共查询到14条相似文献,搜索用时 46 毫秒
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用阈探测器活化法测量了每个核子动能(简称单核能)为50MeV^18O离子轰击厚靶(Be、Cu、Au)时出射中子的能量分布、注量率分布和中子角分布,得到了^18O离子的中子产额、前向中子发射率和中子剂量当量率分布的数据。并与国外报道的单核能在20MeV以下的低能重离子轰击厚靶研究中得到的中子剂量学参数进行了比较和分析。 相似文献
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A radiochemical procedure used to separate and purify trace concentration thorium produced in heavy ion reaction with uranium targets is presented.The procedure can rapidly yield thorium fraction suitable for gamma-ray spectroscopy studies.The resultant gamma-ray spectra showed that Th was isolated from a large number of elements produced in the reaction,and there were only a few contaminating activities of isotopes of Sc,Cd,In,etc.The decontamination factors for the main reaction products are given. 相似文献
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The activities of protactinium were produced by the multi-nucleon transfer reactions in bombardment of the natural uranium with 60 MeV/nucleon ^18O ions.A simple,relatively fast radiochemical procedure was used for extraction separation of protactinium from the uranium and a variety of reaction products using 1-phenyl-3-methyl-4-benzyoyl-5-pyrazolone and tri-sio-octylamine as extractants.The γ ray spectrum of the separated protactinium fractions showed that the protactinium could be separated from all of the amin impurity elements.The decontamination factors of the uranium and the main reacion products produced in the reaction are given. 相似文献
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研究重离子辐照小鼠头部对脾脏细胞周期分布的影响,为重离子放射治疗癌症和太空防护提供基础数据。80MeV/u能量的^12C^6+对BALB/c小鼠头部给以0、0.5、1、2、4、10Gy的照射,用流式细胞仪测脾脏细胞周期分布。重离子辐照后36h,小鼠脾脏细胞S期细胞随着辐照剂量的增加显著减少(p〈0.05);0.5Gy组、4Gy组和10Gy组出现G0/G0期阻滞明显阻滞(p〈0.05),1Gy组和2Gy组无显著变化(p〉0.05);0.5Gy组G2/M期细胞显著减少(p〈0.01),其它剂量组明显阻滞(p〈0.05)。重离子辐照小鼠头部对小鼠脾脏细胞周期分布有明显影响。 相似文献
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I. Strašík E. Mustafin R. Hinca D. Schardt A. Golubev B. Sharkov G. Fehrenbacher H. Iwase G. Mustafina 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(15):3443-3452
As a preparatory work for constructing the FAIR facility at GSI, samples of stainless steel and copper were irradiated by 950 MeV/u 238U ions and depth-profiles of residual activity were measured by gamma-ray spectroscopy. The isotopes with dominating contribution to the residual activity were identified and their contributions were quantified. In contrast to the previous study performed at lower energies, the activities could no longer be determined from the full-assembly target measurements. Depth-profiling of residual activity of all identified isotopes had to be completed by measurements of individual target foils. The activity contributions were then obtained by integration of the depth-profiles. 相似文献
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R. Bimbot A. Khoumri A. Fahli S. Barbey T. Benfoughal M. Mirea A. Hachem G. Fares R. Anne H. Delagrange C. Tribouillard Y. Georget J. C. Foy 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2000,170(3-4):329-335
The stopping powers of six gaseous media have been measured for incident 40 MeV/u 125Te heavy ions. The energy losses of ions in various “thicknesses” of gas have been accurately determined. The gases were confined in a cell. The amount of matter traversed by the ions was determined from temperature and pressure measurements. The beam energy before and after slowing down were measured using the LISE magnetic spectrometer at GANIL. These experimental gas stopping powers are lower by about 10% than the corresponding tabulated values for solid media. This means that the gas–solid effect is still significant at 40 MeV/u for Te ions. The projectile effective charges derived from these measurements depend on the target atomic number, thus confirming the trend observed in previous experiments performed with lighter ions or at lower energies. 相似文献