双波长分光光度法测定湿法炼锌净化液中的痕量锗

选择水杨基荧光酮－乳化剂ＯＰ－盐酸为显色体系，应用双波长分光光度法扣除硫酸锌的基体干扰，不分离直接测定了湿法炼锌过程中硫酸锌净化液中的痕量锗。测定范围在０－４０ｍｇ／Ｌ。本法应用于株洲冶炼厂锌净化液中锗的测定，结果与该厂长期的萃取－比色法结果相吻合，而测定速度较萃取－比色法至少提高了一倍。     

Determination of Sulphate by Titrimetric and Colorimetric Measurement of Equivalent Displaced Zinc Ion

Abstract

Two methods are described for the determination of sulphate in the range of 200 μg to 100 mg by dissolving precipitated barium sulphate in excess of EDTA at pH 12.5. A titrimetric procedure involves back titration of excess EDTA with a standard zinc solution, while a complementary spectrophotometric method makes use of the stability of the barium EDTA complex in the presence of an excess of zinc ions; the latter are reacted with zincon and are equivalent to the amount of sulphate present.     

New Spectrophotometric Method for Azithromycin Determination

Abstract

Azithromycin (AZT), an antibiotic belonging to the family of macrolides, can be analyzed by a new spectrophotometric method based on the formation of an ion pair between this drug and an inorganic complex of (Mo(V)–thiocyanate) followed by its extraction with dichloroethane. This ion‐association complex shows an orange color and exhibits a maximum absorbance at 469 nm. The experimental conditions of the reaction were studied and optimized. The calibration graph was linear (r=0.9996) over the range 10^?6 M–10^?5 M of AZT. This simple and validated method has been successfully applied to the determination of azithromycin in pharmaceutical formulations with a mean relative standard deviation of 1.07% and mean recovery of 99.66%. The common excipients present in azithromycin formulations did not interfere in its determination. This new spectophotometric method has been applied successfully to illustrate the dissolution profiles of original tablets and generic compounds; hence, it could be employed in routine quality control of azithromycin in pharmaceutical dosage forms.     

流动注射电化学发光分析法测定间苯三酚

基于间苯三酚对鲁米诺在铂电极上弱的电氧化发光信号的强增敏作用与流动注射技术的结合 ,建立了一种测定间苯三酚的电化学发光新方法。该法测定间苯三酚的检出限为 1.2× 10 - 4g L ;线性范围为 4 .0× 10 - 4～ 4 .0× 10 - 2 g L ;相对标准偏差为 4 .7%。     

间苯三酚的合成研究进展

综述了间苯三酚的合成方法及最新研究进展。参考文献24篇。     

对氯苯重氮氨基偶氮苯分光光度法测定微量汞

研究了对氯苯重氮氨基苯偶氮苯 (p -CBDAA)与Hg (Ⅱ )的显色反应 ,在非离子表面活性剂OP存在下 ,在pH 9 5的硼砂缓冲介质中 ,Hg (Ⅱ )与P -CBDAA形成 1∶2的橙红色稳定络合物 ,其λmax=5 3 0nm ,ε=1 2 0× 1 0 5L·mol- 1·cm- 1,汞含量在 0～ 0 8μg/mL范围内遵守比尔定律。方法用于废旧钮扣电池和自来水中汞的测定 ,结果令人满意。     

Spectrophotometric and First Derivative Spectrophotometric Determination of Magnesium with 1-Hydroxy-2-Carboxyanthraquinone

Abstract

1-Hydroxy-2-carboxyanthraquinone reacts with magnesium in ethanol-water mixtures to form a red complex having an absorption maximum at 490 nm in alkaline medium. A detailed study of the characteristics of this complex has been carried out and a spectrophotometric method for the determination of magnesium at the 0.4–4.0 μg ml^?1 level is proposed. The method has been sensitized by employing first derivative spectrophotometry. By the use of the derivative approach magnesium can be determined between 0.08–0.40 μg ml^?1. Statistical analysis of the results is also described.     

二溴羧基偶氮胂催化光度法测定痕量钴

研究了在硼砂 -氢氧化钠缓冲介质中 ,痕量钴 (Ⅱ )与三乙醇胺协同催化H2 O2 氧化二溴羧基偶氮胂褪色的最佳条件。λmax=5 70nm ,表观摩尔吸光系数为 3 7× 1 0 4 L·mol- 1·cm- 1,线性范围 1 5～ 4 0 μg/2 5mL。方法已用于茶叶中痕量钴的测定。     

三异丙苯氧化法制备间苯三酚

以1,3,5-三异丙基苯(TIP)为原料,经初级氧化、二次氧化及酸分解合成了间苯三酚(1)。各步反应的较适宜条件为:初级氧化:TIP340g,氧气压力3.0MPa,于95℃反应28h～38h,4种三羟基氧化物的总收率为60%;二次氧化:以H2SO4/H2O2为氧化剂,甲苯为溶剂,于60℃反应2h,1,3,5-三[(2-羟过氧基)-2-甲基]乙基苯(THPO)的收率为77%;酸分解:以杂多酸为催化剂,丙酮为溶剂,于60℃反应2h,1收率85%(纯度99%)。     

Spectrophotometric Determination of Thyroxine Sodium with p-Benzoquinone

Abstract

A simple, sensitive and selective spectrophotometric method has been developed for the determination of thyroxine sodium. It is based on a reaction with excess of p-benzoquinone in ethanol (95%) whereby 1:1 (thyroxine sodium: quinone) coloured product is obtained, which has an apparent molar absorptivity of 2.911 × 10₃ 1mol_?1 and Beer's law is obeyed over the range of 40–200 μg.ml_?1. When applied to tablets labelled to contain 100 μg, the proposed method gave mean recoveries of 99,13 ± 0.36% for different amounts of added authentic drug.     

亚甲紫分光光度法测定微量亚硝酸根

研究了在盐酸介质中微量亚硝酸根与亚甲紫发生的重氮化反应,建立了测定微量亚硝酸根的新方法。方法的线性范围为８－４４０μｇ／Ｌ ＮＯ＾－２,检出限为８μｇ／Ｌ ＮＯ＾－２方法已用于水中微量亚硝酸根的测定,并对反应机理了初步讨论。     

4,5—二溴苯基荧光酮光度法测定钇

研究４，５－二溴苯基荧光酮灵敏光度法测定钇。在ｐＨ５．５缓冲溶液中钇与ＤＢＰＥ形成橙红色络合物，最大吸收波长位于５５０ｎｍ，表观摩吸光系ε值１．５３×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，钇量在每２５ｍＬ０－８μｈ范围内服从比耳定律，测定极限６．８μｇ／Ｌ，对于钇０．２４ｍｇ／Ｌ测定的相对标准偏差为２．６％，络合物的摩尔组成为Ｙ：ＤＢＰＦ＝１：３。方法用于镁合金和地质标样中钇的测定，结果满意。     

Spectrophotometric Determination of Steroid Oximes

Abstract

A spectrophotometric procedure for the determination of steroid oximes is described utilizing 11β-hydroxy-iia-methyl-5β-pregnane -3, 20 -dione dioxime (I) and iia-hydroxy-progesterone dioxime (II) as models. The method is based on (a) acid hydrolysis to release hydroxylamine, (b) oxidation of hydroxylamine to nitrous acid with iodine, (c) diazotization of sulfanilic acid with the nitrous acid, (d) coupling of the diazonium compound with N-(i-naphthyl)-ethylenediamine dihydrochloride, and (e) measurement of the azo dye at 550 nm. A stoichiometric yield of hydroxylamine is obtained. Analyses of I and II have given typical recoveries (mean ± S. D.) of 99.5 ± 1.1% and 97.8 + 3.5%, respectively. The method is sensitive to ≥ 0.3 × 10^?5 M dioxime.     

紫外分光光度法测定水中硫酸盐

硫酸盐的分析方法较多,本法用紫外分光光度法测定水中硫酸盐。结果表明,方法适合于较清洁环境水样和饮用水的分析,回收率在94％～110％之间,分析指标符合水质分析要求。     

Preconcentration and Spectrophotometric Determination of Chromium (VI) and Total Chromium in Drinking Water by the Sorption of Chromium Diphenylcarbazone with Surfactant Coated Alumina

Abstract

A simple and inexpensive method for determining chromium (VI) in drinking water by spectrophotometry after preconcentration with sodium dodecyl sulphate (SDS) coated alumina column is described. Chromium(VI) is reacted with diphenylcarbazide (DPC) and the Cr-DPC complex is quantitatively adsorbed onto a SDS coated alumina column from 800 ml of sample solution. The complex is then eluted with a 8 ml mixture of methanol, acetone and hydrochloric acid and determined by spectrophotometry. Total chromium can be determined after oxidation of chromium (III) to chromium (VI) by KMnO₄. The relative standard deviation (10 replicate analyses) at the 10 μg l^?1 of chromium (VI) and 10 μg l^?1 of total chromium were 3.5% and 3.4% and corresponding limits of detection (based on 3 σ) were 0.040 μg l^?1 and 0.033 μg l^?1, respectively.     

在线预浓缩FIA比浊法测定水中微量硫酸根

在线预浓缩ＦＩＡ比浊法测定水中微量硫酸根李俊锋，郭如江，赵楠，李绍民（长春地质学院应用化学系长春１３００２６）（吉林大学环境科学系）关键词在线预浓缩，ＦＩＡ，硫酸根流动注射比浊法测定微量硫酸根已有报道［１，２］，由于干扰组分的作用使得前处理操作麻烦，...     

催化动力学光度法测定微量硒的研究

在pH 9.56的NaBH4-NaOH缓冲溶液中,Se(Ⅳ)催化亚甲基蓝(Methylene Blue)氧化硫离子褪色,由此建立了测定硒的动力学光度法,并确定了反应的最佳条件。结果表明,测定Se(Ⅳ)的线性范围为0~0.18μg/L,检测下限为22μg/L,方法应用于魔芋飞粉中硒含量的测定,简单快速,结果令人满意。     

用铁氰化钾分光光度法测定头孢噻肟钠

建立了以铁氰化钾测定头孢噻肟钠的分光光度法。 在0.20 mol/L NaOH溶液中,头孢噻肟钠(CTX)于100 ℃水浴中降解生成的巯基化合物能将Fe(Ⅲ)(pH=3.0)还原为Fe(Ⅱ),根据Fe(Ⅱ)与K3[Fe(CN)6]反应生成可溶性普鲁士蓝(KFeⅢ[FeⅡ(CN)6])的吸光度,可以间接测定头孢噻肟钠的含量。 头孢噻肟钠在0.040~24 mg/L范围内与吸光度(A)呈线性关系,线性回归方程:A=0.05088+0.2166ρ(mg/L),相关系数R=0.9986,检出限为0.01 mg/L,相对标准偏差(RSD)为1.36%(n=11),表观摩尔吸光系数ε=2.3×105 L/(mol·cm)。 此方法可用于药物及血清中头孢噻肟钠含量的测定。     

钕-依诺沙星-十六烷基三甲基溴化铵体系导数光度法测定钕

详细研究了钕 依诺沙星 (ENX) 十六烷基三甲基溴化铵 (CTMAB)体系的常规吸收光谱和导数吸收光谱性质 ,发现阳离子表面活性剂对Nd ENX体系吸收强度有增强作用。采用二阶导数光谱不仅消除了有关干扰 ,而且灵敏度较常规光谱法提高了 7.2倍。探讨了利用该体系以二阶导数分光光度法测定钕的最佳条件及影响因素。在最佳实验条件下 ,Nd的浓度在 1.2× 10 - 5～ 2 .7× 10 - 4mol L范围内与体系吸光度的二阶导数呈线性关系 ;检测限为 1.0 4× 10 - 5mol L(S N =2 )。利用该体系对稀土样品中的钕含量进行了测定 ,结果令人满意。