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: Geological -> rock

Citations 44

"An Online Solid Phase Extraction System Using Polyurethane Foam For The Spectrophotometric Determination Of Nickel In Silicates And Alloys"
Anal. Chim. Acta 1999 Volume 378, Issue 1-3 Pages 287-292
Sérgio Luis Costa Ferreira, Djane Santiago de Jesus, Ricardo Jorgensen Cassella, Antonio Celso Spinola Costa, Marcelo Souza de Carvalho and Ricardo Erthal Santelli

Abstract: The present paper describes the use of a solid phase extraction system using a polyurethane foam (PUF) minicolumn, in order to separate nickel from interferences due to other elements and determine it by flow injection analysis with spectrophotometric detection. Separation is based on the retention of thiocyanate complexes of interferent ions in the PUF minicolumn. Nickel does not form complex with thiocyanate and pass through the minicolumn and then it can be determined by using 4-(2-pyridylazo)-resorcinol (PAR) as chromogenic reagent. So, parameters such as thiocyanate concentration and pH effects on the separation efficiency, sorption capacity of the polyurethane foam minicolumn, influence of the flow rates, PAR concentration, pH effect on the chromogenic reaction, minicolumn regeneration, analytical features and others were investigated. The results demonstrated that nickel (at concentration of 0.5 mg/ml) can be quantitatively separated from iron and copper (200 mg/ml), zinc and cobalt (100 mg/ml) by using a minicolumn containing 0.125 g of polyurethane foam. Nickel can be determined with great selectivity and sensitivity and the procedure was applied for nickel determination in brass, bronze, steel and rock certified reference materials. The results showed satisfactory accuracy and precision. The limit of detection was 77 ng/ml and the RSD was 2.63%. A dynamic range from 0.25 up to 5.00 µg/ml and a sample throughput of 24 samples per hour were achieved.
Nickel Spectrophotometry Solid phase extraction Column Preconcentration Reference material Optimization

"Flow Injection Analysis Of Calcium In Serum, Water And Waste Water By Spectrophotometry And By Ion-selective Electrode"
Anal. Chim. Acta 1978 Volume 100, Issue 1 Pages 151-165
E. H. Hansen, J. Rika and Animesh K. Ghose

Abstract: The flow injection technique is a fast, reliable, and sensitive method for the determination of Ca in various aqueous as well as serum samples; spectrophotometric or potentiometric detection can be used. At sampling rates of 100-10 samples/h, with 30 µL sample injections, high reproducibility of measurement and low reagent consumption are achieved in both methods. In the spectrophotometric method (with o-cresolphthalein complexon), the anal. readout is available within 12 s after sample injection at a total reagent consumption of 0.75 mL/anal. The potentiometric measurement of the Ca activity in serum is placed on a reliable basis by alternating measurements of serum samples and aqueous standards without incurring any nonreproducible changes in potential between aqueous and serum solutions This permits the simultaneous determination of pH and pCa, the anal. readout being available within 3 s of sample injection. The good agreement between the results obtained with the flow injection method and those attained by atomic absorption and EDTA titrns. as well as pCa stat-measurements show that the new methods are potentially suitable for routine anal.
Calcium pH Spectrophotometry Electrode Potentiometry Method comparison

"Determination Of Iron(II) And Iron(III) By Flow Injection And Amperometric Detection With A Glassy Carbon Electrodes"
Anal. Chim. Acta 1980 Volume 114, Issue 1 Pages 267-274
J. W. Dieker and W. E. Van Der Linden

Abstract: Flow injection analysis can be used for the determination of both Fe(II) and Fe(III) with an amperometric detector. The flow-through cell contains a glassy C electrode. Selection of the appropriate voltammetric technique choice of the indication potentials, sample size, composition of the carrier stream, etc., are discussed. The limit of determination is ~10-6M; the calibration curves are linear in the concentration. ranges 10^-3-10-5 M for Fe(III) and 5 x 10^-4-10-5 M for Fe(II). To illustrate the potentialities of the proposed method, standard rocks have been analyzed.
Iron(2+) Iron(III) Amperometry Electrode Speciation Optimization Reference material

"Sequential Injections In Flow Systems As An Alternative To Gradient Exploitation"
Anal. Chim. Acta 1985 Volume 173, Issue 1 Pages 289-297
E. A. G. Zagatto, M. F. Giné, E. A. N. Fernandes, B. F. Reis and F. J. Krug

Abstract: Because zone-sampling from a pronouced concentration. gradient (cf. Reis et al., Anal. Abstr., 1981, 41, 2J20; Gine et al., Ibid., 1984, 46, 7G1) is prone to imprecision due to flow fluctuations, sampling from a zone of virtually constant concentration. resulting from the merging of, e.g., three plugs of the sample solution injected simultaneously at different positions into the carrier stream ('sequential injections') has been investigated. Such a zone corresponds to one of the maxima or minima of the resultant concentration. - time profile, and the concentration. corresponding to this zone can be adjusted by varying the lengths of the mixing coils between the injection positions. An injection manifold is described for the determination of Mn in rocks by sequential-injection zone-sampling - AAS; output corresponding to a wide range of concentration. (e.g., 80 to 6000 µg g-1; up to 20 µg mL-1 injected) can be accomodated on a single recorder chart. A manifold is also described for the zone-sampling introduction of standard additions to the sample solution for the determination of Cu in ethanol by flow injection AAS.
Manganese Copper Spectrophotometry Gradient technique Standard additions calibration Zone sampling

"Determination Of Molybdenum(VI) In Natural Water And Rock By Ion-exchange Absorptiometry Combined With Flow Analysis"
Anal. Chim. Acta 1989 Volume 225, Issue 1 Pages 313-321
Kazuhisa Yoshimura and Shiro Matsuoka, Hirohiko Waki

Abstract: Ion-exchange absorptiometry combined with flow analysis has been applied to the determination of trace amounts of molybdenum(VI) in natural water and rock. By using a pretreatment column packed with Sephadex G-25 gel, molybdenum(VI) in a sample solution can be sorbed selectively on the gel at pH 3.5. The molybdenum(VI) in the column was desorbed with EDTA as the molybdenum(VI)-EDTA complex, and the solution was introduced into a Tiron solution stream. The yellow complex formed between molybdenum(VI) and Tiron in the flow system was then concentrated on a QAE-Sephadex A-25 anion exchanger packed in a flow-through silica micro-cell. The attenuation of incident light by the molybdenum(VI)-Tiron complex on the anion exchanger in the cell was continuously recorded with a spectrophotometer at 410 nm. The complex on the anion exchanger was easily desorbed with sodium nitrate, so the flow-through cell could be used repeatedly. The minimum amount that could be detected corresponded to 15 ng of molybdenum(VI). Molybdenum(VI) in three or four sample solutions could be determined within 1 h.
Molybdenum(VI) Ion exchange Spectrophotometry

"Flow Analysis For Trace Amounts Of Copper By Ion-exchanger Phase Absorptiometry With 4,7-diphenyl-2,9-dimethyl-1,10-phenanthroline Disulfonate And Its Application To The Study Of Karst Groundwater Storm Runoff"
Anal. Chim. Acta 1992 Volume 268, Issue 2 Pages 225-233
Kazuhisa Yoshimura* and Shiro Matsuoka, Youji Inokura, Ushio Hase

Abstract: Water (8.3 mL; containing 0.8 to 80 ng of copper) was introduced into a carrier stream of aqueous 1% (v/v) HCl. Simultaneously, into a second carrier stream comprising 50 g of hydroxylammonium chloride and 200 g of citric acid in 500 mL of water mixed with 10 mL of 4% BL-9EX and adjusted to pH 6 with aqueous NH3 was introduced 2.1 mL of a solution of the cited reagent (50 µg mL-1 in the second carrier stream). The two carrier streams merged and aqueous 10% (v/v) HNO3 was introduced as desorbing agent before passage of the solution through a mixing coil and a flow-through absorptiometric detector containing QAE Sephadex A-25 to concentrate the Cu complex for continuous measurement of absorbance at 484 nm. The system afforded a detection limit of 0.08 ng mL-1 of Cu and selectivity was good. The method was used to monitor the infiltration of storm water from the soil into the underground river of a karst groundwater system. It could also be used to determine Cu in rock samples after microwave digestion with HNO3 and HF. Ion-exchanger phase absorptiometry was applied to flow anal. for trace amounts of Cu in water. The increase in the absorbance of the colored complex with 4,7-diphenyl-2,9-dimethyl-1,10-phenanthroline disulfonate, which was concentrated online on to an ion exchanger packed in a flow-through cell, can be measured continuously with a spectrophotometer at 484 nm. The detection limit was 0.08 ng/mL of sample solution. The proposed method permitted a highly sensitive, selective determination of copper in karst groundwater samples without any pre-concentration. By measuring the Cu concentration. response in water after a storm, the infiltration rate of rain water from the soil zone to the underground river of a karst groundwater system was estimated ~10-20 m/day.
Copper Sample preparation Spectrophotometry Solid phase detection Sephadex

"Application Of Ion-exchanger Phase Visible-light Absorption To Flow-analysis Determination Of Vanadium In Natural-water And Rock"
Anal. Chim. Acta 1995 Volume 317, Issue 1-3 Pages 207-213
Shiro Matsuoka*, Kazuhisa Yoshimura and Akira Tateda

Abstract: Ion-exchanger phase visible light absorptiometry combined with flow analysis has been developed and applied for the determination of vanadium in natural water and rock. The vanadium(IV) and vanadium(V) in the sample solution reacted with xylenol orange (XO) which was immobilized on the AG 1-X2 anion-exchanger packed in flow-through cell, and the increase in light absorption caused by the formation of the vanadium-XO complex in the resin was directly measured with a spectrophotometer at 532 nm. The interference by most of the co-existing ions can be effectively eliminated using trans-1,2-cyclohexanediamine-N,N,N',N'-tetraacetic acid (CyDTA) and ammonium tartrate. The detection limit was 80 ng L-1 with 5.0 cm(3) of sample solution. Vanadium contents in three sample solutions could be determined within 1 hour. (24 references)
Vanadium(IV) Vanadium(V) Ion exchange Spectrophotometry Immobilized reagent Interferences Solid phase detection

"Sequential Determination Of Iron And Titanium By Flow Injection Analysis"
Talanta 1992 Volume 39, Issue 10 Pages 1229-1232
M. G. M. Andrade, S. L. C. Ferreira, B. F. Santos and A. C. S. Costa

Abstract: Rock was dissolved in 98% H2SO4 - 40% HF - 37% HCl and the solution was injected into a carrier stream (3.5 mL-1) of acetate buffer, of pH 6.0; simultaneously 0.5% 3,4-dihydroxybenzoic acid was introduced into the carrier stream. The absorbance of the solution were measured for Ti at 380 nm and for Fe at 380 and 570 nm. The calibration graphs were rectilinear from 2 to 10 and 10 to 40 µg mL-1, respectively. The coefficient of variation were ~2%. The results on geological reference materials were similar to the certified values. A flow injection method has been developed for the sequential spectrophotometric determination of iron and titanium using 3,4-dihydroxybenzoic acid as chromogenic reagent. The system involves the sequential measurement of the absorbances of the complexes at 380 and 570 nm. The system is designed using a simultaneous injection of sample and reagent into sep. carrier streams. The proposed method is characterized by a precision of about 2%, a sampling rate of about 50 samples per h, and a reagent consumption of 200 µL (0.50% of solution) per sample. The method is relatively free of interferences and was used for the sequential determination of titanium and iron in rocks.
Iron Titanium Spectrophotometry Interferences Reference material Chromogenic reagent Reagent consumption

"Flow Injection System With Ion-exchange For Spectrophotometric Determination Of Copper In Rocks"
Talanta 1993 Volume 40, Issue 4 Pages 551-555
Eluzir Moraes Pedrazzi, Ricardo Erthal Santelli

Abstract: Rocks were ground (400 mesh) and digested with HF - HClO4. The Fe(III) was removed, as the hydroxide, by treatment with NH4Cl and 18 M NH3. The Cu was pre-concentrated (~50-fold) by passage at 1.75 mL min-1 through a column (4 cm x 4 mm) of CHELEX-100 (Bio-Rad Labs., 200 to 400 mesh, Na form) followed by elution with 2.5 M HNO3 at 1.75 mL min-1. The color reagent (pH 10 to 11; 0.75 mL min-1) was a mixture of diethanolamine - carbon disulfide - Na2EDTA - aqueous 25% NH3 diluted with water. Beer's law was obeyed from 0.04 to 2.0 µg mL-1 of Cu and the precision for rocks containing 4 to 198 µg g-1 and 0.4 to 1.4 µg g-1 of Cu were 10 and 20%, respectively; an interference study is also presented. Results obtained by this method were in good agreement with certified reference rock sample values.
Copper Sample preparation Spectrophotometry Preconcentration Column Chelex Reference material Interferences

"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

"Determination Of Palladium By Flame Atomic Absorption Spectrometry Combined Online With Flow Injection Preconcentration Using A Micro-column Packed With Activated Carbon Fibre"
Talanta 1995 Volume 42, Issue 7 Pages 921-926
Soulin Lin*, Chunsong Zheng and Guizhen Yun,

Abstract: A flow system (diagrams given) comprising a microcolumn (2.5 cm x 3 mm i.d.) packed with activated carbon fiber was used for the pre-concentration of Pd before determination by flame AAS. A similarly packed second column increased the sensitivity by doubling the analytical signal. The two columns wee in parallel in the pre-concentration mode and connected in series in the elution mode. The best pH value for retention of the metal was 3; dilute HCl was added to adjust the pH. The calibration graph was linear up to 30 ng/ml and the detection limit was 0.3 ng/ml. The RSD (n = 8) was 3.9%. Effects of interferents are tabulated. The method was applied to the determination of Pd in rock samples. Rock (0.1 g) was wetted with water in a PTFE crucible and 10 mL HF was added, heated and evaporated to dryness. Aqua regia (15 ml) was added, with gentle heating and evaporated to near dryness. HCl (2 ml) was added and the volume was made up to 100 mL with water. A portion (1 ml) was analyzed as above.
Palladium Sample preparation Spectrophotometry Preconcentration Column Carbon fiber Interferences Activated carbon

"Flow Injection Analysis Of Environmental Samples For Nitrate Using An Ion Selective Electrode"
Analyst 1977 Volume 102, Issue 1219 Pages 705-713
E. H. Hansen, Animesh K. Ghose and J. Ruzicka

Abstract: NO3- in soil extracts, wastewater, and fertilizer solutions was determined by addition of a pH 9.5 buffer of 10^-2 M Na tetraborate + 10^-2 M NaOH and measuring the peak max. value in a flow injection system with a NO3--selective electrode. Aqueous extracts of particulate NO3- in air were analyzed without pretreatment. The electrode consisted of tetraoctylammonium bromide in di-Bu phthalate and was calibrated at 10^-5 - 10^-2 M NO3-. For injection of 0.3 mL samples the anal. rate was 90 samples/h. The standard deviation was typically 0.2-0.5 mV, equivalent to 1-2%. The electrode lifetime was 2-3 months. A method is proposed for identifying and correcting for the presence of interferents by observing the shape of each peak and determining its negative elevation. Based on the flow injection principle and employing a nitrate electrode situated in a flow-through cell, a simple, reliable and sensitive method for the automated determination of nitrate and its use for analyzing soil extracts, waste waters, fertiliser solutions and air samples are described. At a sampling rate of 90 samples per hour a standard deviation of only 1-2% is typical. A new approach to identifying and correcting for the presence of interfering species in potentiometric measurements is discussed.
Nitrate Electrode Apparatus Interferences

"Determination Of Nitrogenous Gases Evolved From Soils On Closed Systems"
Analyst 1979 Volume 104, Issue 1239 Pages 538-544
C. J. Smith and P. M. Chalk

Abstract: A simple method is described for determining nitrogen oxide and nitrogen dioxide, evolved from soils, in closed systems. These gases are absorbed by an acidic solution of potassium permanganate, and the resulting nitrate is determined by a steam distillation method. Excess of permanganate is reduced with iron(II) sulphate and neutralized with sodium hydroxide solution. Ammonium in solution is removed by distillation with magnesium oxide, and nitrate is determined by distillation after reduction to ammonium by Devarda's alloy.Nitrogen and dinitrogen oxide evolved from soils are measured using gas chromatography on a single 0.61 m column of molecular sieve 5A, temperature programmed to 250°C at 39°C min-1, after an initial period of 1 min at 35°C. A complete analysis requires 19.5 min, and 2 µg of nitrogen can be determined quantitatively for each gas.
Nitrate Nitrogen Nitrogen monoxide Nitrogen dioxide GC Conductometry Conductometry Closed loop

"Flow Injection Sample-to-standard Additions Method. Spectrophotometric Determination Of Hydrochloric Acid And Orthophosphate"
Analyst 1989 Volume 114, Issue 7 Pages 843-848
Yecheskel Israel and Ramon M. Barnes

Abstract: An equation is proposed that allows calculation of sample concentration. from two transient signals obtained from injection of sample and blank solution of matrix-matched composition. The equation was applied in the sample-to-standard additions determination of (i) HCl and (ii) phosphate in rock digests. For (i), a two-channel manifold was used with HCl as carrier (2 mL min-1), 0.2 M Na acetate - 50 mg L-1 bromocresol green - 0.002% of Triton X-100 as reagent (2.8 mL min-1) and detection at 444 nm. In general, the coefficient of variation was 1%. For (ii), a three-channel manifold was used, standard rock digests solution were used for sample and carrier (1.2 mL min-1), the reagent solution (prep. described) was molybdovanadate in dilute HNO3 (1.5 mL min-1), the diluent solution (1.2 mL min-1) was water or dilute HNO3 and detection was carried out between 410 and 450 nm. The coefficient of variation was 1%. In both instances, an autosampler was used to provide a sample throughput of 80 to 100 h-1.
Hydrogen chloride Phosphate Sample preparation Spectrophotometry Signal processing Triton X Standard additions calibration Surfactant

"Spectrophotometric Flow Injection Determination Of Titanium In Rocks"
Analyst 1992 Volume 117, Issue 9 Pages 1519-1521
Ricardo Erthal Santelli and Rita de Cássia dos Santos Araujo

Abstract: Finely ground rock (0.1 g) was fused with 1 g of a stoicheiometric mixture of H3BO3 and LiCO3 at 950°C for 25 min in a Pt crucible. After cooling, the residue was dissolved in 50 mL of 4% HNO3 and diluted to 100 mL with water. The 10% hydroxylamine hydrochloride masking solution and chromotropic acid - acetate buffer were mixed and directed towards the sample carrier stream. Sample (75 µL) was introduced into the carrier stream, the color developed and the absorbance was measured at 465 nm. Standard rock samples from the US Geological Survey and Geological Survey of Japan were used to assess the accuracy of the method. With a solution sampling frequency of 80 h-1, coefficient of variation were 0.6% allowing for the determination of 0.1 to 3.0% TiO2. The flow injection manifold system (schematic diagram given) was stable for 4 hours, with low reagent consumption (~6 mg per sample) and a detection limit of 0.05 µg mL-1. A flow injection system for the spectrophotometric determination of titanium in rocks using chromotropic acid as the color-forming reagent is described. Sample decomposition involving the use of metaborate was investigated. In addition, the optimization of chemical and phys. variables and a study of interfering ions was also carried out. Standard rock samples from the United States Geological Survey and Geological Survey of Japan were used to assess the accuracy of the method. With a solution sampling frequency of 80 h-1, the system yields precise results (relative standard deviation <0.6%), making the determination of 0.1-3.0% TiO2 in rock samples possible. The proposed system is stable for at least 4 h, has low reagent consumption (about 6 mg per sample) and a detection limit of 0.05 µg mL-1.
Titanium Sample preparation Spectrophotometry Reference material Optimization Interferences Reagent consumption

"Trial Measurements In Flow Analysis"
Analyst 1993 Volume 118, Issue 6 Pages 719-722
Boaventura Freire dos Reis, Elias Ayres Guidetti Zagatto, Patricia Benedini Martelli and Sandra Maria Boscolo Brienza

Abstract: In flow analysis trial measurements can be obtained by sequential injection or gradient exploitation. The potential and limitations of both strategies were evaluated. Both methods were applied to the determination of Mn in rocks by AAS. Different set ups were designed with the main reactor of the flow systems being connected to the aspiration tubing of the spectrometer. For trial measurements with sequential injections, peak maxima were quantified following an increasing concentration. sequence and measurements were compared with a threshold value which was selected as an absorbance of 0.3. The system was set-up to provide three overlapping peaks with heights in a ratio of approximately 10:3:1. In gradient exploitation the peaks were also quantified so that no modifications to the detector were needed. The results were in agreement with those obtained by ICP-AES.
Manganese Spectrophotometry Method comparison Gradient technique

"Flow Injection Spectrophotometric Determination Of Uranium With In-valve Ion-exchange Column Preconcentration And Separation"
Analyst 1995 Volume 120, Issue 8 Pages 2107-2110
Kate Grudpan, Saisunee Laiwraungrath and Ponlayuth Sooksamiti

Abstract: The sample solution was passed (1-4 ml/min) through a column (6 cm x 3.2 mm i.d.) of Duolite C-225(H) resin (pre-treated with 6 M HCl) positioned in the injection valve of the flow injection manifold. The column was washed with water and elution of U was effected by passing 1 M HCl (4 ml/min) through the column. The column eluate flowing from the injection valve was merged with a stream (8 ml/min) of 1 M triethanolamine buffer of pH 8 containing 0.7% 1,2-cyclohexanediaminetetraacetic acid and with a reagent stream (8 ml/min) of 0.02% 4-(2-pyridylazo)resorcinol in 0.1 M NaOH. The merged streams were passed through a glass bead column (10 cm x 3.2 mm i.d.) and the absorbance of the colored solution was measured at 530 nm. A diagram of the manifold used is given. The calibration graph was linear up to 7 µg of U, the detection limit was 0.27 µg and the RSD (n = 12) for 2 µg of U was 2.1%. By using dual ion-exchange columns in the injection valve, a throughput of 20-25 samples/h was achieved. The method was applied to the analysis of U in rocks and water.
Uranium Ion exchange Spectrophotometry Resin Glass beads Column Matrix removal Preconcentration

"Flow Injection Calibration Of Inductively Coupled Plasma Atomic Emission Spectrometry Using The Generalized Standard Additions Method"
J. Anal. At. Spectrom. 1988 Volume 3, Issue 5 Pages 673-678
Maria Fernanda Gin&eacute;, Francisco Jos&eacute; Krug, Henrique Bergamin Filho, Boaventura Freire dos Reis, Elias Ayres Guidetti Zagatto and Roy Edward Bruns

Abstract: The generalized standard-additions method, employing least squares regression, was applied to obtain the calibration matrix for multi-element analysis by ICP-AES. The method is based on response variations following known additions of interfering and test elements. As a number of additions are required, a flow injection system that permits high sampling rates and low consumption of sample is used. The zone sampling approach is applied as it allows selection of regions with different mean concentration. The flow injection apparatus is coupled to an ICP-AES instrument, the operating parameters of which are adjusted to minimize inter-element effects. The method was applied in the analysis of rock reference materials and results agreed well with certified values. The reproducibility of the calibration matrix was >99.5%.
Trace elements Spectrophotometry Interferences Reference material Standard additions calibration Zone sampling

"Analysis Of Geological Materials For Bismuth, Antimony, Selenium And Tellurium By Continuous-flow Hydride-generation Inductively Coupled Plasma Mass Spectrometry. 2. Methodology And Results"
J. Anal. At. Spectrom. 1997 Volume 12, Issue 1 Pages 103-106

Abstract: The apparatus and procedure for removal of mutual interference were as described in Part 1 (Ibid., 1997, 12, 97). Sample digestion with aqua regia gave complete recovery of Bi, but some matrices required digestion with HF/HClO4/HNO3/HCl to obtain full recoveries of Te, Se and Sb. The analytes were separated from some potentially interfering elements (e.g., Co, Cu and Ni) by coprecipitation on lanthanum hydroxide. Results are presented for 18 of the Chinese GSD and GSR stream sediment and rock standard reference materials. RSD were in the range 3-8% and the detection limits were 1 µg/kg for Bi and Te and 6 µg/kg for Sb and Se.
Antimony Bismuth Selenium Tellurium Sample preparation Mass spectrometry Detection limit Coprecipitation Interferences Reference material

"Semiautomated Method For The Determination Of Selenium In Geological Materials Using A Flow Injection Analysis Technique"
Anal. Chem. 1985 Volume 57, Issue 7 Pages 1482-1485
Chris C. Y. Chan

Abstract: A non-segmented stream is used instead of an air-segmented stream in a continuous-flow system in series with hydride generation and AAS A flow injection module is used for insertion of the sample segment into the stream, and, as air bubbles are not required for mixing and segmenting the solution, narrow tubing can be used throughout. This allows more rapid transport of the sample, the sample zone is better defined and not diluted by the carrier solution, the volumes of sample segments are very reproducible and the sample and reagent solution can be well mixed within a narrow stream, so that the signal response is more rapid and precise with improved peak shape and height. Results from the analysis of 40 reference samples gave coefficient of variation of 15% with a mean of 2.85% (n = 3 to 10). The limit of determination was 5 ppm of Se.
Selenium Spectrophotometry Reference material Peak shape

"Computerized Flow Injection Potentiometric Stripping Analysis With Large-volume Wall-jet Cell"
Fresenius J. Anal. Chem. 1988 Volume 332, Issue 2 Pages 148-152
Wojciech Matuszewski, Marek Trojanowicz and Wolfgang Frenzel

Abstract: A flow injection system is described incorporating a large-volume wall-jet cell (diagram given) and a microcomputer for digital signal recording and data processing. The working electrode was a vitreous-carbon rod of 3 mm diameter pressed into PTFE. A SCE was used as reference electrode and platinum foil (1 cm2) was used as auxiliary electrode. The electrodes were immersed in 0.1 M HCl (carrier solution). The system was applied in the simultaneous determination of Cd and Pb in geological materials. Rock or ore (100 mg) was mixed with 5 mL of 40% HF and heated to dryness in a sand bath at 400°C. The residue was dissolved in 5 mL of 4% H3BO3 and the solution was diluted to 10 mL (rocks) or 50 mL (ore) with 0.1 M HCl. A 750 µL portion of solution was injected; the deposition time was 8 min at -1.15 V vs a SCE; the flow rate was 1.5 mL min-1. Potentiometric stripping was carried out under stopped-flow conditions by using 40 ppm of Hg(II) in 0.1 M HCl as oxidizing agent. Results agreed with those by AAS.
Cadmium Lead Potentiometric stripping analysis Electrode Electrode Computer Method comparison Stopped-flow

"Determination Of Bismuth In Geological Materials By Flow Injection Hydride Generation Atomic Absorption Spectrometry"
Anal. Lett. 1990 Volume 23, Issue 12 Pages 2259-2272
Chan, C.C.Y.;Baig, M.W.A.;Lichti, P.A.

Abstract: Powdered rock (0.2 g) was digested with HF - HClO4 - HNO3. The evolved hydride was carried through to the heated quartz tube by a stream of Ar and Bi was determined by AAS. Thiosemicarbzide and 1,10-phenanthroline were used as masking agents to control interference from Cu and Ni. Determination levels were 10 ppb and sample throughput was 50 hr-1. Results are compared with the conventional AA method. Results are reported for 13 international geological reference samples.
Bismuth Sample preparation Spectrophotometry Interferences Reference material Method comparison

"High Performance Ion-chromatographic Separation Of Uranium And Thorium In Natural Waters And Geological Materials"
J. Chromatogr. A 1992 Volume 602, Issue 1-2 Pages 119-125
Michael P. Harrold*, Archava Siriraks and John Riviello

Abstract: Digested rock samples and water were analyzed on a column (25 cm x 4 mm) of Ion Pac CS-2 with a linear gradient of 0.6 M HCl to 0.6 M HCl - 0.5 M Na2SO4 at 1.0 mL min-1. Detection was by post-column derivatization with 0.3 mM arsenzo III in 0.5 M acetic acid containing 0.1% Triton X-100 at 0.5 mL min-1 and measurement at 660 nm. With samples containing 50 µg L-1 or with a high ionic strength, pre-concentration. was carried out on a column of MetPac CC-1 at pH 5.5, followed by elution with 20 M ammonium acetate. The results on reference rock and seawater standards were close to certified values.
Uranium Thorium-232 HPIC Sample preparation Spectrophotometry Post-column derivatization Reference material Metpac Triton X Surfactant

"Online Sorption Preconcentration And Inductively Coupled Plasma Atomic Emission Spectrometry Determination Of Rare-earth Elements"
Spectrochim. Acta B 1996 Volume 51, Issue 11 Pages 1417-1423
O. N. Grebnevaa, Corresponding Author Contact Information, N. M. Kuz'mina, G. I. Tsysinb and Yu. A. Zolotov

Abstract: The system for online microcolumn sorption pre-concentration and inductively coupled plasma atomic emission spectrometry determination of 14 rare earth elements (REEs) is described. Aminocarboxylic sorbents of different structure are used. Preconcentration of REEs from the 20 mL of sample solution and elution with 210 µl of 1 mol L-1 HCl results in an enrichment factor of 99. The detection limit of REEs is about nx 0.1 µg L-1 (RSD 3-5%). The possibility of simultaneous REE determination in complicated solutions is demonstrated.
Metals, rare earth Spectrophotometry Sample preparation Resin Preconcentration Column Solid phase extraction

"Analysis Of Difficult Samples By Flow Injection Inductively Coupled Plasma Mass Spectrometry"
Anal. Proc. 1992 Volume 29, Issue 7 Pages 274-275
Andreas Stroh and U. V&ouml;llkopf

Abstract: The use of flow injection analysis in ICP-MS results in very short exposure of a strong matrix to the interface region, thus no build-up of matrix deposition on sampler or skimmer cone occurs. The system was applied to multi-element analysis with a small sample volume (0.5 ml) and use of an acid carrier stream. Results are tabulated for 1 and 3% NaCl solution; recoveries were 83 to 117% and coefficient of variation were 0.4 to 4.3%. It was not necessary to dilute samples. The system was also applied to the analysis of a standard reference rock material; results were in close agreement with certified values. FIA also permits automatic online matrix separation or pre-concentration techniques to be implemented into routine ICP-MS applications.
Mass spectrometry Reference material Preconcentration Matrix removal

"Online Concentration And Flow Analysis Of Trace Amounts Of Bismuth With Anion-exchange Method And Ion-exchanger Absorptiometry"
Bunseki Kagaku 1987 Volume 36, Issue 11 Pages 656-661
Yoshimura, K.

Abstract: Bismuth (0.012 to 0.5 nmol) in various samples (e.g., 1 l of water) was pre-concentrated as a chloro-complex from 0.1 to 0.6 M Cl- by using a Dowex 1-X8 anion-exchange column (Cl- form; 100 to 200 mesh). Bismuth was desorbed with 0.15 M H2SO4 at a flow rate of 1.2 mL min-1 and mixed with a solution containing 1 M KI at 0.3 mL min-1. After introduction into the flow-through cell, the light path portion of which was filled with QAE Sephadex A-25 anion exchanger, the light attenuation due to the iodo-complexes of Bi (concentrated on the anion exchanger in the cell) was measured directly at 472 nm, with high precision. The calibration graph for Bi was rectilinear and the method was applied to samples of rocks and metals.
Bismuth Ion exchange Spectrophotometry Preconcentration Dowex Resin Sephadex Solid phase detection

"Flow Injection Analysis For Trace Amounts Of Silicon On Spectrophotometric Determination Of Molybdosilicic Acid"
Bunseki Kagaku 1988 Volume 37, Issue 10 Pages T115-T119
Motomizu, S.;Korechika, K.

Abstract: Sample solution (320 µL) was injected into a carrier stream (0.7 mL min-1) of water, which was mixed with reagent solution (0.7 mL min-1), containing 6 mM Mo(VI) and 75 mM H2SO4, in a 9-m coil in air at 100°C. The reaction mixture passed through a cooling coil (1 m x 0.5 mm) in a water bath at 20°C, and molybdosilicic acid was measured by its absorbance at 350 nm. The calibration graph was rectilinear for 10 to 1000 ppb of Si. The detection limit was 2 ppb. In determination of 10 and 60 ppb of Si, coefficient of variation (n = 6) were 4 and 0.5%, respectively. Thirty samples could be analyzed in 1 h.
Silicon Spectrophotometry Calibration Heated reaction

"Flow Injection Analysis Spectrophotometric Determination Of Scandium In Rocks With A New Chromogenic Reagent Chlorophosphonazo-pB"
Fenxi Ceshi Tongbao 1990 Volume 9, Issue 5 Pages 78-81
Qiu Ruolan;Xiao Jinrong;Chen Daren;He Ling;Wu Bincai

Abstract: A new color reaction of Sc with chlorophosphonago-pB (CPA-pB) has been studied. By normal operation of spectrophotometry, the molar absorptivity is 7.0 x 10^-4 L mol-1 cm-1, and Beer's law is obeyed in the range of 7-18 µg Sc2O3/25 ml at 740 nm. By flow injection analysis spectrophotometric method associated with micro-computer, the Linear range is expanded to 5-45 µg Sc2O3/25 ml. The FIA is rapid, automatic, good accuracy and high repeatability, This method can be used to determine the Sc in the rock.
Scandium Spectrophotometry Chromogenic reagent Computer

"Simple Single-channel Flow Injection Spectrophotometer"
Fenxi Huaxue 1985 Volume 13, Issue 7 Pages 545-548
Lu, Y.;Zhu, Y.;Yan, Z.

Abstract: A single-channel flow injection spectrophotometer comprising a Mariotte vessel (as reagent reservoir and to provide pressure for reagent flow), a rotary sampling valve, a PVC thin tube and a µflow-through cell is described. It has been applied in determination of Ti and Fe in standard rocks; results agreed with certified values. The coefficient of variation was <4%.
Titanium Iron Spectrophotometry Detector General Reference material

"Determination Of Arsenic, Antimony And Bismuth By Inductively Coupled Plasma Atomic-emission Spectrometry With Flow Injection Analysis And Hydride Generation"
Fenxi Huaxue 1991 Volume 19, Issue 11 Pages 1285-1287
Gao, H.;Li, K.

Abstract: A 0.175-g ore or rock sample was wetted with a little water and then dissolved in 9 mL of HCl plus 3 mL of HNO3 and 1 mL of H2SO4 (1:1); after evaporation to fumes and cooling, 2.5 mL of HCl, 5 mL of 10% KI - 5% ascorbic acid - 5% thiourea solution and water were added to 25 mL. The solution was then carried at a flow-rate of 11 mL min-1 to react with 1% KBH4 solution (containing 0.2% of NaOH) at 5.5 mL min-1 in the flow injection system (diagram pesented), and the generated hydrides were carried by Ar (0.6 l min-1) for separation by a gas separator before passing to a direct-reading spectrometer for ICP-AES determination of As, Sb and Bi with measurement at 193.76, 217.5 and 306.7 nm, respectively. By the standard-additions method, recoveries were 94 to 107%. Determination ranges for As, Sb and Bi were up to 1000, 300 and 300 µg g-1, respectively, and their corresponding detection limits were 0.2, 0.2 and 0.1 µg g-1. Masking agents could be used to increase tolerance levels of the co-existing ions; background interferences in the gas phase could be corrected for.
Antimony Arsenic Bismuth Spectrophotometry Interferences Standard additions calibration

"Application Of Flow Injection Analysis In Rock And Mineral Analysis"
Fenxi Shiyanshi 1988 Volume 7, Issue 2 Pages 37-44
Dan Dezhong

Abstract: The flow injection analysis (FIA) is a new wet chemical method for rapid and automatic analysis. The review summarized systematically the application of FIA in rock and mineral analysis, discussed the various functions and usages of the technique. The trend of FIA in rock and mineral analysis was pointed out. Forty six references were included.

"Simultaneous Determination Of Aluminum And Iron By Flow Injection Dual-chromogenic Agent And Dual-wavelength Spectrophotometry"
Fenxi Shiyanshi 1994 Volume 13, Issue 1 Pages 26-28
Zhao, Z.Y.;Han, Q.F.;Xie, J.;Zhang, Q.H.;Wang, Y.F.;Zhao, Q.;He, Y.L.

Abstract: The method proposed for simultaneous determination of Al and Fe is based on the formation of the colored complexes Al(III)-chromazurol A (I) and Fe(II)-nitroso R salt (II). Standard solution containing 5 µg/ml of Al and 25 µg/ml of Fe was mixed with 2 drops of 10% ascorbic acid, the solution was adjusted to pH 5.6 with aqueous 50% NH3 and dilute HCl and diluted to 20 mL with water. The solution was mixed with acetic acid/sodium acetate buffer solution of pH 5.6 and diluted to 25 mL with water. A 37 µL portion of the solution was injected into a carrier stream (2 ml/min) of water, followed by mixing a stream (2 ml/min) of mixed reagent of 0.048% each of I and II in the buffer solution The absorbance differences were measured at 600 and 841.5 nm for determination of Al and at 710 and 841.5 nm for Fe. The calibration graphs of Al and Fe were linear for up to 2 µg/ml of Al and 8 µg/ml of Fe; the RSD (n = 11) were 0.9% and 1.1%, respectively. Recoveries were 96-103% for Al and 94-98.8% for Fe. Tolerance levels are given for 13 co-existing ions. The method was used to determine Al and Fe in rocks.
Aluminum Iron Spectrophotometry

"Analysis Of Rocks And Minerals"
Fenxi Shiyanshi 1996 Volume 15, Issue 4 Pages 100-110
Tang, Z.Y.;Jin, Z.X.

Abstract: A review is presented, covering literature of Chinese origin published between July 1993 and June 1995, which includes sample pretreatment and pre-concentration, gravimetry, titrimetry, spectrophotometry, atomic spectrometry, electrochemical analysis, X-ray fluorescence spectrometry, chromatography, flow injection analysis, chemical phase analysis as well as standard reference materials and quality control. (445 references).
Spectrophotometry Review Reference material Preconcentration

"Analysis Of Rocks And Minerals"
Fenxi Shiyanshi 1998 Volume 17, Issue 4 Pages 97-109
Sun, S.;Sun, L.

Abstract: This is the sixth biennial review on anal. of rocks and minerals in 'Fenxi Shiyanshi'. The review, with 481 references, covers the aspects of development in the analysis of rocks and minerals in China from July 1995 to June 1997. It contains following subtitles: introduction, Sample pretreatment, gravimetry and titrimetry, spectrophotometry, atomic emission spectrometry, atomic absorption spectrophotometry and atomic fluorescence spectrometry, electrochemical analysis, X-ray fluorescence spectrometry and electron microbeam analysis, chromatography and activation methods, flow injection analysis, chemical phase analysis, reference material and standard methods.

"Autocatalysis In The Spectrophotometric Flow Injection Determination Of Manganese As Permanganate. Soil, Plant And Rock Analysis"
J. Braz. Chem. Soc. 1990 Volume 1, Issue 1 Pages 28-34
M. Mesquita, A O Jacintho, E. A G. Zagatto and R. F. Antonio

Abstract: Periodate oxidation was carried out under acidic conditions at ~95°C. The reaction rate was accelerated by exploiting the autocatalytic effect which was enhanced with addition of a permanganate confluent stream. Reagent concentration, permanganate addition, level, acidity, flow rates, color stability and interference effects were studied. Hydrochloric acid was tolerated up to 0.5M. Detection limit was ~0.3 mg L-1 Mn. Analysis time was 60 h-1. Results agreed well with those obtained by AES.
Manganese Permanganate Spectrophotometry Catalysis Interferences Detection limit Method comparison Heated reaction

"Automated Colorimetric Method For Determination Of Chlorine In Geological Materials Using Flow Injection Analysis Technique"
Lab. Rob. Autom. 1990 Volume 2, Issue 2 Pages 83-88
Chan, C.C.Y.

Abstract: Powdered rock sample (0.15 g) was fused with LiBO2 at 860°C and the melt was dissolved in 9% HNO3. After dilution to 15 ml, the solution was mixed with 0.5% Hg(SCN)2 and 0.5 M Fe(NO3) in a carrier flow of 6% HNO3 and the absorbance was measured at 480 nm. The method was applied to 22 geochemical reference samples and gave coefficient of variation from 0.7 to 9.3%; the results agreed closely with those obtained in the literature. The limit of determination was 15 ppm in rock and calibration covered 50 to 500 ppm.
Chlorine Sample preparation Spectrophotometry Automation Dilution Reference material Detection limit Calibration

"Continuous Determination Of Iron And Titanium In Geological Samples By Alternating Injection Spectrophotometry"
Lihua Jianyan, Huaxue Fence 1992 Volume 28, Issue 6 Pages 325-327
Fu, L.;Ren, Y.

Abstract: Rock (0.1 to 0.2 g) was decomposed with water, aqueous 50% H2SO4 and HF and the residue was fused with 1 g of K2S2O7 on a gas lamp. The cooled residue was extracted with 3.6% H2SO4 and the extract was diluted with water to 50 mL. Two portions of solution, one of which was mixed with 0.25 mL of aqueous 2.5% ascorbic acid, were diluted with water to 25 mL. A 160 µL-portion of the pre-treated and masked solution was injected into the flow injection analyzer. (illustrated) to react with 0.1 M Tiron in 10 mM acetate buffer solution of pH 4.6 in a reaction tube (50 cm x 0.5 mm) before detection of Ti at 410 nm. For the detection of Fe, a portion (200 µL) of the untreated solution was similarly injected into the system, detection was at 560 nm. Beer's law was obeyed for 0 to 800 µg of Fe and 0 to 200 µg of Ti in 25 mL of solution The coefficient of variation for Fe and Ti were 0.69 to 3.04 and 0.54 to 10.37%, respectively. Only NbV and Ba2+ interfered. Sampling rate was 80 runs h-1.
Iron Titanium Sample preparation Spectrophotometry Interferences Tiron

"Advances In Analytical Methods Based On Atomic Absorption Spectrometry In The Geochemistry Laboratories Of The Geological Survey Of Canada"
Pap. Geol. Surv. Can. 1987 Volume 87, Issue 1a Pages 477-484
Hall, G E M; De Silva, K N; Pelchat, J C; Vaive, J E

Abstract: Three aspects are considered, viz, (i) development of a method to determine Tl, Ga and In by graphite-furnace AAS at or below their natural crustal abundance in rocks, (ii) determination of Ag, Au, Pd, Pt and Rh in biogeochemical samples and their ash at 2 to 10 ppb level, and (iii) more generally, the improvement of productivity and decrease of reagent consumption by the introduction of flow injection systems of sample preparation, introduction and manipulation.
Thallium Gallium Indium Silver Gold Palladium Platinum Rhodium Spectrophotometry Reagent consumption Sample pretreatment

"Application And Prospects Of Flow Injection Analysis Of Rocks And Minerals"
Yankuang Ceshi 1987 Volume 6, Issue 2 Pages 151-154
Lu, Y.;Zhonghua, P.

Abstract: A review is presented, with 34 references.

"Application And Prospect Of FIA In Rock And Mineral Analysis In China"
Yankuang Ceshi 1992 Volume 11, Issue 1-2 Pages 116-120
Dan, D.Z.

Abstract: A review is presented, with 50 references.

"Present Situation And Perspective Of The Application Of Flow Injection Analysis To Rock And Mineral Analysis"
Yankuang Ceshi 1992 Volume 11, Issue 1-2 Pages 109-115
Lin, S.L.

Abstract: A review is presented, with 56 references. Current situation, potentiality, relevant problems and prospects of flow injection analysis are discussed.

"New Progress In Application Of Flow Injection Analysis In Rock And Mineral Analysis"
Yankuang Ceshi 1993 Volume 12, Issue 2 Pages 142-151
Ma, H.C.;Li, J.X.

Abstract: A review is presented, covering the literature from 1986-1991, with particular emphasis on the simultaneous determination of multiple elements. (77 references).
Review Multidetection

"Flow Injection Catalytic Photometric Determination Of Trace Iodine In Rock And Ore Samples"
Yanshi Kuangwuxue Zazhi 1983 Volume 2, Issue 4 Pages 314-315
Li Kaiyuan, Hua Ping

Abstract: Trace iodine in rock and ore samples was determined by a photometric method based on the reaction 2Ce4+ + As3+ (orange-red) -> 2Ce3+ + As6+ (colorless) catalyzed by ions. The reaction was carried out in a flow injection analyzer with a detection limit of 8 ppb. Thus, a rock sample 0.5 g was added to 1N H2SO4, heated in a boiling water bath for 30 min with vigorous shaking, an aluminum potassium sulfate solution (7 g/100 mL H2O) 1 mL added, and diluted to 10 mL with 1N H2SO4. A 63 mL portion of the sample solution was analyzed in a flow injection analyzer containing sodium arsenite and Ce(SO4)2 solutions at 37°C and 420 nm. Iodine was determined in an apatite sample to be 0.0030%.
Iodine Spectrophotometry Catalysis Heated reaction

"Spectrophotometric Determination Of Aluminum By Flow Injection Analysis"
Yejin Fenxi 1990 Volume 10, Issue 6 Pages 21-23
Shuai, Qin; Lin, Shoulin (SFS)

Abstract: A method for the spectrophotometric determination of aluminum in silicate rocks by flow injection method has been studied in details. Chrome Azurol S was used as the coloring reagent. The dynamic linear concentration. range was 0-10 ppm of Al; the relative standard deviation of the determination was 0.45%; the anal. rate of the flow system of 200 samples/h was achieved.
Aluminum Spectrophotometry