A method for the analysis of selenium in marine aquatic products by HG-AFS has been investigated. The method is based on the reduction of inorganic selenium to volatile SeH2 which is bubbled out by carrier gas of pure...A method for the analysis of selenium in marine aquatic products by HG-AFS has been investigated. The method is based on the reduction of inorganic selenium to volatile SeH2 which is bubbled out by carrier gas of pure argon, and then swept to Ar-H2 flame quarts atomizer to measure its fluorescence intensity. The hydride generation, transportation, atomization and some instrumental parameters were studied by a kind of orthogonal design. The optimum conditions selected are as follows： reactive acidity, 20% HC1; the amount of NaBH4, 4.9mL; gas flow of argon, 600mLmin^-1; atomizing temperature, 200 ℃ ; negative high voltage, - 300V; light current, 100 mA; integral time, 7s. The detection limit of the presented method is 0.072μgL^-1 for selenium. The calibration curve shows a satisfactory line inthe concentration range from 0.000 to 1.000μgL^-1 Se. The recovery is 95.8%-102.2%.展开更多
0.2000g mogroside sample is digested by 7.0ml nitric acid and 3.0ml hydrogen peroxide, and generated by coprecipitation enrichment hydride - atomic fluorescence spectrometry determines trace selenium in it. Under opti...0.2000g mogroside sample is digested by 7.0ml nitric acid and 3.0ml hydrogen peroxide, and generated by coprecipitation enrichment hydride - atomic fluorescence spectrometry determines trace selenium in it. Under optimum experiment conditions, a standard curve was produced using selenium standard solution, the linear equation is Ise=2890.6c＋0.0012,compared wish the linear relaticnship is not by coprecipitation direct determination of standard series Ise=82.56c＋0.0018 Selenium detection sensitivity was increased by 35.01 times,the correlation coefficient of obtained linear regression equation is 0.9996, the detection limit is 0.0012~tg/L and the relative standard deviation is 0.76% （n=5）. Containing 0.1808pg.g-1 Se Luo Han Shen samples. Based on mogroside sample, add a certain of standard solution to do recovery experiment, the obtained recovery rate is in 95.8%-103.6% and the result is satisfactory.展开更多
A method for the analysis of trace germanium in marine sediments by HG-AFS has been investigated. The experimental conditions such as the acidity of reduction reaction, the amount of sodium boro-hydride, the carrier g...A method for the analysis of trace germanium in marine sediments by HG-AFS has been investigated. The experimental conditions such as the acidity of reduction reaction, the amount of sodium boro-hydride, the carrier gas flow rate, etc., were tested and optimized by using a kind of orthogonal design. The detection limit of the presented method is 0.95 μg L -1 for germanium. The calibration curve shows a satisfactory line in the concentration range 0-320 μg L -1 Ge with a variation coefficient of ±2.1%.展开更多
Standard reference material and different geological samples were dissolved by system A (the mixture of nitric and perchloric acids) and system B (mixture of nitric, perchloric and hydrofluoric acids), and total Se in...Standard reference material and different geological samples were dissolved by system A (the mixture of nitric and perchloric acids) and system B (mixture of nitric, perchloric and hydrofluoric acids), and total Se in all samples was measured by hydride-generation atomic fluorescence spectrometry (HG-AFS) after concentration with thiol cotton fiber (TCF). The analytical results obtained by the two digestion method are in good agreement (within the limit of errors) for most of the samples, particularly for those having recommended values. The Se concentrations determined by the two methods are of no difference, and the correlation coefficient is 0.9986; the relative standard deviation (RSD) for the determination of 0.04 μg/g Se is 10.2%. The recovery rates of systems A and B by the stan- dard-addition method were 96%–106% and 99%–104%, respectively.展开更多
Flue gas from coal combustion contains significant amounts of volatile selenium （Se）. The capture of Se in the flue gas desulfurization （FGD） scrubber unit has resulted in a generation of metal-laden residues. It ...Flue gas from coal combustion contains significant amounts of volatile selenium （Se）. The capture of Se in the flue gas desulfurization （FGD） scrubber unit has resulted in a generation of metal-laden residues. It is important to determine Se speciation to understand the environmental impact of its disposal. A simple method has been developed for selective inorganic Se（IV）, Se（VI） and organic Se determination in the liquid-phase FGD residues by hydride generation atomic fluorescence spectrometry （AFS）. It has been determined that Se（IV）, Se（VI） and organic Se can be accurately determined with detection limits （DL） of 0.05, 0.06 and 0.06 μg/L, respectively. The accuracy of the proposed method was evaluated by analyzing the certified reference material, NIST CRM 1632c, and also by analyzing spiked tap-water samples. Analysis indicates that the concentration of Se is high in FGD liquid residues and primarily exists in a reduced state as selenite （Se（IV））. The toxicity of Se（IV） is the strongest of all Se species. Flue gas desulfurization residues pose a serious environmental risk.展开更多
文摘A method for the analysis of selenium in marine aquatic products by HG-AFS has been investigated. The method is based on the reduction of inorganic selenium to volatile SeH2 which is bubbled out by carrier gas of pure argon, and then swept to Ar-H2 flame quarts atomizer to measure its fluorescence intensity. The hydride generation, transportation, atomization and some instrumental parameters were studied by a kind of orthogonal design. The optimum conditions selected are as follows： reactive acidity, 20% HC1; the amount of NaBH4, 4.9mL; gas flow of argon, 600mLmin^-1; atomizing temperature, 200 ℃ ; negative high voltage, - 300V; light current, 100 mA; integral time, 7s. The detection limit of the presented method is 0.072μgL^-1 for selenium. The calibration curve shows a satisfactory line inthe concentration range from 0.000 to 1.000μgL^-1 Se. The recovery is 95.8%-102.2%.
文摘0.2000g mogroside sample is digested by 7.0ml nitric acid and 3.0ml hydrogen peroxide, and generated by coprecipitation enrichment hydride - atomic fluorescence spectrometry determines trace selenium in it. Under optimum experiment conditions, a standard curve was produced using selenium standard solution, the linear equation is Ise=2890.6c＋0.0012,compared wish the linear relaticnship is not by coprecipitation direct determination of standard series Ise=82.56c＋0.0018 Selenium detection sensitivity was increased by 35.01 times,the correlation coefficient of obtained linear regression equation is 0.9996, the detection limit is 0.0012~tg/L and the relative standard deviation is 0.76% （n=5）. Containing 0.1808pg.g-1 Se Luo Han Shen samples. Based on mogroside sample, add a certain of standard solution to do recovery experiment, the obtained recovery rate is in 95.8%-103.6% and the result is satisfactory.
基金supported by the Key Science and Technology pnasp Minsty of Educaton umder contr act(N0.200010-0079).
文摘A method for the analysis of trace germanium in marine sediments by HG-AFS has been investigated. The experimental conditions such as the acidity of reduction reaction, the amount of sodium boro-hydride, the carrier gas flow rate, etc., were tested and optimized by using a kind of orthogonal design. The detection limit of the presented method is 0.95 μg L -1 for germanium. The calibration curve shows a satisfactory line in the concentration range 0-320 μg L -1 Ge with a variation coefficient of ±2.1%.
基金the Knowledge-Innovation Program of the Chinese Academy of Sciences（KZCX3-SW-125）；the National Natural Science Foundation of China（Grant Nos.60633110,40003008）.
文摘Standard reference material and different geological samples were dissolved by system A (the mixture of nitric and perchloric acids) and system B (mixture of nitric, perchloric and hydrofluoric acids), and total Se in all samples was measured by hydride-generation atomic fluorescence spectrometry (HG-AFS) after concentration with thiol cotton fiber (TCF). The analytical results obtained by the two digestion method are in good agreement (within the limit of errors) for most of the samples, particularly for those having recommended values. The Se concentrations determined by the two methods are of no difference, and the correlation coefficient is 0.9986; the relative standard deviation (RSD) for the determination of 0.04 μg/g Se is 10.2%. The recovery rates of systems A and B by the stan- dard-addition method were 96%–106% and 99%–104%, respectively.
基金supported by the National Natural Science Foundation of China (No.90410018)the Shanxi Nature Science Foundation (No.20051017)+1 种基金the Shanxi Returned Scholar Research Project (No.2005-21)the Programfor Changjiang Scholars and Innovative Research Team at University in MOE,China (No.IRT0517)
文摘Flue gas from coal combustion contains significant amounts of volatile selenium （Se）. The capture of Se in the flue gas desulfurization （FGD） scrubber unit has resulted in a generation of metal-laden residues. It is important to determine Se speciation to understand the environmental impact of its disposal. A simple method has been developed for selective inorganic Se（IV）, Se（VI） and organic Se determination in the liquid-phase FGD residues by hydride generation atomic fluorescence spectrometry （AFS）. It has been determined that Se（IV）, Se（VI） and organic Se can be accurately determined with detection limits （DL） of 0.05, 0.06 and 0.06 μg/L, respectively. The accuracy of the proposed method was evaluated by analyzing the certified reference material, NIST CRM 1632c, and also by analyzing spiked tap-water samples. Analysis indicates that the concentration of Se is high in FGD liquid residues and primarily exists in a reduced state as selenite （Se（IV））. The toxicity of Se（IV） is the strongest of all Se species. Flue gas desulfurization residues pose a serious environmental risk.
