汽油含铅量测定方法的研究——石墨炉原子吸收法

国家标准ＧＢ Ｔ 80 2 0 - 87《汽油铅含量测定 (原子吸收光谱法 )》 ,是将汽油试样用甲基异丁基甲酮稀释 ,加入磺和季铵盐与烷基铅化合物反应使之稳定。以氯化铅为标样 ,用火焰原子吸收光谱法测定试样中铅含量。采用上述处理方法 ,虽然稳定性高 ,重现性好 ,但灵敏度低 ,成本高 ,毒性大 ,会造成环境污染 ,还特别繁琐。本方法改善了以上方法的弊端。一、测定方法1 方法概要石墨炉原子吸收法测定铅含量是较灵敏的方法 ,可直接定性样品为有无铅汽油。有铅汽油 ,是以氯化铅为标样 ,用石墨炉原子吸收光谱法 ,在波长 2 83 3纳米处 ,测定试样中铅含…     

石墨炉原子吸收光谱法测定蔬菜中铅和镉

目的:分析探讨蔬菜中铅、镉测定的最佳工作条件。方法:对西兰花与蒜苔蔬菜样品采用硝酸-高氯酸-硫酸消解,利用石墨炉原子吸收光谱法对蔬菜中的铅与镉进行测定。结果:在最佳条件下利用石墨炉原子吸收光谱法测定蔬菜中铅和镉,测得加标回收率铅98.90%,镉102.6%。结论:在对蔬菜中的铅和镉含量进行检测中,采用石墨炉原子吸收光谱法具有快捷、准确的优势,可得到满意的测定结果,满足分析要求。     

氢化物发生-原子吸收光谱法测定金银花中的痕量铅

目的:研究了氢化物发生-原子吸收光谱法测定金银花中的铅的反应体系;方法:使用氢化物发生-原子吸收光谱法;结果:相对标准偏差小于(RSD,n=7)小于1.723%,回收率为95.38%~108.67%,检出限为6.1×10-10;结论:方法具有快速、准确、灵敏度高、经济实用等优点,用于金银花中铅的测定,结果令人满意。     

浅谈原子吸收光谱法测钢铁中锰含量的校准曲线绘制方法

火焰原子吸收光谱法测定钢材中锰含量已成为一种广泛应用于检验检测领域的快速分析方法,在检测过程中,校准曲线的绘制至关重要。本文介绍了火焰原子吸收光谱法测定钢材中锰含量的两种校准曲线的绘制方法,并进行了对比。     

悬浮液进样-火焰原子吸收光谱法测定饲料中的微量元素

本文介绍了一种以邻苯二甲酸二丁酯-琼脂溶液为悬浮液,直接进样火焰原子吸收光谱法测定饲料中的微量元素铁、锌、铜、锰的方法。讨论了悬浮液制备、样品粒径、取样量等因素对测定结果的影响。经优化后,该方法各元素的加标回收率在95.7%～105.6%内,精密度RSD小于10%。与干法、湿法消解相比:该法简单快速、效率高、测定结果准确可靠。     

石墨炉原子吸收光谱法测定六堡茶中的铅和镉

本文用石墨炉原子吸收光谱法测定六堡茶中的铅和镉含量,优化了样品前处理条件和光谱仪的各项技术参数。结果表明:应用微波消解-石墨炉原子吸收法测定六堡茶样品中的铅和镉时,铅的加标回收率在93.1%~99.2%之间,镉的加标回收率在92.3~97.3%之间,相对标准偏差均小于5%。方法准确、方便,可满足检测六堡茶中的铅和镉要求。     

原子吸收光谱法测定海洋动物石蚴中的微量元素含量

本文采用火焰原子吸收光谱法测定了石蜐中的锌、铜、铁、锰四种微量元素和镁、钙两种常量元素的含量,精密度为0.26～5.54％,回收率为94.9～104.5％,同时用原子发射法测定了钾元素的含量。     

用石墨炉原子吸收光谱法测定次磷酸钠中微量铅

试样直接用水溶解,以磷酸氢二铵作测铅基体改进剂,考察了基体改进剂用量,原子化温度以及基体元素对测定的影响,在最佳测定条件下,用石墨炉原子吸收光谱法测定了次磷酸钠中微量铅,测试结果为:线性范围为0～60×10-3μg/mL,检出限为1.6×10-3μg/mL,回收率为94.0%～102.6%,RSD<5%。方法简便,灵敏度高,重现性较好。     

石墨炉原子吸收光谱法测定大米中镉含量研究

目的:通过采用石墨炉原子吸收光谱法来对大米中镉的含量进行测量。方法:首先对所要进行试验的大米做实验前的处理,对大米采用湿法消解法进行处理,采用石墨原子吸收光谱法来测定大米中镉的含量,从而对大米中镉含量的最佳测定时间、重复性、回收率和精密度进行检测。结果:选用实验大米质量1g,采用消解剂为硝酸,实验时间13h,在该实验条件进行处理,然后对进行酸化处理的大米采用石墨炉原子吸收光谱法对镉含量进行测定。石墨炉原子吸收光谱法测定大米中镉含量的加标回收率为98.78%。结论:通过石墨炉原子吸收光谱法对大米中镉含量进行测量,具有测量准确、重复性好、误差小的特点,可以用于大米中镉含量的测定。     

微波消化石墨炉原子吸收光谱法测定中成药中痕量铅、镉方法研究

本文建立了微波消化石墨炉原子吸收光谱法测定中成药中铅、镉方法。方法的相对标准偏差对铅为5.1％,镉为7.0％。回收率铅在94—110％之间,镉在99—112％之间,检出限分别为铅0.6ng/mL、镉0.02ng/mL。     

Solid phase extraction method for the determination of lead, nickel, copper and manganese by flame atomic absorption spectrometry using sodium bispiperdine-1,1'-carbotetrathioate (Na-BPCTT) in water samples

A novel column solid phase extraction procedure was developed for the determination of lead, nickel, copper and manganese in various water samples by flame atomic absorption spectrometry (FAAS) after preconcentration on sodium bispiperdine-1,1'-carbotetrathioate (Na-BPCTT) supported by Amberlite XAD-7. The sorbed element was subsequently eluted with 1M nitric acid and the acid eluates are analysed by Flame atomic absorption spectrometry (FAAS). Various parameters such as pH, amount of adsorbent, eluent type and volume, flow-rate of the sample solution, volume of the sample solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH for the sorption of above mentioned metal ions was about 6.0+/-0.2. The loading capacity of adsorbent for Pb, Cu, Ni and Mn were found to 28, 26, 22 and 20x10(-6) g/mL, respectively. The recoveries of lead, copper, nickel and manganese under optimum conditions were found to be 96.7-99.2 at the 95% confident level. The limit of detection was 3.0, 3.2, 2.8 and 3.6x10(-6) g/mL for lead, copper, nickel and manganese, respectively by applying a preconcentration factor 50. The proposed enrichment method was applied for metal ions in various water samples. The results were obtained are good agreement with reported method.     

原子吸收光谱法测定水中铅的不确定度分析

目的:为提高检测结果精确度,评定水中铅的不确定度。方法:分析水中铅不确定度的来源,通过计算得出该法测定水中铅的扩展不确定度。结果:测量结果表明扩展不确定度U95=2.3μg/L,适用于每个水样的检测结果。结论:该方法简便,适合于每一个样本的检测结果,可参考用于水中某些检测参数的不确定评定。     

A novel slurry sampling analysis of lead in different water samples by electrothermal atomic absorption spectrometry after coprecipitated with cobalt/pyrrolidine dithiocarbamate complex

A preconcentration/separation technique based on the coprecipitation of lead with cobalt/pyrrolidine dithiocarbamate complex (Co(PDC)(2)) and subsequently its direct slurry sampling determination by electrothermal atomic absorption spectrometry (AAS) was described. For this purpose, at first, lead was coprecipitated with cobalt/pyrrolidine dithiocarbamate complex formed using ammonium pyrrolidine dithiocarbamate (APDC) as a chelating agent and cobalt as a carrier element. The supernatant was then separated and the slurry of the precipitate prepared in Triton X-100 was directly analyzed by electrothermal atomic absorption spectrometry with respect to lead concentration. The effects of experimental conditions on coprecipitation of lead with gathering precipitate as well as homogeneity and stability of the slurry were investigated. After the optimization of experimental parameters, a 100-fold enrichment of the analyte with quantitative recovery (>90%) and high precision (<10% R.S.D.) were obtained. By using the proposed technique, the lead concentrations in heavy matrices of Certified Sea-water and wastewater samples could be practically and rapidly determined in the range of 95% confidence level. The detection limit of the described method for lead using sample-matching blanks was 1.5ng/L (3sigma, N=10).     

Monochromatization of resonance radiation in Zeeman atomic absorption spectrometry

Two methods of background correction in atomic absorption spectrometry with nonselective atomic effects are investigated: first, with a source possessing a continuous spectrum and, second, that of correction based on the Zeeman effect. The parameters of the monochromator, which was developed expressly for Zeeman atomic absorption spectrometry, are considered. __________ Translated from Izmeritel’naya Tekhnika, No. 9, pp. 20–24, September, 2007.     

Determination of mercury in water and fish samples by cold vapor atomic absorption spectrometry after solid phase extraction on agar modified with 2-mercaptobenzimidazole

Due to the consumption of chicken and chicken products in Turkey at high ratio, trace metal content of chicken and chicken products from Turkey were determined by atomic absorption spectrometry after microwave digestion. The accuracy of the method was confirmed by analysis of standard reference material (NIST SRM 1577b Bovine liver). Trace element content in various parts of chicken samples and chicken products were to be in the range of 0.10-114 microg/g for copper, 0.25-6.09 microg/kg for cadmium, 0.01-0.40 microg/g for lead, 0.10-0.91 microg/g for selenium, 0.05-3.91 microg/g for manganese, 0.06-0.10 microg/g for arsenic, 0.01-0.72 microg/g for chromium, 0.01-2.08 microg/g for nickel, 0.01-0.02 microg/g for cobalt, 0.10-1.90 microg/g for aluminium, 1.21-24.3 microg/g for zinc, 2.91-155 microg/g for iron. The levels of lead in some analyzed chicken products were higher than the recommended legal limits for human consumption.     

Detection and determination of manganese concentration in water using a fiber Bragg grating coupled with nanotechnology

Through this paper we experimentally demonstrate the fabrication of a fiber Bragg grating (FBG) chemical sensor to detect and determine the manganese concentration in water and compare our results with sophisticated spectroscopic methods, such as atomic absorption spectrometry and the inductively coupled plasma method. Here we propose a simple method to develop a thin layer of gold nanoparticles above the etched grating region to enhance the sensitivity of the reflected spectrum of the FBG. By doing so, we achieve a sensitivity of 1.26 nm/parts per million in determining the trace level of Mn in water. Proper reagents are used to detect manganese in water.     

Am Animal Model for Investigating Manganese Absorption at Various Regions of the Gastrointestinal Tract

Abstract

The absorption of manganese chloride at variou sites of the gastrointestinal (GI) tract was studied in rats. Manganese chloride was administered by direct injection into either the stomach (intragastric, i.g.), the duodenum (intraduodenal injection, i.d.), or by simple oral administration (p.o). Serum Mn²⁺ concentrations in the hepatic portal vein were measure using a newly developed atomic absorption method. Administrations of manganese chloride by p.o., i.g. and i.d. routes increased endogenous serum Mn²⁺ concentratio by approximately 100%. However, the absorption kinetics of the three routes of administration were different. These results indicated that manganese chloride was readily absorbed after i.d. and i.g. administrations. The absorption of manganese chloride after p.o. administration was delayed, possibly due to passage through the esophagus and stomach into the intestine prior to intestinal absorption. The method was also applied to screening GI absorption of a number of manganese chelate compounds. The less polar compounds were not preferentially absorbed compared with manganese chloride, which is more ionic in nature.     

Am Animal Model for Investigating Manganese Absorption at Various Regions of the Gastrointestinal Tract

The absorption of manganese chloride at variou sites of the gastrointestinal (GI) tract was studied in rats. Manganese chloride was administered by direct injection into either the stomach (intragastric, i.g.), the duodenum (intraduodenal injection, i.d.), or by simple oral administration (p.o). Serum Mn²⁺ concentrations in the hepatic portal vein were measure using a newly developed atomic absorption method. Administrations of manganese chloride by p.o., i.g. and i.d. routes increased endogenous serum Mn²⁺ concentratio by approximately 100%. However, the absorption kinetics of the three routes of administration were different. These results indicated that manganese chloride was readily absorbed after i.d. and i.g. administrations. The absorption of manganese chloride after p.o. administration was delayed, possibly due to passage through the esophagus and stomach into the intestine prior to intestinal absorption. The method was also applied to screening GI absorption of a number of manganese chelate compounds. The less polar compounds were not preferentially absorbed compared with manganese chloride, which is more ionic in nature.