Liquid chromatographic analyses

Phosnic 390 from two different lots, IJ-3 and IL-22, was obtained and used for pol3rmerization without further purification. According to gas and liquid chromatographic analyses, the Phosnic 390 sanqjles consist of 91% cyclic trimer and 9% cyclic tetramer (i.e., octa-chlorocyclotetraphosphazene). 

Clark et al. [81] determined the time course of A-acetylation of primaquine by Streptomyces roseochromogenous and Streptomyces rimosus by quantitative high performance liquid chromatographic analyses of the culture broths. The A-5-bistri-fluoroacetyl derivative of primaquine was used as an internal standard in the analysis for the quantitation of primaquine A-acetate in microbial culture broths. S. roseochromogenous forms the highest level of primaquine A-acetate at 24—36 h after substrate addition, while S. rimosus is slower in its acetylation, peaking at 3 days after substrate addition. The formation of a novel dimeric compound from the reaction of primaquine with 8-(4-phthalimido-l-methylbutylamino)-6-methoxy quinoline is also reported. 

The preparation of volatile derivatives of carbohydrates has permitted the development of useful gas-liquid chromatographic analyses... 

Results obtained in glass apparatus are summarized in Figure 1. The unsaturation falls off nearly linearly after a short induction period. After the hydroperoxide functional groups attain their maximum, the olefin disappearance decreases and becomes nonlinear as it is consumed by reaction to form polymeric dialkyl peroxide functions. The maximum concentration of polymeric dialkyl peroxide occurs well after the maximum alkenyl hydroperoxide concentration, giving the appearance of a sequential oxidation mechanism. Infrared and gas-liquid chromatographic analyses showed that hydroxylic derivatives, carbonyl derivatives, and lower molecular weight olefins continued to build up as by-products as the oxidation proceeded, as does the acidity titer. 

O Adeola, JG Buchanan-Smith, RJ Early. Gas and high-performance liquid chromatographic analyses of amino acids in soybean meal, corn and triticale. J Food Biochem 12 171-181, 1988. 

However, Popp et al. [148] desorbed extracted polycyclic aromatic hydrocarbons by ultrasonic treatment of the stir bar in acetonitrile or acetonitrile water mixtures in order to perform liquid chromatographic analyses of the extract. 

Although structural elucidation of lignans is not a difficult task, the similarities between the structures can create problems. In particular, the determination of stereochemistry at the chiral center requires NOE/ NOESY NMR experiments and/or X-ray analyses. The enantiomeric excesses of the known lignans (+)-lariciresinol, (-)-secoisolariciresinol and (+)-taxiresinol, isolated from Japanese yew T. cuspidata roots, were determined by chiral high-performance liquid chromatographic analyses [78] except for (+)-pinoresinol (77% enantiomeric excess), they were found to be optically pure by Kawamura et al. In an earlier study, the presence of taxiresinol in Taxus species was reported by Mujumdar et al. [69] after they had isolated it from the heartwood of T. baccata, although they did not study its stereochemistry. 

Liquid chromatographic analyses with ICP-MS detection may be divided into categories according to the mode of chromatography used reversed-phase, ion-pair, micellar, ion-exchange, and size-exclusion chromatography. 

Korhonen IOO, Mantykoski KM (1989b), J. Chromat. 477 327-336. Gas-liquid chromatographic analyses 1. Retention, dispersion and selectivity of polychlorinated dibenzo-p-dioxins and dibenzofurans44... 

Steryl conjugates in liquid chromatographic analyses are most often quantified using external standard methods, which, depending on the... 

Liquid Chromatographic Analyses. Analyses of about half the samples by the standardized method of liquid chromatographic separation are presented in Table IX. lii addition to asphaltenes and minerals, all contained large amounts of resins and small amounts of oils that are mostly hydrocarbons. Similar results were obtained whether the samples were analyzed as bitumens or as asphalts. In general, however, the bitumens gave somewhat more resins and hydrocarbons, whereas asphalts gave more asphaltenes. With Farukhabad 404, which was analyzed both as bitumen and as asphalt, the difference in asphaltenes was 8%. 

Table IX. Liquid Chromatographic Analyses of Asphalts and Bitumens "...

V. Pacakova and P. A. Leclercq, Gas chromatography-mass spectroscopy and high performance liquid chromatographic analyses of thermal degradation products of common plastics.. Journal of Chromatography, 555, 229-237, (1991). 

Lensmeyer GL, Onsager C, Carlson IH, and Wiebe DA. Use of particle-loaded membranes to extract steroids for high-performance liquid chromatographic analyses improved analyte stability and detection. J. Chromatogr. A 1995 691 239-246. 

Reagents. The water used in this study was distilled from a potassium permanganate-sodium hydroxide solution and passed through an XAD-2 column (38). The acetonitrile and sodium chloride were spectro and reagent grades, respectively. All of the PAHs used were obtained commercially and were reported to contain less than 3% impurities by their respective manufacturers. Gas and liquid chromatographic analyses of these materials supported these claims. 

Ricci, M.C. Cross, R.F. High-performance liquid chromatographic analyses of sulphonamides and dihydrofolate reductase inhibitors. I. Separations in methanol-modified solutions. J.Liq.Chrom. Rel.Technol, 1996, 19, 365-381... 

Derivatization is used in a number of liquid chromatographic analyses of biochemical substances in order to obtain a sufficiently sensitive and selective detection. 

Table VII. Conditions of Reported Non-Stereospecific High-Performance Liquid Chromatographic Analyses. 

Table Vm. Conditions of Steieospecific High-Performance Liquid Chromatographic Analyses for Sotalol. 

S. Perlman and J. Kirschbaum, High-performance liquid chromatographic analyses of the antihypertensive drug captopril, J. Chromatogr., 1981, 206, 311-317. 

Interpretation of Instrumental Data. If instructed to do so, discuss any instrumental data, such as gas-liquid chromatographic analyses and spectral data that you have obtained or are provided in the textbook. 

In traditional fermented foods in Asia such as soy sauce (shoyu), fermented soybean-barley miso) in Japan, and pickles such as kimchi in Korea and tsukemono in Japan, various organic acids, such as acetic acid, lactic acid, and citric acid, are detected by chemical and liquid chromatographic analyses. The largest amount of lactic acid is contained in Japanese pickles, tsukemono, followed by acetic, citric, formic, mahc, and glutamic acids (Tomomatsu et al. 1972). More than 13 species of lactic acid bacteria and 10 species of yeast isolated from six kinds of tsukemono were identified by 16S rRNA sequence analysis (Asada and Ueno 2009). However, no acetic acid bacteria were detected. By cultivatiOTi of isolated yeast strains, acetic acid, citric acid, and succinic acid were detected in the fermentation broth. However, more careful experiments would be required to conclude that the special yeast can form acetic acid. 

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