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Wide-bore columns

The particles of the bed of an analytical column are held by the column wall and by the porous frits at the column top and column end. Specific frit systems have been developed by column manufacturers to enable a homogeneous distribution of the flow across the column. Wide bore preparative columns contain distributors at both ends for optimum sample distribution. Both the quality of the frits and the distributors significantly affect the performance of a chromatographic column. While for analytical columns the bed is supported by friction between the column wall and the packed particles, the particles of wide bore preparative columns are subjected to a much higher mechanical stress. [Pg.54]

Direct injection rehes on vaporization processes to introduce sample into the column. However, it lacks a purge activation function, a septum purge flow, or secondary cooling (Fig. 5). The direct injection mode is used with packed columns or wide-bore (0.53-mm-I.D.) capillary columns. Wide-bore columns are used as higher-efficiency replacements for packed columns without the need to extensively modify the packed-column injector. [Pg.363]

Lillsunde and Korte (75) previously reported a screening procednre covering 300 substances, including drugs of abuse and metabolites, in which they used a combination of packed and capillary columns. Wide-bore capillary columns have also been used successfully for the screening and confirmation of drugs in forensic toxicological samples (76). [Pg.912]

A wide-bore column containing a particulate packing material. [Pg.564]

Although aimed at the introductory class, this simple experiment provides a nice demonstration of the use of GG for a qualitative analysis. Students obtain chromatograms for several possible accelerants using headspace sampling and then analyze the headspace over a sealed sample of charred wood to determine the accelerant used in burning the wood. Separations are carried out using a wide-bore capillary column with a stationary phase of methyl 50% phenyl silicone and a flame ionization detector. [Pg.610]

Purity. Gas chromatographic analysis is performed utilizing a wide-bore capillary column (DB-1, 60 m x 0.32 mm ID x 1.0 //m film) and a flame ionization detector in an instmment such as a Hewlett-Packard 5890 gas chromatograph. A caUbration standard is used to determine response factors for all significant impurities, and external standard calculation techniques are used to estimate the impurity concentrations. AHyl chloride purity is deterrnined by difference. [Pg.35]

G. Gastello, A. Timossi and T. G. Gerbino, Analysis of haloalkanes on wide-bore capillary columns of different polarity connected in series , J. Chromatogr. 522 329-343 (1990). [Pg.332]

I Most of the GC conditions given in this book are for 0.25-mm ID columns, but 0.32- or 0.53-mm ID columns also can be used. The wide bore fused silica columns are found to be more inert, probably because of the greater film thicknesses. A splitter arrangement with a jet separator is used with 0.53-mm ID columns. This arrangement shown in Figure 11.1 has the advantage of simultaneous flame ionization quantitation. [Pg.362]

Fast chromatography involves the use of narrow-bore columns (typically 0.1-mm i.d.) that will require higher inlet pressures compared with the conventional wide-bore capillary columns. These columns require detectors and computing systems capable of fast data acquisition. The main disadvantage is a much-reduced sample loading capacity. Advances in GC column technology, along with many of the GC-related techniques discussed below, were recently reviewed by Eiceman et... [Pg.737]

At this point it is worth considering the demands made on the instrumentation for operation with wide bore columns and, in particular, the adaptation of analytical Instruments for this purpose [596,597]. The pump requirements for preparative separations differ from those in analytical HPLC as the ability to generate high flow rates at moderate backpressures is crucial to the efficient operation of wide bore columns. A flow rate maximum of 100 ml/min with a pressure limit of 3000 p.s.i. is considered... [Pg.767]

The chromatographic procedure [11] is carried out using a wide-bore fused-silica column 30 m long and 0.53 mm in internal diameter coated with macrogel 20 000 2-nitrotere-phthalate with film thickness of 0.5 pm. In addition, for chromatography, helium should be used as the carrier gas at a flow rate of 8.0 mL/min using a flame ionization detector. [Pg.226]

The lncos-50 is a relatively low-cost benchtop instrument as opposed to the research grade instruments discussed earlier. The gas chromatography-mass spectrometer transfer lines allow it to be used with either the Hewlett Packard 5890 or the Varian 3400 gas chromatographs. The Incos 50 provides data system control of the gas chromatography and accessories such as autosampler or liquid sample concentration. It can be used with capillary, wide-bore or packed columns. It performs electron ionization or chemical ionization with positive or negative detection. It also accepts desorption or other solids controls. [Pg.76]

In direct injection, all injected material is carried onto the column by the mobile phase. This eliminates the possibility of sample discrimination in the inlet, but can overload capillary columns and so is more commonly used with packed columns and wide-bore capillary columns. [Pg.2]


See other pages where Wide-bore columns is mentioned: [Pg.168]    [Pg.376]    [Pg.676]    [Pg.168]    [Pg.376]    [Pg.676]    [Pg.610]    [Pg.610]    [Pg.776]    [Pg.106]    [Pg.247]    [Pg.347]    [Pg.16]    [Pg.30]    [Pg.74]    [Pg.86]    [Pg.112]    [Pg.132]    [Pg.134]    [Pg.151]    [Pg.253]    [Pg.326]    [Pg.424]    [Pg.489]    [Pg.548]    [Pg.592]    [Pg.627]    [Pg.211]    [Pg.252]    [Pg.62]    [Pg.548]    [Pg.374]    [Pg.375]    [Pg.100]    [Pg.117]    [Pg.143]    [Pg.1127]    [Pg.71]    [Pg.160]    [Pg.252]   
See also in sourсe #XX -- [ Pg.300 ]




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Glass capillary columns, wide-bore

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