最新刊期
      卷 44 ， 期 12 ， 2021

        SYNCHROTRON RADIATION TECHNOLOGY AND APPLICATIONS

      • “在环境科学领域，专家研究了砷在针铁矿和赤铁矿表面的吸附行为，发现吸附量受pH和铁砷摩尔比影响，为砷污染治理提供新思路。”
        YANG Wang,LIN Jinru,YAO Hui,Yuanming Pan,Emilio Heredia,Roman Chernikov,ZHANG Danni,WANG Shaofeng,JIA Yongfeng
        Vol. 44, Issue 12, Article number: 120101(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120101
        摘要：BackgroundArsenic (As) is one of the most toxic pollutants in the environment. Its adsorption on the surface of iron oxyhydr (oxides) is an important factor affecting its migration and transformation behavior. Goethite and hematite are ubiquitous in soil, groundwater and aquatic sediments. They all have the characteristics of small particle size, large specific surface area, and many active groups, thus can be used as adsorbents for As.PurposeThis study aims to investigate the behaviors of As(V) adsorbed on these two minerals, and determine its complex structures by extended X-ray absorption fine structure spectroscopy (EXAFS).MethodsFirst of all, adsorbents made from goethite and hematite were prepared for experimental measurement of As adsorption at different pH values and Fe/As molar ratios. Then the content of As in the solid phase after adsorption was measured by X-ray fluorescence spectrometer while the surface morphology of the adsorbent was characterized by scanning electron microscope (SEM). Finally, extended X-ray absorption fine structure spectroscopy (EXAFS), obtained at BioXAS beamline of Canadian synchrotron radiation source, was used to detect the coordination numbers of As and Fe adsorbed on the two adsorbents.ResultsThe results show that the adsorption capacity of these two adsorbents for As(V) under acidic pH is greater than that of the adsorbent under alkaline conditions. The adsorption capacity of the two adsorbents decreases with the increase of the Fe/As molar ratio. As(V) adsorption capacity of goethite is larger than that of hematite under the same adsorption pH and Fe/As molar ratio. The EXAFS data shows that the coordination numbers of As-Fe in both goethite and hematite are close to 1, and the distance of As-Fe in different samples is in the range of 3.29~3.31 Å.ConclusionsArsenic mainly forms monodentate-mononuclear complexes after adsorption on the surface of goethite and hematite, which is independent of the experimental pH values and the Fe/As molar ratios.  
        关键词：As(V);Goethite;Hematite;EXAFS;Adsorption   
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        发布时间：2024-10-25
      • “上海光源晶体学线站采用NSGA-II算法，实现线站调光自动化技术升级，提高光束线自动优化效率和水平。”
        ZHANG Ding,WU Yingfeng,HE Yinghua,LIU Ke,WANG Qisheng,HE Jianhua
        Vol. 44, Issue 12, Article number: 120102(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120102
        摘要：BackgroundThe beam quality determined by the beamline status greatly affects the experimental results of macromolecular X-ray crystallography (MX). At present, the optimization of the crystallography beamline of Shanghai Synchrotron Radiation Facility (SSRF) is manually operated by the beamline staffs, which is time-consuming and laborious. X-ray diffractive (XRD) beamline of SSRF realized single-objective automatic optimization of flux based on differential evolution, but this scheme still has certain limitations for MX beamline.PurposeThis study aims to design and implement an automatic optimization procedure based on non-dominated sorting genetic algorithm-II (NSGA-II) on the crystallography beamline system.MethodsFirstly, based on NSGA-II, a multi-objective automatic optimization model of the beamline was established. Then, an automatic optimization procedure was designed and implemented by using Python for the beamline system. Finally, this optimization procedure was tested on BL10U2 of SSRF to optimize the beam flux and position by adjusting the beamline optical components.ResultsThe test results show that the automatic optimization can find the correct optimization objectives Pareto set with two optimized measures of beam flux and beam position within 30 min, and the optimization efficiency is greatly improved when compared with that of manual or previous optimization.ConclusionsNSGA-II based automatic optimization procedure simplifies the optical optimization of beamline and improves the operation efficiency of the crystallography beamlines at SSRF.  
        关键词：Macromolecular X-ray crystallography;NSGA-II;Multi-objective optimization;Pareto set   
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        发布时间：2024-10-25

        ACCELERATOR, RAY TECHNOLOGY AND APPLICATIONS

      • “在放射治疗领域，通过“CPU+多GPU”异构模型加速方案，大幅提高了卷积/积分算法的计算速度，满足临床调强计划设计要求。”
        LAI Jialu,SONG Ying,ZHOU Li,BAI Xue,HOU Qing
        Vol. 44, Issue 12, Article number: 120201(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120201
        摘要：BackgroundThe accuracy of Convolution/Superposition (CS) algorithm is considered to be next to Monte Carlo algorithm (MC) for radiotherapy dose calculation algorithm. Although the calculating speed of this algorithm is much faster than that of MC, its calculating speed can not fully meet the clinical requirements. With the aid of a single graphics processing unit GPU (Tesla C1060), the CS algorithm can be accelerated to 60 times faster than the traditional CPU serial calculation. The calculating time for single field is about 1 min which can be used in some simple three dimensional conformal radiotherapy planning (3DCRT), but this calculating speed does not satisfy the speed need for intensity modulated radiation therapy (IMRT) planning.PurposeThis study aims to explore a faster calculating speed solution of CS algorithm applied to IMRT with multi GPU.MethodsThe acceleration scheme of CPU + multi GPU heterogeneous model was analyzed by using different number of GPUs. High-end GPU, i.e., Tesla C2015, was used for experimental test of CS algorithm executing under the compute unified device architecture (CUDA) platform. Speeds of different number GPUs combined with CPU were compared to find the suitable solution.ResultsThe experimental results show that the speedup of CS algorithm is not completely linear with the number of GPUs. With reasonable number of GPUs and optimized program codes, the computing time of CS algorithm for single field radiotherapy dose calculation can be reduced to 9 seconds by using 7 high-end GPUs (Tesla C2015), 207 times faster than that of a single CPU.ConclusionsWith the implementation of multi GPU heterogeneous model and code optimization, the CS algorithm can be applied to clinical IMRT treatment planning.  
        关键词：Convolution/superposition algorithm;multi GPU;Dose calculation   
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        发布时间：2024-10-25
      • “在硼中子俘获治疗实验装置中，专家设计了一种水冷调谐控制系统，实现了射频四极场加速腔的高精度恒温控制，为治疗装置的稳定运行提供了保障。”
        LIANG Shaoxing,HUANG Jinshu,YE Fan,JIANG Jinxin,OUYANG Huafu
        Vol. 44, Issue 12, Article number: 120202(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120202
        摘要：BackgroundThe radio frequency quadrupole field (RFQ) acceleration cavity in the boron neutron capture therapy (BNCT) experimental device has a characteristic of frequency-selectivity. Water cooling tuning is the process of adjusting the natural resonant frequency of RFQ acceleration cavity to make it consistent with the working frequency of high-frequency power. The natural resonance frequency of the RFQ acceleration cavity is sensitive to the temperature of deionized water in the circulating cooling water system of constant flow process.PurposeThis study aims to design and implement water-cooled tuning system to keep thermostat control within ±0.1 °C of the target value.MethodsBased on the constant flow process circulating cooling water system, a water-cooled tuning control system was developed by using key equipments such as digital high-precision temperature sensors and high-precision temperature control actuators. A constant-temperature and constant flow cooling water circuit for the RFQ acceleration cavity wall and wing was degined to realize the stability and adjustability of the natural resonance frequency of the RFQ acceleration cavity, and finally achieved the RFQ resonance.Results & ConclusionsThe BNCT water-cooled tuning control system of this study is a complete system with functionalities of automatic control, process visualization, data acquisition, historical data storage and remote monitoring. It has been put into formal operation after implementation and commissioning.  
        关键词：Boron neutron capture therapy (BNCT) experimental device;Radio frequency quadrupole field (RFQ) acceleration cavity;Water-cooled tuning control system   
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        发布时间：2024-10-25

        NUCLEAR CHEMISTRY, RADIOCHEMISTRY, RADIOPHARMACEUTICALS AND NUCLEAR MEDICINE

      • “2020年，中国批准氯化镭注射液用于治疗去势抵抗性前列腺癌伴骨转移患者，为全球首个α粒子靶向放射治疗药物。目前，国外已广泛应用核医学技术评估其疗效，国内尚处临床应用初期。”
        LOU Jingjing,LI Tongtong,LIU Xingdang,ZHANG Hong
        Vol. 44, Issue 12, Article number: 120301(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120301
        摘要：Radium-223 dichloride (223Ra) (Sofigo), a calcium-mimetic agent that specifically targets bone lesions, was approved in 2020 by China Food and Drug Administration (CFDA) to treat castration‑resistant prostate cancer and bone metastases (CRPC) with symptomatic bone metastases and no known visceral metastatic diseases. It is the fisrt α particles targeted radiopharmaceutical therapeutic drugs in the world to be applied to CRPC with bone metastase (mCRPC) patients. In recent years, the application of nuclear medicine technology to evaluate the efficacy of 223Ra in the treatment of mCRPC patients abroad has been very common, but only few hospitals in China have entered the stage of clinical application. In order to provide clear recommendations for clinical applications of radionuclide imaging in evaluating the efficacy of 223Ra in the treatment of mCRPC, a survey of recent progress is carried out in this study, and public available clinical data of single photon emission computed tomography/computed tomography (SPECT/CT), and positron emission tomography/computed tomography (PET/CT) using radiolabeled chemical agents worldwide in the evaluation of 223Ra treatment for patients with CRPC and bone metastase,are presented and commented.  
        关键词：223Ra;mCRPC;SPECT/CT;PET/CT   
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        发布时间：2024-10-25

        NUCLEAR ELECTRONICS AND INSTRUMENTATION

      • “在核物理和聚变能源研究领域，专家提出了一种新的大动态范围时间响应特性快速分析方法，为闪烁体类脉冲辐射探测系统设计与优化提供解决方案。”
        HUANG Zhanchang,YANG Jianlun,YI Qiang,LI Mingjia,MENG Shijian,LIANG Chuan,WANG Wenchuan
        Vol. 44, Issue 12, Article number: 120401(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120401
        摘要：BackgroundInternational basic nuclear physics research and fusion energy research need pulse radiation detection system with higher and higher accuracy. A pulse scintillator radiation detection system with large dynamic range is a key method to obtain detailed information such as the time and amplitude of small signals in a strong interference environment, so as to analyze and study the characteristics of these pulse radiation fields.PurposeIn order to meet the needs of covering design and optimization of the scintillator pulsed radiation detection system, a new express analysis method is proposed, which covers a large-scale dynamic range of time response characteristics.MethodsThis new express analytical unit mainly contains a gated photomultiplier tube (PMT), a gated high voltage (HV) and an oscilloscope. Firstly, a picosecond pulsed laser has been used to test the intrinsic property of this method. Finally, the time response characteristic of low-afterglow liquid scintillator has been studied by this method on a pulse X-ray machine. According to the experimental data, a decay curve of the liquid scintillator has been processing with double exponential fitting.ResultsThe decay curve of this liquid scintillator has been measured with a range of four scales.ConclusionsThis method has a vertical scope covering five scales.  
        关键词：Time response;Dynamic range;Scintillation detector   
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      • “在散裂中子源多物理谱仪领域，中国科学家开发了T0信号触发监测系统，实现了对信号频率和时间延迟的实时监测，保障了谱仪的高效运行。”
        YAN Ze,LI Jiajie,WANG Xiaohu,ZHUANG Jian
        Vol. 44, Issue 12, Article number: 120402(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120402
        摘要：BackgroundThe high accuracy and high stability of the T0 signal, taking from initial proton target time, are the prerequisite and basis for the efficient operation of the multi-physics spectrometer of Chinese spallation neutron source (CSNS).PurposeThis study aims to develop a set of CSNS multi-physical spectrometer T0 trigger monitor system running on the experimental physics and industrial control system (EPICS) platform.MethodsFirst of all, the T0 signal was fed into the T0 fan out device for high precise time stamp marking, and the high-throughput distributed publish-subscribe messaging system Kafka was used to achieve peak-shaving and asynchronous communication of big data traffic. Then, the monitored data was uploaded to the EPICS platform as a process variable (PV), and the Open-Falcon monitoring system and the visualization tool Grafana were used to realize the monitoring and visualization of the data.Results & ConclusionsImplemented T0 signal monitoring system can monitor the frequency of the T0 signal of each node and the time delay of T0 in the fan-out and transmission process in real time. so as to ensure the normal operation of the CSNS multi-physics spectrometer.  
        关键词：T0 signal;EPICS;Kafka;Monitoring;Chinese Spallation Neutron Source   
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        发布时间：2024-10-25
      • “在核反应数据领域，专家研制了10单元PPAC，时间响应快，适合高事例率测量。”
        ZHU Yiwei,HUANG Hanxiong,YANG Herun,WANG Xuehao,REN Jie,DUAN Limin,ZHANG Junwei,SUN Qi,RUAN Xichao
        Vol. 44, Issue 12, Article number: 120403(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120403
        摘要：BackgroundThe prompt fission neutron spectrum (PFNS) is an important nuclear reaction data. Coincident measurement between neutron detectors and parallel plate avalanche counters (PPAC) is widely used to measure the PFNS below the energy of the neutron source, hence most of the non-fission neutrons can be exclude.PurposeThis study aims to develop a PPAC to satisfy the PFNS measurement and performance test.MethodsFirst of all, a ten-cell PPAC was designed with low-pressure flow working gas and individual cell functionality. Then the software named "Garfield" was used to simulate the distributions of electric field of two kind of fission chambers, i.e., wire-electrode chamber and plate-electrode chamber, under the same geometric dimensions and working conditions. Finally, the structure and the performance of the PPAC were introduced in detail, and relevant performance of this PPAC was tested by experiment.ResultsThe full width at half maximum (FWHM) of the time-correlated spectrum between two neighbor cells using a 241Am α source is 620 ps. The FWHM of the time-correlated spectrum between a PPAC cell and a liquid scintillator detector is 880 ps using a 252Cf fission source.ConclusionsThe experiment confirms that the time resolution of the designed PPAC is good enough for high event rate measurements.  
        关键词：PPAC;PFNS;Coincident measurement;Neutron spectrum;Time response   
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        发布时间：2024-10-25

        NUCLEAR PHYSICS, INTERDISCIPLINARY RESEARCH

      • “在核数据评价领域，中国原子能科学研究院专家利用多探测器快中子飞行时间谱仪，首次测量了8.0 MeV中子与镓的弹性散射微分截面，为核数据评价提供了实验数据支撑。”
        WANG Xuehao,HUANG Hanxiong,LAN Xiaofei,RUAN Xichao,ZHANG Qiwei,REN Jie,SUN Qi,LUAN Guangyuan,LIU Chao,DING Yanyan,WANG Jincheng,MA Xu,HU Zhijie,GUO Mingwei,JIANG Liyang
        Vol. 44, Issue 12, Article number: 120501(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120501
        摘要：BackgroundDue to the special physical properties of gallium, gallium is considered to be used as reactor coolant in the future. Therefore, a full set of gallium neutron data is needed. However, the experimental data of gallium in EXFOR (Nuclear reaction experimental data) database is rare. There are also some discrepancies among the evaluation data.PurposeThis study aims to obtain elastic scatting differential cross section for natural gallium at 8.0 MeV incident neutrons, so as to fill the blanks of the neutron data of gallium in the database and clarify the discrepancy among the evaluation data.MethodsFirst of all, the elastic scatting differential cross section data of natural gallium was measured at 21 different laboratory angles from 20° to 140° by using the multi-detector fast neutron time-of-flight (NTOF) spectrometer on HI-13 tandem acceleration at the China Institution of Atomic Energy (CIAE). The cross sections of gallium were normalized by n-p elastic scatting cross section, and the quality of data was improved by many methods applied to the measurement and data analysis. Then, the Monte-Carlo code STREUER was employed to rectify the neutron flux attenuation, multiple scattering and the finite geometry of the experiment. Finally, the measured TOF spectra were compared with that of simulated to determine experimental scatting differential cross section of 8.0 MeV incident neutrons.Results & ConclusionsThe results of cross section of secondary neutron for natural gallium are the world's first experimental data in the 8.0 MeV energy region. Compared with the evaluated data, the measured data is generally in good agreement with CENDL-3.2 data, but inconsistent with ENDF/B-8.0 data and JENDL-4.0 data. The divarication among these three data bases has been clarified by the experimental result, hence of great significance to data evaluation and theoretical model improvement.  
        关键词：Secondary neutron;Differential cross section;Monte-Carlo method;Evaluated data   
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      • “中国科学院近代物理研究所专家利用高电荷态氮离子与Cu表面碰撞，系统测量了K-X射线能谱，为理解“空心原子”退激过程和彗星X射线机理研究提供基础数据。”
        LIU Xuan,SONG Zhangyong,ZHANG Bingzhang,QIAN Cheng,FANG Xing,SHAO Caojie,WANG Wei,LIU Junliang,XU Junkui,FENG Yong,ZHU Zhichao,CHEN Lin,GUO Yanling,SUN Liangting,YANG Zhihu,YU Deyang
        Vol. 44, Issue 12, Article number: 120502(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120502
        摘要：BackgroundThe highly charged nitrogen ions (Nq+, q=3, 5, 6) are one of the main charged ions in the solar wind. Study of K-shell X-ray emissions in collisions of Nq+ (q=3, 5, 6) ions with a Cu surface is of great significance for understanding the de-excitation process of "hollow atoms" and the generation mechanism of comet X-rays.PurposeThis study aims to investigate characteristics of K-shell X-ray emission in impacts of Nq+ (q=3, 5, 6) ions with a Cu surface.MethodsThe Nq+ (q=3, 5, 6) ion beam was generated by the electron cyclotron resonance ion source (ECRIS) in Institute of Modern Physics, Chinese Academy of Sciences. The K-shell X-ray spectra resulted from collisions of the Nq+ ions with the Cu surface were acquired by a silicon drift detector (SDD). Based on the X-ray spectra, K-shell X-ray yields and ionization cross sections were calculated.ResultsThe results show that, for the Nq+ (q=3, 5) ion incidence, K-shell X-ray emissions are attributed to close collisions of the ions with Cu atoms on the subsurface of the target, and that the K-shell X-ray yields and ionization cross sections increase monotonically with the increase of kinetic energy of the incident ions. For the N6+ ion incidence, the K-shell X-ray yields have no obvious dependence on kinetic energy of the incident ions. The K-shell X-rays are primarily emitted from the above-surface of Cu target through the de-exciting of the formed "hollow N atoms", and they account for about 97% of the total X-rays. In addition, the X-ray yield of the N5+ ion incidence is higher than that of N3+ ions.ConclusionsThis study provides basic data for the understanding the de-excitation process of "hollow atoms" and the generation mechanism of comet X-rays.  
        关键词：X-ray;Highly charged ion;X-ray yield;Ionization cross section   
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        NUCLEAR ENERGY SCIENCE AND ENGINEERING

      • “在高温气冷堆领域，专家采用ANSYS CFX程序，对MHTGR-350堆型堆芯间隙旁流现象进行三维数值模拟，分析了间隙尺寸对堆芯热工流体性能的影响，为堆芯设计提供参考。”
        DONG Jianhua,WANG Jun,GUO Juanjuan,ZHANG Shuoting
        Vol. 44, Issue 12, Article number: 120601(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120601
        摘要：BackgroundThe core of prismatic high temperature gas-cooled reactor (HTGR) is composed of fuel blocks based on layers and zones. Due to machining deviation and assembly, the gap size between blocks should be ensured. Part of the core coolant will be bypassed into these formed gaps, which can be abbreviated to gap bypass flow.PurposeThis study aims to analyze the impact of gap bypass flow on the thermal-hydraulic performance of the prismatic HTGR which is an important to the core structure and internal design.MethodsFirst of all, the commercial CFD (computational fluid dynamic) software ANSYS CFX was used to carry out the three-dimensional numerical simulation of the complex flow and heat transfer phenomena in MHTGR-350 (modular high-temperature gas reactor 350 MWt) active core. Then the detailed model of blocks, fuel holes, coolant channels and gaps were established to calculate the flow and temperature distribution in the region. Finally, the key parameters of these models were adopted for the sensitivity analysis.ResultsThe calculation results show that the flow rate into the long and narrow gap is mainly determined by the core structural arrangement and the gap size. When the gap size becomes larger, the bypass ratio will also be larger, the cooling efficiency will become worse, and the local fuel temperature will rise.ConclusionsThe gap size will change with the deformation of the core blocks during the operation life of the reactor, which will cause fluctuations in temperature distribution and outlet temperature. Furthermore, the larger the gap, the greater fluctuation range, which is detrimental to the safety and stability of the core operation.  
        关键词：Prismatic high temperature gas cooled reactor;Gap bypass flow;MHTGR-350;Numerical simulation   
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      • “在核能领域，石墨烯纳米颗粒掺杂铅铋堆冷却剂，显著提升导热系数和比热容，助力反应堆小型化和轻量化设计。”
        YANG Tao,ZHAO Pengcheng,ZHAO Yanan,YU Tao
        Vol. 44, Issue 12, Article number: 120602(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120602
        摘要：BackgroundThe thermal conductivity of graphene nanoparticles doped into the lead bismuth reactor coolant can significantly improve the coefficient of thermal conductivity and specific heat capacity. That will improve the core power of lead and bismuth pile density, reduce the amount of coolant, and ultimately achieve the goal of reducing the reactor volume. It is of great significance for the engineering application of lead bismuth reactor in remote areas and offshore seas.PurposeThis study aims to investigate the thermophysical properties of lead-bismuth-based graphene nanofluids.MethodsFirst of all, different thermal conductivity, viscosity, specific heat capacity and other prediction models were employed to study the thermophysical properties of metal-base Graphene nanofluids. The strengthening mechanism of nanofluids was analyzed, then a hermophysical calculation model suitable for lead-bismuth-based graphene nanofluids was put forward.ResultsThe results show that the coefficient of thermal conductivity, specific heat capacity and viscosity of lead bismuth matrix with graphene nanoparticles are significantly improved, and the thermal conductivity, specific heat and viscosity increase significantly with the increase of the concentration when the suspension is relatively stable. When the concentration reaches 20%, the thermal conductivity of mickey fluid can be increased by 80%. However, the viscosity is increased by about 100% simultanously.ConclusionsThe influence on thermophysical property should be considered while increasing the concentration of graphene nanofluids.  
        关键词：Lead-bismuth reactor;Graphene nanofluids;Thermal conductivity;Viscosity;Specific heat capacity   
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      • “在火星探测能源供给领域，科学家提出了一种新型核反应堆方案，为火星表面热管熔盐堆设计提供参考。”
        HU Guang,CUI Deyang,LU Linyuan,LI Xiaoxiao,CHEN Jingen,CAI Xiangzhou
        Vol. 44, Issue 12, Article number: 120603(2021) DOI: 10.11889/j.0253-3219.2021.hjs.44.120603
        摘要：BackgroundNuclear reactors have become the main energy supply for future manned Mars exploration missions due to their high energy density, high power-mass ratio and small size. Heat pipe molten salt reactor is an innovative concept combining molten salt reactor and high temperature heat pipe technology.PurposeThis study aims to carry out preliminary neutronics design of a martian surface molten salt reactor (MS)2R core with 1 MWth and a lifetime longer than 5 a.MethodsFirst of all, the core model of (MS)2R was estabished according to the requirements. It mainly included active zone (including fuel salt and heat pipe), active zone wall, reflector, reactor vessel, etc. Then, the MCNP (Monte Carlo N particle Transport Code) and MOBAT were used to optimize the core size and reactivity control of (MS)2R.ResultsThe physical design parameters of the core are obtained: the height and diameter of the core are 90.94 cm and 88.94 cm, respectively, the uranium inventory is 146.08 kg, and the core mass is 2.09×103 kg. Reactivity control is achieved by a control drum system, in which the B4C (10B enrichment is 90%) with a thickness of 1.8 cm and a wrap angle of 120° is used as the neutron absorber.ConclusionsThe control drum arrangement can meet the critical safety requirements during the lifecycle of (MS)2R under full power (1 MWth) operation for five years, and the number of heat pipes can meet the heat transfer safety limit. This study provides a basic theoretical reference for the design of planet surface molten salt reactor.  
        关键词：Molten salt reactor;Liquid metal heat pipe;Control drum   
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