The Chemical World This Week
OCTOBER
23, ΐ9βι
SUSSA CONCENTRATES • N-Hydroxy-2-acetylaminofluorene is the first of a series of intermediates that forms when cancer-producing 2-acetylaminofluorene (AAF) is fed to animals. Dr. James Miller and his wife, Dr. Elizabeth Miller, of the University of Wis consin identified the intermediate after they iso lated it from the urine of rats which were fed AAF. They identified the N-hydroxy part of the molecule as a metabolic product in living tissues. Thus, some normal body products may occasionally turn into carcinogenic N-hydroxy forms and account for the appearance of some types of cancer, the Wisconsin scientists say. • Thermometric titration promises to become a standard analytical procedure, Dr. David N. Hume of Massachusetts Institute of Technology told the Ninth Detroit Anachem Conference. Reasons for this are the development of sensitive thermistor sensing elements with fast response, and the use of an automatic device that delivers reagent at a constant rate. In thermometric titrations, solution temperature is plotted against volume of titrant. A sharp break in the curve shows the end point. Thermometric titrations have been applied to neutralization, complexation, redox, and precipitation reactions. Since thermometric titrations aren't affected by the solvent's dielectric constant, they can be used in nonaqueous media. They can also be used to titrate liquid solutions with gaseous reagents and, in some cases, to titrate gases with other gases in the absence of a liquid phase. • The International Recrystallizer Process has been licensed to W. L. Badger Associates, Ann Arbor, Mich., which will handle engineering for the process. The salt purification process was patented by the International Salt Co., Clarks Summit, Pa. The International Recrystallizer makes a very high purity evaporated salt from solid rock salt or solar salt in a continuous opera tion. The process eliminates the tedious and expensive chemical brine purification processes ordinarily required, International says. • The amount of ions in automobile engine ex haust is conditioned by the engine's oil consump tion, the type of oil used, and the general con dition of tie engine. There is essentially equal charge (positive and negative) distribution, Ralph W. Burhans, Standard Oil (Ohio), and John V. Derau, Philco Corp., told the Interna tional Conference of Ionization of the Air, held
last week at the Franklin Institute, Philadelphia. There are small amounts of small ions in the ex haust, the ions generally being charged particu late matter rather than free charged molecular species. Although the exhaust gases have a space charge, the charge is insignificant com pared to the mass of the evolving particles (of which at least 90% can be removed electrostati cally ). The general effect of all common gasoline additives is to increase the ion content, nearly doubling it over that of straight gasoline. ί Unattended pneumatic unloading of bulk materials stored in several hoppers is pos sible with a manifold and valve system under test at General American Transportation Corp., Chicago. GATX has had the system installed in Dry-Flo hopper cars hauling malt and rice, and has also made tests with prilled polyethylene, Leroy Kramer, Jr., told an American Society of Mechanical Engineers bulk handling symposium in Minneapolis. The manifold is a pipe that circles through all six of the car's discharge hop pers. Within each hopper, a section cut from the bottom of the pipe permits the material to unload pneumatically. When the hopper is empty, increased pressure differential across the valve in the empty hopper forces a flexible diaphragm to rise to close the opening. • Pilot plant quantities of three high tempera ture niobium alloys are being made by Westinghouse. Called B-66, B-77, and B-33, the alloys can withstand temperatures from 1800° to 3000° F. B-33 is a 96% niobium, 4% vanadium alloy. B-66 consists of niobium, vanadium, molybdenum, and zirconium. B-77 is a niobium, tungsten, vanadium, and zirconium mixture. Westinghouse says the alloys have high strength at high temperatures, and they can be forged, rolled, and sheared, often at room temperature. • Lithium-magnesium alloys containing 11% or more of lithium are being considered for use in structural parts of missiles and space vehicles, Paul D. Frost, Battelle Memorial Institute, Columbus, Ohio, told a meeting of the Mag nesium Association in New York. The alloys are about 20% lighter than magnesium. Even more important, the alloys are more ductile than mag nesium. Another advantage is the alloys' excel lent resistance to penetration by high velocity particles, making them useful in protecting space platforms and satellites from micrometeorites. OCT. 23, 1961 C&EN
49
