Trend analysis sediments

A recent trend in particle analysis has been the introduction of personal computer-based automation (3). Sophisticated software packages can be used to automate and speed up the analysis. In some cases these computers can even carry out continuous process control (qv) (see Computer technology). The latest machines also allow the measurements of smaller particles and can detect a wider range of sizes. Machines based on light-scattering principles are being more widely accepted by the industry because of speed. An average analysis takes from 1—2 min, whereas those based on sedimentation principles require from 10—120 min. 

Biomolecule Separations. Advances in chemical separation techniques such as capillary zone electrophoresis (cze) and sedimentation field flow fractionation (sfff) allow for the isolation of nanogram quantities of amino acids and proteins, as weU as the characterization of large biomolecules (63—68) (see Biopolymers, analytical techniques). The two aforementioned techniques, as weU as chromatography and centrifugation, ate all based upon the differential migration of materials. Trends in the area of separations are toward the manipulation of smaller sample volumes, more rapid purification and analysis of materials, higher resolution of complex mixtures, milder conditions, and higher recovery (69). 

Roelandts I (1991) quoted by Braun T and Zsindely S (1991) Trends Anal Chem 10 106-109. ScHANTZ MM, Benner BA Jr, Chester SN, Koster BJ, Hehn KE, Stone SF, Kelly WR, Zeisler R, and Wise SA (1990) Preparation and analysis of a marine sediment reference material for the determination of trace organic constituents. Fresenius J Anal Chem 338 501-514. 

Parkinson D-R, Dust JM (2010) Overview of the current status of sediment chemical analysis trends in analytical techniques. Environ Rev 18(NA) 37-59... 

Chemical analysis of the Meza River and its tributaries revealed significant heavy metal pollution of the upper Meza River sediments with lead, zinc, and some molybdenum, cadmium and arsenic enrichments. The trend of Cd and As is similar to trend of Pb and Zn, which is in agreement with the fact that Cd and As are associated with Pb and Zn in ore minerals (Strucl, 1984 Fux Gosar, 2007). In the lower Meza valley, these heavy metal concentrations decreased somewhat. 

This value is the median determined from a meta-data analysis (Long. E. R. and L. G. Morgan [1991]. The Potential for Biological Ejfects of Sediment-Sorbed Contaminants Testing in the National Status and Trends Program, NOAA Technical Memorandum NOS OMA 52, 175 pp.) The lower threshold at which 10% of the data demonstrated toxicity was 35 ppm. 

Diaz-Cmz M.S., M.J.L. de Alda, and D. Barcelo (2003). Environmental behavior and analysis of veterinary and human drugs in soils, sediments and sludge. Trends in Analytical Chemistry 22 340-351. 

Forstner, U. (2004), Traceability of sediment analysis, Trends Anal. Chem., 23, 217-236. 

His 40+ publications have dealt with biogeochemical processes that control the alkalinity of surface waters, the geochemisty of dilute seepage lakes, sediment chemistry, the interpretation of water-quality trends, regional analysis of water quality, modeling lake eutrophication, lake management, reservoir water quality, and nonpoint source pollution. He recently joined the faculty of the Department of Civil Engineering at Arizona State University. 

Quevauviller, Ph. (1998a) Operationally defined extraction procedures for soil and sediment analysis. I. Standardization. Trends Anal. Chem., 17, 289. 

Kuster, M., M. Jose Lopez de Alda, and D. Barcelo. 2004. Analysis and distribution of estrogens and progestogens in sewage sludge, soils and sediments. Trends Anal. Chem. 23 790-798. 

From Table 4 data it follows that specific activity of Cs in bottom sediments has a trend of decreasing over time. Under the used method of analysis concentrations of other gamma-emitting isotopes in samples of bottom sediments were below the detection limit. 

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