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A study was made of the conformational and thermodynamic properties of chlorinated stereoregular (∼ 96% cis-1,4-configuration) polyisoprene (CSKI). The report is based on the results of investigations of the light scattering and viscosity of a series of polymer-homologues in different solvents. Correlations of the Mark-Kuhn-Houwink type were found for all the polymer-solvent systems investigated. Light is thrown on the effect of the type of solvent on the conformation and flexibility of the CSKI macromolecules in the “unperturbed” state. In a strongly polar medium (dichloroethane-methanol) the Gaussian structure of the molecular coils is slightly distorted.

We p r e s e n t s o m e e x a m p l e s of l o c a l l y s o l v a b l e s e m i s i m p l e L i e a l g e b r a s tha t a r e not RN* a l g e b r a s , a s w e l l a s e x a m p l e s of l o c a l l y n i lpo ten t RN* L i e a l g e b r a s wi th n e i t h e r Engel e l e m e n t s , nor (of cou r se ) a c c e s s i b l e e l e m e n t s (for de f i n i t i ons , cf. fo r e x a m p l e , [1]-[3]). Ana logous e x a m p l e s w e r e c o n s t r u c t e d for g r o u p s in [4]-[10]. L o c a l l y n i l po t en t RN* L i e a l g e b r a s wi th no Enge l e l e m e n t s w e r e c o n s t r u c t e d in [11]. In th i s p a p e r we w i l l u se a d i f f e r e n t c o n s t r u c t i o n to c r e a t e L i e a l g e b r a s wi th the d e s i r e d p r o p e r t i e s . The b a s e f i e ld 9 wi l l be a r b i t r a r y . We s h a l l show that if a l o c a l l y n i lpo ten t L i e a l g e b r a has a l o c a l l y n i lpo ten t enve lop ing a l g e b r a , then e v e r y e l e m e n t in the o r i g i n a l a l g e b r a i s an Engel e l emen t .

We synthesized a number of saturated and unsaturated compounds containing the nitrodifluoromethyl group.

The reaction of perfluoroketones with alkylvinyl ethers leads to 2-alkoxy-4,4-bis(perfluoroalkyl) oxethanes, subsequent isomerization of which yieldedβ-alkoxyvinyl-bis(perfluoroalkyl)carbinols.

Fluoroketones (I) and their imines (III) enter into a noncatalyzed addition reaction with benzonitrile oxide.

A diffusion-mask technique has been developed to make germanium planar diodes and PNP transistors. This preferential masking is effective for various P and N type dopants at different concentration levels and diffusion lengths. A comparison is made of all the characteristics of the planar and its equivalent mesa structure. All the surface dependent parameters, such as diode reverse current, surface recombination velocity, have shown improvement over mesa units. Also, a very narrow distribution of these parameters has been observed. Units fabricated by this technique have higher reliability at ambient as well as elevated temperatures over equivalent mesa units. Life stability of the device is very satisfactory.