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
Email: schalk@unf.edu
Website: @unf

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NIES 2

Classification: Reference Material -> NIES -> 2 -> Pond sediment

Citations 5

"Determination Of Phosphorus In Turbid Waters Using Alkaline Potassium Peroxodisulphate Digestion"
Anal. Chim. Acta 1995 Volume 315, Issue 1-2 Pages 123-135
L. Woo and W. Maher*

Abstract: The evaluation of the use of alkaline peroxodisulphate digestion with autoclaving or microwave heating for the determination of total phosphorus in turbid lake and river water is described. Procedures were evaluated by the analysis of suspensions (20, 50 and 100 g P/l) of two standard reference materials, National Institute of Environmental Science, Japan No. 3 Chlorella and No. 2 Pond Sediment. Suspensions were prepared by adding these materials to distilled deionized water (pH 6) and homogenisation using shaking, sonification and stirring. Best recoveries of phosphorus were found when the final solution was 0.045 M in potassium peroxodisulphate and 0.04 M in sodium hydroxide and solutions digested in an autoclave at 120°C for 60 min. or heated in a microwave oven at 450 W for 10 min. Complete recoveries of phosphorus (99-103%) from 20, 50 and 100 g P/l Chlorella suspensions were obtained using both autoclave and microwave heating. For the Pond Sediment complete recoveries of phosphorus (99-107%) from the 20 and 50 g P/l suspensions were obtained using both heating methods. Higher recoveries from the 100 g P/l Pond Sediment suspensions were obtained using microwave heating (96 ± 1%) than autoclaving (88 ± 5%). Recoveries of phosphorus compounds (phosphates, and phosphonates) added to distilled deionized water and turbid lake water were near quantitative (91-117%) for both digestion procedures. Further analysis of Pond Sediment suspensions showed that complete recovery of phosphorus (98 ± 1%) from 60 g/l suspensions was achieved with incomplete recoveries (92.3 ± 0.7%, 91 ± 2% and 91 ± 1%) from 70 g P/l, 80 g P/l and 90 g P/l suspensions respectively. Comparison with the APHA-AWWA WPCF, nitric-sulphuric acid digestion method showed no difference in phosphorus measurements for the microwave procedure but that the autoclave procedure gave significantly lower recoveries of phosphorus (p < 0.01), however, differences were only 2-8%.
Phosphorus Sample preparation Sample preparation Reference material Method comparison

"Comparison Of Acid Mixtures In High-pressure Microwave Digestion Methods For The Determination Of The Total Mercury In Sediments By Cold Vapor Atomic Absorption Spectrometry"
Anal. Sci. 1996 Volume 12, Issue 3 Pages 471-476
C. Y. ZHOU, M. K. WONG, L. L. KOH and Y. C. WEE

Abstract: Four acid mixtures, viz. HNO3/H2SO4, HNO3/HClO4, HNO3/HCl and HNO3/HCl/HF, were evaluated as solvents for the high-pressure microwave digestion of environmental sediments for analysis of total Hg by cold vapor AAS. Sediments were dried at 105°C for 4 h and a 300 mg portion of each was digested with 14 mL of each acid mixture (acid ratios given) in an MDS-2000 Microwave System (CEM Corp., Mathews, NC, USA) operated at 630 W power, 150 psi pressure and 200°C for 30 min. After digestion, the samples were cooled until the pressure in the vessels was reduced to 50 psi, filtered and the filtrate was diluted to 50 mL with water. A 10 mL portion of the diluted filtrate was mixed with 0.2 mL 5% KMnO4 solution and a 500 µL portion of the mixture was injected into a Perkin-Elmer FIA System interfaced with a Perkin-Elmer 4100ZL atomic absorption spectrometer (instrumental details given) for measurement of Hg absorbance at 253.6 nm. Best results were obtained with the HCl/HNO3/HF mixed acid solvent. The method was successfully applied to the analysis of three sediment reference materials, viz. NIST SRM 1645 River Sediment, NIES CRM No. 2 Pond Sediment and NRCC BCSS-1 Marine Sediment with recoveries of 92-108%.
Mercury Sample preparation Spectrophotometry Reference material Optimization

"Comparison Of Acid Mixtures In High-pressure Microwave Digestion Methods For The Determination Of The Total Mercury In Sediments By Cold Vapor Atomic Absorption Spectrometry"
Anal. Sci. 1996 Volume 12, Issue 3 Pages 471-476
C. Y. ZHOU, M. K. WONG, L. L. KOH and Y. C. WEE

Abstract: Four acid mixtures, viz. HNO3/H2SO4, HNO3/HClO4, HNO3/HCl and HNO3/HCl/HF, were evaluated as solvents for the high-pressure microwave digestion of environmental sediments for analysis of total Hg by cold vapor AAS. Sediments were dried at 105°C for 4 h and a 300 mg portion of each was digested with 14 mL of each acid mixture (acid ratios given) in an MDS-2000 Microwave System (CEM Corp., Mathews, NC, USA) operated at 630 W power, 150 psi pressure and 200°C for 30 min. After digestion, the samples were cooled until the pressure in the vessels was reduced to 50 psi, filtered and the filtrate was diluted to 50 mL with water. A 10 mL portion of the diluted filtrate was mixed with 0.2 mL 5% KMnO4 solution and a 500 µL portion of the mixture was injected into a Perkin-Elmer FIA System interfaced with a Perkin-Elmer 4100ZL atomic absorption spectrometer (instrumental details given) for measurement of Hg absorbance at 253.6 nm. Best results were obtained with the HCl/HNO3/HF mixed acid solvent. The method was successfully applied to the analysis of three sediment reference materials, viz. NIST SRM 1645 River Sediment, NIES CRM No. 2 Pond Sediment and NRCC BCSS-1 Marine Sediment with recoveries of 92-108%.
Mercury Sample preparation Spectrophotometry Reference material Optimization

"Flavin Mononucleotide Chemiluminescence For Determination Of Traces Of Copper(II) By Continuous-flow And Flow Injection Methods"
Bull. Chem. Soc. Jpn. 1985 Volume 58, Issue 4 Pages 1137-1142
Masaaki Yamada,Hideshi Kanai and Shigetaka Suzuki

Abstract: Flow injection analysis, with chemiluminescence detection, is used to determine traces of copper(II) by means of the flavin mononucleotide-hydrogen peroxide-phosphate buffer system. This permits the determination of copper(II) more selectively than any other chemiluminescence system with a detection limit of 0.03 ng (20 pL sample injection) or 0.06 ng mL-1 (continuous sample flow). The linear range is 3 orders of magnitude, the sampling rate is 120 h-1, and the relative standard deviation is 3.1% for 1 ng Cu(II) (n=10). Iron(II) and chromium(III and VI), the strongest enhancer after copper(II), provide signals 2-3% of that for copper(II). Effect of surfactant micelles on the signal for copper is also discussed. The method is successfully applied to real samples.
Copper Chemiluminescence Micelle Interferences

"Analytical Use Of Luminescence Induced Ultrasonically In Solution. 1. Sonic Chemiluminescence Of Luminol For Determination Of Cobalt(II) At Sub-pg Levels By Flow Injection And Continuous-flow Methods"
Bull. Chem. Soc. Jpn. 1986 Volume 59, Issue 6 Pages 1849-1855
Takayuki Komatsu,Minoru Ohira,Masaaki Yamada and Shigetaka Suzuki

Abstract: The analytical use of the enhancement by Co(II) of the ultrasonically induced chemiluminescence of alkaline luminol solution has been investigated, and a mechanism for the enhancement is suggested. The apparatus was essentially as described previously (Yamada and Suzuki, Chem. Lett., 1983, 783; Yamada et al., Bull. Chem. Soc. Jpn., 1985, 58, 1137); it incorporated an exponential horn (cross-section 0.05 cm2) activated by a 28-kHz, 20-W max. Handy Sonic model UR-20P oscillator (Tomy Seiko Co.). For flow injection analysis of a 10 µL sample, the limit of detection was 0.06 pg of Co(II) and the linear dynamic range was three decades; for continuous-flow analysis these figures were 0.06 pg mL-1 and two decades. A comparison with a conventional Co(II)-catalyzed luminol chemiluminescence method is presented. Results for digests of standard samples agreed with the certified values.
Cobalt Chemiluminescence Sample preparation Method comparison Reference material Ultrasound Linear dynamic range