最新刊期
      卷 43 ， 期 8 ， 2020

        SPECIAL SECTION ON THE 11TH NATIONAL CONFERENCE ON NEW AND RESEARCH REACTORS (PART III)

      • “西安交通大学研发的SARAX软件包，为铅冷小堆堆芯设计提供中子学计算分析，满足安全要求。”
        XIAO Huiwen,LI Xiang,LIU Guoming,ZHENG Youqi
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080001
        摘要：BackgroundAs the coolant of the reactor, lead and lead-based alloy has excellent thermal properties. Developing lead cooled reactor attracts has been practicing with major investment in many countries, such as European union countries, Russia, Korea, Japan, China and so on.PurposeThis study aims at the preliminary design of modularized lead cooled small reactor.MethodsFirst of all, the neutron transport, depletion, reaction coefficient and kinetic parameters were calculated by using SARAX, a fast reactor neutronics calculation software developed by Xi'an Jiaotong University. High enrichment fuel was adopt for compact light-weight, and two different enrichment fuel was chosen to flat the power distribution. Two group control rods and one group of emergency shutdown rods were placed in the core to satisfy the requirement of reactivity and emergency shutdown. The B4C with good absorbing capacity in fast and thermal energy region was used as the neutron absorb material of control rods while tungsten with high density and excellent neutron absorb capacity was mixed with B4C as the neutron absorber material of the emergency shutdown rods. Then neutronics parameters of reactor core were calculated from the beginning of full power operation to the whole life cycle.ResultsThe calculation results show that the 6EFPY life length of this design is achieved, mass of actinide elements decreases and mass of 239Pu was increases apparently. Important reactivity feedback coefficients, such as coolant density coefficient, coolant void value and expansion coefficient are negative, and the value of control rods and safety rods are enough to shutdown reactor in the whole life cycle. Highest clad temperature and fuel center temperature, line power density are within allowed limits.ConclusionsThe main neutronics parameters in the whole life cycle of this preliminary design meet the safety requirements.  
        关键词：Lead cooled;Small reactor;Preliminary design   
        338
        |
        26
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110499 false
        发布时间：2024-10-25
      • “在核反应堆领域，专家结合水辐照分解和材料腐蚀速率计算，评估了水辐解对反应堆材料腐蚀速率的影响。”
        WANG Xiaodong,ZHANG Jingyu,CHEN Yixue,GUO Qingyang,FAN Yuxuan,LIANG Qiuying,XIONG Wenwen
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080002
        摘要：BackgroundAs one of the main coolants of reactor, water generates radiolysis when passing through the radiation zone of the reactor core, and produces oxidizing species such as O2 and H2O2, which will affect the corrosion rate of the material and then affect the source term of active corrosion products (ACPs).PurposeThis study aims to establish a method to calculate the corrosion rate of reactor materials by analyzing the radiation decomposition effect of water.MethodsBased on the existing theories and models, the calculation of water irradiation decomposition was combined with the calculation of material corrosion rate. Concentrations of O2 and H2O2, the main products of water irradiation decomposition, were obtained and the effect of O2 and H2O2 on the corrosion rate of the 316 stainless steel (SS316) material was calculated by combining the theory of mixed potential and Faraday's law.ResultsThe calculation results show that the yields of O2 and H2O2, the main products of water radiolysis in the cooling circuit of the water-cooled reactor, are between 0.1~10 μmol·L-1 under normal operating conditions, and the electrochemical corrosion rate of SS316 is in the range of 0.012~0.026 g·m-2·h-1.ConclusionsWater radiolysis is an important factor affecting the corrosion rate of reactor material SS316.  
        关键词：Water radiolysis;SS316;Corrosion rate;Nuclear reactor   
        326
        |
        23
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110710 false
        发布时间：2024-10-25
      • “在熔盐快堆增殖领域，研究者基于双流体方案，利用熔盐中铀钚重金属盐的高溶解度特性，获得高增殖能力。通过计算分析，氯盐方案具有更大的增殖优势，为熔盐快堆设计提供参考。”
        LI Dongguo,ZHOU Xuemei,LIU Guimin
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080003
        摘要：BackgroundMolten salt reactor has been selected as one of the candidates for the fourth generation reactors due to its superior performance, and molten salt fast reactor has become one of the hot research subjects in the world.PurposeThis study aims to find the most suitable molten salt fuel scheme in the uranium-plutonium cycle to achieve the purpose of high proliferation of fissile nuclides.MethodsBased on the two-fluid cooling cycle scheme, independent cooling cycles for fission molten salt fuel and breeding molten salt, a comprehensive simulation program SCALE (Standardized Computer Analyses for Licensing Evaluation) was employed to calculate the neutron spectrum and reactivity temperature coefficient of three feasible molten salt fuel schemes (LiF+PuF4+UF4, NaF+PuF4+UF4 and NaCl+PuCl3+UCl3). High breeding ratio (BR) in the molten salt fast reactor was realized by utilizing the high solubility characteristics of plutonium and uranium heavy metal salts in fluorinated or chlorinated molten salts at high temperatures. Influence factors of BR, such as the sizes of fission zone, breeding zone and ZrC reflection layer, the isotopic abundances of 6Li and 35Cl in the molten salt, as well as the dynamic change of BR with running time, were computationally analyzed.ResultsThe BR of two fluorinated molten salt schemes reaches about 1.06 whilst BR of the chlorinated molten salt scheme reaches 1.46 when the diameter and height of the fission zone are both 260 cm.ConclusionsCombined with the phase diagram of molten salt, the variation curve of BR with the molar concentration of heavy metals and the variation curve of the maximum value of BR with the average operating temperature of molten salt, the operating temperature of molten salt, the molar concentration of heavy metals and the reactor BR can be be quickly determinated in the conceptual design of the molten salt fast reactor.  
        关键词：Molten salt reactor;Fast neutron reactor;Breeder;Neutron physics;Uranium-plutonium cycle   
        312
        |
        25
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110469 false
        发布时间：2024-10-25
      • “在核反应堆领域，研究人员对新型反应性等效物理变换方法进行了初步探索，使其适用于硼等吸收截面随燃耗变化剧烈的可燃毒物，为RPT方法的扩展和应用提供思路和借鉴。”
        LOU Lei,YAO Dong,CHAI Xiaoming,YU Yingrui,WANG Lianjie,PENG Xingjie WANG Chenlin,XIE Yunli,LIU Yong,XIAO Peng
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080004
        摘要：BackgroundThe traditional volumetric homogenization method (VHM) for the calculation of double heterogeneous system with dispersed particle fuel or burnable poison will bring a certain calculation deviation.PurposeThis study aims to explore the traditional reactivity-equivalent physical transformation (RPT) method applied to the calculation of infinite neutron multiplication factor (kinf) for the accident tolerance fuel.MethodsFirst of all, grid cell containing B4C poison particles in grain model (GM) and VHM model was built to calculate and compare the variation of kinf. Then, the RPT method was employed to treat dispersed particle-type fuel and dispersed particle-type burnable poisons. Finally, a new RPT method with assumption that all the fuel particles were sealed in an annular region in the matrix with the same center of the pellet was implemented to calculate kinf for various accident tolerance fuel.ResultsComparison results show that the new RPT method not only can treat dispersed fuel particles and burnable particles with similar effect of traditional RPT, but also suits for strong absorber dispersed particle-type burnable poisons that the traditional RPT method is ineffective.ConclusionsThe new RPT method can solve the double non-uniformity problem of dispersed fuel and dispersed burnable poison, providing ideas and reference for the expansion of RPT method to strong absorber dispersed particle-type burnable poisons.  
        关键词：Accident tolerance fuel;Double-heterogeneity;Traditional RPT method;New RPT method   
        315
        |
        20
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110468 false
        发布时间：2024-10-25
      • “在核能领域，专家基于LADRC理论设计了熔盐堆功率控制器，具有快速调节速度和精度，对测量噪声不敏感，有良好的抗扰效果。”
        LIU Xiao,LUO Zhipeng,WANG Peilin,ZHOU Shiliang,ZHAO Pengfei,JIANG Zeyu
        Vol. 43, Issue 8, Article number: 080005(2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080005
        摘要：BackgroundPower control system is one of the most essential systems of reactor control, which plays an utmost role in ensuring safe and steady running of the reactor. A well-designed molten salt reactor (MSR) power controller should have better transient response characteristics, hence a simple and efficient control method is needed to ensure its responding speed and better control accuracy.PurposeThis study aims at method of the linear lctive disturbance rejection control (LADRC) applied to MSR power control.MethodsBased on LADRC theory, a power controller was designed for MSR. The second order nonlinear differential equation of relative power and its corresponding linear extended state observer (LESO) for ADRC design were derived. Finally, MATLAB SIMULINK was employed to simulate the performance of this control method.Results & ConclusionsThe simulation results show that the LADRC-based controller model is suitable for power control of MSR, which has the characteristics of fast respond speed, good control performance as well as insensitivity to measurement noise. Hence, the LADRC-based reactor power controller possesses great disturbance rejection ability.  
        关键词：LADRC;Power control;MSR;Estimate of total disturbance   
        324
        |
        23
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110544 false
        发布时间：2024-10-25
      • “在深空探索领域，空间核反应堆电源研究取得新进展。专家基于熔盐冷却方案，利用蒙特卡罗程序和数据库，研究了燃料棒材料、棒间距等因素对堆芯性能的影响，为空间核反应堆设计提供参考。”
        LI Ting,ZHUANG Kun,SHANG Wen,TANG Xiaobin
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080006
        摘要：BackgroundSpace nuclear reactor (SNR) has attracted more and more attention worldwide due to its significant advantages in deep space exploration. Different from the traditional liquid metal, gas and heat pipe cooling methods, molten salt coolant can dissolve fission materials with good heat transfer properties, hence can be used as a coolant in SNR scheme.PurposeThis study aims at the preliminary neutronics design for molten salt cooled SNR.MethodsBased on the design scheme of SNR, Monte Carlo code SERPENT and database ENDF/B-Ⅶ.1 were employed for preliminary neutron design of SNR with molten salt cooling. The effects of different fuel, cladding materials, rod pitch on the kinf of fuel rods and effects of different molten salts, reflector materials on the keff of core were investigated. Finally, a preliminary SNR core scheme based on fluoride salt 7LiF-BeF2-UF4 (66.4-32.7-0.9 mol%) to cool UC fuel (235U, mass fraction at 80%) was proposed.ResultsThe results show that keff of fuel rods is closely related to the fuel material, it increases with the 235U enrichment of fuel and decreases with the rod pitch.ConclusionsDifferent molten salts and reflector materials have great influences on keff of reactor core, but the 235U enrichment of UF4 in coolant is not sensitive to keff.  
        关键词：Space nuclear reactor;Molten salt cooling;Neutronics;Reactivity coefficient   
        330
        |
        28
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110613 false
        发布时间：2024-10-25
      • “在核能领域，全陶瓷微封装燃料研究取得进展，13×13栅格形式的FCM燃料组件可满足欠慢化要求，为商业压水堆堆芯安全性和经济性提供解决方案。”
        QIN Xue,LI Mancang,LIAO Hongkuan,YU Yingrui QIN Dong,JIANG Zhumin,WANG Shuai,CAI Yun,GUO Rui
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080007
        摘要：BackgroundDuring the Fukushima accident, the shortcomings of the existing UO2-zirconium alloy fuel form in resisting severe accidents were exposed. Fully ceramic microencapsulated fuel (FCM) disperses tri-structural iso-tropic (TRISO) fuel particles in a SiC matrix and has the ability to contain fission products, hence can effectively improve the ability of nuclear fuel to maintain structural integrity under severe accidents. FCM fuel can reduce the risk of large quantities of radioactive materials leakage in nuclear power plants, it is one of the main research objects of accident tolerant fuel (ATF). Compared with the traditional UO2 ceramic fuel pellets, the U loading of FCM fuel has better moderation ability and less U loading. When the FCM fuel is used in a commercial pressurized water reactor (PWR), it may cause the positive moderator temperature coefficient (MTC) and loss of inherently safety of the core.PurposeThis study aims to analyse the neutronics characteristics of commercial PWR using FCM fuel from the perspective of inherent safety and economy.MethodsThe UO2-Zr alloy fuel assemblies in the form of standard AFA3G 17×17 grid were taken as reference objects. The NESTOR software independently developed by China national nuclear corporation (CNNC) was employed to analyse the neutron characteristics of FCM fuel (UN core) assembly in forms of 17×17 grid and 13×13 grid. The overall physical performances of the reactor core composed of FCM fuel (UN core) in the form of a 13×13 grid were evaluated.ResultsComputational results show that FCM fuel (UN core) assembly in the form of 13×13 grid containing gadolinium poisons meets the requirements of under moderation, and the FCM fuel (UN core) assembly in the form of 13×13 grid can be adapted by large commercial PWR with negative MTC at the initial stage while the fuel consumption depth and cycle length of the first cycle core are basically equivalent to those of the reference core.ConclusionsFCM fuel assemblies used in commercial PWR can initially meet the inherent security and economic requirements. Further research work will be carried out to optimize the analysis of core power flattening.  
        关键词：FCM fuel;PWR;Neutronics analysis   
        322
        |
        25
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3111053 false
        发布时间：2024-10-25

        SYNCHROTRON RADIATION TECHNOLOGY AND APPLICATIONS

      • “在高压X射线衍射实验领域，专家建立了脉冲激光加热方法，有效阻止金刚石样品腔内化学反应，为原位脉冲激光加热研究提供条件。”
        CUI Weiran,LI Xiaodong,GONG Yu,LI Yanchun,YANG Dongliang,ZHANG Junran,XU Yixuan
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080101
        摘要：BackgroundCompared with the traditional continuous-wave laser heating method, the pulse laser heating (PLH) technology can minimize the heating time to prevent the potential chemical reactions in the sample chamber of diamond anvil cell.PurposeThis study aims to construct an in-situ pulsed laser heating method which can be applied in high pressure X-ray diffraction experiments.MethodsBased on the continuous-wave laser heating system of the high-pressure beamline of Beijing synchrotron radiation facility (BSRF), a signal generator was used to synchronize the pulsed laser, charge coupled device (CCD) spectrometer and X-ray detector, made it capable to heat the sample with pulsed laser, and collect the thermal radiation spectrum and high-pressure diffraction data during heating. The temperature stability, repeatability and temperature gradient of Pt samples heated by pulsed laser under high pressure were measured, and the in-situ X-ray diffraction experiments were completed by using the cumulative time method.ResultsExperimental results show that the axial temperature gradient is larger when the temperature is low, but decreases with the increase of temperature. The PLH high-pressure XRD experimental data of Pt with good quality are collected by using the in-situ X-ray diffraction patterns.ConclusionsThe in-situ PLH method for high-pressure X-ray diffraction experiments enables the pulsed laser to have heating ability at the high-pressure beamline of BSRF, and lays a foundation for the future research on the application of related methods at the new High Energy Photon Source (HEPS) in Beijing.  
        关键词：Synchrotron radiation;High pressure;Pulsed laser heating;X-ray diffraction   
        329
        |
        20
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110666 false
        发布时间：2024-10-25

        ACCELERATOR, RAY TECHNOLOGY AND APPLICATIONS

      • “中国散裂中子源二期工程设计了低β超导椭球腔，优化后腔型在峰值场0~80 MV∙m-1区间，二次电子发射系数小于1，表明整个腔体不会发生Multipacting效应。”
        QU Peihua,LIU Huachang,LI Bo,WANG Yun,LI Ahong,CHEN Qiang,WU Xiaolei,FAN Mengxu,PENG Jun,LUO Xibao
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080201
        摘要：BackgroundA low β superconducting elliptical cavity was designed for the Chinese spallation neutron source-II (CSNS-II) project.PurposeThis study aims to optimize the electromagnetic design of this cavity to its parameters and evaluate its secondary electron multiplication.MethodsThe 2D program SUPERFISH was used to optimize the cell size and high-frequency parameters of the cavity. The operating frequency of the cavity was 648 MHz, the geometry β (βg) was 0.47, and the number of cells was 5. Then, 2D software "Multipac" software and 3D software "computer simulation technology particle studio" (CST PS) were employed to analyze the secondary electron multiplication of the optimized cavity.ResultsOptimization design results show that the peak electric field ratio Epk/Eacc, the peak magnetic field ratio Bpk/Eacc and the axial electric field flatness are 3.35, 6.1 mT∙(MV/m)-1 and 98.42%, respectively. The results 2D software show that in the peak field range from 0 to 80 MV∙m-1, the secondary electron emission coefficient is less than 1, indicating that Multipacting (MP) effect does not occur. However, the results of 3D software illustrate that the MP does exist at the equator of the ellipse. A small convexity induced at the equator, as well as proper post-processing and high-power conditioning, are shown significant suppression of MP.ConclusionsCompared with the same type of low β elliptical cavity in the world, the main high-frequency performance parameters of designed low β superconducting elliptical cavity for CSNS-II are basically equivalent.  
        关键词：Low β superconducting elliptical cavity;SUPERFISH   
        381
        |
        24
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110777 false
        发布时间：2024-10-25

        NUCLEAR CHEMISTRY, RADIOCHEMISTRY, RADIOPHARMACEUTICALS AND NUCLEAR MEDICINE

      • “在神经炎症PET显像研究领域，专家开发了18F-PBR06自动化合成流程，制备出满足科研和临床应用要求的制剂，为神经炎症PET显像研究奠定了基础。”
        QIAO Hongwen,LI Ze,CHEN Shu'an,LIANG Zhigang,LU Jie
        Vol. 43, Issue 8, Article number: 080301(2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080301
        摘要：BackgroundThe 18 kDa translocator protein (TSPO) is an important neuroinflammatory imaging target for neurological diseases. 18F-PBR06 is a second-generation TSPO targeting agent with suitable biological properties, which has been used for human imaging.PurposeThe study aims to promote the application of the imaging tracer 18F-PBR06 in research and clinical studies.MethodsThe disposable cassette system and process sequence for the Neptis Perform synthesizer was developed to produce 18F-PBR06. The quality control inspection method and specification for the product were established with reference to the Chinese Pharmacopoeia (2015 edition). The safety of the product was confirmed by the abnormal toxicity test following the requirements of the Chinese Pharmacopoeia (2015 edition). The biodistribution of the product was evaluated with normal mice. Based on the above research, the preliminary study of 18F-PBR06 PET imaging on healthy controls and patients with multiple sclerosis was performed.Results18F-PBR06 is successfully prepared with a radiochemical yield of (32±5)% (decay corrected, n=20), radiochemical purity >99%, specific activity >111 GBq∙μmol-1, and total time is (54±2) min (n=20). The product quality control tests and abnormal toxicity inspection are in compliance with the requirements of the Chinese Pharmacopoeia. The biodistribution study shows that high uptake is found in the organs of high densities of TSPO, including lung, kidney, spleen and heart. Preliminary PET/CT imaging research results show that the radioactive uptake in thalamus and pons of multiple sclerosis patient brain is significantly higher than that of health controls, and the white matter uptake is moderately increased.ConclusionsThe above results prove that 18F-PBR06 can be prepared through the process developed in this study. The product meets the requirements of research and clinical applications. This study makes favorable preparations for further clinical neuroinflammation PET imaging studies.  
        关键词：Neuroinflammation;PET imaging;18F-PBR06;Automated preparation;Multiple sclerosis   
        374
        |
        23
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110824 false
        发布时间：2024-10-25

        NUCLEAR ELECTRONICS AND INSTRUMENTATION

      • “在核监测领域，基于6Li+CdTe的新型中子探测器方案被提出，模拟研究获得最佳工作参数，为特殊核材料监测提供指导。”
        MA Long,TIAN Lichao,MA Yanyun,LYU Zhongliang,HAN Peng,PENG Meng,YANG Xiaohu,ZHANG Guobo,LI Xiaoxiao,SHAN Fei
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080401
        摘要：BackgroundFacing the internationally serious shortage of 3He gas, a novel neutron detector based on 6Li+CdTe was proposed in 2018, which has high neutron detection efficiency and low γ sensitivity, showing a good application prospect.PurposeThis study aims to conduct an optimal design of the neutron detector based on 6Li+CdTe and explore its application to the special nuclear material monitoring system.MethodsFirst, the structure and operating principle of a typical 6Li+CdTe unit was analyzed. Then the Monte Carlo simulation of MCNP6 was employed to optimize the key parameters of this detector. Finally, integrated analysis was performed using this model for the special nuclear material monitoring system.ResultsThe optimal thickness of the CdTe absorption layer is 10 μm. When the number of 6Li+CdTe detection units reaches 6 layers with the optimal 6Li layer of 60 μm, the detection efficiency is more than 50%. A detector system with an area of 4 m×32 cm, surrounded by polyethylene of 3 cm in the front and 10 cm in the side and back, can meet the requirements of the special nuclear material monitoring system.ConclusionsThe novel neutron detector with optimal design can be used as the alternative of 3He based neutron detector in the special nuclear material monitoring system.  
        关键词：Neutron detection;Semiconductor detector;6Li;MCNP simulation   
        389
        |
        29
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3111010 false
        发布时间：2024-10-25
      • “在探测器信号模拟领域，研究人员设计了一款硅漂移探测器信号模拟器，采用FPGA作为核心器件，利用其可编程逻辑资源产生振荡环，生成均匀分布的真随机数。通过伯努利试验转化为指数分布脉冲序列，经NIST随机性测试，输出脉冲时间间隔、计数率、电压和最小时间间隔均满足要求，可长时间稳定工作。”
        YU Nian,XU Yupeng,HUO Jia,CHEN Yong,CUI Weiwei,LI Wei,ZHANG Ziliang,HAN Dawei,WANG Yusa,CHEN Can,ZHU Yuxuan,ZHAO Xiaofan
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080402
        摘要：BackgroundThe enhanced X-ray Timing and Polarimetry mission (eXTP) is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The spectroscopic focusing array (SFA) is one of eXTP's four payloads, and its main function is to achieve spectrum and timing measurements with high dynamic range and high signal-to-noise ratio (SNR). The SFA uses multi-pixel silicon drift detector (SDD) as the focal plane detector.PurposeThis study aims to design an SDD signal emulator for the performance test of SFA readout electronics.MethodsThe field programmable gate array (FPGA) was used as the core device of this emulator, making use of its abundant programmable logic resources to generate multiple groups of oscillatory loops. First of all, the configurable logic blocks inside the FPGA were designed as multiple oscillating rings, and its outputs were XOR-ed as true random numbers generator (TRNG). By Bernoulli trials, the uniform random numbers were converted into exponential pulse sequence. Then, the NIST (National Institute of Standards and Technology) suite was employed to test the quality of the TRNG output. Finally, the time interval distribution and counting rate characteristic of output pulses for the emulator were tested.ResultsThe sequence of true random numbers of 1 000 Mbits have passed the NIST randomness test. The time interval of the output pulses for the emulator follows the exponential distribution. The dynamic range of counting rate is 1.6 ks-1 to 813.8 ks-1. The voltage range of the output pulse is 2.5 mV to 50 mV, and the minimum time interval is 9.6 ns. The signal emulator can work steadily for a long time.ConclusionsThe SDD signal emulator proposed in this paper can meet the requirements of performance tests for the SFA readout electronics.  
        关键词：Silicon drift detector;Signal emulator;True random number generator;Exponential distribution;Field programmable gate array   
        346
        |
        22
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110961 false
        发布时间：2024-10-25

        NUCLEAR PHYSICS, INTERDISCIPLINARY RESEARCH

      • “在中子俘获截面测量领域，中国散裂中子源利用脉冲高度权重技术，成功验证了金靶中子俘获截面的可靠性。”
        LI Xinxiang,LIU Longxiang,JIANG Wei,REN Jie,WANG Hongwei,FAN Gongtao,CAO Xiguang,HU Xinrong,ZHANG Yue,WANG Junwen,HAO Zirui,JIANG Bing,WANG Xiaohe,HU Jifeng,WANG Jincheng,WANG Dexin,ZHANG Suyalatu,LIU Yingdu,MA Xu,MA Chunwang,WANG Yuting,AN Zhendong,HE Jianjun,SU Jun,ZHANG Liyong
        Vol. 43, Issue 8, (2020) DOI: 10.11889/j.0253-3219.2020.hjs.43.080501
        摘要：BackgroundPulse height weighting technology is a data processing method for measuring neutron capture cross section with C6D6 detector.PurposeThis study aims to measure the neutron capture cross section of 197Au on the back-n target station of China spallation neutron source (CSNS) by using Pulse height weighting technology, and verify the feasibility and data processing of this method.MethodsFirst of all, detection efficiency of the detector, the pulse height weighting function of C6D6 and other basic terms under different target conditions were simulated by Geant4 Monte Carlo code, so that the weighted detector efficiency was proportional to the gamma energy. Then experimental measurement of neutron capture cross section of 197Au was carried out by the Au target calibration data in the experiment.Results & ConclusionsThe experimental results show that the measured neutron capture cross section data are consistent with the ENDF/B-VIII.0 evaluation data. Inconsistent size of the carbon target and the sample target, and the increase of the proton beam power will cause a large error in the background subtraction.  
        关键词：Neutron capture cross section;White light neutron source;Pulse height weighting techniques   
        492
        |
        33
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 3110911 false
        发布时间：2024-10-25
      0