基）－酚与铑的显色反应的研究及应用

本文研究了２－（－５－Ｂｒ－２吡啶偶氮－５－二乙氨基）－酚与铑（Ⅲ）的显色反应。在ｐＨ为４．０的邻苯二甲酸氢钾缓冲液介质中，Ｒｈ（Ⅲ）与试剂形成稳定的橙红色络合物，其组成比为１：４，最大吸收波长为４９０ｎｍ，表现摩尔吸光系数为１．３×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）。铑含量在０～４μｇ／１０ｍＬ范围内服从比尔定律。     

新显色剂2－（5－硝基－2－吡啶偶氮）－5－二甲氨基苯胺与钯显色反应的研究及其应用

用新合成的偶氮试剂２－（５－硝基－２－吡啶偶氮）－５－二甲氨基苯胺（５－ＮＯ＿２－ＰＡＤＭＡ）研究了光度法测定他的反应条件。结果表明，在０．４５～１．２ｍｏｌ／Ｌ盐酸介质中，钯与试剂形成稳定的蓝色配合物，其最大吸收波长位于６２１ｎｍ处，表观摩尔吸收系数为９．４×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），配合成的组成为Ｐｄ：５－ＮＯ＿２－ＰＡＤＭＡ＝１：２，钯浓度在０～１０μｇ／１０ｍＬ范围内符合比尔定律。本方法是目前测定钯的高灵敏度和高选择性体系之一。用于含钯分子筛及二次合金管理样－８８中微量钯的测定，结果满意。     

2－（4－苯基－2－噻唑偶氮）－5－［（N，N－二羧基甲基）氨基］苯甲酸的合成及其与钯应用的研究

本文报道了新试剂２－（４－苯基－２－噻唑偶氮）－５－［（Ｎ，Ｎ－二羧基甲基）氨基］苯甲酸的合成及其与金属离子的显色反应。详细讨论该试剂与钯显色反应的最适条件，在酸性条件下，试剂与钯形成２：１蓝色络合物，其稳定常数Ｋ＿稳＝５．３９×１Ｏ￣（１１），采用双波长法测定，络合物的摩尔吸光系数ε＿（６７６．４－４８６．０）＝５．６１×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），比单波长测定的灵敏度（ε＿（６７６．４＝３．５８×１０￣４）提高了５７％。试剂的灵敏度高，选择性好，可直接用于铂－钯催化剂中微量他的测定，结果满意。     

用钼酸盐和罗丹明B光度法测定铂

本文研究了在聚乙烯醇（ＰＶＡ）存在下用钼酸盐和罗丹明Ｂ（ＲＢ）光度法测定铂，铂（Ⅳ）与相酸铵和罗丹明Ｂ形成离子缔合物，它的最大吸收波长位于５７０ｎｍ处；摩尔吸光系数６值为６．８３×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），铂量在０～３．５μｇ／２５ｍＬ范围内服从比耳定律，缔合物至少稳定１月。报告了４１种共存离子的影响，除生成杂多酸元素和Ａｕ（Ⅲ）、Ｏｓ（Ⅷ）、Ｒｕ（Ⅲ）外，大多数元素不干扰。测定铂（Ⅳ）的适宜条件为［ＨＣｌＯ＿４］＝０．９３ｍｏｌ／Ｌ，［ＲＢ］＝４．２×１０￣（－５）ｍｏｌ／Ｌ，ＰＶＡ０．８ｇ／Ｌ，本法已用于催化剂和某些铂矿中铂的测定，结果满意。缔合物的摩尔比为Ｐｔ（Ⅳ）：ＲＢ＝１：２，初步探讨了反应机理。     

铬（Ⅵ）与5－溴水杨基荧光酮的显色反应及应用

本文研究了Ｃｒ（Ⅳ）与５－溴水杨基荧光酮（５－Ｂｒ－ＳＡＦ）的显色反应。在ｐＨ６．０ＫＨ＿２ＰＯ＿４－ＮａＯＨｉＬ冲溶液中，Ｃｒ（Ⅳ）与５－Ｂｒ－ＳＡＦ、ＣＴＭＡＢ形式稳定的三元络合物，其最大吸收波长为５７２ｎｍ，表现摩尔吸光系数为１．４２×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）。Ｃｒ（Ⅳ）浓度在０～２．５μｇ／１０ｍＬ间服从比耳定律。用此法测定了环境水样中微量Ｃｒ（Ⅳ），获得满意结果。     

镍（Ⅱ）与2－（5－溴－2－吡啶偶氮）－5－二甲氨基苯胺显色反应的研究及铝合金中镍的测定

本文研究了新显色剂２－（５－溴－２－吡啶偶氮）－５－二甲氨基苯胺与镍（Ⅱ）的反应条件。试验结果发现，在阴离子表面活性剂十二烷基硫酸钠存在下，在ｐＨ５．２～６．５范围内，试剂与镍（Ⅱ）形成稳定的２∶１配合物。其最大吸收波长在５７０ｎｍ处，表观摩尔吸光系数为１．２４×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）。镍（Ⅱ）浓度在０～０．４μｇ·ｍＬ￣（－１）之间符合比尔定律。以硫脲和氟化按作掩蔽剂，可消除Ｃｕ￣（２＋）、Ｐｄ￣（２＋）、Ｆｅ￣（３＋）等离子的干扰。所拟方法用于铝合金中微量镍的测定，结果满意。     

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.     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

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。     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

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.

     

Investigation of Kinetics of Solid-Phase Synthesis of Lithium Orthosilicate

The kinetics of the interaction between lithium carbonate and silica with various degrees of dispersion was investigated by TG and DTA methods. It was found that the utilization of pyrogenic silica with a specific surface area of about 300 m²g^-1 instead of aerosil with one of 175 m²g^-1 leads to an increase of the reaction rate between lithium carbonate and silica, which depends on the formation and growth of lithium orthosilicate crystals in the first stage, and is conditioned by the diffusion of lithium and oxygen ions through the lithium orthosilicate layer formed at temperatures above 800 K. This supposition is supported by the kinetic analysis results obtained with the use of the different models. The optimal regime of heating is recommended. This revised version was published online in July 2006 with corrections to the Cover Date.     

小环化合物中饱和碳质子化学位移的计算

小环化合物由于其张力、构型、构象和各向异性效应等原因,环碳上质子化学位移缺乏规律性,难以预测,对此作者曾提出一种近似算法。本文根据303种小环化合物中饱和碳质子的化学位移实验数据,将适于计算这类质子化学位移的公式表述为:     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。     

结合实际发展电化学科学─—武汉大学电化学研究室工作简介

结合实际发展电化学科学─—武汉大学电化学研究室工作简介查全性,陆君涛（武汉大学化学系电化学研究室,武汉４３００７２）在物理化学的众多分支学科中,电化学长期保持良好的发展势头。除了电化学所研究的体系（溶液、电极／溶液界面等）具有广泛的基础意义外,促使电...