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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Classification: Alloy -> copper

Citations 19

"Amperometric Determination Of Hydrogen Peroxide In Pickling Baths For Copper And Copper Alloys By Flow Injection Analysis"
Anal. Chim. Acta 1983 Volume 145, Issue 1 Pages 189-196
Hans Lundbäck

Abstract: The hydrogen peroxide is oxidized at + 1.5 V vs. SCE at a glassy carbon electrode of the wall-jet type. The samples are diluted about 100 times in a dispersion coil before entering the amperometric detector. The calibration curve is linear from 10^-4 to 1 M H2O2, when 5 µL samples are used. With 50 µL samples the detection limit decreases to 10^-6 M H2O2. Neither metal ions (Cu2+, Zn2+, Ni2+, Al3+) up to 0.5 M nor changes in the sulfuric acid concentration of the samples between 0.1 and 1 M interfere with the hydrogen peroxide determination. About 75 samples can be analyzed per hour.
Hydrogen peroxide Amperometry Electrode Electrode

"Flow Injection Spectrophotometric Determination Of Copper Using Bis(cyclohexanone)oxalyldihydrazone"
Anal. Chim. Acta 1995 Volume 304, Issue 1 Pages 97-100
N. Chimpalee, D. Chimpalee, S. Srithawepoon, T. Patjarut and D. Thorburn Burns*

Abstract: A sample (250 µL) was injected into a water carrier stream (1.35 ml/min) which was then sequentially merged with streams (1.35 ml/min) of 27% citric acid solution, 37% ammonia solution and 0.18% bis(cyclohexanone)oxalyldihydrazone solution then passed through a reaction coil (4 m x 0.8 mm i.d.) to a detector cell with detection at 600 nm. The calibration graph was linear up to 20 µg/ml Cu; the detection limit was 1.3 µg/ml and RSD was 0.92% (n = 10). The method was applied to the determination of Cu in steels, copper-based alloys and pig feeds and to copper monitoring in an alkaline scale-removal process.
Copper Spectrophotometry Complexation

"Applications Of A Slotted Tube Atom Trap And Flame Atomic Absorption Spectrometry: Determination Of Bismuth In Copper-based Alloys With And Without Hydride Generation"
Anal. Chim. Acta 1995 Volume 311, Issue 1 Pages 93-97
D. Thorburn Burns*, Narong Chimpalee and Michael Harriott

Abstract: Improved systems are reported for the determination of bismuth (0-0.1%, w/w) in copper-based alloys by flame atomic absorption spectrometry. The use of a slotted quartz tube atom trap (STAT) with nebulised solutions or coupled with hydride generation decreases the characteristic concentrations (nebulized solution, 0.44/0.25, without/with STAT; hydride, 0.022/0.014, without/with STAT) and improved precisions by factors of two compared with those obtained without the use of the STAT. Determination of bismuth in a series of reference materials demonstrates the usefulness of STAT systems for the analysis of metallurgical samples.
Bismuth Spectrophotometry Method comparison

"Flow Injection Extraction-spectrophotometric Determination Of Copper Using Bis(acetylacetone)ethylenediimine"
Anal. Chim. Acta 1996 Volume 331, Issue 3 Pages 253-256
N. Chimpalee, D. Chimpalee, S. Lohwithee, L. Nakwatchara and D. Thorburn Burns*

Abstract: Sample (250 µL) was injected into a water carrier stream (1.4 ml/min) which was then merged sequentially with acetate buffer of pH 5 (1.4 ml/min), 0.2% bis(acetylacetone)ethylenediimine in aqueous 10% ethanol (1.4 ml/min) and CHCl3 (1 ml/min). The mixture was passed through an extraction coil (400 cm x 0.8 mm i.d.) to a phase separator. The organic phase was fed to the spectrophotometric detector where the absorbance was measured at 370 nm. The calibration graph for Cu was linear for up to 100 µg/ml, the detection liwas 0.42 µg/ml and the RSD (n = 10) for 20 µg/ml Cu was 1.95%. The method was applied to Cu-based alloys and pig feeds. The results for the alloys were in agreement with the certified values and those for pig feed were confirmed by AAS. The sampling rate was 20/h.
Copper Spectrophotometry Sample preparation Buffer Reference material Method comparison Extraction Organic phase detection Phase separator

"Continuous Spectrophotometric Determination Of Copper, Nickel, And Zinc In Copper-base Alloys By Flow Injection Analysis"
Talanta 1981 Volume 28, Issue 6 Pages 389-393
Rokuro-Kuroda* and Tadashi Mochizuki

Abstract: Flow-injection methods have been developed for the determination of copper, nickel and zinc in copper-base alloys, including several types of brasses, deoxidized copper, beryllium copper and German silver. The system for copper and nickel involves the measurement of the absorbance of the copper(II) and nickel(II) aquo-complexes at 805 and 410 nm, respectively, after simple dissolution of the sample in a nitric acid-phosphoric acid mixture. The system needs no further reagents and the sample solutions can be analyzed at rates of up to 280 /hr for copper (or nickel in German silver) without any carry-over. The system for zinc consists of automatic dilution of the injected sample with a thiosulphate-acetate buffer solution and the subsequent measurement of the absorbance of the zinc-Xylenol Orange complex at 568 nm. This system permits analysis rates of up to 90/hr for zinc solutions, with no carry-over. The procedures have been applied to standard copper-base alloys. The results agreed satisfactorily with the certified values. The precision ranges are 0.2-0.7% for copper and nickel and 0.5-0.8% for zinc.
Copper Nickel Zinc Spectrophotometry

"Novel Ferroin Membrane Sensor For Potentiometric Determination Of Iron"
Talanta 1994 Volume 41, Issue 6 Pages 891-899
Saad S. M. Hassan* and Sayed A. M. Marzouk,

Abstract: Sodium tetraphenylborate solution (10 mM) and 10 mM ferroin [tris-(1,10-phenanthroline)iron(II)] were mixed for 5 min and the precipitate was collected, washed with water, dried for 24 h and finely ground. The powder was mixed with 2-nitrophenyl phenyl ether, PVC and THF, the solvent evaporated overnight and the resulting 0.1 mm thick membrane was fitted into a sandwich FIA cell. A Ag/AgCl internal reference wire electrode was immersed in a 10 mM ferroin/10 mM NaCl (1:1) internal reference solution The test solution was injected into a stream of 5 mM 1,10-phenanthroline and 10% hydroxylammonium chloride in 0.1 M acetate buffer of pH 4.7 in a FIA system, the solution passed through a mixing coil into a sandwich cell. The calibration graph was linear for 1-100 µM-ferroin, allowing the determination of total Fe. Fe(II) was determined batchwise by the omission of the hydroxylammonium chloride and the addition of EDTA. The removal of interfering anions is discussed. The method was applied to the determination of Fe in tap, underground, sea and mineral water, Al- and Cu-based alloys, cement, rocks and pharmaceutical preparations (details given). The recovery of 300 µg of Fe was 101.9% with RSD (n = 10) of 1.1%.
Iron Electrode Sensor Potentiometry Membrane Interferences

"Automated Flow Injection Spectrophotometric Determination Of Zinc Using Zincon: Applications To Analysis Of Waters, Alloys, And Insulin Formulations"
Analyst 1986 Volume 111, Issue 11 Pages 1311-1315
Michael A. Koupparis and Paraskevi I. Anagnostopoulou

Abstract: Water samples were filtered (0.45 µm membrane filter) followed by adjustment of the filtrate to pH 9 with 0.5 M borate buffer. Copper alloy samples were dissolved in concentrated HNO3 (10 ml), and the solution was diluted, neutralized with 5 M NaOH to phenolphthalein, and diluted with 0.05 M borate buffer. Insulin formulations were deproteinized with 1 M HCl (1 ml) and 0.61 M trichloroacetic acid (8 ml). After centrifugation, the supernatant solution (2 ml) was neutralized with 1 M NaOH (2 ml) and diluted to 10 mL with 0.05 M borate buffer. Aliquots (300 µL) of test solution containing <10 µg mL-1 of Zn were injected into a stream of mixed reagent (0.01 M KCN - 0.1 M ascorbic acid in borate buffer solution) at pH 9. After passing through a 150-cm mixing coil, the stream was mixed with a second reagent stream (10% cyclohexanone - aqueous 0.016% zincon in borate buffer solution) at pH 9. After reaction, the absorbance was measured at 620 nm with a detection limit of 0.05 µg mL-1 of Zn. Results were in agreement with reference values for the alloys by AAS.
Zinc Clinical analysis Spectrophotometry Method comparison Reference material

"Rapid Continuous Determination Of Aluminum In Copper-base Alloys By Flow Injection Spectrophotometry"
Fresenius J. Anal. Chem. 1982 Volume 311, Issue 1 Pages 11-15
Tadashi Mochizuki and Rokuro Kuroda*

Abstract: A flow-injection spectrophotometric method has been developed for the rapid, continuous determination of aluminium in copper-base alloys. The system consists of the masking of copper, zinc, iron, etc. with a combined use of thiourea, ascorbic acid and EDTA and the measurement of light absorption of aluminium-Xylenol Orange complex at 506 nm. With appropriate standardization satisfactory results are obtained in spite of sluggish reaction of aluminium and Xylenol Orange. The system allows the analysis of solutions of copper-base alloys for aluminium to be conducted at a rate of 50 determinations per hour without any carryover. The results obtained for standard brasses and aluminium bronze (Al 1.43-10.2%) agreed well with the certified values. The precision (rsd) ranges are 0.2-0.3%.
Aluminum Spectrophotometry

"Determination Of Lead In Copper-based Alloys Using A Modified Quartz Atom Trap And Flow Injection Flame Atomic Absorption Spectrometry"
Fresenius J. Anal. Chem. 1989 Volume 335, Issue 6 Pages 566-567
D. Thorburn Burns, N. Chimpalee and M. Harriott

Abstract: Copper alloy (0.1 to 0.5 g) is dissolved in 4 mL of concentrated HCl and 2 mL of concentrated HNO3 and the solution is diluted to 100 mL with water. A 250 µL aliquot of solution is injected into a flow of water (7.2 mL min-1) via a mixing coil (10 cm x 0.8 mm) into the described apparatus (Anal. Abstr., 1989, 51, 1B96) and aspirated at 6.9 mL min-1 into an air - acetylene flame; the absorbance is measured at 283.3 nm. The calibration graph is rectilinear up to 10 µg mL-1 of Pb. No interference is observed. The method is less sensitive (detection limit 0.13 vs. 0.09 µg mL-1) than the conventional direct aspiration method, but is faster (200 vs. 50 samples h-1), the life of the quartz tube atom trap is extended, and the necessity of cleaning of the trap is reduced.
Lead Spectrophotometry Apparatus Interferences Interface

"Analysis Of Copper Content In Alloy Copper By A Combination Of Electrography And Flow Injection Analysis"
Am. Lab. 1998 Volume 30, Issue 2 Pages 30-30
Zhan, X.;Jiang, X.;He, D.

Abstract: The combination of electrog. and flow injection analysis was proposed to determine the Cu content in copper alloys.
Copper Chromatography Electrochemical analysis

"Rapid Determination Of Copper In Various Copper Base Alloys By Flow Injection Analysis"
Bunseki Kagaku 1980 Volume 29, Issue 10 Pages T73-T78

Abstract: A flow injection method is described for the spectrophotometric determination of copper in various types of copper-base alloys. The system utilizes either the light absorption of aquacopper(II) ion at 805 nm or the light absorption of colored complex of copper(II) with EDTA (730 nm). Simple dissolution of alloys in nitric acid in the presence of tartaric acid suffices for sample preparation. The procedures have been applied to standard samples of copper-base alloys including several types of brasses, beryllium copper, deoxidized copper, German silver and aluminum bronze. The results obtained agree very satisfactorily with the certified values for these alloys. The precision is better than 0.5 % for the aquacopper(II) ion method. The sampling rate is 1 7 samples per hour.
Copper Spectrophotometry Method comparison Reference material

"Direct Fluorometric And Flow Injection Fluorometric Methods For The Determination Of Trace Phosphorus"
Fenxi Ceshi Xuebao 1998 Volume 17, Issue 3 Pages 77-79
Song Gongwu, Feng Jian

Abstract: Direct fluorometric determination of trace P is based upon the quenching of the fluorescence of rhodamine 6G due to the formation of a nonfluorescent hetero-polynuclear acid of rhodamine-phosphoro-Mo ion-associates. The excitations wavelength is 350 nm, while the maximum emission wavelength is 555 nm. The flow injection fluorometric variant of this method has the advantages of high sensitivity, good selectivity and simplicity. It was satisfactorily employed for the determination of P in Cu alloys, steel, and Mn ores.
Phosphorus Fluorescence Quenching Indirect Ion pair formation

"Determination Of Trace Arsenic In Copper Alloy By Online Flow Injection - Hydride-generation Inductively Coupled Plasma Atomic-emission Spectrometry"
Fenxi Huaxue 1994 Volume 22, Issue 8 Pages 816-818
Wang, H.N.;Chen, Y.

Abstract: Sample (1 g) was decomposed with 6 mL HNO3 and the pH was adjusted to 1 and diluted to 100 mL with water. The solution was injected into the analysis system and transferred by a stream of water at 1.6 ml/min to a column (5 cm x 5 mm i.d.) of cation-exchange resin and eluted with 2.2 M HCl at 4.4 ml/min; the eluate was mixed with 2.2 M HCl at 1.6 ml/min treated with 1% NaBH4 at 1 ml/min. The generated hydride was directly determined by ICP with measurement at 228.8 nm. The detection limit was 0.9 µg/g. Interference from up to 10 mg/ml of Cu(II) could be eliminated. Recovery was 102-104%. Sampling frequency was 25 runs/h.
Arsenic Ion exchange Spectrophotometry Volatile generation Interferences Resin Volatile generation

"Simultaneous Determination Of Aluminum And Iron In Copper-base Alloy By Flow Injection-spectrophotometry"
Fenxi Shiyanshi 1998 Volume 17, Issue 3 Pages 53-56
Qu, X.;Zhou, J.;Yin, H.;Sun, Y.

Abstract: A flow injection-spectrophotometric method is proposed for the simultaneous determination of Al and Fe with Chromazurol (CAS) and cetyltrimethylammonium bromide (CTAB). Al and Fe were determined by measuring respectively the single absorbance of Al(III)-CAS-CTAB and the total absorbance of Al(III)-CAS-CTAB and Fe(III)-CAS-CTAB at 628 nm with appropriate calculation. Under optimal conditions, the detection limits are 1.69 x 10^-3 mg/L (Al) and 1.73 x 10^-3 mg/L (Fe) and the sampling rate is 60 samples/h. This method was applied to the simultaneous determination of Al and Fe in reference samples with satisfactory results.
Aluminum Iron Spectrophotometry Simultaneous analysis Optimization Complexation

"Flow Injection Analysis Fluorescence Quenching Method For Determination Of Trace Phosphorus(V) And Silicon(IV)"
Fenxi Yiqi 1998 Volume 1998, Issue 2 Pages 50-52
Song, G.;Fang, G.

Abstract: A flow injection-fluorometric method was established for determining P(V) and Si(IV) based on the fluorescence quenching effect of rhodamine 6G due to the formation of ion-association complex in acid medium. Optimal conditions were determined The calibration curves were linear at 0-80 µg/L for P(V) and Si(IV). The method was used for the determination of P(V) and Si(IV) in samples of steel and Cu alloy with satisfactory results.
Phosphorus(V) Silicon(IV) Fluorescence Indirect Optimization Ion pair formation Quenching

"Elimination Of Interferences In ICP-AES By Flow Injection Gradient Technique-generalized Standard Addition Method"
Gaodeng Xuexiao Huaxue Xuebao 1989 Volume 10, Issue 12 Pages 1185-1188
Luo Jianbo, Zhang Zhanxia, Qian Haowen, Cai Mingxiang

Abstract: A method based on a flow injection gradient technique (FIGT) and generalized standard addition method (GSAM) is developed for the elimination of matrix and/or spectral interferences in inductively coupled plasma atomic emission spectrometry (ICP-AES). Only one standard for an analyte is used to obtain the signals required for the evaluation in the GSAM. Operating parameters, including the carrier flow rates and residence times, are discussed in detail. To assess the proposed method, two synthetic samples, two types of Cu alloys and steel were analyzed for Zn, Mn, and As respectively. The relative standard deviations are 0.5-1.9%.
Zinc Manganese Arsenic Spectrophotometry Gradient technique Interferences Standard additions calibration

"Flow Injection Analysis For Trace Phosphorus Determination With Fluorescence Quenching Of Rhodamine 6G With Phosphomolybdate"
Guangpuxue Yu Guangpu Fenxi 1991 Volume 11, Issue 3 Pages 59-61
Song, G.

Abstract: Copper alloys are heated to dissolution in 8 mL of HCl (1:8) and 2 mL of 30% H2O2, followed by gentle boiling for 4 min, concentration to ~4 ml, cooling and addition of 0.5 mL of 1.84 M H2SO4 and dilution with water to 50 mL. A 500 µL aliquot of the resulting solution is injected into a carrier stream of water (2.5 mL min-1) and flows to a reaction tube (50 cm x 0.8 mm i.d.) to mix with a stream (2.5 mL min-1) of reagent solution [containing 75 mM H2SO4, 0.81 mM (NH4)2MoO4, 13.4 µM-Rhodamine 6G and 0.1% poly(vinyl alcohol)] before detection at 555 nm (excitation at 350 nm). Linear relationship is observed for 0 to 80 ppb of P; detection limit is 0.343 ppb. When determining 80 ppb of P, interference from As(V) can be eliminated by addition of Na2SO3 - Na2S2O3. Results are satisfactory and compared with those obtained by fluorescence colorimetry. The method has also been applied to steels and Mn ores, with coefficient of variation of 0.7 to 1.4%.
Phosphorus Fluorescence Interferences PPB Quenching

"Simultaneous Determination Of Iron And Aluminum With Flow Injection-standard Addition Dual Wavelength Spectrophotometry"
Lihua Jianyan, Huaxue Fence 1998 Volume 34, Issue 5 Pages 195-197
Qu Xiangjin,Zhou Jie, Sun Yanhua, Zhang Changjun

Abstract: A method for the simultaneous determination of Fe and Al with CAS (Chrome Azurol S) as chromogenic reagent in the presence of CTMAB by FIA standard addition DW-spectrophotometry was presented. The chromogenic reaction of CAS with Fe or Al was carried out in pH 6.75 NH4AcO buffer solution The determining wavelength pairs were: Fe, 629 nm and 587 nm, and Al, 612 nm and 646 nm. Under optimum conditions, the detection limits were: Fe, 0.001 µg mL-1, and Al, 0.002 µg mL-1, and Beer's law was obeyed at Fe, 0-1.2 µg mL-1, and Al, 0-0.8 µg mL-1. The recoveries were: Fe, 98.6-102.0%, and Al, 98.1-100.4%. The sampling rate of the FIA system was 60 samples per h. The interference of Cu(II) can be masked by thiourea. The method was applied to determine Fe and Al in Cu alloys with relative standard deviation: Fe, 0.30-0.41%, and Al, 0.15-1.1%.
Iron Aluminum Spectrophotometry Simultaneous analysis Standard additions calibration Multivariate calibration Optimization Interferences

"Spectrofluorimetric - Extraction Determination Of Beryllium With 2-methyl-8-hydroxyquinoline Using Flow Injection Analysis. Determination Of Beryllium(II) In Alloys"
Quim. Anal. 1991 Volume 10, Issue 4 Pages 347-354
Martin Esteban, A.;Fernandez, P.;Perez Conde, C.

Abstract: Sample solution containing 0.3 µg mL-1 of Be(II) was injected into a carrier stream of 0.5 M NH4Cl - NH3 which merged with a 0.09% solution of 2-methyl-8-hydroxyquinoline in aqueous 15% acetone. The complex formed was extracted into CHCl3 before fluorimetric detection at 520 nm (excitation at 400 nm). The calibration graph was rectilinear up to 0.3 ppm of Be and the limit of detection was 0.13 ppb. IronIII, Al(III), Ni(II), Zn(II) and Cu(II) interfere. The method has been used to determine Be in Cu-based alloys.
Beryllium Fluorescence Sample preparation Extraction Interferences PPB