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Showing 1 to 20 of 63 for “"Chromatographic analysis"”.

  1. The supercritical fluid extraction and chromatographic analysis of fatty acids in blue cheese

    … than long chain FFA. Conventional methods of FFA analysis suffer from limitations such as loss of volatile fatty acids during derivatization of samples and difficulties in extraction and separation of short, medium and long chain fatty acids in a single analysis. Enhanced FFA recoveries from …

    uiuc Repository record for The supercritical fluid extraction and chromatographic analysis of fatty acids in blue cheese (opens in a new tab)

  2. Gas chromatographic analysis of amines and other compounds produced by several species of Clostridium

    Procedures are described for the routine analysis of amines and other compounds produced in bacterial cultures. Whole cultures were grown in six mls of chopped meat-glucose medium, acidified, and extracted with ethyl ether or chloroform to obtain organic acids, alcohols, ketones, aldehydes, and …

    vt Repository record for Gas chromatographic analysis of amines and other compounds produced by several species of Clostridium (opens in a new tab)

  3. Utilization of a scientifically operated charge-coupled device detector for high-performance thin-layer chromatographic analysis

    A high-performance thin-layer chromatographic (HPTLC) separation system coupled with a scientifically operated charge-couple device detector (CCD) has been developed to improve the identification and quantitative analysis of pharmaceutical products and natural toxins. The combination of the fast, …

    arizona-thes Repository record for Utilization of a scientifically operated charge-coupled device detector for high-performance thin-layer chromatographic analysis (opens in a new tab)

  4. An assessment of a liquid-liquid extraction procedure for the gas chromatographic analysis of chloroform in algal media

    … effects of several factors which might alter the analysis of chloroform in aqueous samples by the liquid-liquid extraction (LLE) method developed by Glaze at North Texas State University. A Bendix gas chromatograph (GC) was used. The factors examined were the effect of the ionic strength of the …

    vt Repository record for An assessment of a liquid-liquid extraction procedure for the gas chromatographic analysis of chloroform in algal media (opens in a new tab)

  5. Effluent analysis of model pyrrone compounds by gas chromatography

    A gas chromatographic study was made to quantitatively analyze the effluents produced during the thermal cyclization of several polyimidazopyrrolone (pyrrone) model compounds. The study yielded information on analogous polymeric reactions. The model compounds were programed at 5° C/min from 25° to …

    vt Repository record for Effluent analysis of model pyrrone compounds by gas chromatography (opens in a new tab)

  6. The removal of carcinogenic polycyclic aromatic hydrocarbons by activated sludge

    … was a modified Soxhlet technique followed by gas chromatographic analysis. The amount of Benzo-a-pyrene detected in the effluent, supernatant, sludge filtrate and sludge cake was tabulated to determine the mechanism of removal. The experimental results indicated that adsorption appeared to be.the …

    vt Repository record for The removal of carcinogenic polycyclic aromatic hydrocarbons by activated sludge (opens in a new tab)

  7. The amino acid composition of chinchilla fur in relation to the fur-chewing syndrome

    … time consuming end less reproducible than the chromatographic analysis. With the exception of proline, glycine, and leucine, higher values were obtained fer the mine acids using the microbiological methods than with the column fractions. The greatest difficulty was encountered in analyzing the …

    vt Repository record for The amino acid composition of chinchilla fur in relation to the fur-chewing syndrome (opens in a new tab)

  8. Pure culture and metagenomic approaches to investigate cellulose and xylan degradation

    … of sugars from xylan was observed through gas chromatographic analysis between the parental and fusant cultures. Genome shuffling was observed in 16S rRNA genes after protoplast fusion. Finally, one putative endo-β-1,4-glucanase was discovered in a metagenomic library created from …

    uoit Repository record for Pure culture and metagenomic approaches to investigate cellulose and xylan degradation (opens in a new tab)

  9. STUDIES ON THE ANALYSIS AND THE FATE OF ORGANIC POLLUTANTS IN THE ENVIRONMENT

    This thesis deals with the analysis and the fate of pesticides in the environment. In the first part of the thesis, new techniques such as solid-phase extraction, solid-phase microextraction, and electrochemical detection, were studied and applied to the analysis of pesticides and their degradation …

    nus Repository record for STUDIES ON THE ANALYSIS AND THE FATE OF ORGANIC POLLUTANTS IN THE ENVIRONMENT (opens in a new tab)

  10. Electrically Controlled Formation and Release of Admicelles for Solid Phase Extraction

    … the purpose of analyte preconcentration prior to chromatographic analysis are presented. The surfactant layer serves as the “stationary phase” in a solid phase extraction sorbent scenario. Analytes are adsorbed on this layer, and then released from the solid phase via surfactant removal. The …

    wku-diss Repository record for Electrically Controlled Formation and Release of Admicelles for Solid Phase Extraction (opens in a new tab)

  11. Derivation and chromatographic separation of acid indole auxins

    … compounds has been used to facilitate their gas chromatographic analysis. The three phytochemically significant indole acids; 3-indole acetic acid, 3-indole propionic acid, and 3-indole butyric acid along with an analog, D-tryptophan, are four compounds which have been analyzed by this method. A …

    vt Repository record for Derivation and chromatographic separation of acid indole auxins (opens in a new tab)

  12. Effect of processing and storage conditions upon canned apple sauce headspace gas composition

    … Procedures were developed for sampling for chromatographic analysis gas from cans with high vacuum and small headspace, and for calculating gas volumes. A minimum headspaoe hydrogen was observed in samples within the pH range 3.45-3.75, in products of consistency within the range common to …

    vt Repository record for Effect of processing and storage conditions upon canned apple sauce headspace gas composition (opens in a new tab)

  13. Characterization of structure and enzymic activity of endo-l, 4-β-D-glucanases purified from Trichoderma viride

    … lose activity above pH 7.0. High pressure liquid chromatographic analysis permitted determination of enzymic rates of reaction with purified cellooligosaccharides. Endoglucanases II, III and IV display higher activities as the chain-length of cello oligosaccharide substrates progresses from two to …

    vt Repository record for Characterization of structure and enzymic activity of endo-l, 4-β-D-glucanases purified from Trichoderma viride (opens in a new tab)

  14. Organinių alavo junginių mikroekstrakcija ir dujų chromatografinis nustatymas /

    … and apply the most appropriate technique for the analysis of aqueous samples. In real samples OTC exist in cationic form, are non-volatile and polar, so before gas chromatographic analysis OTC must be derivatized. Sodium tetraethylborate has been used for the derivatization. Derivatization …

    vilnius Repository record for Organinių alavo junginių mikroekstrakcija ir dujų chromatografinis nustatymas / (opens in a new tab)

  15. Microextraction and gas chromatographic determination of organotin compounds /

    … and apply the most appropriate technique for the analysis of aqueous samples. In real samples OTC exist in cationic form, are non-volatile and polar, so before gas chromatographic analysis OTC must be derivatized. Sodium tetraethylborate has been used for the derivatization. Derivatization …

    vilnius Repository record for Microextraction and gas chromatographic determination of organotin compounds / (opens in a new tab)

  16. Use of antioxidant activity and flavonoid levels to assess the quality of commercially available solid dose Sutherlandia frutescens products

    … conditions and total phenol, antioxidant and chromatographic analysis was conducted on these samples. Samples of each of the SCP were hydrolyzed using HCL and then analyzed using HPLC to test the stability of the flavonoids present in each product. The SCP investigated in this study physically …

    western-cape Repository record for Use of antioxidant activity and flavonoid levels to assess the quality of commercially available solid dose Sutherlandia frutescens products (opens in a new tab)

  17. STEREOCHEMICAL STUDIES OF 1,2-DIAMINOCYCLOHEXANE AND SOME OF ITS DERIVATIVES

    … was found to be most convenient for routine analysis. Gas chromatographic analysis after the Eschweiler-Clarke N-methylation was found to give a faulty isomer ratio unless special precautions were taken to insure complete reaction, since the cis isomer was found to undergo unusually slow …

    unh-thes Repository record for STEREOCHEMICAL STUDIES OF 1,2-DIAMINOCYCLOHEXANE AND SOME OF ITS DERIVATIVES (opens in a new tab)

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