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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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Neutron dosimetry pro-am Operation CASTI;E. Arrangements are being made t o incorporate neutron measuring techniques developed by the Oak Ridge National Laboratory into the program of neutron radiation measurements being undertaken by t h e Naval Research Laboratory during Operation CASm. The program will be of benefit t o both groups and w i l l involve - little expense and effort. The Oak Ridge research group has made use of neptunium, uranium, and plutonium fission detectors i n studies t o determine total neutron flux. Neutron measurements' made during previous f i e l d tests have not covered the wide range of neutron energies of interest to the .biophysicists. Such data derived from these fission detector measurements would be of considerCell-free photosynthesis. Photosynthesis, t h e process by which the energy of the sun i s converted t o food stuff, has always been studied i n the intact cell. have involved use of the a l g a Chara which has very large cells from which the cytoplasm may be squeezed out, free of cell wall and cell sap. It was found that this preparation when placed i n an atomosphere of carbon 1 4 Recent experiments at Oak Ridge National Laboratory This discovery indicated that an essentially Effect of thermal'neutrons on seeds. The number of mutations produced i n barley seeds by doses of X rays and thermal neutrons has been compared with the amount of damage indicated by growth inhibition and the amount of visible chromosomal damage. A t Brookhaven National Laboratory, it was found t h a t the nutation frequency was closely cormlated with the chromosomal damzge but not correlated with growth inhibition. This f a c t . means that with thermal neutrons many more mutations will be produced for.
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a given degree of injury than for X rays; and thus thermal neutrons give great promise as a tool for genetic study. Use of phosphorus 32 in sickle-cell anemia. Sickle-cell anemia, a serious blood disorder in which red blood cells assume an abnormal sickle shape, affects approximately one in 500 Negro children in the United blood from victims of this disease not only to increase an understanding of this condition but also to obtain information concerning protein synthesis and the dynamics of phosphorus transfer in the blood. Investigators in the use of phosphorus 32 have'shown that phosphate exchanges across the red blood cell membrane are at a slower rate in sickle cells than ih normal cells. ma is significantly higher than that in normal plasma. Initial studies on phosphate transfer using metabolic inhibitors indicate the absence of a certain enzyme from the sickle-cell anemia blood. One of the most significant observations of this group on the problem is that one of the protein components of the plasma has a different mobility as determined ditional electrophoresis equipment and under varying'experimental conUnder a project with Howard University, a study is being made of This finding is being investigated further with adThis work complements other investigations in which the globin part of hemoglobin in sickle cells is found to be different from that of,norShielding studies. The problem of providing adequate shielding for personnel protection in equipment designed for radiation sources must be coupled with that of economies in operation. shielding is not an expensive factor. However, in the use of higher intensity radiations, the problem of personnel protection involves high , expenditures. This problem is being investigated under a cooperative project with the National Bureau of Standards to determine design factors of various types of equipment in which savings might be realized, and at For lower energy ranges, the same time to determine with greater accuracy the validity of former assumptions so that more reliable calculations yay be made in shielding design. The present work is concerned with the attenuation characteristics of a shield when the rays from the source enter the'shield obliquely. To a first approximation, the effective thickness of the shield has been assumed to be the length of path of the ray in the shield -that is, the more oblique the direction of incidence, the longer the path and the greater the degree of shielding. In this study it has been shown that khile oblique thickness of the barrier may be utilized in designing equipment to shield against the primary rays, the contribution of scattered radiation frgm within the shield may become appreciable. Scattered radiation increases significantly as the obliquity of the incident ray increases, because of the shorter path length for a number of the scattered rays. Data obtained from these investigations will be applicable to the design of protective shielding for personnel operating cyclotrons, Van de Graaff generators, or handling cobalt 60 and radium'sources which are used ,
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+ in research and therapy. Radiation Instruments Program Recent work under the cooperative agreement with the National Bureau of Standards for studies in the radiation instrument field includes: Study of film dosimeters. A report has been'campleted on the evaluation of the several types of film dosimeters in use at the various AEC installations. The work consisted of two parts: sensitivity, quality dependence, and maximum range of the'film badge; and show that most of these installations'are able to get a fair degree of precision in measuring and interpreting gamma and X ray radiation doses over a wide range of anergies and intensities. The survey has been important in pointing out areas where improvements may be initiated ip order to reduce inaccuracies in film dosimeter measurements. (1) Study of the Some 15 different AEC installations participated, and the findings Testing of radioactive electric cells. Tests were made of two Model E-50 electric cells of the radioactive source type manufactured by the Radiation Research Corp. of West Palm Beach, Florida. These are the first cells of this type which have appeared on the market. Preliminary results indicate that the load characteristics w e better than those claimed by the manufacturer. load is applied showed some dependence on humidity conditions. pected that electric cells of the radioactive-source type will find application in low-current devices where long storage and small battery dimensions are required. However, the voltage of the cells when no The Advisory Board on Water Decontamination met at Oak Ridge National Laboratory in October to review the current status of the Oak Ridge project on water decontamination. .provide technical advice on the project which is under the nominal supervision ofthe U. S. Public Health Service at Oak Ridge. were present from AEC, U. S. Public Health.Service, Department of Defense (AFSWP), New York State Waterworks Commission,. ,and the American Waterworks The board was set up in 1950 to The meeting included discussions of the interim progress report submitted by the Oak Ridge research group, and the following subjects were .J= covered: research on the decontamination of radioactive waters, the probQ lem of radioactivity in water courses, reconcentration of radioactivity 0 by natural agents, water decontamination, and instrumentation. The report will be revised to include further studies and later issued as anul official document for distribution by the Oak Ridge National Laboratory.pu It contains comprehensive data on decontamination studies and w i l l be ofry considerable value to all waterworks engineers in the country, in addition to having wide application in AEC operations.