RESEARCH
Vanillin Pharmaceutical
have given polymers with new, improved characteristics. The work of "W7
A new
Only one amount of lead discharged is only a fraction of that present in the gasoline consumed." The accumulation of deposited lead, he states, is largely expelled during high-speed driving on the open road. Thus the exhaust piping and muffler are capable of again trapping lead in city driving. Ethyl's study of lead emission from automobiles was undertaken because of current interest in the minor constituents of engine exhaust gas, Hirschler says, and because no other work on the subject has been reported recently. In his report before the Division of Petroleum Chemistry, Hirschler said electrostatic precipitators were used to separate lead particles from the exhaust gases of both six-cylinder and eightcylinder motors. Particle-size studies indicate that only one half to three quarters of the lead emitted in city driving is small enough to remain suspended in the air. This fact, and the lower lead emission during light-load operation, account for low concentrations of lead observed in recent studies of urban atmospheres. It is difficult to relate atmospheric lead analysis directly to amounts of lead exhausted by automobiles, Hirschler claims, because other industrial and natural sources also contribute lead to the atmosphere. "Our results indicate that even lower lead emission in cities may result from current trends in engine design," Hirschler says. The use of dual-exhaust systems and multiple mufflers is increasing; they will trap more lead during light-load operation and release it as coarser particles in open country driving. A n d the use of larger engines, "which operate at lighter loads in city driving, will also tend to reduce lead emission in congested areas. 4778
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Vienna. H e attempted to produce pharmacologically active substances from vanillin, the most important degradation product of lignin. Kratzl and his coworkers synthesized amides from vanillic acid and its derivatives. One of these amides, the vanillic acid diethyl amide, is of definite therapeutical use for blood pressure arid respiration, Kratzl told the Division of Cellulose Chemistry. Called Vandid, it can be given to stimulate respiration and blood pressure simultaneously, according to Kratzl. The compound has an extremely strong effect on respiration; it is claimed to be 15 times as active as Niketamid (Coramine) and almost four times as active as Metrazol (Cardiazol). Also, according to Kratzl, Vandid has a more stimulating effect on blood pressure than either Niketamid or Metrazol. In addition, Vandid is said to be 20 times more effective for blood pressure than the diethyl amide of protocatechuic acid and 15 times more than that of veratric acid. Clinically, Kratzl says that Vandid has been given successfully to treat patients poisoned from barbiturates, other hypnotics, and carbon monoxide gas. The reason for this, according t o Kratzl, is that Vandid has a strong wakening power in addition to raising blood pressure and respiratory volumes. Another application, for Vandid, according to Kratzl, is in pediatrics: It is used in cases of "cyanosis" of premature births and general circulation failure. Kratzl also synthesized other compounds from vanillin. However, none of the others were of therapeutical or clinical use.
Copolymers by Irradiation Gamma-ray irradiation grafting of monomer to polymer produces special properties in films
Grafting ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ H ene and the comamounts of styrene to polytetrafluoroethylene (Teflon)
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the Polytechnic Institute of Brooklyn and Bropkhaven National Laboratory with these and other combinations emphasize the important role of monomer diffusion into polymer films in the "grafting" process mechanism. Chen in his discussion of mechanisms of the irradiation grafting process and applications before the Division of Polymer Chemistry's symposium on block and graft polymers, dealt with four factors that influence efficiency of grafting for any given polymer-monomer combination: • Temperature as it defines reaction rates and solubility of monomer in polymer films. • Gamma-ray irradiation dose rate. • Diffusion rate of monomer into polymer as dependent upon film thickness. • Grafting Applications. Chen and his collaborators prepared graft copolymer films by gamma-ray irradiation aiming to improve base film limitations while retaining desirable properties. Polyethylene containing various amounts of vinyl carbazole produced films with better softening temperature characteristics and insulation resistance than polyethylene alone. Polyethylene containing grafted styrenesulfonic acid produces a cation exchange membrane with high mechanical strength capable of being repeatedly dried and rewetted without loss of strength. Adding between 1 and 10% styrene to polytetrafluoroethylene (Teflon) significantly increases adhesion characteristics, Chen says. A graft copolymer made b y Chen contains large amounts (20% or more) of acrylonitrile in polydimethyl-siloxane rubber to give doubled resistance to toluene and heptane. Chen emphasizes that before final evaluating the role of monomer diffusion, much more investigation is needed on increased solubility of monomer with grafting, initiation and termination kinetics, and effects of a wider range of film thickness. ^r *v -w ^Cane or refined sugar, its all the same to baby pigs. In many experiments involving over 1000 pigs, varying from one to eight weeks in age, the animals showed a preference for a pelleted starter ration containing 15% sugar. In meal form, 20% sugar is needed for best palatability. But, in either case, the cane or refined sugar would satisfy the pig. D . B. Hudman, C . J. Lewis, P. A. Hartmaa, G. C. Ashton, & D . V. Catron, Iowa State College Carbohydrate Division
