The Chemical World This W e e k
NOVEMBER
21, i960
5S£S£ CONCENTRATES • The c o m p l e t e amino acid sequence of the protein in t o b a c c o mosaic virus (TMV) has been worked out at University of California, Berkeley [Proc. Natl Acad, Sci. U.S., 46, 1463 ( I 9 6 0 ) ] . T h e research team there is headed by Dr. Wendell M. Stanley and Dr. Heinz L. FraenkelConrat. A TMV particle contains 9 5 % protein, 5 % ribonucleic acid. The protein portion is made up of about 2200 seemingly identical protein molecules, each one having a molecular weight of close to 18,000. This is the third (and largest) protein whose amino acid residue sequence has been determined. The other two: insulin and ribonuclease. Knowing the sequence of TMV's 158 amino acids should enable tracing mutation effects in detail. •
A new metallic compound w i t h magnetic properties which a r e turned on by h e a t has
been found by research workers at Du Pont. A compound of manganese and antimony with varying amounts of chromium, the material develops strong magnetism when heated to a transition temperature, Dr. W. H. Cloud and Dr. H. S. Jarrett told the sixth annual Conference on Magnetism, held in New York. The transition temperature depends on the amount of chromium present, can be between near 0° K. and 100° C. • Unexpected results of s p a c e exposure on a bread mold, Neurostora crassa, makes a bioassay of space necessary before sending man, according to Dr. A. Gib DeBusk of Florida State University, Tallahassee. Samples of the mold "hitchhiked" on the Argo D-8 rocket shot which rose 1180 miles and spent 26 minutes in the Van Allen belt. Tests designed to detect mutants showed a large number of physiologically damaged nonmutants. These regained their original activity if jogged by a complex diet. Although the physical and biological measurements are m a d e on different shots, fluctuation in the Van Allen belt intensity is much too small to account for the observed effect. Dr. DeBusk believes the effect is caused by synergistic action of all factors, even weightlessness. • A plasma-jet d e v i c e for s p a c e c r a f t has undergone continuous firings for 18.5 hours at General Electrie's missile and space vehicle department. The Repetitively Pulsed Plasma Accelerator ( R E P P A C I ) reached nearly 4 million individual pulses at a 3000 per minute rate. The test run could have stabilized a space vehicle for about two years, GE estimates. Pulsing is done
by electromechanically injecting a measured amount of gas (like argon, helium, nitrogen, or metal vapors) into the REPPAC I "gun" while 2500 watts discharge in a high current circuit. Resulting electromagnetic field ionizes the gas, lets it conduct current between electrodes placed at opposite ends of REPPAC Vs T-shaped tube. This gives a plasma jet which is accelerated magnetically into a vacuum chamber to produce thrust; the test run produced about 0.1 ounce of thrust. • Universal Oil Products" Purzaust meets or ex* c e e d s standards considered for California Air Pollution Control Laws, UOP's R. E. Sutherland told the California State Motor Vehicle Pollution Control Board. If the Purzaust catalytic muffler is used on all cars and replaced every two years, hydrocarbon emission from auto exhausts can be cut 8 0 % , carbon monoxide 7 6 % , he says. Proposed standards call for an 8 0 % cut in hydrocarbons, 60 % in carbon monoxide. Estimated cost of Purzaust is $50 more than for a conventional muffler. It would do away with the need for costly and complex inspection, Mr. Sutherland says. California is now trying to set up criteria for pollution control devices and eventually approve a control device. • A new idea in light buibs would use the dissociation energy of hydrogen to achieve a theoretical efficiency of 60 to 70 lumens per watt (about five times that of ordinary incandescent b u l b s ) . A lamp based on the principle is still in the research stage, but Dura-Test Corp., which has a patent on such a lamp (U.S. 2,920,222), hopes eventually to crash the consumer market. In the proposed lamp, hydrogen molecules in the bulb dissociate into atoms at a hot tungsten filament; the atoms then recombine on a phosphorcoated bulb wall to release large quantities of energy. •
A facsimile device capable of printing a square f o o t of information per second and
transmitting it between two distant points has been developed by Hogan Facsimile Division of TELautograph Corp. Called the remote document retriever, the unit uses a flat bed continuous multiple stylus facsimile recorder. The recorder remotely reproduces the scanned material on electronic recording paper. U.S. Navy's Bureau of Ships has installed the prototype of the retriever in an attempt to solve its world-wide information retrieval problems. NOV.
2 1,
1960
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