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991.
提出了一种在多片Si-PIN探测器中间用2mm厚的聚乙烯作为灵敏度增强介质,采用加法电路模式进行信号输出的组合式新型DT聚变中子(14MeV)探测技术原理. 这种组合的主要特点有: 1)大幅度提高了Si-PIN探测器的中子灵敏度和测量统计性; 2)提高了探测器的n/γ分辨本领; 3)在实现多个探测器信号相加的同时,组合探测器相对于单片探测器时间响应没有明显改变. 从实验及理论上对组合探测器的14MeV中子及1.25MeV γ灵敏度、n/γ分辨,时间特性和测量统计性进行了研究. 相似文献
992.
This paper describes a newly designed gamma pulse detector of current mode that uses the scattered electron method. Tungsten is used as the scattering target, an organic thin film scintillator ST401 is used to collect the scattered electrons. The spatial distribution of the electronic energy-flux density is studied by using the MCNP code. The optimization of the target and the thickness of the scintillator are also discussed. The results indicate that the energy response is relatively flat in the range of 0.4 to 5 MeV. 相似文献
993.
In this letter, poly(vinylidene difluoride) (PVDF)/(Y0.97Eu0.03)2O3 rare-earth nanocomposites were prepared by a simple co-precipitation method, and their morphology, structure, and optical properties were investigated. The scanning electron microscope (SEM) images showed that the (Y0.97Eu0.03)2O3 rare-earth nanoparticles formed 50 nm - 2μm aggregates in PVDF matrices. X-ray diffraction (XRD) curves indicated the incorporation and structure preserving of (Y0.97Eu0.03)2O3 nanoparticles in PVDF matrices. Photoluminescence (PL) spectra of the nanocomposite showed a characteristic red light emission at 612 nm, which was attributed to the intrinsic emission of (Y0.97Eu0.03)2O3 nanoparticles. Optical band gap (Eg) of the nanocomposite exhibited a decreasing trend with the increase of (Y0.97Eu0.03)2O3 content in PVDF matrices within the experimental dosage range. 相似文献
994.
In this letter, poly(vinylidene difluoride) (PVDF)/(Y0.97Eu0.03)2O3 rare-earth nanocomposites were prepared by a simple co-precipitation method, and their morphology, structure, and optical properties were investigated. The scanning electron microscope (SEM) images showed that the (Y0.97Eu0.03)2O3 rare- earth nanoparticles formed 50 nm - 2 μm aggregates in PVDF matrices. X-ray diffraction (XRD) curves indicated the incorporation and structure preserving of (Y0.97Eu0.03)2O3 nanoparticles in PVDF matrices. Photoluminescence (PL) spectra of the nanocomposite showed a characteristic red light emission at 612 nm, which was attributed to the intrinsic emission of (Y0.97Eu0.03)2O3 nanoparticles. Optical band gap (Eg) of the nanocomposite exhibited a decreasing trend with the increase of (Y0.97Eu0.03)2O3 content in PVDF matrices within the experimental dosage range. 相似文献
995.
SiHua Ouyang ChunChang Wang GuoZhen Liu Meng He KuiJuan Jin ZhiMin Dang HuiBin Lü 《中国科学G辑(英文版)》2008,51(3):232-236
We report here studies on the influence of oxygen pressure on the electroresistance behavior of La0.9Sr0.1MnO3 thin films fabricated by laser molecular beam epitaxy. It was found that the film deposited at lower oxygen pressure shows
larger c-axis parameter, higher resistance, and more distinct electroresistance. These results reveal that the electroresistance of
manganite thin films can be tuned by the conditions of film fabrication.
Supported by the National Natural Science Foundation of China (Grant No. 10334070) and the National Key Basic Research Program
of China (Grant No. 2004CB619004) 相似文献
996.
设计了SiO2与电极间加入ZnS的复合加速层结构,进一步说明靠电子注入的增强来扩大初电子源.同时,在电子发生倍增前后的电压下,对比了单层和夹层结构的不同加速层的发光性能.得到在低压直流下单侧复合加速层器件的发光优于单层SiO2加速层器件而劣于单层ZnS器件;在高压交流下复合加速层表现出明显的优势,在复合加速层中,ZnS不仅对电子有加速作用,而且对增强电子注入贡献很大,同时ZnS和SiO2/ZnS界面还提供了初电子源.另外,与SiO
关键词:
电致发光
复合加速层
过热电子
固态阴极射线 相似文献
997.
利用全相对论多组态:Dirac-Fock方法系统地计算了高离化类铍离子的磁四极M2 2s2 1S0-2s2p3P2 (Z=10-103)自旋禁戒跃迁的能级间隔、跃迁概率和振子强度,计算中考虑了重要核的有限体积效应,Breit修正和QED修正,所得结果和最近的实验数据以及理论值进行了比较,结果表明:高原子序数的高电荷离子(Z≥70)磁四极M2自旋禁戒跃迁几乎可以和中性原子的光学允许跃迁相比拟,不仅在天体等离子体中,在ICF和MCF高温激光等离子体中,磁四极自旋禁戒跃迁和其他自旋禁戒跃迁(磁偶极、电四极)一样不容忽视,在双电子复合、不透明度、自由程等理论计算中应该考虑其影响. 相似文献
998.
Ouyang X Tsai TY Chen DH Huang QJ Cheng WH Clearfield A 《Chemical communications (Cambridge, England)》2003,(7):886-887
The solvothermal reaction of elemental zinc with sulfur in ethylenediamine (en) as solvent yields [ZnS-0.5(NH2CH2CH2NH2)], 1, an unprecedented ethylenediamine pillared ZnS layered compound, containing two dimensional (2-D) boat-type 6-membered rings, which was characterized by ab initio structure solution from powder diffraction data (SDPD). 相似文献
999.
1000.
Ouyang Qin Wang Yanfei Huang Jing Wang Heng Zhu Lingling Hu Jing He Liu Huang Qing 《Journal of Thermal Analysis and Calorimetry》2022,147(21):11759-11767
Journal of Thermal Analysis and Calorimetry - The degradation of SiCxOy phase is a crucial step during the conversion of polyaluminocarbosilane-derived amorphous Si-Al-C-O fiber into highly... 相似文献