Loss of Radioactivity From Barium Carbonate Samples.
نویسنده
چکیده
The exchange loss of radioactivity from solid samplos of barium carbonate through the agency of carbonic acid and its ions has beon investigated under a variety of conditions. It is concluded that tho losses observed are greatly dependent upon the method of sample proparation, in particular the nature or any heat troatment which the sample materials undergo. This paper is based upon work porformed undor Contract No. W-7405-Eng.-48 with the Atomic Energy Commission in connection with the Radiation Laboratory, University of California, Berkeley. For publication in "Science ll (*) Peter E. Yankwich Department of Chemtstry e.d Ra3.iation Labo:"~3.tory} Univer8ity of California, Berkeley. * 9 January 1948 Several investigators have reported observations which lead them to conclude that barium carbonate samples containing carbon fourteen can lose rapidly rather significant fractions of their activity by exchange with atmospheric carbon dioxide throug~ the agency of moisture. In many experiments it is desirable to store countine samples for possible checkinc after weeks or months, and any rapid loss of activity by exchange or any other process 1iJould make sllch a practice hazardolls insofar as checks of exporiment3l ac,;uracy are involved; other consequences of rapid exchange loss are legion and need not be detailed here. Only two papers are availablo which report the results of purposeful investigations of this exchange phenomenon, other observations having been reported during the course of various national meetings. One of these reports (1' deals only with exchange loss when solutions of sodium bicarbonate (pH 8.8) are evaporated to dryness in a variety of atmospheres. It was observed that even the small concentration of carbon dioxide in lab._---._----------------.' " ·,1,'·,' . This papor is based on work porfor~0d under contract No. W-7405-Eng. -48 with' tho Atomio Energy COl1'1rni.ssi.on i.n connection with the Radiation Laboratory, University of va1ifornia, Berkeley. (1' W, B. Leslie, Experimental Usc of 014, Atomic Energy commiasiop, I~C ·674 ---------~---------_ ..._-----_.
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ورودعنوان ژورنال:
- Science
دوره 107 2791 شماره
صفحات -
تاریخ انتشار 1948