Column accessories

Cp/, Estimated cost of column accessories, e.g. platforms and ladders. 

Mouse recombinant Single chain antibody Fragment variable (ScFv) produced in E.Coli RPAS Purification Module 17-1362-01 HiTrap Anti-E column, accessories, pre-made buffers for 20 purifications 0.17 mg ScFv/5 ml... 

The Pioneer MPS option, described in Section 3.1, is a 16-column accessory that can be added to the PE Biosystems Pioneer peptide synthesis system. A... 

The separation operation called distillation utihzes vapor and hquid phases at essentially the same temperature and pressure for the coexisting zones. Various lands of devices such as r andom or sti uctui ed packings and plates or tr ays are used to bring the two phases into intimate contact. Trays are stacked one above the other and enclosed in a cyhndrical shell to form a column. Pacldngs are also generally contained in a cyhndrical shell between hold-down and support plates. A typical tray-type distillation column plus major external accessories is shown schematically in Fig. 13-1. 

Design Features There are three classes of thickeners, each differentiated by its drive mechanism (1) bridge-supported, (2) center-column supported, and (3) traction drives. The diameter of the tank will range from 2 to 150 m (6.5 to 492 ft), and the support structure often is related to the size required. These classes are described in detail in the subsection Components and Accessories for Sedimentation Units. ... 

Gel filtration separations are performed in an aqueous environment and the requirement on chemical resistance is therefore modest. Most column tubes and accessories (e.g., support net, sealings) withstand the solvent mixtures sometimes used in aqueous SEC such as 20% ethanol, 3 M guanidinium hydrochloride, 6 M urea, or 0.1 M HCl and 1 M NaOH, the last two being used for cleaning the packed column (see Section V). 

In addition to standard liquid injection there are many GC accessories which can provide different methods of sample introduction to the column, such as HS, SPE, SFE, TD, TG, Py, etc. Examples of such GC-FTIR devices are TD-GC-FT1R (with a cryostat interface) and PyGC-FTIR. 

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. 

Column selector valves can be added on as accessories to allow column switching for multi-dimensional chromatography (to increase the resolution of very complex samples such as in proteomics) or for automatic column selection (up to six columns) to facilitate methods development using different columns. 

Samples of both fulvic and humic acids were suspended in methanol and methylated with diazomethane. Both H and spectra of the free acids were obtained, at 299.94 MHz and 75.42 MHz respectively, on a Varian XL-300 spectrometer having a Nicolet TT-100 PET accessory. Spectra were obtained in D2O, in a 12-mm tube, with deuterated TSP (sodium 3-(trimethylsilyl)propionate-, , 3,3- 4) added as internal reference. GC/MS of methylated acids was conducted on a Hewlett-Packard Model No 5995 GC/MS/DA system equipped with a fused silica capillary column (12 m x. 020 mm ID, Hewlett Packard) internally coated with crosslinked methylene silicone. Infrared spectra were obtained with solid samples dispersed in KBr pellets, by using a Beckman IR-33 spectrophotometer. The various absorption peaks in IR and NMR were interpreted conventionally (9-10). 

Majors, R. E., New chromatography columns and accessories at the 2002 Pittsburgh Conference. Part 1. LC-GC North America, 20,248-266,2002. 

When the column is used with reliable accessories, the chromatogram is fairly reproducible and the parameters of separation very well controlled. Thus it is possible to obtain, during successive analyses of the same sample conducted within a few hours, chromatograms that can be superimposed to within a second. 

The table below contains values of the retention factor k for four refinery gases, studied at three different temperatures upon the same capillary column (length L = 30cm, internal diameter = 250 pm), whose stationary phase is of type SE-30. The chromatograph is supplied with a cryogenic accessory. 

The accessibility to the column and ease of installation of accessories is important if columns are to be changed often and if various accessories such as valves are required for the particular applications the instrument will need to satisfy. 

The inlet system, detector, and any heated accessories should have separate temperature-controlled ovens. They should not be in the column oven since it is not desirable that the temperature of these parts change during the analysis. These separate ovens should also be well isolated from the column oven since many detectors will have response changes that will result in baseline drift and quantification errors. The connecting lines between oven and these heated parts, especially the detector, should be short and should not have any "cold spots"... 

The commercial FIAS FI accessory for atomic spectroscopies has also been used to couple TRU-Resin column separations to ICP-MS, as described by Epov et al.51-53... 

A Perkin-Elmer MPF-2A Fluorescence Spectrophotometer was used to determine the excitation and emission wavelengths required for achieving maximum fluorescence intensity for the pesticides studied. The MPF-2A contained a 150 watt xenon arc and an excitation monochromator with a grating blazed at 300 nm as the excitation unit a Hamamatsu R 777 photomultiplier tube (sensitivity range 185 - 850 nm) and an emission monochromator grating blazed at 300 nm as the emission detection unit. A DuPont Model 848 Liquid Chromatograph was used for HPLC (Figure 2). The accessory injection device included a Rheodyne Model 70-10 six-port sample injection valve fitted with a 20 y liter sample loop. A Whatman HPLC column 4.6 mm x 25 cm that contained Partisil PXS 1025 PAC (a bonded cyano-amino polar phase unspecified by the manufacturer) was used with various mobile phases at ambient temperature and a flowrate of 1.25 ml/minute. 

The GC determination of metal halides is complicated by the instability in chromatographic systems and different analytical solutions. Fluorides and chlorides are the halides that are used most often for different groups of metals the former are more volatile, but they also tend to be more reactive. The GC analysis of metal chlorides and fluorides necessitates highly inert column packings and inert chromatographic accessories, particularly the injection port, material of the column and the detector. Conversion of metal ions into halides involves different halogenation techniques. Direct reactions of metals... 

The GC shall be capable of temperature programming and be equipped with all required accessories, such as syringes, gases, and a capillary column. The GC injection port shall be designed for capillary columns a splitless or an on-column injection technique is recommended. A 2 pL injection volume is assumed throughout this method however, with some GC injection ports, other volumes may be more appropriate. A 1 pL injection volume may be used if adequate sensitivity and precision can be demonstrated. 

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