READERS' INFORMATION SERVICE Optical Equipment Ovens & Incubators Oxygen Bombs pH Indicators DH M te Photometers' . . . . . . Polarimeters
59 129 127 63 40 i « '. '. '. '. '. 58, 114 12
Polyamiaocarboxylic Acid Compounds. . Potentiometer Recorders Preaees
Pumps Radioactivity Safety Devices Radiochemicals Reagents Recorders Refrigerated Baths _ . Rotameters
5 13
32, 64 87, 133 124 66, 95 40, 44, 65 68,86,144,148 10 . 3
Spectra Spectrograph^ Equipment Spectrometers
85 24 71, 149
Spectrophotometers. . .2,22,69,108,112,151 Spencer Photomicrographic Cameras . . 20 SUrrer8
60
Syringes
47
Table Tops Taper Sleeves
27 90, 125 36 23 126
combustion apparatus
7 141
Testing Machines Thermistors Titrators Triethyl Phosphate
137 92 1, 34, 82 153
Valves Viscometers
71, 117 30
Ware, Alumina
70
Ware, Fused Quartz Safety Enclosures Sample Changers Sample Handling Systems Scalers Scales
oniaer
91
Ware_ GIaB8
39> 42> 122>
u 2
Ware> plastic Ware, Porcelain
38
X-Ray Spectrometry
45
s6
for determination of halogens, sulfur, traces of metals, etc., in organic materials
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READERS' INFORMATION SERVICE Analytical Chemistry 430 Park Avenue New York 22, Ν. Υ.
A simplified technique for catalytic com bustion of organic materials in oxygen. The procedure converts organic materials into soluble combustion products which are then analyzed by usual inorganic gravimetric or volumetric methods. Consisting of a heavy wall flask, of borosilicate glass, with ground glass stopper with attached platinum wire gauze sample carrier and specially cut low ash paper sheets which serve as sample holders. In use, sample is placed in the platinum carrier and the flask is charged with a small amount of absorbing liquid and with freeflowing oxygen. The paper is ignited; stopper with sample is seated in the flask and flask inverted at an angle. Combustion proceeds at high temperatures and combustion prod ucts are absorbed in the liquid. Titrations can then be made directly in the flask. Results compare favorably, i.e., within ± 0.3%, with conventional methods. Because of low cost, time and space saving features, the method is finding wide use for many sub stances which undergo complete combustion. See Wolfgang Schoniger, Mikrochimica Acta, 1956, Heft 1-6, pp. 869-876. 6470-E. C o m b u i t l o n A p p a r a t u s , T h o m a · SchSnlger (Schdnlger Fla»k), as above described, 300 ml capacity, for samples up to 10 mg 28.35 6 4 7 0 - G . Ditto, as above but with 500 ml flask, far iamples up to 100 mg 29.0Ό
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ANALYTICAL CHEMISTRY
