Chromatograms temperature-programmed

Figure 7.27 Constructed Gram-Schmidt chromatogram of a temperature-programmed packed-capillary LC separation of 4.8 ig Irgafos P-EPQ dissolved in DMF temperature programme 50°C for 8min, 4°Cmin-1 up to 140°C. Legend 1, mono-P-EPQ 2, Irgafos 168 3, 4,3 -P-EPQ 4, oxidised 4,4 -P-EPQ 5, 4,4 -P-EPQ. After Bruheim et al. [511]. From I. Bruheim et al., Journal of High Resolution Chromatography, 23, 525-530 (2000). Wiley-VCH, 2000. Reproduced by permission of Wiley-VCH.

Fig. 21.14. Temperature-programmed capillary GC-MS total ion chromatograms for kerosene (upper trace) and Moth-Knox pesticide (lower trace). Note the similarity in the pattern of peaks, with the exception of the large peak in the pesticide sample (at a retention time of about 12.5 min). The mass spectrum and the retention time of this peak both corresponded to a standard of naphthalene.

Obtain chromatograms of the three standards and also the pure gasoline (0% added). Give the column plenty of time to clear between injections—temperature programming may be useful. 

Automatic operation of the metering pump allows repetitive injections with unattended operation. Precise control of the carrier-gas flow ensures stable chromatograms and reproducible timings for collection of samples. Independent column oven and vaporizer temperatures are available up to 300°C and these can be operated with temperature programming or isothermally. The latter option is the most common. 

Figure 3. Capillary Gas Chromatogram of Volatiles from Soil, Chromatographic data adsorption 4 h on Tenax TA desorption 8 min at 200 C column fused silica 0.3 mm, 20 m, SE33 temperature programming 40 to 230 C at 5 C/min carrier gas helium (50 cm/s),...

Figure shows a typical chromatogram of of Filmex C run under the above conditions The chromosorb column will give good separation of the components under various temperature programs. The initial temperature can be below 100°C to give a wider peak for... 

Figure 3. Total ion chromatogram of extractable organics in a typical lot of Ambersorb XE-340 resin (SP-2100,10-m capillary column, temperature program 50(2)-250 at 5 °C/min, 1.0-pL splitless injection). 1, naphthalene 2,1- or 2-methylnaphthalene 3, biphenyl 4, 1,V-biphenyl, 2- or 3-methyl 5, fluorene 6, anthracene-phenanthrene 7tl- or 2-phenylnaphthalene 8, pyrene 9, fluoranthene 10, terphenyl isomer 11, benzo[b]naphthothiophene isomer 12, binaphthalene isomer 13, benzofluoranthene isomer. (Reproduced from...

Figure 6.18. Comparison of isothermal and temperature-programmed chromatograms. Sample of Cg to C2o normal paraffins on 15 foot x 1/8 inch column packed with 10% OV-1 on Chromosorb W.

Gas chromatograms of fully hydrogenated fish triglycerides on a 1.83-m glass column, 3% JXR on 100/120 mesh Gas Chrom Q, flame Ionization detector injector 350°C detector 320-360 C, temperature programmed at 4°C/min (210-375°C) (7). 

Figure D1.2.2 Sample GC chromatogram of the FAME from butter fat (Sweet Cream Butter, Wisconsin Grade AA, Roundy s, Milwaukee, Wise.) prepared using the sodium methoxide method (see Basic Protocol 2). Equipment DB-23 fused silica capillary column, 30 m x 0.32 mm i.d., 0.25 pm film thickness, FID detector. Temperature, injector 225°C detector 250°C. Column (oven) temperature program 100°C initial, hold 4 min, ramp to 198°C at 1.5°C/min, hold 10 min. Total run time was 80 min. Split injection.

On a 30-m nonpolar column, the chromatogram for a hydrocarbon standard C7 to C2owith a temperature program of 2°C/min starting at 35°C will take 90 min to run with an alkane eluting every 6 to 8 min. With arate of 6°C/min, the run will take 40 min, with an alkane eluting every 2 to 3 min. 

Figure G1.5.8 is a chromatogram for lemon oil. The temperature program is modified compared to that of orange oil.

The odor concentrates were separated by temperature-programmed gas chromatography on a 20% Carbowax 20M column. Typical chromatograms obtained from the distillate—i.e., the odor concentrate isolated... 

Figure 12.7 Chromatograms of a polycarbonate sample (a) microcolumn SEC trace (b) capillary GC trace of introduced fractions. SEC conditions fused-silica (30 cm X 250 mm i.d.) packed with PL-GEL (50 A pore size, 5 mm particle diameter) eluent, THF at a Flow rate of 2.0ml/min injection size, 200 NL UV detection at 254 nm x represents the polymer additive fraction transferred to LC system (ca. 6 p,L). GC conditions DB-1 column (15m X 0.25 mm i.d., 0.25 pun film thickness) deactivated fused-silica uncoated inlet (5 m X 0.32 mm i.d.) temperature program, 100 °C for 8 min, rising to 350 °C at a rate of 12°C/min flame ionization detection. Peak identification is as follows 1, 2,4-tert-butylphenol 2, nonylphenol isomers 3, di(4-fert-butylphenyl) carbonate 4, Tinuvin 329 5, solvent impurity 6, Irgaphos 168 (oxidized). Reprinted with permission from Ref. (14).

Figure 4. Total ion gas chromatogram of GPC fraction 3 of S02-solubles (Figure 2). Columns 5% Dexsil 300 on 100/120 Chromosorb H-WP, 1/8 in o.d. X 8 ft, carrier gas 20 mL helium/min, temperature program 80°-270° C at 2°/min for 40 min followed by 4°/min. See Table 1 for peak identification.

Figure 6. Total ion gas chromatogram of the THF extract of S02-insoluble of SRC from West Virginia subbituminous coal. GC conditions were same as in Figure 4 except the temperature program of 80° to 270° C at 4°/min. See Table III for...

FIGURE 6.4 Gas chromatograms of a mixture containing C5-C15 normal alkanes using temperature-programming rates of (a) 10, (b) 20, and (c) 30°C/min. The silicon column was native non-polar, and the carrier gas was air. In all cases, the initial column temperature was 30°C, and the temperature program was initiated at the time of injection [598]. Reprinted with permission from the American Chemical Society. 

In many publications, flame ionisation detectors and temperature programming were employed, the latter especially in the identification of less volatile oils. For routine investigations, isothermal conditions have been adopted in order to allow quicker analysis, but at the sacrifice of some fine detail in the chromatogram [8],... 

A Varian 3400 gas chromatograph equipped with a flame ionization detector and a nonpolar fused silica capillary column (60 m x 0.25 mm i.d. 0.25 pm thickness, SPB-1, Supelco, Inc.) was used to analyze the volatile compounds from the model systems. The injector temperature was 250°C, and the detector temperature was 260°C. The flow rate of the helium carrier gas was 1 mL/min and the split ratio was 50 1. The temperature program consisted of a 10 min isothermal period at 35°C, temperature increases of 2°C/min from 35°C to 120°C and of 4°C/min from 120°C to 235°C, and a 40 min. isothermal period at 235°C. The chromatograms were plotted and integrated on a Varian 4270 integrator. Linear retention indices for the volatile compounds were calculated using n-paraffin standards (C6-C25 Alltech Associates) as references according to the method of Majlat and co-workers (5). 

Figure 17. SIM chromatograms of TPTM (a), TPTE (b), and methylvendex derivative (v) on 3% OV-7 with temperature programming to 265°C...

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