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

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Inorganic compound

Classification: Inorganic compound -> sodium chloride

Citations 7

"The Vibrating Wire Electrode As An Amperometric Detector For Flow Injection Systems"
Anal. Chim. Acta 1983 Volume 148, Issue 1 Pages 87-101
Kenneth W. Pratt, Jr. and Dennis C. Johnson

Abstract: The application of vibrating wire electrodes for amperometric detection in flow-injection systems is reported. Equations of response for these electrodes in a flow-through cell are derived and verified experimentally. The applicability of the equation for other convective detectors in flow-through cells is discussed. A detection limit of 5 x 10^-10 M iodide and a linear dynamic range of 6.3 decades were obtained for a platinum vibrating wire electrode.
Iodine Amperometry Electrode Apparatus Theory

"Determination Of Bromide In Sodium Chloride Matrices By Flow Injection Analysis Using Blank Peak Elimination And Kinetic Discrimination"
Anal. Chim. Acta 1993 Volume 272, Issue 2 Pages 245-250
W. J. M. Emaus* and H. J. Henning

Abstract: The cited determination was based on oxidation of bromide to bromine using chloramine T, with subsequent reaction of the bromine with phenol red to give bromophenol blue which is measured spectrophotometrically at 590 nm. The FIA manifold used is illustrated (flow rates etc. given); short reaction times offered by FIA prevented the interference of chloride. The influence of peak blanks, which appear because of differences in refractive indices between the aqueous carrier solution and sample solution was eliminated by using a large sample volume The method was applied to the determination of 0.5 to 10 mg L-1 of bromide in NaCl solution (300 g l-1). The limit of quantification was 1.0 mg of Br kg-1 with a coefficient of variation of 1% at when determining 30 to 50 mg of Br kg-1. Analysis time was ~60 s. The method was applied to the analysis of brine used as starting material in the chlor-alkali industry.
Bromide Spectrophotometry Kinetic Interferences

"Enzymatic Determinations With Rotating Bioreactors: Determination Of Glutamate In Food Products"
Anal. Chim. Acta 1998 Volume 369, Issue 1-2 Pages 147-155
Chitra Janarthanan and Horacio A. Mottola*

Abstract: The benefits of using rotating bioreactors for online or inline determination in food analyzes are illustrated with the determination of L-glutamate. Two enzymatic approaches have been implemented and samples used to illustrate the approaches included: beef and chicken bouillon cubes, soy sauce, chicken broth, seasoning salt, fruit and vegetable juices, and skim milk. One of the methods uses glutamate dehydrogenase (EC in the main enzymatic reaction and diaphorase (EC in the indicator reaction, which involves NADH and hexacyanoferrate(III). The monitored species, amperometrically detected at a platinum-ring electrode, is the hexacyanoferrate(II) produced by the indicator reaction. The second method utilizes a single enzyme, glutamate oxidase (EC, and amperometric monitoring of a product of the enzymatic reaction, H2O2, also at a platinum-ring electrode. Interference by ascorbate present in some samples is eliminated by inline use of a packed reactor containing ascorbate oxidase (EC The relative merits of both systems when using continuous-flow/stopped-flow/continuous-flow processing are discussed.
Glutamate Amperometry Electrode Interferences Immobilized enzyme Stopped-flow Manifold comparison

"Design Of A New Phase Separator For Liquid-liquid Extraction In Flowing Systems"
Microchem. J. 1996 Volume 53, Issue 2 Pages 147-151
N. Maleki, B. Haghighi and A. Safavi

Abstract: A simplified and effective phase separator (PS) was developed (schematic shown) for use in flow systems and used for the determination of iodide (I). Portions (300 µL) of standard I solutions were injected into a carrier stream of water in a flow injection system and mixed with a stream of Fe3+ in HNO3 in a mixing coil. The I2 produced in the mixed phase was extracted by a continuous stream of CCl4 at 1.1 ml/min. The organic phase was separated from the aqueous phase using the PS and the absorption of the extracted I2 in the organic phase was measured spectrophotometrically at 517 nm. The calibration graph was linear up to 40 µg/ml of I and the detection limit was 0.337 µg/ml. A sample throughput of 34 samples/h was achieved with an RSD (n = 8) of 1.3%. The method was applied to the analysis of I in an NaCl sample with recoveries of 86.5-105.5% and RSD (n = 8) of 1.33-2.88. Results agreed well with the manufacturer's certified values.
Iodide Spectrophotometry Sample preparation Phase separator Organic phase detection Reference material Solvent extraction

"Spectrophotometric Determination Of Magnesium(II) By Flow Injection Analysis Using Succinimide Dioxime"
Analusis 1987 Volume 15, Issue 3 Pages 136-139
Forteza, R.;Cerda, V.;Maspoch, S.;Blanco, M.

Abstract: The method was based on the inhibition by Mg of the formation of the blue product of the Mn(II)-catalyzed oxidation of succinimide dioxime(I). The sample solution (125 µL) was injected into a stream (0.45 mL min-1) of 0.02 M nitrilotriacetic acid in 13 mM NaOH as masking agent for alkaline-earth metals. This stream was mixed in a 0.5-m coil with a stream containing I (1 g l-1) and Mn(II) (4 mg l-1). The mixed streams were introduced into a stream of 1.5 M NaOH (0.9 mL min-1) in a 4-m coil at 35°C and the absorbance of the solution was measured at 695 nm. Calibration graphs were rectilinear from 0.5 to 8 mg L-1 of Mg. For 5 mg L-1 of Mg, the coefficient of variation was 2% (n = 12) and there was no interference from up to 150, 150 or 300 mg l-1, of Ca, Sr or Ba, respectively. The tolerance limits of nine other cations and 13 anions were also determined. The method was applied to drinking water and common salt, giving results which agreed with those of AAS.
Magnesium(II) Spectrophotometry Catalysis Heated reaction Interferences Method comparison Indirect

"Simultaneous Multi-element Analysis And Matrix Effect Of Sodium Chloride By Flow Injection ICP-AES"
Guangpuxue Yu Guangpu Fenxi 1991 Volume 11, Issue 5 Pages 32-37
Zhang, Z.;Zeng, X.

Abstract: The determination of Cd, Cr, Fe, Mn, Ni, V, Ca, Co, Cu, Mg and Zn by ICP-AES combined with flow injection analysis. The best coefficient of variation and detection limits were obtained with 5- or 10-s integral times. The effects of a NaCl matrix on the elements were studied. The results show that the flow injection technique could reduce analytical signal drift and improve determination reproducibility. The matrix effects of NaCl varied with different r.f. power and the matrix effect of NaCl existed mainly in the evaporation - atomization - excitation process in the ICP.
Cadmium Calcium Chromium Cobalt Copper Iron Magnesium Manganese Nickel Vanadium Zinc Spectrophotometry Multielement Signal drift Interferences

"An Experiment In The Sampling Of Solids For Chemical Analysis"
J. Chem. Educ. 1998 Volume 75, Issue 8 Pages 1028-1033
Robert D. Guy , Louis Ramaley and Peter D. Wentzell

Abstract: An experiment was developed to show students taking the anal. chemical lab. at the third-year level the limitations imposed by sampling in a real chemical anal. problem. The molybdenum-blue method is employed for the determination of phosphate in the presence of sodium chloride and, to facilitate rapid anal., the method is implemented as a flow injection analysis technique.
Phosphate Spectrophotometry Education