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彭天右, Peng Tianyou and Jiang Zucheng*
Journal of Analytical Atomic Spectrometry, January 1998, Vol. 13(75-78),-0001,():
-1年11月30日
A method for the determination of trace amounts of La, Y and Eu, based on the formation of volatile chelates between rare earth elements and 1-phenyl-3-methyl-4-benzoyl-pyrazolone [5] (PMBP) in a graphite furnace, is described. PMBP was used as a chemical modifier for the volatilization of La, Y and Eu from the electrothermal vaporizer into the ICP. The factors affecting the chelating reaction between La, Y and Eu and PMBP were studied in detail, and the vaporization behavior of the chelates formed in the graphite furnace was also investigated. It was found that the presence of an excess of PMBP was necessary to prevent the thermal decomposition of the chelates during the volatilization and transportation processes. Under the optimized conditions, the limits of detection for La, Y and Eu are 8.0, 1.0 and 0.9 ng ml-1, respectively, and the relative standard deviations range from 3.3% (La) to 4.0% (Y). The linear ranges of the calibration graphs span three orders of magnitude. The method was applied to the analysis of an environmental reference material and the results obtained were in good agreement with the reference values.
Inductively coupled plasma atomic emission spectrometry, electrothermal vaporization, rare earth element-1-phenyl-3-methyl-4-benzoylpyrazolone [5] chelate, rare earth element
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彭天右, Tianyou Peng, * Xiaohai Sheng, * Bin Hu* and Zucheng Jiang*
Analyst, 2000, 125, 2089-2093,-0001,():
-1年11月30日
hermal vaporization inductively coupled plasma atomic emission spectrometry (ETV-ICP-AES) was employed for the direct determination of trace impurities in silicon carbide ceramic powders. The vaporization behaviors of silicon and five trace elements (Al, Cr, Cu, Fe and V) were studied in the presence and absence of polytetrafluoroethylene (PTFE) as fluorinating reagent. It was found that, during a 60 s ashing step at 800℃, about 97% of 100 mg of SiC can be decomposed and evaporated without considerable losses of the trace elements investigated. Calibration was performed using the standard addition method and the calibration curve method, applying spiked slurries and aqueous standard solutions, respectively. The accuracy was checked by comparison of the results with those obtained by solution fluorination assisted ETV-ICP-AES and pneumatic nebulization (PN)-ICP-AES involving wet chemical decomposition of the sample. Detection limits between 0.3μg g-1 (Al) and 0.08μg g-1 (Cu) were achieved. The precision, expressed as the relative standard deviation (RSD), was between 6.0% (for 18.2μg g-1 of Cr) and 2.8% (for 177μg g-1 of Fe).
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彭天右, Tianyou Peng a, b, *, Xun Liu a, Ke Dai a, Jiangrong Xiao a, Haibo Song a
Materials Research Bulletin 41(2006)1638-1645,-0001,():
-1年11月30日
Nanocrystalline alumina powders were prepared by combustion synthesis using glycine as fuel and nitrate as an oxidizer. The effect of the pH values in the precursor solutions on crystallite sizes, surface areas and morphologies of the synthesized alumina powder has been investigated by X-ray diffractometry, thermal analysis, nitrogen adsorption-desorption, and transmission electron microscopy. With decreasing the pH values in the precursor solutions, the obtained materials could be modified from segregated nanoparticles (pH 10.5) to aggregates of nanoparticles (pH 6.0), and finally to a flaky morphology (pH 2.5). The rates of decomposition, the interaction of coordination as well as the hydrogen bonding of the glycine and the Al-hydroxides species at different pH values were found to be responsible for the generation of flake and/or segregated nanoparticles during auto-ignition reactions. The as-prepared combustion ashes were converted into pure nanocrystalline alumina after calcination at elevated temperatures. The specific surface areas of the products calcined at 800 8C ranged from 96 to 39 m2/g with the pH decreased from 10.5 to 2.5.
A., Ceramics, A., Nanostructures, A., Oxides, B., Chemical synthesis
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彭天右, Peng Tianyou*, Du Pingwu, Hu Bin, Jiang Zucheng
Analytica Chimica Acta 421(2000)75-81,-0001,():
-1年11月30日
Fluorination assisted electrothermal vaporization (ETV) was employed as sample introduction technique for the direct determination of trace amounts of impurities in titanium dioxide solid powder by inductively coupled plasma atomic emission spectrometry (ICP-AES). A polytetrafluoroethylene (PTFE) emulsion is used as a fluorination reagent to promote the vaporization of impurity elements in TiO2 powder from the graphite tube; the vaporization behavior of matrix element (Ti) and analyte (Cr, Cu, Fe and V) were studied. Under the selected conditions, about 100mg solid sample (10ml of 1%m/v TiO2 slurry) was pipetted into furnace, a pre-volatilization of the matrix could be performed by an ashing time of 70 s at 800℃ to eliminate the matrix effect, and then the analytes were vaporized into plasma at the vaporizing temperature of 2600℃. Calibration was performed using the standard addition method. The accuracy was checked by comparison of the results with solution fluorination assisted ETV-ICP-AES and pneumatic nebulization (PN)-ICP-AES based on the wet-chemical decomposition. Limits of detection between 0.07μg g−1 (Cr) and 0.2μg g−1 (V) were achieved. © 2000 Elsevier Science B.V. All rights reserved.
Inductively coupled plasma atomic emission spectrometry, Fluorination assisted electrothermal vaporization, Slurry sampling, Titanium dioxide
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彭天右, Peng Tianyou, Jiang Zucheng* and Qin Yongchao
J. Anal. At. Spectrom., 1999, 14, 1049-1053,-0001,():
-1年11月30日
The vaporization behavior of silicon and three refractory trace elements (Al, Ti and Y) were studied in the presence and absence of a PTFE emulsion as fluorinating reagent and applying an electrothermal ICP-AES coupled system.It was found that during a 60 s ashing step at 700℃ about 90% of 100mg of Si3N4 can be decomposed and evaporated without considerable losses of the trace elements investigated. Calibration could be carried out by the standard addition method and the calibration curve method applying spiked slurries and aqueous standard solutions with peak height intensity measurements, respectively. The detection limits varied from 0.11 mg g−1 (Al) to 0.09mg g−1 (Ti) with RSD 1.9-4.2%.
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