Detector model

Detectors Model 410 differential refractive index (Waters Corporation) Model 100 differential viscometer (Viscotek Corporation) Dawn-F multiangle laser light-scattering photometer (Wyatt Technology)... 

A stainless steel column (4.6 mm internal diameter by 250 mm length) packed with 7 micron Zorbax ODS (Dupont) was equilibrated with 82 % Acetonitrile in water at a flow rate of 2.0 ml/min. provided by a Spectra Physics Model 87(X) pump and controller. The effluent was monitored at 230 nm using either a Tracor UV-Visible detector Model 970A or a Jasco Uvidec UV detector Model 1(X)-V. Peaks were recorded and calculated on a SpectraPhysics recording integrator. Model 4200 or Model 4270. Samples of 0.5 mg/ml in toluene were applied to the column automatically with a Micromeritics Autosampler Model 725 equipped with a 10 pi loop. 

Such products were detected in the UV, using a Waters multiwavelength detector (Model 490 E). The wavelenght chosen for the ethyienic nonionic (Genapol), rich... 

The detector model is capable of simulating both vapour and liquid detection systems. So far, about a dozen different detector systems are available. The detector model input signal (see 2.1) consists of i) a time concentration profile, ii) the identity of the chemical warfare agent (HD, GB, VX or L) and iii) the relative air humidity (RH < 80% or RH > 80%). 

The liquid detector model simulates the behaviour of detection papers, which are in operational use by the Dutch and many other Defence forces. It simulates whether or not a paper will show a visible coloration, depending on deposition density and droplet sizes. 

Molecular weights were determined using a Waters high-pressure GPC instrument (Model 6000 A pymp, a series of five p-Styragel columns (10s, 10s, 10, 103, 500 A), Differential Refractometer 2401 and UV Absorbance Detector Model (440) and a calibration curve made by well fractionated polyisobutylene standards. 

An HPLC system, equipped with a Waters solvent delivery system (M-45), two PLgel 20 p,m Mixed-A columns (300 x 7.5 mm) with 20 p,m guard column (50 x 7.5 mm) (Polymer Laboratories, Amherst, MA) and a refractive index detector (model 2410) (Waters, Milford, MA), can be used to study the molecular size and size distribution (e.g. molecular weight and weight distribution) of starch. 

GPC Analysis. Molecular weight characterizations were carried out using a Waters 840 Gel Permeation Chromatograph equipped with both an ultraviolet (UV) (Model 481) and a refractive index (RI) detector (Model 410). Two Ultrastyragel columns, in the running order of 1,000 and 10,OOOA pore... 

Detection of A280nm Spectrophotometric Detector Model LC-75 (Perkin-Elmer, USA)... 

Modular isocratic HPLC with ED detection HPLC pump 515 (Waters), Injector 7725i (Rheodyne), Pulsation Reduced (Portman Instruments), Coulochem Detector Model 5100A (ESA), Analytical Cell 5011 (ESA), and PC with chromatography software (SCPA). 

McNabb TJ, Cremesti AE, Brown PR, Fischl AA. High-performance liquid chromatography/evaporative light-scattering detector techniques for neutral, polar, and acidic lipid classes a review of methods and detector models. Sem Food Anal 1999 4 53-70. 

Samples of fatty acid esters were analyzed with a gas chromatograph interfaced with a mass selective detector (Model QP 5050A Shimadzu) using a capillary column PE-5 (20 m x 0.18 mm x 0.25 mm). The following... 

Figure 2. Flow Sheet of the HPLC Unit for Rapid Protein Analysis. A binary gradient system with gradient controller, Model 21500 pumps,Model 2152 controller, Pharmacia, Piscataway, NJ, U.S.A. (A), Variable wavelength UV-Visible detector, Model LC 95, Perkin Elmer, Norwalk, CT, U.S.A (B), Constant temperature circulating bath, Model DL-8 Haake Buchler, Saddlebrook, NJ, USA (C), Heat exchangers (D), Sampling valve,...

Emf measurements were made with a Leeds and Northrup K-5 potentiometer equipped with a Leeds and Northrup DC null detector (Model 9829). The temperature of the bath was regulated to within 0.02 K. Details of the experimental procedure, including preparation of the electrodes (19), cell design, preparation of solutions, purification of the hydrogen gas, and other experimental aspects, have been reported elsewhere (13,14). 

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