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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Commercial product

Classification: Commercial product -> cement

Citations 6

"Direct FIA - AS Determination Of Potassium And Magnesium In Cement Samples By Use Of The Slurries Approach"
Talanta 1993 Volume 40, Issue 1 Pages 107-112
R. Martinez-Avila, V. Carbonell, A. Salvador and M. de la Guardia

Abstract: Cement (50 mg) was dispersed in 0.13 M HNO3 and 100 µL of this slurry was injected into a double channel flow injection analysis manifold simultaneously with 100 µL of a 10% La buffer solution (prepared from LaCl3.7H2O). This allowed the rapid leaching of K and Mg; if only K was to be determined, the slurry was dispersed in water without acid. The manifold included a well-stirred mixing chamber which provided adequate online dilution prior to flame emission or absorbance measurements. The carrier flow rate was 8.4 mL min-1, which allowed a sample throughput of 48 h-1. The dynamic range of the method was up to 30 or 20 µg mL-1 for Mg and K, respectively. The detection limits were 0.15 mg L-1 for K and 0.29 mg L-1 for Mg, corresponding to 0.007% of K2O and 0.01% of MgO in the slurry. For a sample containing 0.54% of K2O and 1.72% of MgO, the coefficient of variation was about 1% (n = 10). The results agreed with those obtained by flame AAS after alkaline fusion, and had better precision.
Potassium Magnesium Spectrophotometry Spectrophotometry Dilution Slurry Method comparison Well stirred mixing chamber

"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

"Flow Injection Flame Atomic Absorption Analysis Of Iron And Manganese In Cement Samples"
Fresenius J. Anal. Chem. 1993 Volume 347, Issue 8-9 Pages 356-360
A. Salvador, R. Martinez-Avila, V. Carbonell and M. de la Guardia

Abstract: Cement (50 mg) was ultrasonically dispersed in 25 mL of 0.12 M HCl/0.15 M HNO3 and the resulting suspension was digested for 10 min at 50°C. In the determination of Fe, a 100 µL portion of the suspension was injected into a water carrier stream (4 ml/min) and this was passed into a magnetically-stirred mixing chamber (1 mL capacity) before aspiration into an air-acetylene flame for determination by AAS at 248.7 nm. The analytical range was 1-125 µg/ml of Fe. For Mn, a 200 µL portion was injected into a water carrier stream (4 ml/min) and this was passed through a PTFE mixing coil (55 cm x 0.8 mm i.d.) before introducing it into an air-acetylene flame for AAS at 279.5 nm. The analytical range was 0.03-6 µg/ml of Mn. Results for a standard cement and four actual cement samples agreed with certificate values or those obtained by independent analytical procedures.
Iron Manganese Sample preparation Spectrophotometry Reference material Method comparison Well stirred mixing chamber

"Flow Injection Flame Atomic Absorption Spectrometry For Slurry Atomization: Determination Of Manganese, Lead, Zinc, Calcium, Magnesium, Iron, Sodium And Potassium In Cements"
Fresenius J. Anal. Chem. 1994 Volume 350, Issue 6 Pages 359-364
M. A. Bautista, C. Pérez Sirvent, I. López García and M. Hernández Córdoba

Abstract: Cements of varying silica content (details given) were made in to a slurry in the 0.05-0.25% (m/v) range, by weighing appropriate amounts and adding 50 mL of a 30% glycerol/2% HNO3/2% HF solution. The suspensions were submitted to ultrasound for 10 min and stirred for a further 50 min. Portions (50-200 µL) were taken for analysis, while the suspension was being stirred, and fed straight into one of the two flow injection manifolds, (i) for direct injection and (ii) for on line dilution of the slurries (details given). The carrier was water (5 ml/min). For those instances where the online device was used, 0.1% suspensions were prepared in a similar way, but the suspension medium also contained 0.5 g solid lanthanum nitrate. The carrier was 5% glycerol and 1% lanthanum nitrate solution (4 ml/min). Calibration was performed using aqueous standard solutions under the same experimental conditions. Results are tabulated and agreed with those obtained by conventional procedures.
Manganese Lead Zinc Calcium Magnesium Iron Sodium Potassium Sample preparation Spectrophotometry Slurry Suspension Method comparison

"Inductively Coupled Plasma - Atomic-emission Spectroscopy With Flow Injection Analysis"
Spectrochim. Acta B 1983 Volume 38, Issue 1-2 Pages 93-105
Stanley Greenfield

Abstract: Flow injection analysis is applied for solution introduction into an inductively coupled plasma discharge. Properties and advantages of transient emission signals, the analysis of Portland cement, and application of signal integration and multielement FIA-ICP are described. The possibilities of FIA-ICP for 'instant' signal-to-background measurement, calibration by standard additions and exponential dilution, and separation methods are evaluated.
Calcium Spectrophotometry Multielement Review

"Reduction Of Interference Effects In Flame Atomic Absorption Spectrometry Using Flow Injection Techniques"
Anal. Proc. 1989 Volume 26, Issue 2 Pages 58-61
C. E. Adeeyinwo, J. F. Tyson

Abstract: The determination of Ca in the presence of Al was achieved by precipitation of Ca oxalate in a specially designed manifold (details given). The sample was injected into a carrier stream of H20 that was mixed with the reagent stream, viz, aqueous 0.05 M NH3 containing 50 mg L-1 of ammonium oxalate monohydrate; after 5 min a stream of 5% HCl was used to dissolve the ppt. Calcium was determined by AAS at 422.7 nm in an air - acetylene flame. The detection limit was 0.25 mg L-1 of Ca, which is comparable with that of conventional nebulization. The method was applied in the analysis of cement and water.
Calcium Spectrophotometry Precipitation Filter Manifold comparison Interferences