Results 81 to 90 of about 651 (153)
Shuitu Baochi Xuebao, 2017 为了揭示冀西北坝上干旱区三北防护林主要树种北京杨的耗水特征，采用热扩散式茎流仪研究了不同健康等级北京杨的树干液流特征，同时分析了气象因素和个体生长状态对树干液流的响应。结果表明：北京杨树干边材液流无论是晴天还是阴天均表现出明显的昼夜变化规律，晴天启动早，停止晚；夜间也存在树干液流，健康杨树个体夜间耗水贡献率为2.50%～5.60%，不健康单株夜间耗水贡献率高达8.37%～21.20%。不同健康等级杨树个体水分消耗在0.01水平存在差异，不健康个体日均耗水量为（22.95±5.99）L，仅为健康单株的27.
马长明, 马玉洁, 程月明
doaj
WEAPONS BASED ON NEW PHYSICAL PRINCIPLES:
International Journal of Law in Changing WorldIn today’s rapidly shifting geopolitical landscape, there is growing concern about weapons based on new physical principles—technologies that remain largely unknown to the public but may pose significantly greater threats than conventional arms.
Elona Abasalieva
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Evolving Characters of Fukushima-derived 134,137Cs in Marine Environment: Decadal Analysis of Most Polluted Port near FDNPP [PDF]
A large amount of artificial radionuclides have been released into the ocean, contributing to serious nuclear pollution in marine environment, and arising public concerns and worry around the world. The Fukushima-derived artificial radionuclides can also
LIN Wuhui1, , ZHANG Yibang2, 3, DU Jinqiu3, LUO Zhu4, CAO Shaofei5, TUO Fei6
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He jishu硼中子俘获治疗（Boron Neutron Capture Therapy，BNCT）是一种新兴的放射治疗技术，而呼吸运动是BNCT治疗肺癌影响剂量准确度的关键问题。为了量化呼吸运动对BNCT治疗肺癌的剂量学影响，采用蒙特卡罗模拟方法构建肺癌治疗中肿瘤及器官随呼吸运动时空变化的动态模型，并开展BNCT蒙特卡罗剂量计算。本文基于多功能数智化蒙特卡罗程序平台（Multi-function and Generalized Intelligent Code-bench based on Monte Carlo ...
朱 琳 +9 more
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Positioning technique of coded aperture radiation imaging [PDF]
With the widespread application of nuclear technology and radiation protection, the demand for radioactive sources imaging is increasing. As a high-precision imaging and positioning device for radioactive sources, the coded aperture imaging positioning ...
ANG Wensheng +4 more
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Dianci bileiqi, 2016 由雷电引起的浪涌电压和电流是造成电子设备失效甚至损坏的主要因素。雷电辐射电磁场的水平电场分量在雷电瞬态过电压的研究计算中占据重要位置,然而目前针对雷电辐射水平电场的近似算法均是将地表假设成光滑地表,但现实中的地表常常存在高低起伏的特征。针对上述问题,基于Cooray-Rubinstein算法（简称C-R算法）提出了一种适用于二维分形粗糙地表的雷电水平场计算的新算法,并利用三维时域有限差分方法对其适用范围和精度进行了检验。结果表明:相比于光滑地表,粗糙地表对雷电水平电场的衰减不容忽视 ...
刘涛, 李东帅, 张其林
doaj
Crosstalk interference and correction methods for low background gas-flow proportional counter [PDF]
The crosstalk phenomenon and its influence in the determination of gross α and β radioactivity when using a low background gas-flow proportional counter as a measuring instrument was examined in this paper. The crosstalk ratio between α and β channel was
GUO Xiaomin +4 more
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Dianci bileiqi, 2018 针对强风导致紧凑型输电线路各相导线间间隙距离减小而发生的闪络情况,分别采用了辐射交联聚烯烃材料的母排热缩管和优质硅橡胶材料的卡扣式绝缘护套管,提出了将其安装在输电线路上来进一步增大输电线路相间放电距离的方法。建立了模拟输电线路风偏放电试验的物理模型,在不同间距情况下,对裸电线和裸导线分别双根包覆绝缘护套进行导线间空气间隙工频击穿试验。试验结果表明:裸导线空气间隙工频击穿电压与间隙距离近似呈线性关系,这与棒-棒间隙相似。裸导线双根包覆不同绝缘护套后,击穿电压提升都很明显,但卡扣式硅橡胶管安装更为方便 ...
彭永晶 +5 more
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Evaluation on Adsorption Separation of Low Concentration Xe and Kr by Activated Carbon Through Static and Dynamic Methods [PDF]
Radioactive Xe isotopes are located at the heavy mass peaks of the fission mass distribution curves of 235U and 239Pu, with the characteristics of high fission yields and moderate half-life times, which have important application value in environmental ...
Bin CHEN +6 more
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