NEW
CHEMICALS REAGENTS MATERIALS
CHEMICALS
Nonionic Surfactant Analysis
Silicon Nitride
A ready-to-use solution, "Nonionic Reagent", has been introduced by Fisher Scientific Co. for use in quantitative analysis for water-soluble nonionic surfactants of known chemical structure. Fisher says that the turbidimetric method for which the solution is designed calls for visual comparison, but that it can be adapted also for instrumentation. The company adds that it is applicable to all water-soluble surfactants and polyglycols containing ethylene oxide. This would include adducts derived from alkylphenols, aliphatic alcohols, fatty amines, alkyl mercaptans, polyalkylene glycols, and fatty amides. Nonionic Reagent forms a white turbidity with nonionic surfactants in very dilute solutions, formation being essentially complete in 15 minutes. Lower limit of the method is said to be one to 10 p.p.m. C-1
Haynes Stellite Co., division of Union Carbide Corp., is producing Haynes silicon nitride, a new material formed by the reaction of nitrogen with silicon metal at temperature of approximately 2400° F. This product resists molten aluminum even when continuously immersed for 3000 hours in it. It is not wetted by other nonferrous metals and currently is being tested for processing and melting germanium for the transistor industry, where contamination cannot be tolerated. Silicon nitride is, as announced by the manufacturer, stable under chemical contact with hydrochloric, nitric, phosphoric, and sulfuric acids. It is not recommended, however, for use with caustic soda nor hydrofluoric acid. It has been used in temperatures up to 3000° F. in neutral or reducing atmospheres, and up to 2200° F. in oxidizing atmospheres. It withstands re-
peated thermal shocks and its low coefficient of expansion prevents marked contractions and expansions during heating and cooling. It retains its room temperature strength above 2000° F. Haynes announces parts are available in many shapes and sizes. C-4
Aluminum Test Solution A product for accurate determination of microgram amounts of aluminum has been announced by Fisher Scientific Co. as having originated in the Victor Chemical laboratories. This method of fast colorimetric determination of aluminum in phosphoric acid bright dip baths is possible because, with this solution, negative interference is minimized by regulation of sample size, pH, and reagent concentration. Fisher catalog number for the test solution is So-V-20. C-5
Lead N i t r a t e A refined white crystalline grade of lead nitrate is being offered by Hummel Chemical Co. A typical analysis shows 99.2% purity with moisture 0.72%, thus allowing total impurities, excluding water, to average 0.08%. Lead chloride is absent. One use for the chemical, reports the manufacturer, is as an analytical reagent. C-2
STOPCOCKS CATALOG No. 804(3
HEAVY
WALL
TUBING
Polyphenols and Alkyd Derivatives Monsanto Chemical Co. announces that its research has developed fluids which are outstanding in their ability to resist radiation and thermal damage. These are polyphenyl compounds and certain of their isopropyl derivatives. Five of these are available in commercial quantities and four others have been evaluated with respect to physical properties. Alkylation and eutectic mixtures of them have given increased range of fluidity and improvement in both low temperature and high temperature properties. Monsanto states that several fluids are being evaluated as coolants for nuclear power and others are being evaluated as radiation-resistant imprégnants for capacitators. Other applications are known because these compounds are so unusuallv stable. C-3
MINIMUM BORE REDUCTION
HEAVY
TAPERED
FLANGE
HEAVY WALL TUBING For Rugged Durability
HEAVY TAPERED FLANGE Prevents Breakage at Barrel
MINIMUM BORE REDUCTION Bore of Side Arms is Equal to or Larger than Bore of Plug on All Sizes In Stock for Immediate Delivery at Vineland, N.J. and Louisville, Ky.
ACE GLASS INCORPORATED VINELAND
NEW
JERSEY
LOUISVILLE, KY., BOX 996
For further information, circle number 97 A on Readers' Service Card, page 101 A VOL. 30, NO. 10, OCTOBER 1958
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97
A
