Organic carbon analysis

The nomenclature of organic carbon is described in detail in Chapter 2 and in the Glossary. While there is a difference in definition between total organic carbon (TOQ and dissolved organic carbon (DOC), which is that the DOC is that part of TOC which passes through a 0.45 om filter, in this thesis the terms are used interchangeably. 

Membranes can remove large amounts of NOM from waters. It is a challenge to correctiy measure the organic carbon in waters at very low levels and prior to the purchase of an instrument several instruments were compared. Once a choice was made, the instrument was optimised and extensively tested for potential problems and errors. 

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Table 1.9 Total organic carbon analysis as supplied by Dohrmann... 

To calculate the osmotic pressure we used values of osmotic coefficients from ref. (lOj. Total organic carbon analysis (Beckman 914A] of samples from the water filled compartment verified that the membranes are impermeable to sucrose, so that the reflection coefficient a is equal to unity. 

Winnett, W.K. and M.P. Murphy. 1994. A novel sample introduction technique for combustion total organic carbon analysis in aqueous materials. Talanta 41 1627-1630. 

Cappelli, F., P.D. Goulden, J. Lawrence, and DJ. MacGregor. 1978. Determination of the adsorption efficiency of the organics carbon adsorbable standard method by dissolved organic carbon analysis. J. Environ. Sci. Health A 13 167-176. 

Strege, M.A., Stinger,T.L., Farrell, B.T., Lagu, A.L., Total organic carbon analysis of swab samples for the cleaning validation of bioprocess fermentation equipment. BioPharm April 1996. 

We wish to thank M. Helena Nogueira for conducting the total organic carbon analysis. We also gratefully acknowledge Dr. J. Seabra e Barros for help with the elemental analysis. 

Hearst, P. J. Determination of Oil in Water by Organic Carbon Analysis U.S. Navy Civil Engineering Laboratory Port Hueneme, CA, 1979. 

Size exclusion chromatography (SEC) has been used to measure molecular weight (MW) distribution of humic substances (3, 6-9). Coupled with detection methods such as molecular fluorescence spectroscopy and dissolved organic carbon analysis (7), electrochemical detection (9), and atomic emission spectroscopy (5), SEC has been used extensively to study humic-metal complexes. A major disadvantage of SEC is that it does not provide adequate resolution for separating humic materials as they do not appear to be made up of distinct fractions with large differences in MW. 

Aqueous organic carbon analyzers helped revolutionize humic studies during the last decade. Not only could organic carbon measurements be made quickly and accurately on any water sample, but organic carbon analysis, used as a monitoring detector like conductivity and fluorescence, opened a new dimension in experimental design and approaches. In conjunction with other methods, the amount and distribution of humic substances in water in relation to other carbon-containing compounds could be determined. 

Total Organic Carbon Analysis (TOC). TOC analysis was carried out on a Beckman 915A Total Organic Carbon analyzer according to the standard procedures used with this instrument. 

Additionally, the oxidation efficiency of the DOC analyser may also depend on the organic characteristics and similar problems may be encountered. It is strongly suggested to couple at least two techniques for organic carbon analysis. 

Photocatalytic oxidation for total organic carbon analysis. Analytica Chimica Acta 233, 1 71-1 79. 

Rouwenhorst RJ, Jzn JF, Scheffers WA, Vandijken JP. Determination of protein-concentration by total organic-carbon analysis. J Biochem Biophys Methods 1991 22(2) 119-128. 

Block copolymer of PVA and 1,1 dicarboxylated malonate copolymer. M = 9000-24,000 VA block content 8-72% Biochemical oxygen demand, molecular weight, CO2 evolution, organic carbon analysis River water culture isolates (aerobic) River sediment or anaerobic activated sludge (anaerobic) [136]... 

Matthews, R.W., Abdullah, M., and Low, G.K.-C., Photocatalytic oxidation for total organic carbon analysis, Analytica Chimica Acta 233, 171, 1990. 

G. Cauwet. HTCO method for dissolved organic carbon analysis in seawater influence of catalyst on blank estimation. Mar. Chem., 47 55-64,1994. 

Biwald, C. E., W. K. Gavlick, Total organic carbon analysis and FTIR to determine residues of cleaning agents on surfaces,/. AOAC Int., 1997,80,1078-1083. 

The abnormally low concenttation of SDS needed to form the surface surfactant structures may be explained by the preferential adsorption of SDS into self-assembled C TAB aggregates at the silica surface. Adsorption experiments, using total organic carbon analysis to determine the total amount of adsorbed surfactant and inductively coupled plasma spectroscopy to determine the SDS concentration through the sulfm emission line, have shown that nearly all the SDS added adsorbed at the solid-liquid interface. Hence, the molecular ratio at the interface was estimated to be on the order of 1 10 instead of 1 100 in bulk solution. This is particularly interesting because... 

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