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Supelco columns

We obtained the best results with the Carbopack B-DA/4% Carbowax 20M, 80-120 mesh Supelco column, 2000 x 2 mm. It was initially conditioned for 21 h at 245°C, but the normal running temperature is 175°C. The injector/detector temperature is 200°C and a flame ionization detector is used. A glass sleeve is fitted to the injector and the glass wool plug removed from the column inlet. The carrier gas is nitrogen with a flowrate of 40 ml min at 310 kN m. The sample solution (9 ml) is mixed with 1 ml of pivalic acid solution (1.5% m/v) as internal standard. Then 1 ml of this solution is mixed with 1 ml 0.3 M oxalic acid solution and 3 ml deionized water before injecting 1 pi into the septum. [Pg.160]

Table E1.2.1 Typical Retention Times of Common Sugars on Supelco Columns... Table E1.2.1 Typical Retention Times of Common Sugars on Supelco Columns...
The temperature inside the reactor is measured with seven thermocouples (Type K). To avoid channelling, the thermocouples are placed only 5 mm into the bed. The temperature inside the manifold is also measured, as well as at several points at the outlet pipe. The pressure in the manifold and inside the reactor is also measured with the help of pressure transducers. In order to take gas samples, a sample line has been built (Fig. 4). It consists of a steel condenser and three glass bottles in an ice bath, a moisture filter (silica gel), a pump and a gas flowmeter. A sample of O.S ml is taken from the gas sample line with a syringe and inserted into a gas chromatograph from SRI Instruments equipped with a TCD detector and a Supelco column (Carboxen I0(X)). [Pg.432]

Reversed-phase hplc has been used to separate PPG into its components using evaporative light scattering and uv detection of their 3,5-dinitroben2oyl derivatives. Acetonitrile—water or methanol—water mixtures effected the separation (175). Polymer glycols in PUR elastomers have been identified (176) by pyrolysis-gc. The pyrolysis was carried out at 600°C and produced a small amount of ethane, CO2, propane, and mostiy propylene, CO, and CH4. The species responsible for a musty odor present in some PUR foam was separated and identified by gc (Supelco SP-2100 capillary column)... [Pg.354]

This is the only column we have found that separates the cellosolves (monoalkyl ethers at ethylene glycol) and the other solvents including the xylenes. (See Supelco GC Bulletin 824.)... [Pg.117]

The analysis demonstrates the elegant use of a very specific type of column packing. As a result, there is no sample preparation, so after the serum has been filtered or centrifuged, which is a precautionary measure to protect the apparatus, 10 p.1 of serum is injected directly on to the column. The separation obtained is shown in figure 13. The stationary phase, as described by Supelco, was a silica based material with a polymeric surface containing dispersive areas surrounded by a polar network. Small molecules can penetrate the polar network and interact with the dispersive areas and be retained, whereas the larger molecules, such as proteins, cannot reach the interactive surface and are thus rapidly eluted from the column. The chemical nature of the material is not clear, but it can be assumed that the dispersive surface where interaction with the small molecules can take place probably contains hydrocarbon chains like a reversed phase. [Pg.225]

Samples were fractionated by size on stainless steel columns packed with TSK-GEL ToyoPearl gel filtration medium, (Supelco Inc., Bellefonte, PA) in 50 mM NH4AC, pH 5.2. For HW-55 S (fractionation range for dextrans 1000-200,000 daltons) and HW-50 S (fractionation range for dextrans 500-20,000 daltons), the column was 10 x 500 mm and the flow rate was 1 ml/min. For HW-40 S (fractionation range for dextrans 100-7000 daltons),... [Pg.80]

Stationary phase. Supelcosil Cig ABZ (Supelco Scientific, Bellefonte, PA, USA) was the most often employed support and gave the best correlations. This stationary phase should be selected in a first instance with a geometry adapted to the application for conventional gradient experiments, supports of 150X4.6 mm, 5 pm represent a good choice while a shorter column (i.e. 50 mm or lower) with smaller particle size (i.e. 3-3.5 pm) must be preferentially selected for fast gradient analysis. [Pg.346]

Eused-silica capillary columns, 25-m, SE54-CB-1 or OV-1701 (Supelco)... [Pg.1096]

Solid-phase extraction (SPE) cartridge, LC Si 2-g, 12-mL (Supelco), or equivalent ABC Laboratories Model SP 1000 gel permeation chromatograph system equipped with a 2.5 x 32.0 cm glass column of Bio-Beads S-X3 Select 200-400 mesh (ca 50 g, Bio-Rad Laboratories) preconditioned with ethyl acetate-cyclohexane (1 1, v/v), or equivalent... [Pg.1309]

GC analysis for methanol, 1-propanol, 1-butanol, pyrrolidine, N-methylpyrrolidine, 2-pynolidinone, N-methyl-2-pyrrolidinone, gamma-butrolactone, dimethylsuccinate, and N-butyl-2-pyrrolidinone was performed with a Hewlett-Packard Model 5890 Gas Chromatograph equipped with a 30-meter, 0.53 mm I.D., 0.50-micron film, Nukol capillary column (Supelco, Bellefonte, PA) and a flame ionization detector (FID). [Pg.149]

FIGURE 18.4 NPLC chromatogram of Triton X-100. Conditions Supelco LC-NH2 column, 15 cm x 4.6 mm and 3 pm particles linear gradient of 80/20/0 (heptane/tetrahydrofiiran/ methanol) to 0/90/10 in 40 min at a flow rate of 1 mL/min evaporative light scattering detection. [Pg.431]

Gundersen and Blomhoff (1999) used online dilution with online SPE to measure vitamin A (retinol) and other active retinoids in animal plasma. The intention of online dilution in this application was on optimizing SPE extraction conditions rather than on peak focusing during analytical separation. An SPE cartridge packed with Bondapak C18 materials (37 to 53 jt/M, 300 A, Waters, Milford, Massachusetts) and a reversed-phase analytical column (250 x 2.1 mm inner diameter, Superlex pkb-100, Supelco, Bellefonte, Pennsylvania) were controlled by a six-port switching valve (Rheodyne, Cotati,... [Pg.283]

Their method included a Waters 2795 Alliance HT (high throughput) HPLC system with an integrated autosampler. The stationary phase was a Supelco C18 column (250 x 4.6 mm, 5 fim). The mobile phase consisted of solvent A (water containing 2mM ammonium acetate and 0.1% formic acid) and solvent B (methanol containing 2mM ammonium acetate and 0.1% formic acid). The mobile phase was delivered at a flow rate of 0.6 mL/min in a step gradient mode 50% solvent B from 0 to 0.4 min and 100% solvent B from 0.4 to 0.8 min. [Pg.308]

Aspec is designed to receive up to 108 samples. The system is compatible with most standard disposable extraction columns. Analytichem Bond-Elut Baker SPE, Supelco Supelclean, Alltech Extract Clean, etc. There is a choice of more than 20 different stationary phases. [Pg.49]

Gas chromatography conditions are as follows Supelco fused silica capillary SPB-1 column (30 m, 0.32-mm ID, 0.25 micrometers df), 100°C initial temperature, 280°C final temperature, 10°C/min. The following retention times were obtained diphenylacetaldehyde (6.7 min), trans-stilbene oxide (7.4 min), Tischenko product (18.2 min). [Pg.50]


See other pages where Supelco columns is mentioned: [Pg.214]    [Pg.234]    [Pg.1003]    [Pg.1124]    [Pg.28]    [Pg.234]    [Pg.1003]    [Pg.1124]    [Pg.620]    [Pg.90]    [Pg.417]    [Pg.214]    [Pg.234]    [Pg.1003]    [Pg.1124]    [Pg.28]    [Pg.234]    [Pg.1003]    [Pg.1124]    [Pg.620]    [Pg.90]    [Pg.417]    [Pg.63]    [Pg.70]    [Pg.423]    [Pg.17]    [Pg.25]    [Pg.261]    [Pg.262]    [Pg.262]    [Pg.296]    [Pg.370]    [Pg.183]    [Pg.390]    [Pg.410]    [Pg.146]    [Pg.239]    [Pg.52]    [Pg.438]    [Pg.136]    [Pg.283]    [Pg.91]    [Pg.365]   
See also in sourсe #XX -- [ Pg.25 ]

See also in sourсe #XX -- [ Pg.19 , Pg.23 ]

See also in sourсe #XX -- [ Pg.19 , Pg.23 ]




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