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The behavior of cesium adsorption on zirconyl pyrophosphate

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nuclear Science and Techniques 2016年第3期27卷 74-79页

作者： feng-li song xiao-wei yang xiao-long li wei he dan lü ji que chun-long zhang shan-gui zhao shi-jun wang yun-tao liu nuclear and radiation safety Center Ministry of Environmental ProtectionBeijing 100082China

Zirconyl pyrophosphate(ZrP_2O_7) was prepared and Cs adsorption behavior was *** show that the distribution coefficient of Cs adsorption on ZrP_2O_7 was about 2800 mL/*** exchange capacity of ZrP_2O_7 was0.35 mmol/*** dynamic tests,Cs can be separated from other fission products very well by ZrP_2O_*** ZrP_2O_7was stable both at high temperatures and in high concentration of nitric *** Cs adsorption by ZrP_2O_7 is a monolayer and chemical adsorption.

关键词：吸附行为磷酸锆铯动态测试分布系数交换能力裂变产物化学吸附

Accident source term and radiological consequences of a small modular reactor

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nuclear Science and Techniques 2023年第3期34卷 82-92页

作者： Hai-Ying Chen Fu-Dong Liu Shao-Wei Wang Yi-Chuan Wang Chao Xu Qiao-Feng Liu nuclear and radiation safety Center Ministry of Ecology and EnvironmentBeijing 102401China State Environmental protection Key Laboratory of nuclear and radiation safety Regulatory Simulation and Validation Beijing 102401China

Considering the growing global demand for energy and the need for countries to achieve climate goals,there is an increasing global interest in small modular reactors(SMRs)and their *** source term and radiological consequence evaluations of SMRs are key components of nuclear and radiation safety reviews,which affect the site,exclusion area(EAB),and low population zone outer *** on the design characteristics of the SMR and accident analysis results,a theoretical model of a whole-core fuel cladding damage accident was constructed to study the radioactivity released into the environment and its *** accident source term and radiation dose calculation models were established to analyze the released amounts of radionuclides and the total effective dose affecting individuals at the site *** results showed that the amount of radionuclides released into the environment after a whole-core fuel cladding damage accident reached 10^(14) Bq,among which the release amount of ^(133)Xe was the *** total effective dose at the site boundary 30 days after the accident was 8.65 *** highest total effective dose affecting individuals occurred to the *** results of the accident source term and radiological consequence provide technical support for site boundary dose assessments and reviews of SMRs.

关键词： Small modular reactor Accident Source term Radiological consequence Total effective dose

Development of three dimensional discrete ordinates-Monte Carlo coupled system

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nuclear Science and Techniques 2014年第A1期25卷 42-44页

作者：韩静茹刘巧凤陈海英张春明 nuclear and radiation safety Center of Ministry of Environmental protection Beijing 100082 China

The radiation shielding calculations of large nuclear facilities are complicated due to their bulk shields and complex geometries. A program system based on three-dimensional discrete ordinates (SN)-Monte Carlo (MC) coupled method has been developed to solve this kind of shielding problems. SN method is used to treat the deep penetration problem in the bulk shield, and MC simulation is performed with complex geometry. The coupled method is implemented in the interface program to calculate the probability of particle variables from the SN angular flux distribution. A special source routine is written and linked to MC code to processed these probability arrays and sample the particle variables to generate source for the use of MC code. The H. B. Robinson Unit 2 pressure vessel benchmark was used to validate the SN-MC coupled program system. The specific activities for the six dosimeters in the surveillance capsule were calculated. Satisfactory agreements were obtained from the comparisons of SN-MC results with those obtained from measurement and other computer codes. The result demonstrates that the SN-MC coupling scheme with the program system is suitable to treat three dimensional shielding problems with satisfactory accuracy. © 2014, Science Press. All rights reserved.

关键词：耦合系统蒙特卡洛坐标屏蔽计算程序系统散发 3维几何形状

A new method for position-sensitive measurement of beta surface contamination

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nuclear Science and Techniques 2017年第2期28卷 49-56页

作者： Yan-Tao Qu Hui Wang Yang Liu Ling Chen Jie Hou Zhe Liu Ji-Zeng Ma Department of radiation protection China Institute of Atomic Energy Beijing 102413 China nuclear and radiation safety Center Ministry of Environment Protection Beijing 100082 China Occupational radiation protection Unit Radiation Safety and Monitoring Section NSRW IAEA PO Box 1001400 Vienna Austria

In this paper, we propose a new method for position-sensitive measurement of beta surface contamination. With a position-sensitive detector of enlarged sensitive detection area, accurate information of the contamination distribution can be obtained. The positionsensitive detection is based on a large-area plastic scintillator and the wavelength shifting(WLS) fibers and adopts the ‘‘light center of gravity'' method. Optical transmission of the detector is simulated with a preliminary detector model, and feasibility of the detector design and measurement method is evaluated using an experiment *** simulation and experiment results at different beta-ray incident points on the scintillator surface show that there is a polynomial relationship between the average amplitude ratio of the output pulses from the two parallel WLS fibers in the same fiber layer and the relative distance from the incident point to the WLS fiber.

关键词： Beta surface contamination Position-sensitive measurement Wavelength shifting fibers Plastic scintillator

Effects of Lead on the Initial Corrosion Behavior of 316LN Stainless Steel in High-Temperature Alkaline Solution

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 89-97页

作者： Jia-Min Shao Cui-Wei Du Xin Zhang Li-Ying Cui Corrosion and protection Center University of Science and Technology Beijing nuclear and radiation safety Center Ministry of Environmental Protection of P.R.China

The effect of lead on the initial corrosion behavior of 316 LN stainless steel has been investigated by U-bend immersion experiments in 4 wt% NaOH solutions at 300 °C. Follow-up studies after soaking were carried out by scanning electron microscope, energy dispersive X-ray spectrometer, X-ray photoelectron spectrometer, Auger electron spectroscopy and Raman spectroscopy. The results show that lead affects the properties of the oxide film by changing the thickness and composition, which leads to an increase in the sensitivity of stress corrosion cracking of 316 LN stainless steel. Pits and cracks appeared on the surface of 316 LN stainless steel under both lead-free and lead-containing conditions. The corrosion products were oxides of Fe, Cr and Ni, and the main spinel structure on the surface of the film was NiCr_2O_4 under both conditions. However, in the presence of lead, the cracks and pits were more obvious, the thickness of the film increased from 50 to 200 nm, and the amount of protective NiCr_2O_4 decreased. Lead was concluded to be involved in the dehydration reactions in the form of Pb(OH)_2, which affected the normal dehydration process of the hydroxides and inhibited the formation of spinel structures. Because of the above characteristics of lead, the stability of the oxide film and its protection of 316 LN stainless steel were reduced.

关键词： PbSCC Oxide film 316LN High temperature

Characterization of Corrosion Behavior of Irradiated X65 Low Carbon Steel in Aerobic and Unsaturated Gaomiaozi Bentonite

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Acta Metallurgica Sinica(English Letters) 2019年第4期32卷 506-516页

作者： Canshuai Liu Jianqiu Wang Zhiming Zhang En-Hou Han Wei Liu Dong Liang Zhongtian Yang Key Laboratory of nuclear Materials and safety Assessment Institute of Metal ResearchChinese Academy of Sciences University of Chinese Academy of Sciences China Institute for radiation protection

2.98 kGy/h(1007 h) gamma irradiation and 90 ℃(2000 h) thermal aging were exerted to X65 grade low carbon steel buried in Gaomiaozi bentonite containing 17 wt% Beishan groundwater. The average corrosion rate of X65 low carbon steel was measured. The elemental and phase distribution on cross section was characterized by using electron probe micro-analysis, high-resolution X-ray diffraction, and micro-X-ray diffraction. The following conclusions can be made: the average aerobic corrosion rate of the carbon steel is(45.16 ± 1.53) μm/year. Taking the original surface as boundary, the corrosion scale is divided into an internal dense product layer(DPL) mainly composed of Fe_3O_4 with segregated FeCO_3 at the corrosion front and an external DPL mainly composed of Fe_3O_4 with segregated α-Fe_2O_3 and bentonite at some ***, S, and Cl are concentrated at the corrosion front of the internal DPL, while Si and Al are concentrated at the external DPL.

关键词： Low carbon steel Corrosion rate Phase distribution Elemental concentration

A Low-Cost Dual Energy CT System with Sparse Data

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Tsinghua Science and Technology 2014年第2期19卷 184-194页

作者： Yuanyuan Liu Jianping Cheng Li Zhang Yuxiang Xing Zhiqiang Chen Peng Zheng nuclear and radiation safety Center Ministry of Environmental Protection of China Department of Engineering Physics Tsinghua University

Dual Energy CT （DECT） has recently gained significant research interest owing to its ability to discriminate materials, and hence is widely applied in the field of nuclear safety and security inspection. With the current technological developments, DECT can be typically realized by using two sets of detectors, one for detecting lower energy X-rays and another for detecting higher energy X-rays. This makes the imaging system expensive, limiting its practical implementation. In 2009, our group performed a preliminary study on a new low-cost system design, using only a complete data set for lower energy level and a sparse data set for the higher energy level. This could significantly reduce the cost of the system, as it contained much smaller number of detector elements. Reconstruction method is the key point of this system. In the present study, we further validated this system and proposed a robust method, involving three main steps：（1） estimation of the missing data iteratively with TV constraints; （2） use the reconstruction from the complete lower energy CT data set to form an initial estimation of the projection data for higher energy level; （3） use ordered views to accelerate the computation. Numerical simulations with different number of detector elements have also been examined. The results obtained in this study demonstrate that 1 ＋ 14% CT data is sufficient enough to provide a rather good reconstruction of both the effective atomic number and electron density distributions of the scanned object, instead of 2 sets CT data.

关键词： X-ray imaging dual energy CT system sparse samples reconstruction material discriminationAR^TV

Risk Assessment,Management and Application in nuclear Power Plant Operation

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Journal of Donghua University(English Edition) 2014年第6期31卷 895-898页

作者：圣国龙邱艳荣李琼哲 Suzhou nuclear Power research Institute nuclear and radiation safety Center

To introduce the basic concepts of technical specification of nuclear power plant,a risk assessment and management technique based on the probabilistic safety analysis( PSA) method was proposed. The risk-informed method was used,and an example was given to show how to use some specific risk metrics like CDF / LERF /ICDP / ILERP to analyze and manage the risk associated with activities in nuclear power plant operation. The advantage of this technique can be concluded from this paper,and this technique should be used more widely and deeply in nuclear industry.

关键词： technical specification probabilistic safety analysis(PSA) risk assessment risk management

Framework analysis of fluoride salt-cooled high temperature reactor probabilistic safety assessment

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nuclear Science and Techniques 2015年第5期26卷 112-117页

作者：左嘉旭靖剑平毕金生宋维陈堃 The nuclear and radiation safety Center Ministry of Environmental Protection Shanghai Institute of Applied Physics Chinese Academy of Sciences

Probabilistic safety assessment(PSA) is important in nuclear safety review and analysis. Because the design and physics of the fluoride salt-cooled high temperature reactor(FHR) differ greatly from the pressurized water reactor(PWR), the methods and steps of PSA in FHR should be studied. The high-temperature gascooled reactor(HTR-PM) and sodium-cooled fast reactors have built the PSA framework, and the framework to finish the PSA analysis. The FHR is compared with the PWR, HTR-PM and sodium-cooled fast reactors from the physics, design and safety. The PSA framework of FHR is discussed. In the FHR, the fuel and coolant combination provides large thermal margins to fuel damage(hundreds of degrees centigrade). The tristructuralisotropic(TRISO) as the fuel is independent in FHR core and its failure is limited for the core. The core damage in Level 1 PSA is of lower frequency. Levels 1 and 2 PSA are combined in the FHR PSA analysis. The initiating events analysis is the beginning, and the source term analysis and the release types are the target. Finally, Level3 PSA is done.

关键词：高温气冷堆概率安全评价压水反应堆框架分析安全评估氟盐快中子反应堆物理设计