A method based on the combination of coprecipitation with inductively coupledplasma atomic emission spectrometry (ICP-AES) was developed for the determination of impurities inhigh-purity sodium tungstate. Six elements...A method based on the combination of coprecipitation with inductively coupledplasma atomic emission spectrometry (ICP-AES) was developed for the determination of impurities inhigh-purity sodium tungstate. Six elements (Co, Cu, Fe, Mn, Ni, and Pb) were coprecipitated bylanthanum hydroxide so as to be concentrated and separated from the tungsten matrix. Effects of somefactors on the recoveries of the analytes and on the residual amount of sodium tungstate wereinvestigated, and the optimum conditions for the coprecipitation were proposed. Matrix-matchingcalibration curve method was used for the analysis. It is shown that the elements mentioned abovecan be quantitatively recovered. The detection limits for Co, Cu, Fe, Mn, Ni, and Pb are 0.07, 0.4,0.2, 0.1, 0.6, and 1.3 μg·g^(-1), respectively. The recoveries vary from 92.5% to 108%, and therelative standard deviations (RSDs) are in the range of 3.1%-5.5%.展开更多
Determination of trace rare earth elements(REEs)in 99. 999% purity yttrium oxide using the inductively coupled plasma mass spectrometric technique (ICPMS) has been developed. Instrumental parameters and factors affeci...Determination of trace rare earth elements(REEs)in 99. 999% purity yttrium oxide using the inductively coupled plasma mass spectrometric technique (ICPMS) has been developed. Instrumental parameters and factors affecitng analytical results have been studied and then optimized.Samples are analyzed directly following an acid digestion without separation or preconcentration and with limit of detection of 0. 003～0. 02 ng/ml, precision of ±5. 4%(cofficient of variation)and recovery of 90～115%. Correction for isobaric interferences from oxide ions and hydroxide ions is made mathematically. Special internal standard procedures are used to compensate drift in metal:metal oxide ratios and sensitivity. The analytical results of several samples are accurate as compared with inductively coupled plasma atomic emission spectrometry (ICPAES) and spark source mass spectrometry (SSMS).展开更多
Based on selective volatilization taking place among elements in graphite furnace, a new method for direct determination of trace titanium in high purity yttrium oxide by fluorination electrothermal vaporization(FETV)...Based on selective volatilization taking place among elements in graphite furnace, a new method for direct determination of trace titanium in high purity yttrium oxide by fluorination electrothermal vaporization(FETV)/ICP AES has been proposed. The vaporization behavior of the analyte and matrix element was studied in detail. Various factors of influence on vaporization of analyte were also investigated. Under optimal experimental conditions, the detection limit(3 σ ) of Ti is 1 0 ng/ml, and the RSD is 2 3%( n =10, c =0 2 μg/ml). The proposed method is simple, rapid and sensitive, and pretreatment is not necessary. This method can be used to directly determine trace refractory impurity titanium in high purity powder sample(Y 2O 3). The recovery for sample analysis is more than 96%.展开更多
The indirect voltammetric determination of trace sulfate (2.0×10^(-6)～4.0×10^(-5) mol/L ) with the adsorptive complex wave of lead(Ⅱ)-tetrakis (4-trimethylammonium phenyl) porphyrin (PbTTMAPP) is reported....The indirect voltammetric determination of trace sulfate (2.0×10^(-6)～4.0×10^(-5) mol/L ) with the adsorptive complex wave of lead(Ⅱ)-tetrakis (4-trimethylammonium phenyl) porphyrin (PbTTMAPP) is reported.This method has been used for the analysis of natural waters with satisfactory results.展开更多
A fluoroimmunoassay method using unlabeled europium chelate is described.The principle is similar to that of fluoroimmunoassay method using lanthanide chelate as labels.The procedure is simple because labeling process...A fluoroimmunoassay method using unlabeled europium chelate is described.The principle is similar to that of fluoroimmunoassay method using lanthanide chelate as labels.The procedure is simple because labeling process is omitted.The detection limit is about 10^(10) mol/L antigen.The relative standard deviation of immunoassay is less than 10%.The recoveries of human serum albumin and estradiol protein conjugate are 96-105% and 111% respectively.展开更多
The derivative fluorimetric characteristics of Tb—SDS and Tb—SDS—phenanthroline systems have been studied. The optimum conditions were obtained. The 2nd—derivative spectrofluorimetric method in the systems has bee...The derivative fluorimetric characteristics of Tb—SDS and Tb—SDS—phenanthroline systems have been studied. The optimum conditions were obtained. The 2nd—derivative spectrofluorimetric method in the systems has been applied to the determination of trace amounts of terbium, in rare earth ore and their oxides. The results are satisfactory.展开更多
A fluoroimmunoassay method using unlabeled Terbium chelate is described.The principle is similar to that of fluoroimmunoassay method using lanthanide chelate as labels.The procedure is simpte because labeling process ...A fluoroimmunoassay method using unlabeled Terbium chelate is described.The principle is similar to that of fluoroimmunoassay method using lanthanide chelate as labels.The procedure is simpte because labeling process is unnecessary.The recovery of HSA and albumin in urine is 107% and 95% respectively.The standard deviation is tess than 10%.展开更多
Terbium can form a ternary complex having a ratio of 1:1:1 with acetylacetone and EDTA. By adding cetyl pyridinium chloride into the above system, a marked enhancement of fluorescence intensity is observed and the ter...Terbium can form a ternary complex having a ratio of 1:1:1 with acetylacetone and EDTA. By adding cetyl pyridinium chloride into the above system, a marked enhancement of fluorescence intensity is observed and the ternary complex becomes more stable than before. For analytical application, the derivative spectrofluorimetric method has high sensitivity and the effect of foreign ions is very low. The optimum conditions were obtained. The calibration graph is linear over 5～100μg/mL.展开更多
Macroporous amino-carboxvlic chelating resin of acrylic acid series may concentrate trace rare earth in the presence of 0.1 mol/l α-hydroxy-isobutyric acid at pH 4.5.With 0.10 mol/l HCl as eluant rare earth may be el...Macroporous amino-carboxvlic chelating resin of acrylic acid series may concentrate trace rare earth in the presence of 0.1 mol/l α-hydroxy-isobutyric acid at pH 4.5.With 0.10 mol/l HCl as eluant rare earth may be eluted quantitatively and separated from Ca,Mg,Fe and Cu.This method is used to determine trace amount of rare earth in human hair,stone (in kidney and bladder),peanut,grape,strawberry,cucumber,pig liver and other biological samples.展开更多
The early literatures reported that a lot of matrix interference were encounted in the determination of lead content in various samples. Chlorides produced serious interference on analysis of lead content. All acids e...The early literatures reported that a lot of matrix interference were encounted in the determination of lead content in various samples. Chlorides produced serious interference on analysis of lead content. All acids except phosphoric acid reduced sensitivity of determination of Pb. Hinderberger et al.reported that lead was determined without the interference could be removed by using NH4H2PO4 as matrix modifier in L’vov platform atomization. The combination of pyrolytic graphite tube with solid pyrolytic graphite platform and Zeeman background correction technique was used in our experiments for determination of lead content in rice samples, with 0.1% Mg(NO)and 2% NHHPOas matrix modifier.展开更多
Vanadium is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-ammonium tetraphenylborate with microcrystalline naphthalene or by a column method in the pH range of 2.1–4.5 from a l...Vanadium is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-ammonium tetraphenylborate with microcrystalline naphthalene or by a column method in the pH range of 2.1–4.5 from a large volume of aqueous solutions of various samples. After filtration, the solid mass consisting of the vanadium complex and naphthalene was dissolved with 5 mL of dimethylformamide and the metal was determined by the third derivative spectrophotometry. Vanadium complex can alternatively be quantitatively adsorbed on ammonium tetraphenylborate-naphthalene adsorbent packed in a column and determined similarly. About 0.05 μg of vanadium can be concentrated in a column from 250 mL of aqueous sample, where its concentration is as low as 0.2 ng/mL. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the determination of trace amount of vanadium in various samples.展开更多
A proper mixture of β-cyclodextrin and sodium dodecylsulfate in aqueous solution was found to show a synergistic enhancement of the fluorescence intensity of 4,5-benzopiaselenol. The determination of trace selenium c...A proper mixture of β-cyclodextrin and sodium dodecylsulfate in aqueous solution was found to show a synergistic enhancement of the fluorescence intensity of 4,5-benzopiaselenol. The determination of trace selenium can be carried out directly in aqueous solution.展开更多
The determination of trace rhenium(Ⅶ)by differential pulse polarography in the system of H_2SO_4-(NH_2OH)_2·H_2SO_4-TeO_4^(2-) is markedly improved by the addition of Nitron,which is adsorbed on the surface of m...The determination of trace rhenium(Ⅶ)by differential pulse polarography in the system of H_2SO_4-(NH_2OH)_2·H_2SO_4-TeO_4^(2-) is markedly improved by the addition of Nitron,which is adsorbed on the surface of mercury electrode.The limit of detection is down to 2×10^(-10) M.The adsorptive peak potential is -0.80V(vs.SCE).In the ranges of 5×10^(-10)-10^(-8),1×10^(-8)-10^(-7) and 1× 10^(-7)-10^(-6)M,there are good linear relationships between the peak current increment and the concentration,of which the relative standard deviations are 9.5,6.6,1.8% respectively with the correlation coefficients of linear regression of 0.995—0.999.The results relating to this polarographic wave show that it is an adsorption-catalytic wave.The mechanism of the electrode reaction is dis- cussed.展开更多
A new highly sensitive method for determination of trace silver in waste water with 9,10- dimethylacridinium fluorosulfonate (DAFA)-K_2S_2O_3, system was suggested. In the basic aqueous so- lution, trace of silver (I)...A new highly sensitive method for determination of trace silver in waste water with 9,10- dimethylacridinium fluorosulfonate (DAFA)-K_2S_2O_3, system was suggested. In the basic aqueous so- lution, trace of silver (I) showed strongly catalytic effect on the chemiluminescence system with the pre- sence of 2,2'-bipyridine. The range of the linear relationship between light intensity and concen- tration of silver (I) is 1.0×10^(-3)mol / L to 6.0×10^(-6) mol / L. The detection limit is 8.0×10^(-9)mol / L, and the RSD for 5.0×10^(-8) mol / LAg (I) is 6.5％ (n=13). In the existence of potassium fluoride, the selectivity is higher. Combining the treatment with nitric acid, the method is applied to determine some environmental waste water and the results are similar to atomic absorption spectroscopy.展开更多
文摘A method based on the combination of coprecipitation with inductively coupledplasma atomic emission spectrometry (ICP-AES) was developed for the determination of impurities inhigh-purity sodium tungstate. Six elements (Co, Cu, Fe, Mn, Ni, and Pb) were coprecipitated bylanthanum hydroxide so as to be concentrated and separated from the tungsten matrix. Effects of somefactors on the recoveries of the analytes and on the residual amount of sodium tungstate wereinvestigated, and the optimum conditions for the coprecipitation were proposed. Matrix-matchingcalibration curve method was used for the analysis. It is shown that the elements mentioned abovecan be quantitatively recovered. The detection limits for Co, Cu, Fe, Mn, Ni, and Pb are 0.07, 0.4,0.2, 0.1, 0.6, and 1.3 μg·g^(-1), respectively. The recoveries vary from 92.5% to 108%, and therelative standard deviations (RSDs) are in the range of 3.1%-5.5%.
文摘Determination of trace rare earth elements(REEs)in 99. 999% purity yttrium oxide using the inductively coupled plasma mass spectrometric technique (ICPMS) has been developed. Instrumental parameters and factors affecitng analytical results have been studied and then optimized.Samples are analyzed directly following an acid digestion without separation or preconcentration and with limit of detection of 0. 003～0. 02 ng/ml, precision of ±5. 4%(cofficient of variation)and recovery of 90～115%. Correction for isobaric interferences from oxide ions and hydroxide ions is made mathematically. Special internal standard procedures are used to compensate drift in metal:metal oxide ratios and sensitivity. The analytical results of several samples are accurate as compared with inductively coupled plasma atomic emission spectrometry (ICPAES) and spark source mass spectrometry (SSMS).
文摘Based on selective volatilization taking place among elements in graphite furnace, a new method for direct determination of trace titanium in high purity yttrium oxide by fluorination electrothermal vaporization(FETV)/ICP AES has been proposed. The vaporization behavior of the analyte and matrix element was studied in detail. Various factors of influence on vaporization of analyte were also investigated. Under optimal experimental conditions, the detection limit(3 σ ) of Ti is 1 0 ng/ml, and the RSD is 2 3%( n =10, c =0 2 μg/ml). The proposed method is simple, rapid and sensitive, and pretreatment is not necessary. This method can be used to directly determine trace refractory impurity titanium in high purity powder sample(Y 2O 3). The recovery for sample analysis is more than 96%.
文摘The indirect voltammetric determination of trace sulfate (2.0×10^(-6)～4.0×10^(-5) mol/L ) with the adsorptive complex wave of lead(Ⅱ)-tetrakis (4-trimethylammonium phenyl) porphyrin (PbTTMAPP) is reported.This method has been used for the analysis of natural waters with satisfactory results.
基金This work was supported by National Natural Science Foundation of China.
文摘A fluoroimmunoassay method using unlabeled europium chelate is described.The principle is similar to that of fluoroimmunoassay method using lanthanide chelate as labels.The procedure is simple because labeling process is omitted.The detection limit is about 10^(10) mol/L antigen.The relative standard deviation of immunoassay is less than 10%.The recoveries of human serum albumin and estradiol protein conjugate are 96-105% and 111% respectively.
基金Project supported by the National Natural Science Foundation of China
文摘The derivative fluorimetric characteristics of Tb—SDS and Tb—SDS—phenanthroline systems have been studied. The optimum conditions were obtained. The 2nd—derivative spectrofluorimetric method in the systems has been applied to the determination of trace amounts of terbium, in rare earth ore and their oxides. The results are satisfactory.
基金supported by National Commission of Natural Science Foundation of China.
文摘A fluoroimmunoassay method using unlabeled Terbium chelate is described.The principle is similar to that of fluoroimmunoassay method using lanthanide chelate as labels.The procedure is simpte because labeling process is unnecessary.The recovery of HSA and albumin in urine is 107% and 95% respectively.The standard deviation is tess than 10%.
基金Project supported by the National Natural Science Foundation of China
文摘Terbium can form a ternary complex having a ratio of 1:1:1 with acetylacetone and EDTA. By adding cetyl pyridinium chloride into the above system, a marked enhancement of fluorescence intensity is observed and the ternary complex becomes more stable than before. For analytical application, the derivative spectrofluorimetric method has high sensitivity and the effect of foreign ions is very low. The optimum conditions were obtained. The calibration graph is linear over 5～100μg/mL.
文摘Macroporous amino-carboxvlic chelating resin of acrylic acid series may concentrate trace rare earth in the presence of 0.1 mol/l α-hydroxy-isobutyric acid at pH 4.5.With 0.10 mol/l HCl as eluant rare earth may be eluted quantitatively and separated from Ca,Mg,Fe and Cu.This method is used to determine trace amount of rare earth in human hair,stone (in kidney and bladder),peanut,grape,strawberry,cucumber,pig liver and other biological samples.
文摘The early literatures reported that a lot of matrix interference were encounted in the determination of lead content in various samples. Chlorides produced serious interference on analysis of lead content. All acids except phosphoric acid reduced sensitivity of determination of Pb. Hinderberger et al.reported that lead was determined without the interference could be removed by using NH4H2PO4 as matrix modifier in L’vov platform atomization. The combination of pyrolytic graphite tube with solid pyrolytic graphite platform and Zeeman background correction technique was used in our experiments for determination of lead content in rice samples, with 0.1% Mg(NO)and 2% NHHPOas matrix modifier.
基金theNationalResearchCouncilofIslamicRepublicofIran (No .NRCI1719)
文摘Vanadium is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-ammonium tetraphenylborate with microcrystalline naphthalene or by a column method in the pH range of 2.1–4.5 from a large volume of aqueous solutions of various samples. After filtration, the solid mass consisting of the vanadium complex and naphthalene was dissolved with 5 mL of dimethylformamide and the metal was determined by the third derivative spectrophotometry. Vanadium complex can alternatively be quantitatively adsorbed on ammonium tetraphenylborate-naphthalene adsorbent packed in a column and determined similarly. About 0.05 μg of vanadium can be concentrated in a column from 250 mL of aqueous sample, where its concentration is as low as 0.2 ng/mL. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the determination of trace amount of vanadium in various samples.
基金Project supported by the National Natural Science Foundation of China.
文摘A proper mixture of β-cyclodextrin and sodium dodecylsulfate in aqueous solution was found to show a synergistic enhancement of the fluorescence intensity of 4,5-benzopiaselenol. The determination of trace selenium can be carried out directly in aqueous solution.
文摘The determination of trace rhenium(Ⅶ)by differential pulse polarography in the system of H_2SO_4-(NH_2OH)_2·H_2SO_4-TeO_4^(2-) is markedly improved by the addition of Nitron,which is adsorbed on the surface of mercury electrode.The limit of detection is down to 2×10^(-10) M.The adsorptive peak potential is -0.80V(vs.SCE).In the ranges of 5×10^(-10)-10^(-8),1×10^(-8)-10^(-7) and 1× 10^(-7)-10^(-6)M,there are good linear relationships between the peak current increment and the concentration,of which the relative standard deviations are 9.5,6.6,1.8% respectively with the correlation coefficients of linear regression of 0.995—0.999.The results relating to this polarographic wave show that it is an adsorption-catalytic wave.The mechanism of the electrode reaction is dis- cussed.
文摘A new highly sensitive method for determination of trace silver in waste water with 9,10- dimethylacridinium fluorosulfonate (DAFA)-K_2S_2O_3, system was suggested. In the basic aqueous so- lution, trace of silver (I) showed strongly catalytic effect on the chemiluminescence system with the pre- sence of 2,2'-bipyridine. The range of the linear relationship between light intensity and concen- tration of silver (I) is 1.0×10^(-3)mol / L to 6.0×10^(-6) mol / L. The detection limit is 8.0×10^(-9)mol / L, and the RSD for 5.0×10^(-8) mol / LAg (I) is 6.5％ (n=13). In the existence of potassium fluoride, the selectivity is higher. Combining the treatment with nitric acid, the method is applied to determine some environmental waste water and the results are similar to atomic absorption spectroscopy.
