JET的首期氘氚运行实验（DTE—1）——1997年JET的科研进展

１９９７年ＪＥＴ启动并圆满地完成了ＩＴＥＲ支撑计划中的首期氘氚运行实验（ＤＴＥ－１），所进行的广泛的基本系列氘氚（Ｄ－Ｔ）实验，创下了聚变功率产出（１６．１ＭＷ）、聚变能（２１．７ＭＪ）、聚变持续时间（４ＭＷ，４ｓ）和聚变Ｑ值（０．６６和瞬时地￣０．９）等新的世纪纪录。这些实验同时研究了ＩＴＥＲ的Ｄ－Ｔ物理和工艺的关键问题。本文介绍此期间内的ＪＥＴ聚变研究成果，重点是聚变等离子体性能研究和ＩＴＥＲ     

二（2—乙基己基）单（或二）硫代磷（膦）酸对示踪量镅和稀土元素的萃取

研究了二（２－乙基己基）二硫代磷酸（ＤＥＨＤＴＰ）、二（２－乙基己基）单硫代磷酸（ＤＥＨＭＴＰ）和二（２－乙基己基）单硫代膦酸（ＤＥＨＭＴＰＩ）对Ａｍ３＋、Ｎｄ３＋、Ｅｕ３＋、Ｔｍ３＋的萃取，给出了ｌｇＤ对ｐＨ和ｌｇｃ（ＨＡ）的关系图。通过比较半萃取ｐＨ值和分离系数，表明３种萃取剂对４种离子的萃取能力依次为：ＤＥＨＭＴＰＩ＞ＤＥＨＭＴＰ＞ＤＥＨＤＴＰ，但只有ＤＥＨＤＴＰ优先萃取Ａｍ３＋。对镅萃取选择性的顺序为：ＤＥＨＤＴＰ＞ＤＥＨＭＴＰＩ＞ＤＥＨＭＴＰ。此结果再次说明，Ａｍ３＋是比Ｌｎ３＋“软”一些的硬酸。     

轻粒子焦面探测器性能测量

利用ＨＩ－１３串列加速器，借测量２２ＭｅＶ质子在￣（１２）Ｃ的弹性散射质子及改变Ｑ３Ｄ磁谱仪的偶极磁场强度来研究轻粒子焦面探测器的位置ｘ，△Ｅ和Ｅ探测器的输出幅度，ＦＷＨＭ或分辨率，以及焦面探则器的效率同水平位置ｘ的关系。效率及Ｅ输出幅度同位置表现出非平直性。     

纵向型双电离室△E—E探测器系统及其在ERD分析中的应用

设计加了一套纵向型双电离室△Ｅ－Ｅ（气体－固体）探测器系统,由于采用了双电离室及电场均匀设计,得到较好的能量分辨率：利用５０．３ＭｅＶ的＾１２Ｃ在束测量,△Ｅ分辨率达３．３％,Ｅｒ分辨率达１．５％。利用该系统对新型半导体材料ＧａＡｓ、新型光电材料ＧａＮ等进行ＥＲＤ分析,得到了材料的元素深度分布谱（分辨率达５０ｎｍ）;在该系统和Ｑ３Ｄ磁谱仪配合测量中,得到深度分辨达１ｎｍ的深度分布谱。     

脉冲辐解测定茶多酚四个组分的单电子还原电位

采用脉冲电子辐解瞬态吸收光谱装置，以杜醌（ＤＱ）做对比物，在ＰＨ＝７的磷酸缓冲溶液中茶多酚４个组分：表涔食子儿茶素没食子酸酯（ＥＧＣＧ）、没食子儿茶素没食子酸酯（ＥＣＧ）表没食子儿茶素（ＥＣ）的电子还原电位值Ｅ１／７，分别为－３２１ｍＶ、－３２６ｍＶ、－３３１ｍＶ和－３３０ｍＶ，均比生物靶分子胸腺嘧啶的单电子还原电位高，表明茶多酚４个组分的亲电性能均强于ＤＮＡ碱基中亲电子性能最强的嘧啶碱基，并可作     

DHDECMP-TBP/煤油对U(Ⅵ)的萃取

ＤＨＤＥＣＭＰ－ＴＢＰ／煤油体系从１．０ｍｏｌ／Ｌ ＨＮＯ３－ＵＯ２（ＮＯ３）２介质中萃取Ｕ（Ⅵ）,除了存在ＴＢＰ和ＤＨＤＥＣＭＰ的单独萃取反应外,还存在着ＤＨＤＥＣＭＰ－ＴＢＰ的协同萃取反应。形成的萃合物分别为ＵＯ２（ＮＯ３）２．２ＴＢＰ、ＵＯ２（ＮＯ３）２．２ＤＨＥＣＭＰ和ＵＯ２（ＮＯ３）２．ＤＨＤＥＣＭＰ．ＴＢＰ。实验测定了ＴＢＰ／煤油、ＤＨＤＥＣＭＰ／煤油和ＤＨＤＥＣＭＰ－ＴＢＰ／煤国同萃     

二甲亚砜和维生素E对照剂小鼠脂质过氧化的影响

二甲亚砜（ＤＭＳＯ）和维生素Ｅ（Ｖｉｔ Ｅ）都是自由基清除剂，可抑制或阻断由自由基引发的脂质过氧化反应，减轻组织损伤和细胞的破坏。本研究应用荧光分光光度法，通过测定小鼠血清中脂质过氧化代谢产物丙二醛（ＭＤＡ）的含量来研究不同浓度的ＤＭＳＯ和维生素Ｅ对γ射线照射后小鼠的保护作用，以及两者联合应用的效果。结果表明：ＤＭＳＯ的保护作用优于Ｖｉｔ Ｅ，最大脂质过氧化抑制率（４．０Ｇｙ）分别为５５．１％和５     

RADIONUCLIDES IN NOODLES AND BREAD CONSUMED IN HONG KONG

ＲＡＤＩＯＮＵＣＬＩＤＥＳ　ＩＮ　ＮＯＯＤＬＥＳ　ＡＮＤ　ＢＲＥＡＤ　ＣＯＮＳＵＭＥＤ　ＩＮ　ＨＯＮＧ　ＫＯＮＧＫＮＹｕ（余君岳）ａｎｄＳＹＭａｏ（茅瑞恩）（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓａｎｄＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅ，ＣｉｔｙＵｎｉ...     

用于高速数据获取系统中的FERA总线驱动和存储器部件

ＦＥＲＡ总线驱动和存储器部件（ＦＤＭ）是专为ＣＶＣ而设计的单宽ＣＡＭＡＣ插件。ＦＤＭ发送控制信号到多达２２个带有ＦＥＲＡ总线功能的ＣＡＭＡＣＡＤＣ中，并自动将这些ＡＤＣ的数据收集，ＦＤＭ也可支持（联结）插在同一个ＣＡＭＡＣ机箱上的不同ＡＤＣ，插件能用两种获取模式存储来自于ＡＤＣ的数据，一种是单事例数据，一种是多事例数据，对于具有不同变换时间的ＡＤＣ，系统的数据读出同步依赖于插在同一ＣＡＭＡＣ机箱中     

MEASUREMENTS OF TOTAL CROSS SECTIONS FOR K－SHELL IONIZATION BY ELECTRON BOMBARDMENT

ＭＥＡＳＵＲＥＭＥＮＴＳＯＦＴＯＴＡＬＣＲＯＳＳＳＥＣＴＩＯＮＳＦＯＲＫ－ＳＨＥＬＬＩＯＮＩＺＡＴＩＯＮＢＹＥＬＥＣＴＲＯＮＢＯＭＢＡＲＤＭＥＮＴＬｉＪｉｎｇｗｅｎ（李景文）；ＤｏｎｇＺｈｉｑｉａｎｇ（董志强）；ＺｅｎｇＸｉａｎｔａｎｇ（曾宪堂），Ｈ...     

Hybrid direct conversion detectors for digital mammography

Hybrid pixel detector arrays that convert X-rays directly into charge signals are under development at NOVA for application to digital mammography. This technology also has wide application possibilities in other fields of radiology and in industrial imaging for applications in nondestructive evaluation and inspection. These detectors have potentially superior properties compared to either emulsion based film, which has nonlinear response to X-rays, or phosphor-based detectors in which there is an intermediate step of X-ray to light photon conversion. Potential advantages of direct conversion detectors are high quantum efficiencies (QE) of 98% or higher (for 0.3 mm thick CdZnTe detector with 20 keV X-rays), improved contrast, high sensitivity and low intrinsic noise. These factors are expected to contribute to high detective quantum efficiency (DQE). The prototype hybrid pixel detector developed has 50×50 microns pixel size, and is designed to have linear response to X-rays, and can support a dynamic range of 14 bits. Modulation Transfer Function (MTF) is measured on a l-mm silicon detector system where 10% or better modulations are obtained at 10 lp/mm spatial frequency. Preliminary DQE measurements of the same system yields a value of 55% at zero spatial frequency. Here, the authors report data of their first full size prototype readout ASIC chips hybridized with both silicon and CdZnTe detector arrays and present initial MTF and DQE measurement results as well as some test images     

Monte-Carlo simulation for determining SNR and DQE of linear array plastic scintillating fiber

1 Introduction Radiation imaging detector can be designed ineither one or two dimension. Each kind of them has itsown advantages and disadvantages. One of the advan-tages of linear array detectors is its less effects ofscattering and crosstalk between pixels. These twoeffects are very important to make an image with highor low quality. This is the main reason for choosinglinear array in our research. So these effects can be shown in contrast andspatial resolution, which are crucial…     

Optimization of decay kinetics of YAG:Ce single crystal scintillators for S(T)EM electron detectors

To enhance the detective quantum efficiency (DQE) of scintillation electron detectors for scanning electron microscopes or scanning transmission electron microscopes (S(T)EM), the cathodoluminescence (CL) decay kinetics of YAG:Ce single crystal scintillators is studied in this paper. Some possibilities for reductions of decay time and afterglow of the mentioned scintillators are presented. The pulse mode utilizing a blanking system and 10 keV electrons for the excitation and a sampling oscilloscope for the CL detection were used for the measurement of decay characteristics. The CL decay characteristics of YAG:Ce single crystals of different Ce concentrations, pulled by the Czochralski method and cleaned and annealed under specific conditions, were measured in dependence on excitation pulse duration and on the specimen temperature. To interpret the presented results, a kinetic model of cathodoluminescence of the YAG:Ce single crystals was created. The effects of quenching impurities and of defect centers in YAG:Ce were specified.     

A new linear array detector for high resolution and low dose digital radiography

At the Department of Physics of the University of Bologna a new intensified linear array detector is under development. The core of the system is a digital intensified CCD camera, the electron bombarded charge coupled device (EBCCD). The main innovation is a coherent rectangular-to-linear fiber optics adapter coupling the 1 in. diameter photocathode of the camera with a linear 129 mm × 1.45 mm strip of Gd₂O₂S:Tb. In this way a high spatial resolution over an extended length is obtained. The detector works as an X-ray scanner by means of a high-precision translation mechanical device to inspect a 13 cm × 18 cm area. A complete characterisation of the system has been made in terms of linearity, dynamic range, modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE). At last, radiographic tests on a set of samples have been made and will be presented.     

热中子照相成像系统的研制

成像系统是中子照相装置的关键组件之一.利用Gd和In金属研制了胶片静态照相转换屏,采用6LiF ZnS为转换材料,增强型CCD和制冷型CCD相结合,研制了CCD在线中子成像系统.     

基于LaBr3(Ce)晶体耦合SiPM阵列的可变角分辨率伽玛相机的设计与研制

编码孔径成像技术由于探测效率高、信噪比高、角分辨率好、成像质量稳定可靠等优点而广泛应用于核安全、核设施的去污及退役的测量、核医学等领域。建立通过改变编码准直器和探测器之间距离进而实现可变角分辨的伽玛成像系统。整个成像系统主要由编码准直器、位置灵敏探测(position sensitive detector, PSD)、数据采集卡以及图像重建系统组成。该成像系统的编码准直器采用修正均匀冗余阵列(modified uniformly redundant array, MURA)编码方式,为了保障对较高能量射线的探测能力,编码准直器的材料采用含钨量90%的钨铜合金,PSD通过LaBr₃(Ce)晶体耦合SiPM阵列组成,重建算法采用的是直接互卷积算法,快速高效。测试结果显示,整个位置灵敏探测器的平均能量分辨率为4.96%(662 keV);该辐射成像系统可以准确地对Am-241、Cs-137、Co-60进行清晰成像,并通过改变编码准直器和探测器之间的距离成功分辨出两个Cs-137点源的位置。     

X射线编码孔成像技术在近地太空核爆探测中的应用

根据X射线编码孔成像的原理,搭建了地面模拟成像系统,在此基础上建立了编码孔成像技术探测近地太空核爆当量和方位的理论计算方法,获得了系统响应（灰度）与X射线强度、重建图像质心位置与X射线入射角度之间的关系,并开展了核爆当量和方位的模拟探测实验,对实验数据和理论计算数据进行了对比和分析。结果表明,理论计算结果与实验结果吻合较好,验证了采用X射线编码孔成像技术探测近地太空核爆的可行性,同时证明X射线编码孔成像具有较多针孔成像更高的探测灵敏度、信噪比和抗干扰能力。     

X射线成像系统的非线性特性

通过理论分析和实验研究，探讨了X射线成像系统的非线性特性及其成因，这对于提高X射线成影像的质量具有重要意义。     

Two-dimensional vacuum ultraviolet images in different MHD events on the EAST tokamak

A high-speed vacuum ultraviolet (VUV) imaging telescope system has been developed to measure the edge plasma emission (including the pedestal region) in the Experimental Advanced Superconducting Tokamak (EAST).The key optics of the high-speed VUV imaging system consists of three parts:an inverse Schwarzschild-type telescope,a micro-channel plate (MCP) and a visible imaging high-speed camera.The VUV imaging system has been operated routinely in the 2016 EAST experiment campaign.The dynamics of the two-dimensional (2D) images of magnetohydrodynamic (MHD) instabilities,such as edge localized modes (ELMs),tearing-like modes and disruptions,have been observed using this system.The related VUV images are presented in this paper,and it indicates the VUV imaging system is a potential tool which can be applied successfully in various plasma conditions.     

Detector Concept for OPET-A Combined PET and Optical Imaging System

The design of an imaging system capable of detecting both high-energy γ-rays and optical wavelength photons is underway at the UCLA Crump Institute for Molecular Imaging. This system, which we call optical PET (OPET), will be capable of non-invasively and repeatedly imaging small animal models in vivo for the presence of PET and optical signals. In this study, we describe the physical principles behind the operation of the OPET imaging system and discuss the design concept for one of the detector modules. Additionally, we demonstrate the operation of an initial prototype detector module for simultaneous detection and imaging of annihilation radiation and single optical photons emanating from separate sources. These results indicate that the construction of an imaging system based on this detector technology is feasible.