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Uncertainty and sensitivity analysis of in-vessel phenomena under severe accident mitigation strategy based on ISAA-SAUP program

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Nuclear Science and Techniques 2024年第1期35卷 108-123页

作者： hao Yang Ji-Shen Li Zhi-ran Zhang Bin Zhang Jian-Qiang Shan School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

The phenomenology involved in severe accidents in nuclear reactors is highly ***,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce considerable ***,in recent years,the field of severe accidents has shifted its focus toward applying uncertainty analysis methods to quantify uncertainty in safety assessment programs,known as“best estimate plus uncertainty(BEPU).”This approach aids in enhancing our comprehension of these programs and their further development and *** study concentrates on a third-generation pressurized water reactor equipped with advanced active and passive mitigation *** an Integrated Severe Accident Analysis Program(ISAA),numerical modeling and uncertainty analysis were conducted on severe accidents resulting from large break loss of coolant *** uncertainty parameters of the ISAA program were meticulously *** Wilks'formula,the developed uncertainty program code,SAUP,was employed to carry out Latin hypercube sampling,while ISAA was employed to execute batch *** analysis was then conducted on two figures of merit,namely hydrogen generation and the release of fission products within the pressure *** calculations revealed that hydrogen production and the fraction of fission product released exhibited a normal distribution,ranging from 182.784 to 330.664 kg and from 15.6 to 84.3%,*** ratio of hydrogen production to reactor thermal power fell within the range of 0.0578–0.105.A sensitivity analysis was performed for uncertain input parameters,revealing significant correlations between the failure temperature of the cladding oxide layer,maximum melt flow rate,size of the particulate debris,and porosity of the debris with both hydrogen generation and the release of fission products.

关键词： Gen-III PWR Severe accident mitigation Wilks’formula Hydrogen Fission products Uncertainty and sensitivity analysis

Adaptability of n-γdiscrimination and filtering methods based on plastic scintillation

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Nuclear Science and Techniques 2021年第3期32卷 63-71页

作者： Zhuo Zuo hao-ran Liu Yu-Cheng Yan Bing-Qi Liu Song Zhang Chengdu University of Technology College of Engineering Technology Leshan 614000SichuanChina Southwest Institute of Physics Chengdu 610225China Chengdu University Chengdu 610106China Chengdu University of Technology Chengdu 610225China

Neutrons have been extensively used in many fields,such as nuclear physics,biology,geology,medical science,and national defense,owing to their unique penetration *** rays are usually accompanied by the detection of *** capability to discriminate neutrons from gamma rays is important for evaluating plastic scintillator neutron detectors because similar pulse shapes are generated from both forms of radiation in the detection *** pulse signals measured by plastic scintillators contain noise,which decreases the accuracy of n-y *** improve the performance of n-y discrimination,the noise of the pulse signals should be filtered before the n-y discrimination *** this study,the influences of the Fourier transform,wavelet transform,moving-average filter,and Kalman algorithm on the charge comparison method,fractal spectrum method,and back-propagation neural network methods were *** was found that the Fourier transform filtering algorithm exhibits better adaptability to the charge comparison method than others,with an increasing accuracy of 6.87%compared to that without the filtering ***,the Kalman filter offers an improvement of 3.04%over the fractal spectrum method,and the adaptability of the moving-average filter in backpropagation neural network discrimination is better than that in other methods,with an increase in 8.48%.The Kalman filtering algorithm has a significant impact on the peak value of the pulse,reaching 4.49%,and it has an insignificant impact on the energy resolution of the spectrum measurement after discrimination.

关键词： Fourier transform Wavelet transform Moving average Kalman filter Charge comparison method Fractal spectrum method Back-propagation neural network

Kinetic analysis of austenite transformation for B1500HS high-strength steel during continuous heating

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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1508-1516页

作者： Mu-yu Li Dan Yao Liu Yang hao-ran Wang Ying-ping Guan Key Laboratory of Advanced Forging&Stamping Technology and Science(Ministry of Education of China) Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

The dilatometric curves of B1500HS high-strength steel at different heating rates were measured by a Gleeble-3800 thermal simulator and analyzed to investigate the effect of heating rate on *** show that the value of starting temperature and ending temperature of austenite transformation increase with the rise of heating rates,whereas the temperature interval of austenite formation *** kinetic equation of austenite transformation was solved using the Johnson–Mehl–Avrami model,and the related parameters of the equation were analyzed by the Kissinger *** those calculations,the activation energy of austenite transformation is 1.01×10^6 J/mol,and the values of kinetic parameters n and ln k0 are 0.63 and 103.03,*** relationship between the volume fraction of austenite and the heating time at different heating rates could be predicted using the kinetic *** predicted and experimental results were compared to verify the accuracy of the kinetic *** microstructure etched by different corrosive solutions was analyzed,and the reliability of kinetic equation was further verified from the microscopic perspective.

关键词： B1500HS high-strength steel dilatometric curve austenite transformation kinetic equation Johnson-Mehl-Avuami model

A Structured Ultramicroporous Metal-Organic Framework for Carbon Dioxide Capture

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Chinese Journal of Chemistry 2023年第7期41卷 763-768页

作者： Shao-Min Wang hao-ran Liu Shuang Ni Qing-Yuan Yang School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'anShaanxi710049 China

Comprehensive Summary Carbon dioxide(CO_(2))capture is one of the most important aspects of reducing global *** terms of CO_(2)capture,metal-organic frameworks(MOFs)have several ***,it isn't easy to shape MOFs while maintaining their ***,we describe the development of a pellet-shaped ultramicroporous MOF,Ni(3-ain)2(3-ain=3-aminoinoisonicotinic acid),that is capable of selectively adsorbing CO_(2).Polyvinyl butyral(PVB)is used as a binder during the production of Ni(3-ain)2 MOF *** adequately shaped material can maintain its crystallinity and exhibit a high CO_(2)adsorption capacity(3.73 mmol·g^(-1))at ambient conditions,which is significantly greater than those obtained for N_(2)(0.63 mmol·g^(-1))and CO(0.90 mmol·g^(-1)).Consequently,this material displays high IAST selectivities for CO_(2)/N_(2)(26.3,15/85,V/V)and CO_(2)/CO(19.2,1/99,V/V).According to the theoretical calculations,Ni(3-ain)2 preferentially adsorbs CO_(2)molecules over N_(2)molecules and CO *** results of experiments on dynamic breakthrough have demonstrated that Ni(3-ain)2 pellets are capable of effectively separating CO_(2)/N_(2)or CO_(2)/CO mixtures under conditions of dynamic ***,the structured MOF materials can be synthesized in one step at kilogram *** work provides an avenue for the shaping of MOFs for potential industrial applications in the future.

关键词： Metal-organic framework Shaping Separation Carbon capturel Crystal engineering Microporous materials

DIURNAL CYCleS OF CONVECTIVE AND STRATIFORM PRECIPITATION OVER NORTH CHINA DURING SUMMER

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Journal of Tropical Meteorology 2019年第3期25卷 324-335页

作者： ZHU hao-ran LI Xiao-fan Department of Atmospheric Sciences School of Earth Sciences Zhejiang University

The diurnal cycles of precipitation over northern China during summer in four strong rainfall years are examined using two-dimensional cloud-resolving modeling data. The diurnal signals are analyzed in terms of precipitation budget, fractional rainfall coverage and rain intensity over convective and stratiform rainfall area. The analysis of precipitation budget shows that the diurnal cycles of convective and stratiform precipitation mainly correspond respectively to those of water vapor convergence and transport of hydrometeor from convective rainfall area to stratiform rainfall area in 1964, 1994 and 1995, whereas they mainly correspond to those of water vapor convergence in 2013. The diurnal cycles of convective and stratiform precipitation are mainly associated with those of rain intensity in 1964, 1994 and 1995. In 2013, the diurnal cycle of stratiform precipitation is mainly related to that of fractional rainfall coverage over stratiform rainfall area. The multiple peaks of convective precipitation mainly correspond to the rain intensity maxima associated with strong water vapor convergence.

关键词： diurnal cycle convective and stratiform precipitation water vapor convergence fractional rainfall convergence rain intensity

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基于自研光谱仪的痕量气体光解速率测量研究

光谱学与光谱分析 2025年第1期45卷 15-23页

作者：李浩然曾议朱磊窦科刘志宏常振江宇司福祺中国科学院合肥物质科学研究院安徽光学精密机械研究所环境科学与技术重点实验室安徽合肥230031 中国科学技术大学科学岛分院安徽合肥230026 合肥大学生物食品与环境学院安徽合肥230601

光解速率及其测量技术最早由德国科学家提出,21世纪初Metcon公司开发了光解速率测量仪,该技术在国内得到关注,部分高校和公司对光解速率测量系统开展了研究和开发。国外产品一般体积较大,价格昂贵。国内产品中光谱仪、接收器等核心器件... 详细信息

光解速率及其测量技术最早由德国科学家提出,21世纪初Metcon公司开发了光解速率测量仪,该技术在国内得到关注,部分高校和公司对光解速率测量系统开展了研究和开发。国外产品一般体积较大,价格昂贵。国内产品中光谱仪、接收器等核心器件仍依赖于国外进口,易受国外技术封锁影响。在我国“十四五”国家重点研发计划中“大气与土壤、地下水污染综合治理”重点专项对化学气候综合站检测技术与装备需求引导下,研制了测量大气物质光解速率的光谱仪系统,并满足其核心部件国产化的要求。系统采用自主设计的小型光谱仪作为核心部件,配合各向均匀响应的光学接收器,经实验室光学定标后测得各种物质的光解速率。该系统工作波段为285~430 nm,时间分辨率可达0.1 s,可测物质包括NO_(2)、HONO、HCHO、H_(2)O_(2)等,与国外进口测量仪器对比,各气体物质光解速率的测量误差小于5%,相关性均超过0.93。采用该系统在合肥市董铺岛对大气中气体光解速率开展了长时间的连续监测。对NO_(2)光解速率变化趋势以及NO_(2)光解速率与浓度间的相关性进行分析,发现光解反应与驱动光化反应的能量密切相关,晴天的光解速率数值明显高于阴天与雨天。发现NO_(2)光解速率与浓度的积分曲线间存在一种经验公式,相关性大于0.9,可通过测量NO_(2)光解速率对NO_(2)浓度的累积量进行估计。该系统实现了核心部件的国产化,整体结构简单、便携,方便外场试验安装的同时,降低成本,提高经济性。研究为大气污染综合监测治理提供数据支撑,对各地区的环境监测及污染预防具有参考意义。

关键词：光解速率光谱仪辐亮度光学接收器

Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

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Science China Life Sciences 2025年第1期68卷 300-302页

作者： Ze-Min Lin Mai Xiang Wen-Hui Wei Shu-Hui Fan Li Chen Jie Wang Xiao-Qian Yang Chun-hao Yang Shi-Jun He Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug Research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

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空气悬架系统的理想孪生动挠度跟踪控制策略

西安交通大学学报 2025年第1期59卷 159-171页

作者：赵雷雷张浩于曰伟甄冉丁钒单溪玉丁家和山东理工大学交通与车辆工程学院山东淄博255000 山东安博机械科技股份有限公司研发部山东淄博255000 山东美晨工业集团有限公司研发中心山东潍坊262200

为解决车辆主动悬架系统减振效果与控制能耗间的矛盾,基于“数字孪生、以虚控实、节能减振”理念,提出了主动空气悬架系统的理想孪生动挠度跟踪控制策略。首先,以车辆座椅主动空气悬架系统为例,利用准零刚度系统构建了真实空气悬架系统... 详细信息

为解决车辆主动悬架系统减振效果与控制能耗间的矛盾,基于“数字孪生、以虚控实、节能减振”理念,提出了主动空气悬架系统的理想孪生动挠度跟踪控制策略。首先,以车辆座椅主动空气悬架系统为例,利用准零刚度系统构建了真实空气悬架系统的理想数字孪生体,同时建立了该孪生体的参数匹配设计方法;然后,以空气弹簧气体压力控制为节点,设计了外环位置模糊非奇异快速终端滑模控制器,以及考虑空气弹簧充放气过程中电磁阀非线性流量特性的内环气压控制器,进而实现真实悬架系统对实际激励下孪生体动挠度的跟踪;最后,通过台架模拟实验与整车平顺性仿真实验,对所提控制策略的有效性与先进性进行了验证。结果表明:与以降低加速度为控制目标的传统控制策略相比,所提策略在随机路况下的座椅垂向振动加速度均方根更小且控制能耗均方根最小降幅达65.0%,冲击路况下座椅垂向振动剂量也更小且主动控制力最大降幅高达45.5%。所提策略性能明显优于传统策略,能在有效提高悬架系统减振性能的同时大幅降低主动控制能耗,有效解决了上述矛盾,可推广应用于各类主动悬架系统,为节能减振提供新的研究思路。

关键词：车辆空气悬架节能减振理想孪生动挠度

Influence of Fermion Velocity Renormalization on Dynamical Mass Generation in QED_(3)

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Chinese Physics letters 2012年第5期29卷 209-212页

作者： CHANG hao-ran WANG Jing-Rong WANG Jing Department of Modern Physics University of Science and Technology of ChinaHefei 230026

We study dynamical fermion mass generation in (2+1)-dimensional quantum electrodynamics with a gauge field coupling to massless Dirac fermions and non-relativistic scalar *** calculate the fermion velocity renormalization and then examine its influence on dynamical mass generation by using the Dyson-Schwinger *** is found that dynamical mass generation takes place even after including the scalar bosons as long as the bosonic compressibility parameter (ε) is sufficiently *** addition,the fermion velocity renormalization enhances the dynamically generated mass.

关键词： equation. dynamical scalar