Determination de l'etain dans les sediments et les boues de stations d'epuration par spectrometrie d'absorption atomique avec generation d'hydruresDetermination of tin in sediments and sewage sludges by atomic absorption spectrometry with hydride generation.

The conditions for the determination of tin in sediments and sewage sludges by atomic absorption spectrometry with hydride generation are evaluated. Hydride generation is achieved in a 0.4 M nitric acid/0.2 tartaric acid solution. The effects of hydrochloric, nitric, sulfuric and hydrofluoric acids are discussed. Matrix effect and interferences from other trace elements are studied. Seven sample decomposition procedures are compared. Refluxing with a (1 + 3) niric acid/hydrochloric acid mixture was the preferred procedure for decomposing such samples.     

New convenient dissolution of iron-rhodium alloys using hydrochloric acid containing a small amount of nitric acid without heating for an ICP-AES analysis.

A new convenient dissolution method for Fe-Rh alloys has been developed. Aqua regia has been used for the dissolution of rhodium alloy samples. However, it is difficult to dissolve high-concentration rhodium (more than 50 mass%) in aqua regia, because a rhodium-passivity on the alloys surface occurs with nitric acid. By using hydrochloric acid containing a small volume of nitric acid, Fe-Rh (24-64 mass%) alloys could be completely decomposed and dissolved under mild experimental conditions. The principal advantages of this method are simplicity and time-saving compared with other dissolution methods.     

Determination of seven trace elements in natural waters after separation by solvent extraction and anion-exchange chromatography

A method is described for the determination of cadmium, cobalt, copper, manganese, lead, uranium, and zinc in samples of natural waters. After acidification with hydrochloric acid the water sample is filtered and the diethyldithiocarbamates of the trace elements are isolated by extraction with acetone—chloroform (2:5) at pH 5. Following this preconcentration step the metal ions are adsorbed on a column of the strongly basic anion-exchange resin Dowex 1-X8 (chloride form) using as sorption solution a mixture (5:4:1, $\text{v}\text{v}$) of tetrahydrofuran, methyl glycol and 6 M hydrochloric acid. Successive elution is effected with 6 M hydrochloric acid (Co, Cu, Mn and Pb), 1 M hydrochloric acid (U) and 2 M nitric acid (Cd and Zn); the metal ions in the eluates are determined by atomic absorption spectrophotometry (except uranium, which is determined fluorimetrically). The procedure was used to determine the trace-metals in water and snow samples collected in Austria and to analyse a sample of sea water from the Adriatic Sea.     

Extraction of copper(II) with the APCD/DIBK system from concentrated hydrochloric and nitric acid media: estimation of true limit of acidity for the extraction

The extraction of copper(II) from strongly acidic solution (0.01-8M hydrochloric and 0.01-5M nitric acid) with ammonium 1-pyrrolidinecarbodithioate in di-isobutyl ketone has been studied. Compared with the hydrochloric acid system, a considerably larger amount of the reagent is needed for complete extraction of copper chelate from nitric acid solution as the extract is more unstable in the nitric acid system. The decomposition of copper chelates extracted from nitric acid is based on the oxidation of the reagent and the chelate; the spectral change of the extract from nitric acid suggests that the copper(II) chelate is initially oxidized to copper(II) and then decomposes. The upper limit of the acidity of both acids from which the copper chelate can be quantitatively extracted strongly depends on the reagent concentration; the limit with 8 x 10(-2)M APCD (500-fold reagent: metal molar ratio) was taken as 8 and 4M for hydrochloric and nitric acid, respectively.     

电感耦合等离子体质谱(ICP-MS)法测定玻纤滤筒中金属元素本底值的预处理方法探讨

探讨了不同预处理方法对国产玻纤滤筒本底值的降低效果,便于废气样品的分析测定。分别对空白滤筒、热硝酸、硝酸+硫酸和硝酸+EDTA、HCl处理后的滤筒进行分析,测得滤筒中金属元素的含量;对处理效果较好的一批滤筒进行空白加标,考察加标回收率,全程用电感耦合等离子体质谱(ICPMS)法对样品进行测定,结果发现空白滤筒中部分金属元素含量较高;热硝酸处理后,滤筒本底中铅含量有所降低,但其它元素去除效果不显著;硝酸+硫酸处理后,滤筒中铅含量剧增;硝酸+EDTA处理滤筒,铅可以得到较好的去除效果,大部分金属元素含量有了明显降低;基于HCl对金属有较好的溶出效果,浸泡可较好地降低滤筒中金属元素的含量,但大量氯离子存在对ICP-MS法测定的干扰较大。对硝酸+EDTA处理后的滤筒进行空白加标,大部分金属元素加标回收率75%。故以硝酸+EDTA处理玻纤滤筒可以使国产玻纤滤筒适用于废气样品的分析。     

Systematic Errors in the Determination of Trace Metals,Part II. Memory Effects of Quartz Vessels Used for Sample Preparation in the Determination of Ultra-Trace Levels of Platinum

The influence of different cleaning procedures applied to quartz vessels used for sample preparation on the Pt contents in blank solutions was studied. The platinum concentration was determined by inductively coupled plasma mass spectrometry. The strong dependence of the memory effect of the quartz crucible on the previously stored Pt content of the sample was observed. It was shown that cleaning a quartz crucible previously used for Pt determinations with hot nitric acid was insufficient. When heating the vessels with a mixture of nitric, perchloric and hydrochloric acid, considerable amounts of Pt are released. In the case of new crucibles, the platinum contents in blanks were very low after cleaning with hot nitric acid.     

The rapid colorimetric determination of molybdenum with dithiol in biological, geochemical and steel samples.

A rapid method for the determination of molybdenum in botanical, biological, geochemical and steel samples with dithiol, is described. Botanical and biological samples are ashed at 550 °C before leaching with 4 M hydrochloric acid, while geochemical samples are fused with potassium hydrogensulphate, and steels are decomposed with nitric and hydrochloric acids. The dithiol complex of molybdenum is formed by the addition of an alkaline solution of dithiol to the sample solution, and then extracted into isoamyl acetate. Ascorbic acid and citric acid are used to eliminate interferences from iron and tungsten, and the addition of potassium iodide gives the procedure very high tolerance to copper. Up to 150 geochemical samples or ashed botanical or biological samples can be analysed per man-day. Sensitivity of the method is 0.05, 0.5 and 10 p.p.m. for biological, geochemical and steel samples, respectively. The relative standard deviation is better than ±7% over the standard range used, and recovery of added molybdenum is complete.     

Application of ion-exchange separations to determination of trace elements in natural waters-IX: simultaneous isolation and determination of uranium and thorium

A method is described for the determination of uranium and thorium in samples of natural waters. After acidification with citric acid the water sample is filtered and sodium citrate and ascorbic acid are added. The resulting solution of pH 3 is passed through a 4-g column of Dowex 1 x 8 (citrate form) on which both uranium and thorium are adsorbed as anionic citrate complexes. Thorium is eluted with 8M hydrochloric acid and separated from co-eluted substances by anion-exchange in 8M nitric acid medium on a separate 2-g column of the same resin in the nitrate form. After complete removal of iron by washing with a mixture consisting of IBMK, acetone and 1M hydrochloric acid (1:8:1 v v ) and treatment of the resin with 6M hydrochloric acid, the uranium is eluted from the 4-g column with 1M hydrochloric acid. In the eluate thorium is determined spectrophotometrically (arsenazo III method) while fluorimetry is employed for the assay of uranium. The procedure was used for the determination of uranium and thorium in numerous water samples collected in Austria, including samples of mineral-waters. The results indicate that a simple relationship exists between the uranium and thorium contents of waters which makes it possible to calculate the approximate thorium content of a sample on the basis of its uranium concentration and vice versa.     

螯合离子色谱法分析复杂基体中痕量金属离子的研究

发展了应用螯合离子色谱法分析复杂基体中痕量金属离子的新方法。针对不同的检测目的,利用螯合柱（ＭｅｔＰａｃＣＣ－１）和浓缩柱（ＴＭＣ－１）,采用适当的洗脱液在线将基体中的阴离子、一价阳离子、碱土金属离子以及其它干扰离子除去,同时,浓缩富集待测的痕量金属离子,然后再选择适当的梯度淋洗体系,在含有双功能基的分析柱上分离Ｐｂ,Ｃｕ,Ｃｄ,Ｃｏ,Ｚｎ和Ｎｉ等过渡金属离子和１４种镧系金属离子,继而用在线柱后衍生和光度法检测。方法简单快速,样品经适当的酸消解成溶液后即可进样,灵敏度高,检测限为１０－９级甚至更低。     

New approach to fabricate nanoporous gold film

A simple preparation of ultrathin nanoporous gold film was described. Copper and gold were used to fabricate Cu-Au alloy film sthrough vacuum deposition. The formation of nanoporous gold films from the alloy films involved thermal process and chemical etch by hydrochloric acid or by nitric acid. The free-standing nanoporous gold films have been analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectrometer (XPS) and surface-enhanced Raman scattering (SERS). It was noted that the nanoporous gold film etched by hydrochloric acid is uniform with a cover of fog-like moieties.     

A comparison of two digestion procedures for the determination of selenium in biological material

Two digestion procedures have been tested on samples of flour, blood and urine for application in the determination of selenium by hydride-generation atomic-absorption spectrometry. The first utilizes a mixture of concentrated nitric, perchloric and sulphuric acids and the second a mixture of magnesium nitrate hexahydrate, concentrated nitric acid and 6M hydrochloric acid. The accuracy of the procedures was tested by analysis of standard reference materials and by comparison with results from neutron-activation analysis. It was found that the "magnesium method" can replace the more common procedure, which includes perchloric acid, for the sample types investigated in this paper.     

Multielemental characterisation of cobalt by glow discharge quadrupole mass spectrometry

Multielemental determination and the assessment of purity of cobalt metal used in the preparation of Ni-based super-alloys have been carried out by glow discharge quadrupole mass spectrometry (GD-QMS). Relative sensitivity factors (RSF) generated from certified iron matrix reference samples (NIST 663 and 664 low alloy steel pin standards) could be used for the determination of different trace element constituents of the sample. Different wet chemical procedures were also carried out for the determination of the trace constituents in the sample. The GD-QMS results are in reasonably good agreement with those obtained from wet chemical procedures, validating the use of the RSF values generated on low alloy steel standards for the computation of trace element concentrations in cobalt metal. A variety of molecular ions formed through the reaction of cobalt (matrix) with the discharge gas (argon) were also detected.     

差示分光光度法测量Cu30W70钨铜合金中钨的含量

采用传统的湿化学差示分光光度分析方法,研究了广泛用于军工、高压开关、电火花电极、电子封装的新型材料钨铜合金中钨含量的定量分析方法。由于该材料的耐腐蚀性,试样溶解是关键,实验表明采用盐酸+硝酸(9+1)、硫酸+磷酸(1+3)混合酸低温加热溶解,测定时加入草酸胺掩蔽铜的干扰,用硫氰酸胺显色。以Cu30W70为例用40%的钨为参比,配制一系列标准溶液制作工作曲线,钨含量在5~10μg/mL内服从比耳定律,方法的相对标准偏差(RSD)为1.6%,加标回收率为101.6%,适用于含钨45%以上的钨铜合金中钨的测定。     

微波消解-电感耦合等离子体原子发射光谱（ICP-AES）法测定镍基耐蚀合金中镍

采用微波消解法与电感耦合等离子体原子发射光谱(ICP-AES)法相结合的方式,建立了镍基耐蚀合金中镍元素含量的测定方法。试样在浓硝酸和浓盐酸中微波消解后,用电感耦合等离子体原子发射光谱仪在优化的工作参数下测定,结果表明,稀释的消解液可直接用于镍含量的测定,光谱干扰少。对镍基耐蚀合金中镍含量进行多次平行测定,相对标准偏差(RSD,n=7)为0.29%,且测得值与标准值结果一致。对不同的镍基耐蚀合金样品进行加标回收实验,加标回收率在98.5%~102%。标准物质验证实验表明,测得值与标准值一致。     

Chemical analysis of manganese nodules : Part II. Determination of uranium and thorium after anion-exchange separation

A method is described for the determination of uranium and thorium in manganese nodules. After dissolution of the sample in a mixture of perchloric and hydrofluoric acids, uranium is adsorbed on the strongly basic anion-exchange resin Dowex 1 (chloride form) from 6 M hydrochloric acid. The effluent is evaporated and the residue is taken up in 7 M nitric acid—0.25 M oxalic acid; thorium is then isolated quantitatively by anion-exchange on Dowex 1 (nitrate form). Thorium is eluted with 6 M hydrochloric acid and determined spectrophotometrically by the arsenazo III method. Uranium is eluted from the resin in the chloride form with 1 M hydrochloric acid and then separated from iron, molybdenum and other co-eluted elements on a column of Dowex 1 (chloride form); the medium consists of 50% (v/v) tetrahydrofuran, 40% (v/v) methyl glycol and 10% (vv) 6 M hydrochloric acid. After removal of iron and molybdenum by washing the resin with a mixture of the same composition and with pure aqueous 1 M hydrochloric acid, the adsorbed uranium is eluted with 1 M hydrochloric acid and determined by fluorimetry. The method was used successfully for the determination of ppm-quantities of uranium and thorium in 60 samples of manganese nodules from the Pacific Ocean.     

Liquid-liquid extraction study of tellurium(IV) with N-n-octylaniline in halide medium and its separation from real samples

N-n-Octylaniline in xylene is used for extractive separation of tellurium(IV) from hydrochloric acid media. Tellurium(IV) is extracted quantitatively with the 3% reagent in xylene from 5.5 to 7.5 M hydrochloric acid. It is stripped from organic phase with 1:1 ammonia and estimated spectrophotometrically with pyrimidine-2-thiol (4'-bromoPTPT). The effects of metal ion, acids, reagent concentration, diluents and various foreign ions have been investigated. The log-log plots of distribution ratio (D(Te(IV))) versus N-n-octylaniline concentration indicate that the nature of extracted species is [(RR'NH(2)(+))(2) TeCl(6)(2-)](org). The method affords binary separation of tellurium(IV) from gold(III), selenium(IV), bismuth(III), copper(II), lead(II), antimony(III), germanium(IV) and is applicable to the analyses of synthetic mixture containing associated metal ions and alloy samples. The method is simple, selective, rapid and accurate.     

Improved separation of cadmium-109 from silver cyclotron targets by anion-exchange chromatography in nitric acid—hydrobromic acid mixtures

A method is presented for improved separation of ¹⁰⁹Cd from silver cyclotron targets. After dissolution of the target material in nitric acid and removal of silver by precipitation with copper metal, at pH 5, the cadmium is separated from zinc, copper and other elements by anion exchange chromatography. The solution in 0.5 M nitric acid plus 0.1 M hydrobromic acid is percolated through a column containing 4 ml of AG1-X8 anion-exchange resin (100–200 mesh), equilibrated with the same acid mixture. Zinc, copper(II) and other elements are eluted with 50 ml of this mixture. Cadmium is retained and finally eluted with 50 ml of 3 M nitric acid. The cadmium is retained much more strongly from the hydrobromic acid mixture than from the 0.02 M hydrochloric acid used for such separations previously; the presence of the strongly absorbed nitrate anion in fairly high concentration completely eliminates the tailing of zinc observed in 0.02 M hydrochloric acid. A typical elution curve and results of quantitative separations are presented.     

火焰原子吸收光谱法测定硒碲混合物中碲的研究

本文建立了酒石酸-硝酸盐酸混酸溶解样品,在王水-酒石酸介质中,采用空气-乙炔火焰在原子吸收光谱仪上测定硒碲混合物中的碲的方法。本实验研究了样品处理方法、乙炔流量、燃烧高度、灯电流、溶液介质等有关工作条件。实验表明碲浓度在1～20ug/mL范围内与吸光度呈良好的线性关系,回归方程为A=0.0229C 0.0009,相关系数0.9998,检出限0.08ug/mL,本方法适合于硒碲混合物中碲的测定,相对标准偏差为0.9%～1.3%,回收率为98%～102%。     

Chemical analysis of manganese nodules. Part I. Determination of seven main and trace constituents after anion-exchange separation

A method is described for the determination of Mn, Cu, Co, Zn, Cd, Pb and U in samples of manganese nodules. After dissolution of the sample in concentrated hydrochloric acid, the elements are adsorbed on a column of the strongly basic anion-exchange resin Dowex 1 from a medium consisting of 50 % (v/v) hexone, 40 % (v/v) isopropanol and 10 % (v/v) 12 M hydrochloric acid. After removal of iron by washing the resin bed with a mixture of the same composition, 6 M hydrochloric acid is passed through the column to elute Mn, Cu, Co, and Pb, and then 1 M hydrochloric acid and 2 M nitric acid to elute Zn, Cd and U. In the eluates the elements are determined by atomic-absorption spectrometry except for uranium which is determined by fluorimetry. The method was used successfully for the determination of mg and p.p.m. quantities of Mn, Cu, Co, Zn, Cd, Pb and U in 17 samples of manganese nodules from the Pacific Ocean.     

Liquid-liquid extractions with metal diethyldithiocarbamates as reagents

The liquid-liquid extraction of about twenty ions with metal diethyldithiocarbamates in chloroform from citrate buffers of pH 2–6 and the most common inorganic acids has been studied. Several backextraction reagents have been examined: hydrochloric acid (1–12M), dilute nitric acid saturated with bromine and a mixture of concentrated hydrochloric acid and hydrogen peroxide. A short review of metal diethyldithiocarbamates as extraction reagents and a mathematical model for these extractions are also included.