Abstracts of Bell System Technical Papers 

 Not Published in this Journal 



Bennett, W.^ 



Telephone-System Applications of Recorded Machine Announce- 

 ments, A.I.E.E., Trans., Commiin. et Electr(3nics 8, pp. 478-483, 

 Sept., 1953. 



BiELiNG, D., see D. Edelson. 



Biggs, B. S.^ and W. L. Hawkins^ 



Oxidative Aging of Polyethylene, Modern Plastics, 31, pp. 121-122, 

 124+, Sept., 1953 (Monograph 2155). 



Thermal oxidation of polyethylene follows the pattern set by lower homo- 

 logues such as paraflinic waxes and oils. It is an autocatalj'tic free radical 

 chain reaction and is subject to inhibition b}' typical antioxidants. The rate 

 of degradation in the dark at room temperatures is found to be extremely 

 low. Photo-oxidation of polj'ethjdene is rapid in contrast with that of sat- 

 urated low molecular weight aliphatic l\ydrocarbons. Furthermore, anti- 

 oxidants are of little benefit in protecting against exposure to light. Opaque 

 pigments are of great value in reducing the effects of light, finely divided 

 carljon black being particularly effective. By proper compounding polj'- 

 ethylene can be made to last many years outdoors. 



BozoRTH, R. M., see H. J. Williams. 



Brown, W. L.^ 



n-Type Surface Conductivity on p-Type Germanium, Phys. Rev., 

 91, pp. 518-527, Aug. 1, 1953 (Monograph 2173). 



* Certain of these papers are available as Bell System Monographs and may be 

 obtained on request to the publication;Department, Bell Telephone Laboi'atories, 

 Inc., 463 West Street, New York 14, N. Y. For papers available in this form, the 

 monograph number is given in parentheses following the date of publication, and 

 this number should be given in all requests. 



1 Bell Telephone Laboratories. 



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