New Products Analog peak analyzer Model 3004 can process signals from ir detectors, mass spectrometers, scintillation detectors, etc. The system holds the magnitudes of up to three consecutive analog peaks. The differential between the highest positive input and the two most negative inputs is necessary to provide a mean output. Outputs include the three peak amplitudes, a sum that is the absolute value of the average peakto-peak voltage, and a gated sum. Several units can be paralleled and out puts multiplexed into a single channel if desired. Operating from ± 1 5 Vdc at 50 mA and + 5 Vdc at 100 mA, the in strument requires a minimum peak in put of 50 mV; accuracy is ± 1 % or 20 mV, whichever is greater; drift is less than l % / 8 hr. Sampling-time intervals can be provided over any preselected time periods. Model 3004 measures 5 X 9 X 0.7 in.; quantity price for 5 - 1 0 units is $515. Electromechanical Sys tems Div., ABA Industries, Inc. 813546-3571 413
Inert columns now come in all sizes Chromatronix now offers chemically inert columns with bores from 1 mm to 2 inches for all types of chromatography: ion exchange, gel filtration, gel permeation, adsorption and partition. All columns can produce rapid, high-resolution separa tions using fine packings and pressures up to 500 psi. Π Available for use with the columns are water jackets, flow switching valves, sample injection valves, fittings, tubing, and constant-flow pumps. The assembled equipment will handle nearly any solvent, since only glass, Teflon and Kel-F touch the stream. • Send for 8page technical bulletin on methods of increasing the resolution and speed of chromatography using the most advanced equipment available today.
CHROMATRONIX Chromatronix, Incorporated, 2743 Ninth St., Berkeley, Calif. 94710. Phone (415) 841-7221.
Improved photovoltaic infrared detec tors for operation in the 8- to 12-μ re gion of the far ir have lead tin telluride detector elements comparable in de tectivity to copper- or mercury-doped germanium units without the need for cooling to the low temperatures re quired by the latter devices. Lead tin telluride operates at an optimum at liquid nitrogen temperatures. Peak spectral response of the units is 1 0 - 1 1 μ; barium fluoride windows transmit more than 9 0 % of the radiation. IR101 models are packaged in small glass dewars potted in aluminum shells with coaxial connectors. $1995. Ray theon Co. 617-862-6600 414 Model 334 laboratory bath/circulator features —20 to + 7 0 ° C operation with control accuracy of ± 0 . 0 1 °C. Stain less steel bath area has 7V2 gal ca pacity and may also be used with ex ternal circulating to cool instruments. Coolant may be pumped at 3 % g P m rate with 5-ft head. Model 334 mea sures IV2 i n - X 1 5 % in. χ 27 in. long. $595. Hotpack Corp. 215-333-1700
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you get next to nothing IWT's Laboratory De-Ionizers give you pure water in limited amounts (5 gph). The Universal Cartridge at $10.95 re moves all ionizable solids except free silica and C0 2 . At $12.95, the Research Cartridge removes silica and C 0 2 leaving nothing in the water but 4 PARTS PER BILLION OR LESS IMPURITY (on most city water supplies). When two Research Cartridges are operated in a Duplex fixture, water with a resistivity of 15 meg ohms-cm is regularly available. Duplex operation is economical—you can completely use up the left cartridge while you still get good water from the right cartridge. Replacing the spent car tridge with a fresh one returns full po tential. You know you are getting pure water; an accurate resin color change tells you so.
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Model 72 proportional temperature con troller can maintain temperatures as closely as ± 0 . 0 0 1 °C over a range of 0 to 120°C. Three dials set the control point. Company thermistor probes sense temperatures of the medium be ing controlled. Probes are interchange able and available in configurations to fit most applications. $360. The com pany also has a Model 71A temperature controller covering the range from —10 to + 1 2 0 ° C as closely as ±0.03°C. $245. Yellow Springs Instrument Co. 513-767-7242 416
CIRCLE 2 7 O N READER SERVICE CARD
82 A • ANALYTICAL CHEMISTRY, VOL. 43, NO. 14, DECEMBER 1971
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Bul. DX-470 describes the expanded tWT cartridge line. Five different models meet the need for varying levels of purity. Six page, 4-color brochure describes fixtures, suggests systems, and contains prices. Yours if you ask for It.
ILLINOIS WATER TREATMENT COMPANY 840 CEDAR ST., ROCKFORD, ILL. 61105
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CIRCLE 61 O N READER SERVICE CARD