University of North Florida
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Contact Info

Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Xue Feng Yin

Abbrev:
Yin, X.F.
Other Names:
Xuefeng Yin
Address:
Department of Chemistry, Zhejiang University, Hangzhou 310027, China
Phone:
+86-571-795-2070
Fax:
+86-571-795-1895

Citations 7

"Determination Of Nickel After Online Sorbent Preconcentration By FI-FAAS Using Dimethylglyoxime As A Complexing Agent"
Microchem. J. 1999 Volume 63, Issue 3 Pages 365-373
Akbar Ali, Yingxue Ye, Guangming Xu, Xuefeng Yin and Tao Zhang

Abstract: Dimethylglyoxime (DMG) has been tested as a complexing agent for the determination of nickel after online pre-concentration on RP-C-18 in a microcolumn using flow injection coupled with a flame atomic absorption spectrometry system (FI-FAAS). The Ni-DMG complexes formed online can be adsorbed on the C-18 sorbent. Various parameters affecting the online Ni-DMG complex formation and its subsequent adsorption in the microcolumn as well as its elution into the nebulizer of the FAAS were optimized. A 10^-3 mol/L solution of DMG in 4% ethanol was mixed online with an aqueous sample solution acidified to 0.1% (v/v) nitric acid and Rowed for 30 a through the microcolumn. The adsorbed Ni-DMG complex in the microcolumn was eluted with ethanol containing 1% HNO3 into the nebulizer of the FAAS in 10 s. A good precision (RSD = 1.7%, n = 14), high enrichment factor (2I), and high sample throughput (90 h-1) with detection limit (3s) 3 µg/L were obtained. The method was applied to standard reference materials, i.e., NBS-362, NBS-364 (special low-alloy steel), and mussel (GBW 08571), for the determination of nickel and the results were in good agreement with certified values. Nickel recovery from seawater and high-purity magnesium oxide in the range 98-100% can be obtained by this method,

"Copper Determination By Flow Injection On-line Sorbent Preconcentration Coupled With Flame Atomic Absorption Spectrometry Using 1,10 Phenanthroline"
Lab. Rob. Autom. 2000 Volume 12, Issue 2 Pages 97-103
Akbar Ali, Hong Shen, Xue Gu, Guangming Xu, Yingxue Ye, Xuefeng Yin

Abstract: 1,10 Phenanthroline (phen) has been tested as a complexing agent, which is more stable and selective than sodium-diethyldithiocarbamate (DDTC) and ammonium-pyrrolidinedithiocarbamate (APDC), for on-line pre-concentration of copper on RP-C-18 material in a microcolumn with a flow injection-flame atomic absorption spectrometer (Fl-FAAS) system. The on-line formed copper-phen complexes can be adsorbed on the C-18 sorbent material. Various parameters affecting the copper-phen complex formation and its subsequent adsorption on the microcolumn as well as its elution into the nebulizer of the atomic absorption spectrometer (AAS) were optimized. A 2.5 X 10^-3 mol/L phen in 2% ethanol was mixed on-line with aqueous sample solution acidified with 0.1% (v/v) nitric acid and flowed through the microcolumn for 30 seconds. The adsorbed copper-phen complexes in the microcolumn were eluted with ethanol for 10 seconds into the nebulizer of AAS. A good precision (RSD = 3.0%; n = 14), high enrichment factor (32) and sample throughput (80 samples h-1) with detection limit 0.3 µg/L were obtained. The method was applied to the standard reference materials such as sea water, mussels (biological), and GSS-1 (geological), for copper determination, and the results were in good agreement with the certified values.

"Sequential Injection Analysis System For The Determination Of Arsenic By Hydride Generation Atomic Absorption Spectrometry"
Fenxi Huaxue 2004 Volume 32, Issue 10 Pages 1365-1367
Yin Xuefeng, Zhang Jianjun, Wang Xiaofang

Abstract: A sequential injection system which consists of a syringe pump, a selector valve, a multi-port valve, a gas-liquid separator and a solenoid valve for the determination of arsenic by hydride generation atomic absorption spectrometry using tetrahydroborate as reductant was developed. The reduction time of sample with tetrahydoborate has increased by keeping the reactant in gas-liquid separator by using the solenoid valve. Various parameters affecting the performance of the sequential injection system were optimized, including reaction-time, carrier gas flow, sample volume, tetrahydroborate volume and concentration. Established sequential injection hydride generation technique was simple and automated operation. A sample throughput of 112/h was achieved with 400 µL samples with a precision of 2.0% RSD at 4 ?g/L As (n = 10) and a detection limit of 0.09 ?g/L. Good agreement with the certified values was obtained for the determination of arsenic in standard reference materials.

"Copper Determination After FI Online Sorbent Preconcentration Using 1-nitroso-2-naphthol As A Complexing Reagent"
Fresenius J. Anal. Chem. 1999 Volume 365, Issue 8 Pages 642-646
A. Ali, Y. Ye, G. Xu, X. Yin

Abstract: The suitability of 1-nitroso-2-naphthol as a complexing agent for online pre-concentration of copper using RP-C-18 material in a microcolumn with flow injection coupled with flame atomic absorption spectrometry (FI-FAAS) has been tested. Various parameters affecting complex formation, such as pH, sample flow rate, etc, and its elution into the nebulizer of FAAS were optimized. A 5 x 10^-3 mol/L reagent was online mixed with aqueous sample solution acidified with 0.1% (v/v) nitric acid (pH 3-4) and flowed through the microcolumn for 30 s. The adsorbed complexes in the microcolumn were eluted with ethanol in 10 a into the nebulizer of FAAS. A good precision (1.7% for 50 µg/L copper, n = 12), high enrichment factor (19) with detection limit (3s) 2.0 µg/L, and sample throughput (90 h-1) were obtained. The method was applied to certified reference materials seawater, mussel (biological), NBS-362 and NBS-364 (special low alloy steel), for the determination of copper, and the results were in good agreement with the certified values.
Extraction

"Determination Of Iron(II) And Total Iron Using Flow Injection On-line Preconcentration With FAAS"
Gaodeng Xuexiao Huaxue Xuebao 2000 Volume 21, Issue 3 Pages 350-353
XU Guang-Ming, YE Ying-Xue, YIN Xue-Feng, SHEN Hong, Akbar Ali

Abstract: A direct, rapid and sensitive method for the determination of Fe(II) and Fe(III) in water samples by flame absorption spectrometry coupled with flow injection on-line pre-concentration with 1,10-phenanthroline (1,10-phen) as the complex agent was developed. Various parameters affecting the complex formation and its subsequent adsorption, such as pH of the mixture solution, 1,10-phen concentration, sample flow rate etc. were optimized. A 2.5 X 10^-3 mol/L 1,10-phen in 2.0% ethanol was on-line mixed with aqueous sample solution of iron in 0.1% (volume ratio) hydrochloric acid and flowed through the microcolumn for 30 s. Fe(II) can be extracted as Fe(II)-phen complex in the C-18 microcolumn and determined within 10 s in the nebulizer of FAAS after being eluted by ethanol. Ascorbic acid (0.1 mg/mL) was used for the reduction of Fe(III) to Fe(II). A good precision (RSD = 1.1%, n = 10), high enrichment factor (19) and sample throughput (80 h) with detection limit 3 µg/L were obtained. The method has been successfully applied on the water sample for Fe(II) and Fe(III) determination with the recovery 94%-105%.

"1,10-phenanthroline As A Complexing Agent For Online Sorbent Extraction Preconcentration For Flow Injection-flame Atomic Absorption Spectrometry"
Anal. Chim. Acta 1999 Volume 392, Issue 2-3 Pages 283-289
Akbar Ali, Xuefeng Yin, Hong Shen, Yingxue Ye and Xue Gu

Abstract: 1,10-Phenanthroline (phen) has been tested as a complexing agent for online pre-concentration of copper, cadmium and cobalt, on RP-C-18 material in a microcolumn with a flow injection-flame atomic absorption spectrometric system. The online formed metal-phen complexes can be adsorbed on the C-18 sorbent material. Various parameters affecting complex formation and the subsequent complex adsorption in the microcolumn as well as its elution into the nebulizer of the spectrometer were optimized. A 2.5 x 10^-3 mol L-1 phen solution in 2% ethanol was mixed online with aqueous sample solution acidified with 0.1% (v/v) nitric acid to pH 5-6 and flowed through the microcolumn for 30 s. The adsorbed metal-phen complexes were eluted with ethanol in 10 s into the nebulizer. A good relative standard deviation (3.0%, 1.4%, 2.2% at 50, 50 and 100 µg L-1 n=14), high enrichment factors, 32, 32 and 22, with 3s detection limits of 0.3, 0.5 and 6.0 µg L-1 for Cu(II), Cd(II) and Co(II), respectively, and a sample throughput of 90/h were obtained. The method was applied to standard reference materials, i.e. seawater, mussel (biological) and GSS-1 (geological), for the determination of copper and cadmium; the results were in good agreement with the certified values.
Speciation

"Simultaneous Determination Of Trace Amounts Of Nickel, Copper And Mercury By Liquid Chromatography Coupled With Flow Injection Online Derivatization And Preconcentration"
Anal. Chim. Acta 1998 Volume 369, Issue 3 Pages 215-223
Akbar Ali, Hong Shen and Xuefeng Yin*

Abstract: Reversed phase liquid chromatography (LC) combined with flow injection (FI) online derivatization and pre-concentration resulted in a sensitive technique for analyzes of multi-metals at trace levels. A new home-designed micro-pre-concentration column containing RP-C18 material as solid sorbent, accommodated in a pressure-tight housing of stainless steel, combined with an LC six port valve was used to interface the flow injection online derivatization and pre-concentration system to the LC equipment. This pre-concentration column, which can be used for online derivatization and pre-concentration using peristaltic pump, proved to be strong enough to bear the high pressure of the LC eluent. Based on this FI-LC system, a method for the determination of Ni(II), Cu(II), and Hg(II) in water samples as their diethyldithiocarbamate (DDC) complexes was developed. A MeOH/H2O mixture (80:20 v/v) as LC eluent and intelligent UV detector programmed in time for absorption measurement at the max. absorption wavelength of the respectively. metal-DDC complexes were used. The detection limits were (signal : noise = 3) 0.16, 0.41 and 1.1 µg L-1 for Ni, Cu and Hg, respectively.; and the relative standard deviations were 3.6, 4.5 and 3.9% for Ni(II) (0.10 mg L-1), Cu(II) (0.10 mg L-1) and Hg(II) (0.40 mg L-1) (n = 6), respectively. The developed method was successfully applied to wastewater samples from an elec. power station and a machine tool factory and the results agreed with values determined by atomic absorption spectrometry.
Nickel Copper Mercury Industrial HPLC Spectrophotometry Method comparison Preconcentration Pre-column derivatization