新试剂10—（2—羧基苯偶氮）—9—菲酚的合成及与铈显色反应的研究

本文研究新试剂１０－（２－羧基苯偶氮）－９－菲酚（简称ＣＡＰ的合成，测定试剂的高解常数。研究了试剂ＣＡＰ与铈（Ⅳ）的显色反应。在表面活性剂ＯＰ存在下，光度法测定球墨铸铁中铈的含量，结果较满意。     

新显色剂二安替比林基－4－羟基苯基甲烷与铈（Ⅳ）的显色反应

合成了二安替比林基－４－羟基苯基甲烷（ＤＡｐＨＭ）．研究了它与铈（Ⅳ）的显色反应，在稀磷酸介质和Ｔｗｅｅｎ－６０存在下，试剂与铈（Ⅳ）生成橙红色化合物，λｍａｘ＝４５０ｎｍ，ε＝６．８×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，Ｃｅ（Ⅳ）量在０．１～０．８μｇ／２５ｍＬ间符合比尔定律．用于镁合金和锌矿石中微量铈的测定，结果满意     

2－（2－噻唑偶氮）－5－〔N，N－二羧基甲基）氨基〕苯酚的分析特性和钴测定的研究

研究了新显色剂２－（２－噻唑偶氮）－５－［（Ｎ，Ｎ－２羧基甲基）氨基］苯酚（ＴＡＤＣＡＰ）与金属离子的显色反应，着重探讨了试剂与Ｆｅ￣（３＋）、Ｃｏ￣（２＋）、Ｎｉ￣（２＋）、Ｃｕ￣（２＋）、Ｚｎ￣（２＋）、Ｍｎ￣（２＋）显色反应的最佳条件，测定了这些络合物的络合比和稳定常数等，同时建立了钴的分析方法，并用于维生素Ｂ＿（１２）注射液中Ｃｏ￣（２＋）的测定。     

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。     

钴与5－Cl－PADAB反应机理及其应用的研究

对钴与４－［（５－氯－２－吡啶）偶氮］－１，３－二氨基苯（５－Ｃｌ－ＰＡＤＡＢ）形成络合物的吸收光谱进行探讨，结果表明：试剂及络合物在不同酸度条件下形成不同型体。在酸性条件下，络合物为大阳离子，钴离子以三价形式存在，钻与试剂的络合比为１：２。在强酸性介质中，将此络合物用于光度测定钻，方法选择性及稳定性好，且灵敏度极高。对水、粮食、土壤、茶叶及维生素Ｂ＿（１２）中微量钻进行直接测定，获得满意结果。     

RE（Ⅲ）与5－（2＇－羧基苯偶氮）绕丹宁及其衍生物的配合物稳定常数

采用ｐＨ－电位滴定法研究了乙醇溶液中ＲＥ（Ⅲ）与新型荧光试剂Ｈ＿２Ｌ［５－（２＇－羧基苯偶氮）］绕丹宁（ＲＡＣＰ）、５－（４＇－氯代－２＇－羧基苯偶氮）绕丹宁（Ｃｌ－ＲＡＣＰ）、５－（４＇－溴代－２＇－羧基苯偶氮）绕丹宁（Ｂｒ－ＲＡＣＰ）］二元体系，计算了相关平衡常数及在不同ｐＨ条件下各物种之分配比，三种试剂的表现稳定常数大小为ＲＡＣＰ＞Ｃｌ－ＲＡＣＰ＞Ｂｒ－ＲＡＣＰ。而与Ｎｄ（Ⅲ）的累积生成常数ｌｇβｍｌｈ基本相同。同时，研究了浓度对ｌｇβｍｌｈ的影响，测定了１５种稀土与ＲＡＣＰ的ｌｇβｌｈ。发现ｌｇβｍｌｈ随原子序数Ｚ增大变为四组。溶液中各物种分配比的测定表明无ＭＬ＿３生成，其物种分配比随配体与稀土摩尔比的变化而变化，但稀土种类并无影响．     

新荧光试剂3－对甲苯基－5－（2’－羧基苯偶氮）绕丹宁的合成及荧光光度法测定蚕丝制品中痕量铜的研究

本文报道了新荧光试剂３－对甲苯基－５－（２’－羧基苯偶氨）绕丹宁（ＰＭ－ＰＲＡＣＰ）的合成。用元素分析、红外光谱、核磁共振氢谱和质谱确证了其结构，研究了其荧光性质。在ｐＨ５．６时，该试剂与Ｃｕ￣（２＋）形成稳定的荧光螯合物，且在λ＿（ｅｘ）／λ＿（ｅｍ）＝３０５ｎｍ／４０５ｎｍ产生强烈荧光。其荧光强度与Ｃｕ￣（２＋）的浓度在０～１．６μｇ／２５ｍＬ范围内呈线性关系，检测限为５×１０￣（－４）μｇ／ｇ。已用于痕量铜（Ⅱ）的荧光分光光度法测定。测定了蚕茧、蚕丝和丝绸中的痕量铜，结果满意。     

镉（Ⅱ）－1－苯基－3－甲基－4－苯甲酰基－吡唑啉酮－5配合物吸附波的研究

在ｐＨ４．８的ＨＡｃ－ＮＨ＿（４）Ａｃ介质中，Ｃｄ（Ⅱ）与１－苯基－３－甲基－４－苯甲酰基－吡唑啉酮－５（ＰＭＢＰ）生成配合物，于－０．６７Ｖ（ｖｓ．ＳＣＥ）出现一尖锐、灵敏的极谱波。镉含量在０．００１～１．μｇ／ｍＬ范围内与峰高成线性关系。用多种电化学方法研究了极谱波的性质及电极反应机理，证明－０．６７Ｖ处的极谱波为配合物吸附波，峰电流由中心离子Ｃｄ（Ⅱ）还原产生。配合物组成为Ｃｄ（Ⅱ）：ＰＭＢＰ＝１：１。试验了３０多种离子对峰电流的影响，用ＳｒＳＯ＿４共沉淀分离Ｐｂ（Ⅱ），再经巯基棉分离其它干扰离子。用于矿样中镉的测定，结果满意。     

Fe（Ⅲ）－TEA－5－Br－PADAP－H_2O_2体系中催化波的研究及其应

在０．２ｍｏｌ·Ｌ￣（－１）ＮＨ＿４Ｃｌ－ＮＨ＿３·Ｈ＿２Ｏ底液中，（ｐＨ为９．２６），得到一个极为灵敏的Ｆｅ（Ⅲ）－ＴＥＡ－５－Ｂｒ－ＰＡＤＡＰ－Ｈ＿２Ｏ＿２配合吸附催化波，其峰电位为－０．７１Ｖ（ｖｓ．ＳＣＥ）。铁浓度在１．８×１０￣（－１０）～５．４×１０￣（－６）ｍｏｌ·Ｌ￣（－１）范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究，证明是一种配合吸附催化波，并成功地应用于各类水样，钒催化剂中微量或痕量铁的测定。     

新试剂N－烯丙基－N′－（氨基对苯磺酸钠）硫脲（ASATu）的合成、表征及其反应性能的研究

本文报道了新试剂Ｎ－烯丙基－Ｎ′－（氨基对苯磺醚钠）硫脲（ＡＳＡＴｕ）的合成并确定了结构。该试剂与４５种元素在不同介质中反应，仅有Ｃｕ￣（２＋）、Ａｇ￣＋、Ｂｉ￣（３＋）、Ｈｇ￣（２＋）和Ｆｅ￣（３＋）等离子产生特征性反应。实验证明，它可作为Ｃｕ￣（２＋）、Ａｇ￣＋等新的鉴定试剂；在酸性和近中性介质中测定了该试剂与稀土元素等四十多种金属元素反应的摩尔吸光系数。     

Spectrofluorimetric Determination of the Hypertensive Drug Captopril Based on Its Oxidation with Cerium(IV)

A highly sensitive and specific spectrofluorimetric method for the analysis of captopril (CAP) in the pure form and in the tablet dosage forms has been described. The method was based on the oxidation of captopril by cerium(IV) in the presence of sulphuric acid and subsequent monitoring the fluorescence of the induced Ce(III) ion produced at λ_ex = 256 nm and λ_em = 354 nm. All variables affecting the reaction conditions such as cerium(IV) concentration, type and concentration of acid medium, reaction time, diluting solvents, temperature and heating time were carefully studied and optimized. Under the experimental conditions used, an excellent linear relationship was obtained between fluorescence intensity and the concentration of CAP. A linear range of determination was verified for captopril concentrations between 0.1–1.3 μg mL^?1 and the correlation coefficient of determination was 0.9997. Quantitation and detection limits were calculated. The precision of the method was satisfactory; the values of relative standard deviations did not exceed 1.14%. No interference could be observed from the excipients and additives are commonly presented in dosage forms. The proposed method was applied successfully for the assay of the studied drug in pure form and in pharmaceutical dosage forms. Recovery experiments revealed recovery of 99.82–100.21%. The results of the analysis show a good agreement with those obtained by official method stated in the United State Pharmacopoeia.     

Chromatographic separation of cerium(Ⅲ) in L-valine medium using poly[dibenzo-18-crown-6]

A column chromatographic method has been developed for the separation and determination of cerium(Ⅲ) using poly[dibenzo-18-crown-6]. The separation was carried out in L-valine medium. The adsorption of cerium(Ⅲ) was quantitative from 1×10-1 to 1×10-4 mol/L L-valine. Amongst the various eluents, 1.0-8.0 mol/L hydrochloric acid, 1.0-8.0 mol/L hydrobromic acid, 1.0-8.0 mol/L perchloric acid, 1.0-2.0 mol/L sulfuric acid and 4.0-5.0 mol/L acetic acid, were found to be the efficient eluents for cerium(Ⅲ). The capacity of poly[dibenzo-18-crown-6] for cerium(Ⅲ) was (0.428±0.01) mmol/g. The method was applied to the separation of cerium(Ⅲ) from associated elements link uranium(Ⅵ) and thorium(Ⅳ). It was also applied for the determination of cerium(Ⅲ) in geological samples. The method is simple, rapid and selective with good reproducibility (approximately±2% ).     

在L-缬氨酸介质中应用聚二苯并-18-冠醚-6-分离铈（III)

 A column chromatographic method has been developed for the separation and determination of cerium(Ⅲ) using poly［dibenzo-18-crown-6］. The separation was carried out in L-valine medium. The adsorption of cerium(Ⅲ) was quantitative from 1×10-1 to 1×10-4 mol/L L-valine. Amongst the various eluents, 1.0-8.0 mol/L hydrochloric acid, 1.0-8.0 mol/L hydrobromic acid, 1.0-8.0 mol/L perchloric acid, 1.0-2.0 mol/L sulfuric acid and 4.0-5.0 mol/L acetic acid, were found to be the efficient eluents for cerium(Ⅲ). The capacity of poly［dibenzo-18-crown-6］ for cerium(Ⅲ) was （0.428±0.01） mmol/g. The method was applied to the separation of cerium(Ⅲ) from associated elements link uranium(Ⅵ) and thorium(Ⅳ). It was also applied for the determination of cerium(Ⅲ) in geological samples. The method is simple, rapid and selective with good reproducibility (approximately±2%).     

负催化动力学光度法测定痕量铈

在中性介质中 ,Ce( )对过氧化氢氧化结晶紫的反应有较强的负催化作用 ,据此建立了负催化动力学光度法测定痕量铈的方法。方法线性范围为1 .9× 1 0 - 4～ 2 .0× 1 0 - 3μg/m L ,已用于人发和鸡毛中铈的测定。     

Ce(C_8H_8)_2和Ce(C_8H_8)_2~-的化学键性质

结合改进的重叠模型Xa-SW法和Ziegler过渡态法,通过将中心原子与配体的作用选成离子聚集、中心原子只有s和p轨道参与成键、中心原子只有d轨道参与成键、中心原子只有f轨道参与成键、中心原子的s、p、d和f轨道同时参与成键5种类型,从能量角度分析了Ce(C_8H_8)_2和Ce(C_8H_8)~-_2的化学键性质。     

Observation of cerium isotope fractionation in ion-exchange chromatography of Ce(III)-malate complex

The cerium isotope fractionation between Ce(III)-malate complex in aqueous solution and cerium ions in a cation-exchange resin was conducted by displacement chromatography. The pH and the chemical composition of the eluent were optimized for maintaining the self-sharpening band boundaries and the 21 m chromatographic migration of the Ce band underwent. Graphite slurry was coated on the tantalum filament prior to sample loading for reducing the isobaric interferences in cerium isotopic ratio determination by mass spectrometry. From the experimental results, it was found that the heavier isotope was enriched in the front boundary part of the cerium adsorption band, which meant that the heavier isotope was preferentially fractionated into the Ce3+ malate complex rather than simply hydrated Ce3+ ions. The isotope separation coefficient for the 136Ce/140Ce and 142Ce/140Ce was 5.2 x 10(-5) and -1.9 x 10(-5), respectively, at 298 K.     

Molecularly imprinted photonic polymer as an optical sensor to detect chloramphenicol

An inverse opal photonic crystal sensor that could specifically detect chloramphenicol (CAP) in a label-free way was introduced in the current research. A colloidal crystal template was first prepared from monodisperse SiO(2) nanospheres. Precursors with different compositions were infused into the void spaces of the respective templates and aggregated. The template and the imprinted CAP were removed, and a molecularly imprinted photonic polymer (MIPP) with numerous nanocavities derived from the SiO(2) template was prepared. The MIPP could specifically recognize the target CAP. The results showed that the embedding and transporting of CAP could change the reflection peak intensity of the MIPP. The MIPP exhibited good responsiveness, with a detection range from 1 ng mL(-1) to 1 μg mL(-1) of CAP. The MIPP response time was 8 min upon its addition to CAP at a concentration of 10 ng mL(-1), which is shorter than that of other methods. After repeated use, the MIPP maintained a good performance and detection capacity. Thus, the results prove that the novel sensor could specifically detect CAP in a simple, time-saving, and low-cost manner.     

纳米金-二氧化钛纳米针修饰电极用于氯霉素检测

将金胶-TiO2纳米针修饰玻碳(Au-TiO2/GC)电极用于对氯霉素(CAP)浓度的电化学测定。 结果表明,在0.1 mol/L pH=7.0的磷酸盐缓冲溶液(PBS)体系中,CAP在Au-TiO2/GC电极上有较好的电化学响应,CAP浓度在8.0×10-7～1.0×10-4 mol/L范围内,峰电流与其浓度呈良好的线性关系,检出限为7.8×10-8 mol/L。 并对氯霉素滴眼液中CAP浓度进行了检测,发现该方法有高的检测灵敏度、好的重复性和抗干扰性,且操作简便、成本低廉。     

Stopped-flow--photometric and kinetic--fluorimetric methods for the determination of thyroid hormones in tablets

The catalytic effect of thyroxine and triiodothyronine on the reaction between cerium(IV) and arsenic(III) was studied by using photometric and fluorimetric measurements. The kinetic - photometric studies were based on measurement of the decrease in absorbance of cerium(IV), whereas the rate of formation of fluorescent cerium(III) was measured in the kinetic - fluorimetric studies. A modular stopped-flow system was coupled to a spectrophotometer in order to develop stopped-flow methods for the determination of thyroxine and triiodothyronine. The proposed methods were compared and applied to the determination of these hormones in pharmaceutical preparations.     

多壁碳纳米管修饰玻碳电极伏安法测定氯霉素

研究了氯霉素(CAP)在多壁碳纳米管修饰玻碳电极上的电化学行为.发现在pH=2.0的0.1 mol/LKCl-HCl底液中,CAP在该修饰电极上有一灵敏的还原峰(Ep=-0.36 V vs.Ag/AgCl),峰电流与CAP浓度成正比,线性范围为6.0×10-6~2.7×10-4mol/L,检测限达3.0×10-6mol/L.该方法灵敏、准确,用于模拟样品和实际样品的测定,结果满意.