快中子活化法对声空化核效应的验证  

Verification of Nuclear Effect of Acoustic Cavitation Using Fast Neutron Activation Method

作　　者：李欣年[1] 冯涛[1] 方晓明[1] 钱梦騄[2] 程茜[2] 

机构地区：[1]上海大学射线应用研究所,上海201800 [2]同济大学声学研究所,上海200092

出　　处：《原子能科学技术》2014年第6期1111-1119,共9页Atomic Energy Science and Technology

基　　金：国家自然科学基金资助项目(10974145)

摘　　要：采用纯铜作为阈探测器检测声致核聚变产生的14MeV中子。根据14MeV中子与Cu的核反应,选择合适的放射性核素及其特征γ峰作为测量依据。中子辐照时间为50min,经30min和198min冷却,NaI探测器分别测量了超声和非超声下活化铜片的511keV特征γ峰计数,测量结果显示,采用短冷却时间可测得62 Cu的511keVγ特征峰,γ峰净面积计数增量ΔC均为正值,具有统计意义,在声空化条件下核反应液体中D-T反应产生的14MeV中子发生率大于在非声空化条件下的;采用长冷却时间可测得64 Cu的511keVγ特征峰,ΔC均为正值,具有统计意义,在声空化条件下核反应液体中D-D反应产生的2.45MeV中子发生率大于在非声空化条件下的。由此验证了声空化核效应(NEAC),并初步分析了中子成核声空化核效应的机制。14 MeV neutrons originated in acoustic cavitation fusion were determined using copper threshold detector .According to the nuclear reaction of 14 MeV neutrons with copper ,the characteristic γ peaks of some radioactive nuclides were measured and the activation parameters of Cu were optimized . With neutron irradiation time of 50 min ,511 keV characteristic γpeak counts of activated copper pieces with or without ultrasonic field after 30 min and 198 min were respectively determined by NaI detector . Measurement results show that the characteristic γ peak counts of 62 Cu and 64 Cu can be respectively determined after 30 min and 198 min .511 keV characteristic γ peak net count increments are positive values and statistical significance , w hich indicates that 14 MeV and 2.45 MeV neutron generation rates originated in fusion with ultrasound are greater than that without ultrasound in nuclear reaction liquid .These results verify the＆amp;nbsp;nuclear effect of acoustic cavitation （NEAC） .The mechanism of NEAC nucleated by neutrons was proposed initially .

关 键 词：快中子活化 阈探测器 声空化核效应 空化泡 

分 类 号：TL81[核科学技术—核技术及应用]