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Multicomponent samples

Actual water treatment challenges are multicomponent. For example, contamination of groundwater by creosote [8021-39-4], a wood (qv) preservative, is a recurring problem in the vicinity of wood-preserving faciUties. Creosote is a complex mixture of 85 wt % polycycHc aromatic hydrocarbons (PAHs) 10 wt % phenohc compounds, including methylated phenols and the remaining 5 wt % N—, S—, and O— heterocycHcs (38). Aqueous solutions of creosote are therefore, in many ways, typical of the multicomponent samples found in polluted aquifers. [Pg.402]

Gaseous and particulate pollutants are withdrawn isoldnetically from an emission source and collected in a multicomponent sampling train. Principal components of the train include a high-efficiency glass- or quartz-fiber filter and a packed bed of porous polymeric adsorbent resin (typically XAD-2 or polyurethane foam for PCBs). The filter is used to collect organic-laden particulate materials and the porous polymeric resin to adsorb semivolatile organic species (com-... [Pg.2207]

Haaland, D.M., et.al. "Application of New Least-squares Methods for the Quantitative Infrared Analysis of Multicomponent Samples", Appl. Spec. 1982 (36) 665-673. [Pg.191]

Certain disadvantages of this method of analysis should be enumerated. The preparation of standards becomes a major task if a large variation in concentrations of multicomponent samples is expected. The cost of preparing standards for expensive elements is a major consideration however, recovery and purification are possible. [Pg.206]

Bioluminescence can be used for spedfic detection of separated bioactive compounds on layers (BioTLC) [46]. After development and drying the mobile phase by evaporation, the layer is coated with microorganisms by immersion of the plate. Single bioactive substances in multicomponent samples are located as zones of differing luminescence. The choice of the luminescent cells determines the specificity of detection. A specific example is the use of the marine bacterium Vibrio fischeri with the BioTLC format. The bioluminescence of the bacteria cells on the layer is reduced by toxic substances, which are detected as dark zones on a fluorescent background. BioTLC kits are available from ChromaDex, Inc. (Santa Ana, CA). [Pg.183]

D. L. Massart, C. Janssens, L. Kaufman and R. Smits, Application of the theory of graphs to the optimalisation of chromatographic separation schemes for multicomponent samples. Anal. Chem., 44 (1972) 2390-2399. [Pg.626]

The most common method of isolation and sample cleanup involves contacting a filtered aqueous solution with an appropriate immiscible organic solvent in a. aboratory separatory funnel of appropriate size. Some specific examples are discussed later. With multicomponent samples a single solvent or solvent mixture is unlikely to extract all components equally causing discrimination. Ihis discrimination may be useful if the solvent discriminates against the extraction of solutes that are not of interest in the analysis. [Pg.385]

The advantages of imaging (using multichannel detectors or global imaging methods) over conventional mapping experiments are obvious, whenever multicomponent samples have to be investigated ... [Pg.557]

The EEM profiles of fractions obtained by the isolation procedure of the DOM by the XAD resins showed that a fractionation was effective and the XAD-8 eluate is highly representative of the original DOM. Emission scan spectra of DOM and its fractions are featureless, whereas synchronous scan spectra show that the isolation procedure is efficient in separating the original DOM into fractions with different fluorescence properties. The synchronous scan spectra obtained with a wavelength offset of 20 nm present multicomponent samples such as the DOM fractions from landfill leachate. [Pg.308]

C. D. Tran and R. J. Furlan, Spectrofluorometer Based on Acoustic-Optic Tunable Filters for rapid scanning and multicomponent sample Analyses, Anal. Chem. 65, 1675-1681 (1993). [Pg.220]

For any column you are considering, obtain samples from at least three different production lots. Some column manufacturers set aside samples for this specific purpose, but you may obtain a better estimate of variability by simply purchasing columns over a period of time. An effective way to evaluate reproducibility among the columns is to run a standardized separation of a multicomponent sample cocktail. The cocktail should contain at least two different components that elute completely resolved from one another through the course of a shallow linear gradient. Column documentation from the manufacturer usually identifies an analytical cocktail with relative concentrations for each component. [Pg.82]

The atomic absorption characteristics of technetium have been investigated with a technetium hollow-cathode lamp as a spectral line source. The sensitivity for technetium in aqueous solution is 3.0 /ig/ml in a fuel-rich acetylene-air flame for the unresolved 2614.23-2615.87 A doublet under the optimum operating conditions. Only calcium, strontium, and barium cause severe technetium absorption suppression. Cationic interferences are eliminated by adding aluminum to the test solutions. The atomic absorption spectroscopy can be applied to the determination of technetium in uranium and its alloys and also successfully to the analysis of multicomponent samples. [Pg.134]

Has the potential to replace chromatography as a method for more rapid analysis of multicomponent samples. [Pg.112]

Haaland, D.M., et. al. "Multivariate Least-Squares Methods Applied to the Quantitative Spectral Analysis of Multicomponent Samples",/ / / /. Spec. 1985 (39) 73-84. [Pg.103]

In principle, EXAFS information may be obtained for most or all of the elements in a catalyst. Thus, for multicomponent samples, the characterization of local surroundings for all (or almost all) the elements may be obtained. However, we stress that the radial distribution function cannot be transformed into a unique three-dimensional structure. Therefore, the EXAFS technique is not ideal for providing such information and the data representing materials consisting of several different phases may often be too difficult to analyze meaningfully. [Pg.318]

Zone Electrophoresis. In zone electrophoresis multicomponent samples are applied to an electrophoretic medium, most commonly a gel. an electric held is applied, and alter a predetermined length of time or after a certain level of power, current, or voltage has been applied, the electrophoretic medium is inspected for restitution of the sample components. [Pg.554]

C. Multicomponent samples generally have mutually interfering species. Separations are often required. Sometimes, changing the spectral region helps. [Pg.71]

The accuracy of using imaging to measure morphological size distributions in multicomponent samples depends on several factors. First and for most, the effective... [Pg.127]

Most of the applications of FDCD that have been reported have been concerned with the use of this technique as a probe of specific aspects of the chiral environment of biochemical systems. Although, as indicated above, this technique is basically a probe of the molecular ground state, it uses the sensitivity and selectivity of luminescence measurements. FDCD has also been applied to highly scattering and optically dense samples for which polarized absorption measurements are not possible [58,59]. Some of the more recent applications of this technique include its use for on-column detection of chiral molecules in capillary electrophoresis [60], and in a modified phase-modulation spectrofluoremeter [61,62]. The purpose of the latter application is to develop a procedure to determine the distribution of chiral molecules in multicomponent samples [62],... [Pg.236]


See other pages where Multicomponent samples is mentioned: [Pg.386]    [Pg.180]    [Pg.244]    [Pg.34]    [Pg.113]    [Pg.556]    [Pg.622]    [Pg.337]    [Pg.252]    [Pg.25]    [Pg.95]    [Pg.169]    [Pg.278]    [Pg.113]    [Pg.419]    [Pg.111]    [Pg.114]    [Pg.11]    [Pg.97]    [Pg.97]    [Pg.49]    [Pg.180]    [Pg.113]    [Pg.339]    [Pg.112]    [Pg.228]    [Pg.448]   
See also in sourсe #XX -- [ Pg.320 ]




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Multicomponent samples, analysis

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