The direct flame photometric determination of Strontium: Calcium ratios in the ash of human bones and teeth

Samples of bone or tooth ash are dissolved in hydrochloric acid and the strontium : calcium ratio is determined directly by flame photometry using an oxygen-propane flame, surrounded by a mantle of oxygen in order to eliminate the suppressing effect of phosphate. The effective concentration range is 20—1000 p.p.m. of strontium with respect to calcium and the standard deviation, which remains constant over this range, is 10 p.p.m. of strontium -with respect to calcium.     

The spectrographic determination of total barium in bone ash

Samples of bone ash are mixed with graphite and anhydrous copper sulphate as spectrographic buffer and lanthanum oxide as internal standard. The mixture is pressed into 30-mg pellets and burnt in a d.c. arc surrounded by a mantle of oxygen and argon. The spectra are evaluated by non-recording microphotometry. The effective concentration range is 2–25 p.p.m. of barium in the ash, and the coefficient of variation is 8% for single exposures at the 8-p.p.m. level     

The determination of strontium in coal ash by atomic absorption spectrophotometry

An atomic absorption spectrophotometric method for the determination of 0.01%–0.40% strontium in coal ashes is proposed. After suitable dissolution of the sample, 2000 p.p.m. of lanthanum are added to overcome interferences before the solution is atomized. The results obtained were compared with those obtained by flame-emission spectrophotometry. The method is rapid and no preliminary separations are necessary.     

Determination of barium and strontium in sea water

A process based on ion-exchange concentration and separation followed by flame photometry has been developed for the determination of strontium and barium at natural levels in sea water. These elements are stripped from 1-I samples of sea water by means of a cation-exchange resin in the calcium form and selectively eluted with CyDTA and EDTA respectively. Factors influencing the intensity of strontium and barium in hydrogen flames have been studied. The standard deviations of the method are 0.05 p.p.m. for strontium and 0.6 p.p.b. for barium and the accuracy of the method is more than sufficient to demonstrate clearly the variability of Sr/Cl and Ba/Cl ratios with depth and location     

The determination of oxygen in silicon by alpha and helium-3 activation analysis

A non-destructive analytical method for oxygen in silicon by both helium-3 and α-particle activation analysis was applied to different samples, containing 0.05–10 p.p.m. of oxygen. The accuracy and precision of the method were studied. For concentrations above 1 p.p.m., the average coefficient of variation is about 6% for α-activation and 13% for helium-3 activation. For concentrations of about 60 p.p.b., the corresponding figure is about 20%. The results of both methods, which agree within 8%, are compared to infrared analysis. The determination limit of the method is 4 p.p.b. for helium-3 activation and 22 p.p.b. for α-activation.     

Determination of magnesium in iron by atomic absorption spectrophotometry

An atomic absorption spectrophotometric method for the determination of 0.001–0.10% magnesium in irons has been proposed. After suitable dissolution of the sample, 1500 p.p.m. of strontium is added to suppress aluminium interference and the solution is atomised in an atomic absorption spectrophotometer. The method is rapid, has high sensitivity, is free from interference and no preliminary separations are required.     

Direct determination of parts-per-billion levels of germanium in botanical samples and coal fly ash by graphite furnace atomic absorption spectrometry

 Parts-per-billion levels of germanium can be determined directly by graphite furnace atomic absorption spectrometry (GFAAS) using palladium plus strontium as a mixed modifier resulting in pyrolysis temperatures up to 1400 °C without loss of germanium. At this temperature the matrix effect including the most troublesome sulfate interference can be eliminated. Palladium plus strontium nitrate is advantageous compared to palladium alone or palladium plus magnesium nitrate; an amount of 15 μg of sulfate does not show any interference on the determination of 1 ng of germanium. The method was successfully applied to the determination of ng/g levels of germanium in botanical samples and coal fly ash after thermal decomposition of the samples in a mixture of acids using a pressure bomb. The results were consistent with the reference values given for botanical samples and coal fly ash with a recovery range of 96.4∼103.4% Received: 16 September 1996/Revised: 10 December 1996/Accepted: 14 January 1997     

15％哒螨灵乳油的气相色谱测定分析

采用气相色谱分析法,以实验室较常用AgilentDB -1毛细管色谱柱为分离柱,选择氢火焰离子化检测器,建立一种适合实验室开展哒螨灵质量分数检测的分析方法,经保留时间定性确证,峰面积外标法进行定量分析.结果表明,哒螨灵的线性相关系数为0.99913;变异系数为0.21％;平均回收率为98.38％.     

Indirect flame photometric determination of sulphate ions

In this paper the possibilities have been studied of determining sulphate ions by indirect flame photometry by difference. Barium and Strontium in constant concentration were used as background elements. By means of the methods proposed sulphate ions can be determinined in the concentration range 0 to 70 p.p.m. with barium and 0 to 110 p.p.m. with strontium. The determinations can be carried out in dilute solutions of alkali metal sulphates and sulphate ions can also be estimated in the presence of macroquantities of other compounds. This may prove useful for the quantitative estimation of sulphate as an impurity in Chemical reagents. Some examples are given of the determination of the degree of purity of substances containing sulphate as impurities.     

毛细管气相色谱法测定水溶液中榄香烯哌啶盐的含量

 建立了一种准确测定水溶液中榄香烯哌啶盐含量的方法。样品水溶液经碳酸钠中和 ,并用含正十八烷(内标 )的正庚烷溶液萃取后 ,采用毛细管气相色谱法进行分析。方法的线性范围为 1 0 g/L～ 1 0 0 g/L ,精密度小于 2 % ,平均回收率为 99 96% ,RSD为 0 46% (n =5)。     

Determination of nitrate in suspended particulate matter by high-performance liquid chromatography with u.v. detection

For the determination of nitrate in suspended particulate matter (s.p.m.), high-performance liquid chromatography (h.p.l.c.) with a u.v. detector at 210 mm gives precise and accurate results. Chloride, bromate, iodide, nitrite, thiocyanate and various cations do not interfere. Calibration graphs are linear over the range 0–20 ppm of nitrat-enitrogen, and the limit of detection is 0.25 ng of nitrate-nitrogen. The coefficients of variation at 5.0- and 10.0-ppm levels are 3.4 and 2.9%, respectively. Results obtained by the h.p.l.c. method and by two 2,4-xylenol spectrophotometric methods for aqueous extracts of s.p.m. are compared. Agreement is generally good, particularly when choride is removed in the 2,4-xylenol method, but the spectrophotometric methods are much more prone to interference.     

X射线荧光光谱法测定重整铂催化剂中氯

建立重整铂催化剂中氯的X射线荧光光谱测定方法。通过研磨机将铂催化剂研磨至粒径小于75 μm的颗粒,采用仪器压片制样,通过测量不同氯含量样品的计数率,建立铂催化剂中氯含量与计数率的线性关系。氯的质量分数在0.85%~1.04%范围内与计数率成良好的线性关系,相关系数为0.9995,检出限为0.0076%。样品加标回收率为96.2%~104.2%,测定结果的相对标准偏差小于2%(n=6)。该法测定结果与电位滴定法相吻合。该方法精密度高,分析速度快,满足重整装置生产调整的要求。     

空气—乙炔焰中高氯酸镧对锶的增感效应及其分析应用

本文试验了稀土元素对空气－乙炔火焰原子吸收测定锶的影响，并且选择镧作了重点研究，发现不同镧盐对测定锶的影响各不相同，当存在每ｍＬ１５００μｇ镧（高氯酸盐）时，硝酸浓度在比较宽的范围内不影响锶的测定，本文建立建立了Ｓｒ－Ｌａ（ＣｌＯ４）３－ＨＮＯ３体系中测量锶的新方法，该方法用于人工混合稀土样品中Ｓｒ的测定，获得满意的结果。     

氢化物发生-原子荧光光谱法自动进样快速测定烟道灰中硒的应用研究

应用常规湿法消解与微波高压溶样2种不同的样品分解方法,研究了氢化物发生。原子荧光光谱法（HGAFS）测定烟道灰中的硒．硒标准系列浓度在0．000～0．024mg／L范围内与荧光强度具有良好的线性关系,相关系数为0．9998。方法检出限为0．0075mg／kg,相对标准偏差在0．87％～1．30％之间,加标回收率为98％～105％,实验证实方法具备灵敏、快速、准确等优点．亦为回收利用烟道灰中的硒提供了科学依据。     

The determination of phytoplankton pigments by high-performance liquid chromatography

A simple high-performance liquid Chromatographic method is described for the determination of chlorophylls, chlorophyll degradation products, and carotenoids in phyto-plankton cultures and marine particulate matter. Pigment extraction is carried out with acetone and methanol. After evaporation of the combined extracts under reduced pressure, the pigments are separated on a Partisil-10 stationary phase with a mobile phase consisting of light petroleum (b.p. 60–80°C), acetone, dimethyl sulphoxide and diethylamine(75: 23.25:1.5: 0.25 by volume). When chlorophyll c is present, a further development is performed with a similar, but more polar, solvent mixture. Detection is carried out spectrophotometrically at 440 nm. The method has a sensitivity for the chlorophylls of ca. 80 ng, and for carotene of ca. 5 ng. The coefficient of variation of the Chromatographic stage of the procedure lies in the range 0.6–1.8%.     

Atomic absorption spectrometric determination of copper,zinc, and lead in geological materials

An atomic absorption spectrometric method is described for the determination of copper, zinc, and lead in geological materials. The sample is digested with HF—HCl—H₂O₂; the final solution for analysis is in 10 % (v/v) HCl. Copper and zinc are determined directly by aspirating the solution into an air—acetylene flame. A separate aliquot of the solution is used for determination of lead; lead is extracted into TOPO-MIBK from the acidic solution in the presence of iodide and ascorbic acid. For a 0.50-g sample, the limits of determination are 10–2000 p.p.m. for Cu and Zn, and 5–5000 p.p.m. for Pb. As much as 40 % Fe or Ca. and 10 % Al, Mg, or Mn in the sample do not interfere. The proposed method can be applied to the determination of copper, zinc, and lead in a wide range of geological materials including iron- and manganese-rich, calcareous and carbonate samples.     

Determination of hexahydrophthalic anhydride in air using gas chromatography.

Two methods for the determination of hexahydrophthalic anhydride (HHPA) in air were developed. In a solid sorbent method, HHPA was sampled in Amberlite XAD-2 tubes, eluted in toluene and analysed by gas chromatography with flame ionization detection. The sampling rates were 0.2 and 1.0 l/min. At 15 micrograms/m3 (relative humidity less than 2%) and 27 micrograms/m3 (relative humidity 70%) no breakthrough was observed. However, at 160 micrograms/m3 (relative humidity less than 2%), 6% breakthrough was found. The sampling efficiency of the sampling rates 0.2 and 1.0 l/min did not differ. In a bubbler method, HHPA was sampled in bubblers filled with 0.1 M sodium hydroxide solution. The sodium salt of hexahydrophthalic acid was formed. No breakthrough was observed using a sampling rate of 1.0 l/min. The samples were stable during storage for eight weeks in a refrigerator. The HHP acid was esterified with methanol-boron trifluoride and analysed by gas chromatography-flame ionization detection. Apparatus for the generation of standard atmospheres of HHPA, in the range of 10-3000 micrograms/m3, was developed using the diffusion principle. For the solid sorbent method the precision (coefficient of variation) of the overall method was 2-7%, and for the bubbler method 3-19% (range 15-160 micrograms HHPA/m3; relative humidity = less than 2-70%). A comparison between the two methods was performed using the standard atmosphere. The concentrations found by the solid sorbent method were 86-98% of those found by the bubbler method (range 15-160 micrograms HHPA per m3; relative humidity = less than 2-70%). In work environment air, 93% was found using the solid sorbent method relative to the bubbler method at a mean concentration of 330 micrograms/m3 (coefficient of variation = 39%; range 200-540 micrograms/m3). For both methods, concentrations greater than 3 micrograms/m3 could be quantified at 60 min sampling with a sampling rate of 1.0 l/min.     

Tiron as a spectrophotometric reagent for the estimation of osmium

A method for the spectrophotometric determination of osmium with tiron as a reagent has been described. The reagent forms a soluble and stable coloured complex on heating with osmium in the presence of sodium acetate. The regions of maximum and minimum absorptions are at 470 mμ and 410 mμ, respectively, and the system obeys Beer's law from 2 to 32 p.p.m. of osmium. But the optimum range, with the relative analysis error of 2.878% per 1% absolute photometric error, is from 8 to 24 p.p.m. of osmium. The sensitivity of the reaction is 0.033 μg/cm² (SANDELL) and the molar extinction coefficient is 5706. In solution, the complex is formed when the osmium and the reagent are in a ratio of l : 1 ; it has an instability constant equal to approximately 5.57? 10^-5.     

Sorption–Desorption of Copper and Strontium Ions by the Soil. The Influence of Microorganisms on the State of Metals

Sorption of heavy metal (copper and strontium) ions by the meadow chernozem and grey forest soils differing in the content of organic substance was described using the Langmuir equation. The analysis of characteristic sorption coefficients demonstrated that copper possesses the enhanced affinity for the studied soil samples compared to strontium. Maximal values of the sorption of copper (0.085 mmol/g) and strontium (0.045 mmol/g) obtained for the colloidal fraction of meadow chernozem soil (particle diameter d < 1 m) are approximately 1.5 times larger than for the same fraction of grey forest soil; this ratio remains almost the same even when using the coarser fraction (d < 50 m). It was established that up to 90% of metal ions could be present in the soil in an immobile form. An increase in the concentration of heavy metal ions in the soil causes their redistribution between the components of absorbing soil complex and an increase in the fraction of metal in mobile forms (water-soluble, exchange, soluble in weakly acidic medium). Upon the microbiological treatment (bioleaching in the suspension variant) of the soils containing copper or strontium ions, the total content of metal, including its mobile forms, decreases by an order of magnitude.     

The automatic determination of fluoride in sea water and other natural waters

A Technicon AutoAnalyzer has been used for the determination of 0–1.5 μg fluoride/ml in sea water and other natural waters. Photometric measurement is made on the blue complex formed by reaction with the chelate formed between lanthanum and alizarin fluorine blue, The method has a coefficient of variation of ca. 0.9% at a fluoride level of 1.5 μm/ml.