中药片仔癀,六味地黄丸中的微量铬,铅和镉石墨炉原子吸收法测定

本文采用ＧＦ－ＡＡＳ加平台技术，基体改进剂，测定了中药片仔癀，六味地黄丸中铬、铅和镉的含量，铬、铅和镉的线性范围分别为０－０．８ｎｇ／ｍＬ，０－５０ｎｇ／ｍＬ，０－５ｎｇ／ｍＬ，回收率分别为１０２－１０３％，９９－１０１％，９７．５－９８％，本方法简便快速、准确。     

Rapid and sensitive spectrofluorimetric determination of trace amounts of Hg(II) with o-vanillin-8-aminoquinoline

The fluorimetric determination of mercury ions with o-vanillin-8-aminoquinoline (OVAQ) in aqueous solutions was investigated. Hg(II) could react with the fluorescent reagent OVAQ (λ_ex/em = 278/314 nm) to form a nonfluorescent complex in an ethanol-water medium of pH 6.00. The linear range of the proposed method was from 2.5 to 80 μg/L, and the detection limit was 0.80 μg/L. The interferences of 24 foreign ions were also studied. The method was successfully applied to the determination of Hg(II) in sludge. The text was submitted by the authors in English.     

Tetrachloroferrate(III)-selective liquid membrane electrode based on crystal violet

An extract of crystal violet-tetrachloroferrate(III) in nitrobenzene was used to prepare a tetrachloroferrate(III)-selective liquid membrane electrode with a poly(vinyl chloride) support. The optimal conditions to determine 2.5 × 10^–5 – 5.0 × 10^–2 M iron(III) as tetrachloroferrate(III) (anionic slope 56 mV/decade, detection limit 7.9 × 10^–6 M) were found to be 4.0–5.5.M total chloride in 0.75–1.5M hydrochloric acid. The electrode was reliably applied to determine iron in human blood, haematite and mineralized vitamin syrup by direct potentiometry, standard and sample additions as well as standard subtraction techniques.     

Simultaneous Spectrophotometric Determination of Group B Vitamins Using Parallel Factor Analysis: PARAFAC

In this work, a simple and rapid analytical procedure was applied for simultaneous determination of folic acid (vitamin B₀), thiamin (vitamin B₁), riboflavin (vitamin B₂) and pyridoxal (vitamin B₆) based on the absorbance data in the pH range 2.0‐12.0 at 25 °C using parallel factor analysis (PARAFAC). The effect of the pH as the most important factor on the sensitivity of the determination was studied. The spectral data were recorded in 400‐650 nm intervals and a 2‐12 pH range for all four vitamins. The calibration set was constructed in the concentration ranges of 4‐22, 1‐20, 6‐26, and 4‐20 μg mL^?;1 for B₆,B₂,B₁ and B₀, respectively. The root mean squares errors of prediction for the prediction set, (RMSEP), are 0.65, 0.63, 1.13 and 0.34 for B₀,B₁,B₂ and B₆, respectively. The recovery percent for the validation set are in the range of 90.6 to 107.0%. The effect of the experimental conditions and diverse species were discussed. The optimum values of these factors were searched according to the relative standard deviation of the prediction set of mixtures solutions.     

流动注射光度法同时测定铜基合金中的铝和铁

提出了同时测定铜基合金中铝和铁的流动注射分析法。以０．０４ｍｏｌ／ＬＨＣｌ作载液，铬天青Ｓ为显色剂，通过测定６２８ｎｍ处铝、铁两配合物的吸光度之和及铝配合物的吸光度，实现了两组分的同时测定。在优化的实验条件下，检测限：Ａｌ和Ｆｅ分别为１．６９×１０－３和１．７３×１０－３ｍｇ／Ｌ，Ａｌ浓度在０～０．８ｍｇ／Ｌ；Ｆｅ浓度在０～１．０ｍｇ／Ｌ时服从比耳定律。进样频率为６０样／ｈ，所拟方法用于实际样品分析，获得满意结果。     

Spectrophotometric determination of copper after adsorption of its 1-phenyl-4,4,6-trimethyl(1H, 4H)-pyrimidine-2-thiol complex onto microcrystalline naphthalene

A selective Spectrophotometric method has been developed for the trace determination of copper after adsorption of its 1-phenyl-4,4,6-trimethyl(1H, 4H)-pyrimidine-2-thiol (PTPT) complex onto microcrystalline naphthalene. The complex is quantitatively adsorbed on naphthalene in the pH range 7.5–11.5, separated by filtration, dissolved in dimethylformamide (DMF) and determined spectrophotometrically at 400 nm. Beer's law is obeyed in the concentration range 2.5–37.5 g of copper in 10 ml of DMF. The molar absorptivity and Sandell's sensitivity are 1.30 × 10⁴1 · mol^–1 · cm^–1 and 0.0048g cm^–2, respectively. Ten replicate analyses of a solution containing 20.0 g of copper gave a mean absorbance of 0.410 with a relative standard deviation of 0.91 %. The interferences of various ions have been studied and the method has been validated by the determination of copper in various standard reference materials, beers, wines, human hair, goat liver and environmental samples.On leave from St. Stephen's College, Delhi 110 007, India     

原子发射光谱法间接测定黄连素片剂中盐酸小檗碱的研究

本文提出了离子对-原子发射光谱间接测定黄连素片剂中盐酸小檗碱的新方法。发现用1,2-二氯乙烷作萃取剂效果最佳。用此怯测定实际样品的结果与药典法一致,相对误差为0.61％,单一测定的相对标准偏差为0.67％。本法还可在盐酸普鲁卡因共存下单独测定盐酸小檗碱。方法可靠、适用,选择性较好。     

O. Carboxyphenylhydrazoethylacetoacetate as an Analytical Reagent for the Determination of Cu(II) and Co(II) in Complex Materials

An extraction‐spectrophotometric method for the determination of trace amounts of copper and cobalt based on their extraction into n‐pentanol with 0. carboxyphenylhydrazoethylacetoacetate (O.CPHEAA) was per formed. Copper was extracted from pH 6.0 – 8.0 and ionic strength 0.5 M – KCl. The maximum absorption of the extracted Cu(II) ‐ O.CPHEAA complex (1:1 & 1:2 species) occurs at 415 nm. The proposed method succeeded in as saying a concentration of 3–63 μg per 10 mL of n‐pentanol (? = 1.25 × 10⁴L mol^?1 cm^?1). The method failed to ex tract cobalt ion into various organic sol vents over a pH range of 2–11. The suggested method is highly selective and sensitive according to a wide scheme of interference studied. Copper in some plant samples was accurately estimated using the suggested method. The obtained results and the results of the AAS method were consistent. The reproducibility test shows a relative standard deviation of 1%. Sandell sensitivity for A = 0.001 is 5 × 10^?3 μg cm^?2.     

Selective Determination of Trace Mercury (II) after Preconcentration with 4-(2-Pyridylazo)-Resorcinol-Modified Nanometer-Sized SiO2 Particles from Sample Solutions

A rapid, selective method that utilize 4-(2-Pyridylazo)-resorcinol (PAR)-modified nanometer SiO₂ (nanometer SiO₂–PAR) as a new solid-phase extractant for preconcentration of trace mercury (II) has been developed. The adsorption property of nanometer SiO₂–PAR for metal ions was studied by selectively extracting different metal ions from aqueous solutions. The results revealed an excellent affinity of the nanometer SiO₂–PAR for mercury (II) in presence of interfering metal ions at pH 4. The main parameters of solid-phase extraction such as shaking time, elution and sample dilution effect were studied. The extractant shows rapid kinetic sorption, and the adsorption equilibrium of mercury (II) on nanometer SiO₂–PAR was achieved in less than 2 min. The adsorbed mercury (II) was easily eluted by 4 mL of 6 mol L⁻¹ HCl. The maximum preconcentration factor was 50. The maximum static adsorption capacity was 276 μmol g⁻¹ at pH 4. The detection limit (3σ) was 0.43 μg L⁻¹ for cold vapor atomic absorption spectrometry (CVAAS), and the relative standard deviation of the eight replicate determinations was 2.4% for the determination of 2.0 μg of Hg(II) in 100 mL water sample. The method was applied to the determination of trace mercury (II) in sample solutions with satisfactory results.     

比值光谱导数法同时测定铝合金中铁,铜,锌

用比值光谱－导数分光光度法，在ｐＨ５．５缓冲溶液中，利用金属－２－（５－溴－２－吡啶偶氮）－５－二乙氨基酚（５－Ｂｒ－ＰＡＤＡＰ）－ＯＰ三元络合物显色体系，对混合物中铁，铜，锌三组分进行了同时测定。合成试样５次测定回收率在９７．３％－１０４．４％之间。应用于铝合金中铁，铜，锌的测定，各６次测定的ＲＳＤ分别为３．６６％，１．３８％，２．０３％。