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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King Chuen Lin

Abbrev:
Lin, K.C.
Other Names:
King-Chuen Lin
Address:
Department of Chemistry, National Taiwan University, P. O. Box 23-24, Taipei, Taiwan, China
Phone:
NA
Fax:
+886-2-2362-1483

Citations 6

"Detection Of Iron Species Using Inductively Coupled Plasma Mass Spectrometry Under Cold Plasma Temperature Conditions"
Spectrochim. Acta B 2001 Volume 56, Issue 1 Pages 123-128
Li-Shing Huang and King-Chuen Lin

Abstract: Under the conditions of low radio frequency (rf) power of 600 W and aerosol gas flow rate of 1.25-1.35 l/min, 56Fe (or 54Fe) ions can be detected from the isobaric interference of the ArO+ (or ArN+) matrix. Using this method, the detection limit of 56Fe can reach 16 ng/l (ppt), 60 times smaller than by normal plasma conditions at 1200 W rf power. The linear dynamic range of the analyte measurement extends to 1000 ng/ml (ppb).

"Laser-enhanced Ionization And Laser-induced Atomic Fluorescence As Element-specific Detection Methods For Gas Chromatography - Application To Organotin Analysis"
J. Chromatogr. A 2001 Volume 921, Issue 2 Pages 247-253
Ching-Bin Ke, King-Dow Su and King-Chuen Lin

Abstract: We have demonstrated that flame laser-enhanced ionization (LEI) and flame laser-induced atomic fluorescence (LIAF) techniques can be used as, alternative sensitive detectors for gas chromatographic (GC) analysis of organotin compounds. These two element-specific detection methods are free from interferences from the organic solvent. Two types of LEI schemes for Sn detection are employed. For the two-step LEI scheme (TLEI), the tin atoms in the flame were stepwise excited and then ionized collisionally. In contrast, in detection with the single-step LEI scheme (SLEI), only one dye laser is used. For the analysis of tetramethyltin and tetraethyltin, the GC-TLEI, GC-SLEI, and GC-LIAF systems yield Linear dynamic ranges of 0.015-400, 0.39-600 and 0.5-600 ng, respectively. The corresponding detection limits reach 0.15, 3.9 and 5.0 mg/l, with absolute quantities corresponding to 15, 390 and 500 pg, respectively, for an injection volume of 0.1 µL. These detection methods prove to be more sensitive and selective than the conventional flame ionization detection, which achieves absolute detection limits of 800 and 1667 pg for tetraethyltin and tetramethyltin, respectively, under identical GC conditions. (C) 2001 Elsevier Science BN. All rights reserved.
Preconcentration

"Application Of Laser-enhanced Ionization Spectroscopy: Effect Of Dissociation Constant On The Atomization Efficiency Determination In An Acetylene-air Flame"
J. Chin. Chem. Soc. 2001 Volume 48, Issue 6A Pages 977-981
Ching-Bin Ke, Shiue-Ing Lu and King-Chuen Lin

Abstract: By using laser-enhanced ionization (LEI) technique, we have studied atomization efficiencies of the alkali halides in an acetylene/air flame. As an aqueous solution of the metal salt was nebulized into the burner head, a flame with a high temperature of about 2500 K may cause dissociation of the ionic bond to release the free metal atoms. The ratio of the number density of free metal atoms present in the flame to the total number density of the same metal element nebulized determines the atomization efficiency. In this work, binary salt solutions including LiX, NaX, and KX (X=Cl, Br, and I) were used; each was prepared at 5 ppm (mug/mL) metal concentration. The atomization efficiency of the metal element was measured, as the accompanied halogen species was varied. We found that the ratios of atomization efficiencies of the alkali element in different halide compounds were almost equal to one. Atomization efficiency determination is dominated by the metal atom, but weakly influenced by the binding halogen species. The observation may be interpreted satisfactorily by using the Sugden-Bulewicz model. Based on this model, the metal atomization efficiency for different halide compounds depends on the number densities of the halogen atoms and the related dissociation constants. For the binary salt with a small concentration and a large dissociation constant, the atomization efficiency determination tends to be dominated by the metal atom alone.

"Flow Injection Inductively Coupled Plasma Mass Spectrometer Incorporated With An Ultrasonic Nebulizer-membrane Dryer: Application To Trace Lead Detection In Aqueous Solution And Seawater"
Appl. Spectrosc. 2001 Volume 55, Issue 5 Pages 604-610
Su-Hui Ke, Li-Shing Huang, Jer-Shing Huang, and King-Chuen Lin

Abstract: Flow injection (FI) incorporated with inductively coupled plasma mass spectrometry (ICP-MS) was used to determine lead in aqueous solutions and seawater. Lead was retained in the form of Pb-DDPA complex in a sorbent microcolumn packed with C-18-bonded silica, and then carried to an ultrasonic nebulizer with methanol as eluent. The ultrasonic nebulizer removed about 66% of methanol solvent vapors from entering the detector. A multi-tube Nafion (R) membrane dryer, installed along the passage prior to the ICP torch, further removed 50% of methanol. Reducing the amount of methanol solvent significantly improved the signal-to-background ratio of the detector. Accordingly, when the sample was Loaded for 15 and 60 s, respectively, Pb detection limits were determined to be 0.162 and 0.028 ng/L, one to two orders of magnitude lower than those reported. The enrichment factors were also measured to be 7 and 28, with the sampling frequencies of 31 and 21 hr-1, respectively, The method was applied for the determination of Pb in a reference seawater. The obtained result was 0.013±0.001 ng/mL, consistent with the certified value of 0.013±0.005 ng/mL.
Knotted reactor

"Laser-enhanced Ionization Detection Of Pb In Seawater By Flow Injection Analysis With Online Preconcentration And Separation"
Anal. Chem. 1999 Volume 71, Issue 8 Pages 1561-1567
Ching-Bin Ke and King-Chuen Lin

Abstract: The flame laser-enhanced ionization (LEI) technique is coupled with a flow injection analysis system to measure the trace Pb concentrations in aqueous solution and seawater. A flow injection (FI) manifold is incorporated with a micro-column packed with a C18 bonded silica. The chelating agent, DDPA, forms a Pb-DDPA complex, which may be sorbed in the micro-column then eluted with methanol. Preconcentrated Pb is then detected by the LEI technique with single-or 2-step excitation. At 5 and 15 mL volume-fixed sample loading, detection limits of 0.011 and 0.0033 ng/mL (11 and 3.3 ppt) and enrichment factors of 16 and 48 are achieved, respectively, using a two-step FI-LEI. Sensitivity of this system proved to be better by at least 1 order of magnitude than that of the conventional LEI method; FI-LEI also increases the tolerance of matrix interference. The LEI signal is slightly reduced to 80% intensity as 10,000 µg/mL (ppm) Na and K matrixes are mixed in the Pb solution Resistance to alkali matrixes is enhanced ~4 times than that reported previously using a similar water-immersed probe as a LEI collector. The FI-LEI was used for the first time to determine Pb content of seawater, achieving a result of 0.0112 ± 0.0006 ng/mL (ppb) consistent with the certified value of 0.013 ± 0.005 ng/mL (ppb).
Knotted reactor Laser

"Novel Technique To Reduce Electrical Inference Inherent In Laser-enhanced Ionization Detection By Using Flow Injection Analysis"
Anal. Chem. 1994 Volume 66, Issue 13 Pages 2180-2186
Shau-Chun Wang and King-Chuen Lin

Abstract: Aqueous solutions of In containing 0.1-50 ppm of Na were nebulized at 4.5 mL/min into an acetylene-air flame. Analytes were ionized with a tunable dye laser, pumped by a Nd:YAG laser at 532 nm, and doubled through a KDP crystal with 325.62 nm emission. Data collection was achieved under non-optimum conditions with two metal rod electrodes suspended in the vicinity of the flame, one electrode being biased at -1000 V, the other linked to a current-to-voltage current amplifier. Calibration graphs were linear up to 10 ppm of In in matrices containing 0-2 ppm of Na. Analyses of a synthetic sample containing 2 ppm of In and 1 ppm of Na had a RSD of 3.6% (n = 3). Comparative analyzes were performed using FIA with carrier solutions of the analyte/matrix being analyzed with a 250 µL injection of water. In this case, calibration graphs were linear over same range, but with a greater amount of tolerated matrix (from 4-40 ppm of sodium). Results are discussed.
Indium Environmental LIBS