NEW PRODUCTS Correction
SPEED
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A new gas chromatograph, Model 800 Vapor Fractometer is a dual c o l u m n dual flame detector gas chromatograph. The instrument has 17 heating rates from 0.5° to 5 0 ° per minute up to 4 0 0 ° C. It is ideally suited for food flavor analyses and other temperature-programmed or isothermal analyses where very high sensitivity must be combined with high column capacity and wide operating temperature range. Several modes of operation are possible with the instrument. Both columns can be used to produce a bal-
anced column mode. Effects of substrate elution, or of trace impurities in the carrier gas stream, are automatically cancelled and the instrument's detector measures only the components of the separated sample as they are eluted from the column used for the analysis. In another mode, two different columns may be mounted and used alternately for comparison of sample behavior on different substrates, or for saving time in changing from problems requiring one type column to those requiring a second type column. An important new capability which this instrument offers is that of differential analysis. Here, two samples are simultaneously injected into identical columns and a differential chromatogram representing only differences between the samples is recorded. A unique differential detector developed by Perkin-Elmer for the Model 800 consists of two flame ionization detector units housed in a special chamber with electrodes arranged to form a differential circuit (patent pending). Each flame is oppositely polarized, and both have a common output electrode. The detector is thus sensitive only to the presence of components in one flame that are not present in the other. The detector amplifier will operate either galvanometric or potentiometric recorders, as well as accessory integration equipment. A precision signal attenuator covers a dynamic range of 1 to 500,000 in 18 steps for accurate measurement of both trace and major sample components. Perkin-Elmer Corp., Norwalk, Conn.
Digitized infrared spectrophotometer is a general purpose system described as providing the " m i s s i n g l i n k " between laboratory analytical instruments and the many general purpose computers now in use.
The new spectrophotometer will automatically produce analysis data not generally obtainable by conventional methods. In addition, the system offers greater flexibility, higher accuracy, and lower frequency of errors
The June issue contained a New Products item (No. 406) concerning a new gas chromatograph. The photograph accompanying the description of the instrument showed, however, a digitized infrared spectrophotometer. The photograph of the Model 800 Vapor Fractometer is shown below with its description. The digitized infrared spectrophotometer is also featured.
A Coors Shapiro Speedi Filter disc greatly increases the efficiency of Buchner funnels through the utilization of a major portion of the filter paper surface. In some filtering operations, filtration is limited to those areas of the filter paper which lie directly over the holes in the Buchner funnel plate. With the Coors Shapiro Speedi Filter disc interposed between the plate and the filter paper, you utilize completely the entire area of the filter paper. The speed of filtration is greatly increased as is the quantity of suspension which can be filtered by a single sheet of paper. What's more, the t o t a l surface is uniformly coated. Coors filter discs are immediately available through your laboratory supply dealer, in four standard sizes or in an assortment of the four sizes. INSIST THAT YOUR LABORATORY PORCELAIN WARE CARRY THIS MARK OF DEPENDABILITY
COORS U.S.A. COORS PORCELAIN COMPANY, GOLDEN. COLORADO
Circle No. 28 on Readers' Service Card 102 A
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ANALYTICAL CHEMISTRY
