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Objective@#To establish the method for determination of iron and its inorganic oxide in the air of workplace.@*Methods@#The iron and its inorganic oxide was collected by MCE filter membrane and then digested by electric heating digestion apparatus. Atomic absorption spectrophotometer (AAS) or inductively coupled plasma optical emission spectrometry (ICP-OES) was used for the detection of iron and its inorganic oxide.@*Results@#The sampling efficiency was higher than 97%; under the 372.0 nm wavelength, the linearity of AAS was good at the range of 1.0~150.0 μg/ml, the minimum quantitation concentration was 0.28 mg/m3, the maximum quantitation concentration was 6.24 mg/m3, the recovery was ranged from 99%~102%, the RSD of intra-and inter-batch precision were 0.5%~1.2% and 1.0%~2.2%, respectively; the linearity of ICP-OES was good at the range of 0.1~500 μg/ml, the minimum quantitation concentration was 0.28 mg/m3, the maximum quantitation concentration was 20.8 mg/m3, the recovery was ranged from 101%~103%, the RSD of intra-and inter-batch precision were 0.5%~1.0% and 1.5%~1.6%, respectively.@*Conclusion@#The sampling method and determination method meet the requirements of analysis and apply to the collection and determination of iron and its inorganic oxide in the air of workplace.
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Objective To establish a rapid determination method for the exchangeable and reducible manganese.Methods In NH4Ac solution,manganese was determined by flame atomic absorption spectrophotometry.Results The linear ranges was 0.40-2.00 ?g/ml for exchangeable manganese and 100-5.00 ?g/ml for reducible manganese respectively.The detection limits were 0.012 ?g/ml for exchangeable manganese and 0.0078 ?g/ml for reducible manganese respectively.The RSDs were lower than 1.2%.The recovery rates were 100.2% for exchangeable manganese and 98.8% for reducible manganese respectively.The correlative coefficients were 0.9992 for exchangeable manganese and 0.9995 for reducible manganese respectively.Conclusion This method is rapid,simple,sensitive and accurate.
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Objective In order to find the pollution source and provide some useful references for the controlling of the heavy metal pollution to the tea. Methods From March to April,2007,the soil and tea samples were collected from 10 tea gardens in the main producing areas. The soil samples were digested. The tea samples were dissolved by mix acid solution after being burnt into ashes,then the contents of lead and copper were determined by FAAS. Results There was a significant positive correlation between tea and soil in the lead contents (r lead=0.650 2,P
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0.05). Conclusion The present method has many advantages such as simplicity of operation,rapidity,better accuracy for the accurate quantitative analysis of urinary manganese.
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Objective To develop a simple test method to determine lead in the food by atomic absorption spectrometry. Methods Based on the system of HCl-K3Fe(CN)6-KBH4, lead in the food samples was oxidized into Pb4+ and formed PbH4 in the continuous flow injection hydride generator and then the PbH4 vapour was put into atomization, the atomic absorption spectrometry was used to determine lead. Results The detection limit was 0.070 ?g /L, the linear range of standard curve was 0-16 ?g /L, the correlation coefficient (r) was 0.999 5, RSD was less than 1.92% for the standard solution, and less than 3% for food samples, average recovery rate was 97%. Conclusion This method is simple, low cost and applicable to the determination of trace lead in the food.
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Objective To select a matrix modifier,which can effectively eliminate the matrix interference in the determination of chromium in cosmetics by graphite furnace atomic absorption spectrometry(GFAAS).Methods The orthogonal experiment design was used to define the best operation parameter of graphite furnace.Vitamin C,(NH4)H2PO4,(NH4)2HPO4,NH4Cl and Mg(NO3)2 were added respectively as the matrix modifiers.The effect of five matrix modifiers was compared by precision test.Results When(NH4)H2PO4 was taken as the chemical modifier,the determination result was satisfied.The characteristic mass was 5.68?10-12 g,relative standard deviation were from 2.11% to 4.46%.The rate of recovery of two cosmetics samples were 95.2% and 102.01%.Conclusion(NH4)H2PO4 can increase the ashing temperature,decrease the atomization temperature,eliminate the matrix interference and the result has good precision and accuracy.
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Objective To develop a method for the determination of cobalt in urine by graphite furnace atomic absorption spectrometry(GFAAS).Methods Usingthe matrixmodifier tofind the best condition byimprovingthe cineration temperature and reducing the interference of gas phase in atomization stage.Results The best cineration temperature and atomization temperature was 1 200 ℃and 2 450 ℃respectively,taking15% PdCl2,NH3H2PO4 and HNO3 as the matrix modifier.The background absorb value was less than 0.05.The linear range was 0～75 ?g/L,the correlation coefficient was over 0.999,the average recovery rate was 97.2%,the relative standard deviations were 3.5%～6.5%,the detection limit was 1.5 ?g/L.The result of 16 urine samples determined with the present method showed no significant difference compared with that by using polarography.Conclusion This method is sensitive,accurate,simple and is applicable tothe determination ofcobalt in urine.
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0.999 0), the detection limit was 3.0 ng/L, the recovery rates were 97%-100%, the relative standard deviation (RSD) was less than 1.9%. Conclusion This method is characterized by convenient procedure, good sensitivity and satisfactory accuracy and is applicable to determination of antimony in the urine.
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Objective To develop a pretreatment method with the microwave digestion for the determination of soil total chromium. Methods The nitric acid and hydrofluoric acid were added into the samples, the microwave digestion under the certain condition was conducted and then the sulfuric acid was added on the controllable electric stove. Flame atom absorption spectrophotometry or diphenylcarbohydrazide spectrophotometry was used to determine soil total chromium according to the condition. Results RSDs were from 1.20% to 11.08%. The Environmental Soil Standard test demonstrated that the results were in the guarantee value, as for ESS-1, RSD=2.57%, as for ESS-3, RSD=2.20%. Conclusion The microwave digestion is considered as a good pretreatment method for the determination of soil total chromium with the advantages of safe, rapid and accurate.
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Objective To establish the methods for direct determination of manganese in the urine by flame atom absorption spectrophotometry (AAS). Methods Manganese in the urinary samples were determined directly and the result was compared with that by acid digestion. Results The results showed a good linearity, from 0.01 to 0.80 ?g/ml, r=0.9997, y=0.001 87+0.785 3 x. For the same urinary sample, the average urinary manganese content was 0.027 ?g/ml, standard deviation was 0.000 015 ?g/ml, RSD=0.056%. The average recovery rate was 95.1%. No significant difference was seen compared with the acid digestion. Conclusion The direct determination of urinary manganese by AAS is simple, rapid, accurate and feasible.
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Objective To develop a method to determine trace Pb and Cd in mineral water, tap water and sea water. Methods Pb and Cd in the samples were enriched in the sulphydryl cotton column under the conditions that the pH of the samples was adjusted to 7 and collected by washing the column with 4 ml of 0.2 mol/L HCl solution. The concentration of Pb and Cd was determined by flame atomic absorption spectrophotometry. Results Pb and Cd were not detected in four kinds of mineral water samples, but in tap water and sea water, Pb was 1.56 ?g/L and 0.43 ?g/L, Cd was 0.62 ?g/L and 0.07 ?g/L respectively. The rates of recovery were 96.6%-104.0% and RSD was
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Objective To establish a method for the determination of Fe, Cu, Zn, Mn in the pollen by flame atomic absorption spectrometry(FAAS).Methods Wet digestion-flame atomic absorption spectrophotometry was used to determine the content of Fe, Cu, Zn, Mn in the pollen.Results In the selected experimental conditions, the recovery rates of these elements were 98.5%-103.0% and the coefficient of variation was 1.13%-2.36%.The detection limits were 0.40 ?g/L for Fe, 0.08 ?g/L for Cu, 0.20 ?g/L for Zn, 0.14 ?g/L for Mn.The linear range was 0.00-2.00 mg/L.Conclusion FAAS is simple, fast, accurate for the determination of Fe, Cu, Zn, Mn in the pollen.
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Objective To establish a method for determination of copper, manganese and cadmium in human urine by transversely heated GFAAS.Methods Matrix modifiers were used and background absorption was deducted, copper, manganese and cadmium in human urine were determined by transversely heated GFAAS after digestion.Results 5 g/L Mg(NO3)2 was taken as the matrix modifier when copper and manganese were determined and 0.3 g/L Mg(NO3)2 and 5 g/L NH4H2PO4 was taken as the matrix modifier when cadmium was determined.Under the designed standard conditions, the detection limits of copper, manganese and cadmium were 0.028-0.060 ?g/L;RSDs were 1.1%-5.1%;Recovery rates were 94.2%-107.5%.Conclusion The method is simple, accurate and sensitive, and is applicable to the determination of copper, manganese and cadmium in human urine.