Reverse-phase gas chromatography

OTMAB concentration (%) Adhesion strength (MPa) Tg from Reversed-phase gas chromatography Calorimetry... 

In the majority of cases the compatibility of the polymers is characterized by the glass-transition temperature Tg, determined by methods such as dilatometry, differential scanning calorimetry (DSC), reversed-phase gas chromatography (RGC), radiation thermal luminescence (RTL), dynamic mechanical spectroscopy (DMS), nuclear magnetic resonance (NMR), or dielectric loss. The existence of two... 

The hardening of the boundary layer of epoxy and polyester compositions was studied by IR spectroscopy (of repeatedly disturbed total internal reflection—RDTIR) on a UR-20 spectrometer. A KRS-5 prism N =18, C = 45°) and a germanium prism N =14, C = 45°) were used for simulation of the substrate surface. The thickness of a polymer layer was 0.5-1 nm for the element made of germanium and 2-3 nm for KRS-5. Inhibition of polyester resin polymerization by atmospheric oxygen was eliminated by applying a polyethylene film to the surface of a system to be hardened. The thickness of the applied epoxy and polyester composition was up to 20-30 nm. To evaluate the glass-transition temperature and the polymer-solvent interaction parameter, we used reversed-phase gas chromatography. Basalt-1 and basalt-2 (see below) served as fillers and as a model substrate. The... 

Many forms of chromatography have been used to separate mixtures of quinoline and isoquinoline homologues. For example, alumina saturated with cobalt chloride, reversed-phase Hquid chromatography, and capillary gas chromatography (gc) with deactivated glass columns have all been employed (38,39). 

R. J. Senorans, J. Villen, J. Tabera and M. Heiraiz, Simplex optimization of the direct analysis of free sterols in sunflower oil by on-line coupled reversed phase liquid chromatography-gas clnomatography , 7. Agric. Food Chem. 46 1022-1026 (1998). 

One of the first examples of the application of reverse-phase liquid chromatography-gas chromatography for this type of analysis was applied to atrazine (98). This method used a loop-type interface. The mobile phase was the most important parameter because retention in the LC column must be sufficient (there must be a high percentage of water), although a low percentage of water is only possible when the loop-type interface is used to transfer the LC fraction. The authors solved this problem by using methanol/water (60 40) with 5% 1-propanol and a precolumn. The experimental conditions employed are shown in Table 13.2. 

Senorans, R J., Reglero, G., and Herraiz, M., Use of a programmed temperature injector for on-line reversed-phase liquid chromatography-capillary gas chromatography, /. Chromatogr Sci, 33, 446, 1995. 

Thomas etal. [72] used pyrolysis gas chromatography-mass spectrometry as a fast economic screening technique for polyaromatic hydrocarbons. Thomas used reverse-phase liquid chromatography with atmospheric pressure chemical ionization mass spectrometry/mass spectrometry for the determination of polycyclic aromatic sulphur heterocycles in sediments. 

K. Grob and Z. Li, Coupled reversed-phase liquid chromatography-capillary gas chromatography for the determination of atrazine in water , J. Chromatogr. 473 423 -430 (1989). 

K. Grob, Concurrent eluent evaporation with co-solvent trapping for on-line reversed-phase liquid chromatography-gas chromatography. Optimization of conditions , J. Chromatogr. 477 73-86 (1989). 

T. Hyotylainen, K. Jauho and M-L. Riekkola, Analysis of pesticides in red wines by online coupled reversed phase liquid chromatography with a vaporizer/precolumn solvent split/gas discharge interface ,/. Chromatogr. 813 113-119(1997). 

H. G. J. Mol, J. Staniewski, H.-G. Janssen and C. A. Cramers, Use of an open-tubular trapping column as phase-switching interface in on-line coupled reversed-phase hquid chromatography-capillary gas chromatography , J. Chromatogr. 630 201 -212 (1993). 

T. Hyotylainen and M-L. Riekkola, Direct coupling of reversed-phase liquid chromatography to gas chromatography , J. Chromatogr. 819 13 - 24 (1998). 

G. P. Blanch, J. Villen and M. Herraiz, Rapid analysis of free erythrodiol and uvaol in ohve oils by coupled reversed phase hquid chromatography-gas chromatography , J. Agric. Food Chem. 46 1027-1030 (1998). 

Figure 11.12 GC analysis of (a) urine sample spiked with opiates 3 p.g/ml) and (b) blank urine sample. Peak identification is as follows 1, dihydrocodeine 2, codeine 3, ethylmor-phine 4, morphine 5, heroin. Reprinted from Journal of Chromatography, A 771, T. Hyotylainen et al., Determination of morphine and its analogues in urine by on-line coupled reversed-phase liquied chromatography-gas chromatography with on-line derivatization, pp. 360-365, copyright 1997, with permission from Elsevier Science.

E. C. Goosens, D. de Jong, G. J. de Jong and U. A. Th Brinkman, Reversed-phase liquid chromatography coupled on-line with capillary gas chromatography. II. Use of a solvent vapor exit to increase introduction volumes and introduction rates into the gas chromatograph , J. Microcolumn Sep 6 207-215 (1994). 

T. Hyotylainen, H. Keski-Hynnila and M. L. Riekkola, Determination of morphine and its analogues in urine by on-line coupled reversed-phase liquid chromatography-gas chromatography with on-line denvatization, J. Chromatogr. A 771 360-365 (1997). 

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