bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional Reliability Investigation on Capacity of Reactor Core Natural Circulation Cooling in XAPR Under MLOCA
Authors: Wang Baosheng , Ma Tengyue , Bao Lihong , Ma Zhenhui , Hu Pan , Li Da , Su Chunlei , Chen Lixin , Tang Xiuhuan 
Published: November 2022

Abstract
Due to the epistemic uncertainties involved in the numerical values of its parameters and its modeling, the system may not accomplish its function as required. Functional failure becomes an important factors in the natural circulation system operation failure, which needs to be considered in the system reliability analysis. In order to solve the problem of multi-dimensional uncertainty parameters and small functional failure probability of passive systems, an efficient functional reliability estimation method based on improved response surface and importance sampling subset simulation was presented. This method was applied in natural circulation cooling in XAPR reactor core. Combined with MLOCA, the uncertainties related to the input parameters and the model were considered. And then the probability of functional failure and the sensitivity measures were estimated with the combination of response surface method and importance sampling subset simulation method. The assessment results show that the functional failure probability is 3.796 × 10−3, and it is fully considered the functional failure in the passive system reliability analysis. Meanwhile, this method has high computed efficiency and excellent computed accuracy compared with traditional probability analysis methods, and it is robust to nonlinear functional function of XAPR.
A Combined Analytical, Experimental and Simulation Investigation on LBE Natural Circulation Flow and Heat Transmission
Authors: Zhou Yiquan , Kuang Bo , Wang Xin , Wang Shuting , Hu Wenjun , Ren Lixia 
Published: November 2022

Abstract
As one of the proposed six types of Gen-IV nuclear energy systems, lead-cooled fast reactor (LFR) has some advantages in safety, economy, sustainability, and proliferation prevention. With its low melting point, chemical inertia, high boiling point temperature, pretty good neutronics and γ shielding ability, lead bismuth eutectic (LEB) has been one of the common choices of lead-base coolant for fast reactors. A certain natural circulation capacity might be achieved in LBE flow systems due to its relatively high thermal expansion and thus induced buoyancy. Consequently, for the purpose of enhancing natural safety performance and operation economy, as well as for other specific needs, natural circulation is, in recent years, considered for the main heat transmission system or residual heat removal systems in some LBE fast reactor designs. Study of LBE natural circulation along with its heat transmission performance is thus of quite significance for LBE natural circulation fast reactor design and natural safety performance improvement.
In this paper, steady-state flow and heat transmission characteristics and behaviors of LBE natural circulation, as well as those of other coolant media (sodium and water), are theoretically and comparatively studied. Meanwhile, based on both the steady and transient natural circulation experiments on the LBE natural circulation test facility, namely, LNC-SJTU facility, the applicability of the fast reactor system analysis code FRTAC for LBE natural circulation transient simulation is preliminarily validated. And with the prediction of this FRTAC code, furtherly, effects of operating conditions as well as the corresponding fluid thermophysical properties, structural and geometric parameters of the loop, frictional and local resistances on the LBE natural circulation performances are quantitatively investigated.
Software of Radioactivity Measurement and Control System for Barreled Nuclear Waste With Segmented Gamma Scanning
Authors: Yitang Liu , Rui Shi , Zhou Wang , Zhenchuan Wang , Yunliang Lan , Wei Zhao , Xianguo Tuo 
Published: November 2022

Abstract
Segmented Gamma Scanning (SGS) is a kind of nondestructive testing (NDT) techniques, widely used in online detection for nuclear waste drums to record the types and contents of radionuclides in the nuclear wastes. It is convenient to classify and dispose of nuclear waste according to the test results, and it also avoids radiation damage to inspectors from the destructive analysis. A new software of the radioactive analysis and monitoring system for nuclear waste barrels with SGS was developed in this work, which is mainly composed of two parts including control upper computer software and radionuclide analysis software, in which control software contained motion control and Multi-channel Analyzer (MCA) control. The controlling of the mechanical platform realized the rotation of the waste drums and the synchronous lifting and lowering of the transmission source and the detector, so as to facilitate the layered scanning of the drums. The motion control is an indispensable part of the detection system, whose precision of the movement is directly affected the accuracy of the detection results. In the radioactive measurement, a high purity germanium (HPGe) gamma-ray spectrometer was used to obtain the gamma-ray spectrum, in which the MCA was responsible for the control of spectrometer and gamma-ray spectrum data record. Therefore, the MCA control part must adjust the high voltage of the HPGe and the parameters of measurement. The gamma-ray spectrum contained the radioactive information of the nuclear wastes in the drums. The analysis of the radioactive data is the core of the software, including spectrum data resolving and the radioactive reconstructed of the radionuclides in the drums. Finally, the information such as the type and activity of the radionuclides in the barrels was provided to the user. The software was written with the C# programming language, which realized the accurate control and operation of the mechanical device and the orderly performed of motion detection. To establish communication, the software used Ethernet’s TCP/IP as the control network, in which the manual mode and auto mode were alternatives. In conclusion, the software promotes the coordination and integration of motion control, MCA control and gamma-ray spectrum data analysis in the process of automatic detection of barreled nuclear waste with SGS.
Research and Application of Diversity Design of Nuclear Power Plant Based on High-Frequency Occurring Accidents Mitigation
Authors: Xu Jiaoshen , Liu Zhengjie 
Published: November 2022

Abstract
Diversity design is an effective measure to avoid common cause failure, which is of great significance to improve the reliability and safety of nuclear power plants. Especially for those high-frequency occurring accidents mitigation, diversity design plays a significant role. In order to improve its reliability and safety, this paper takes a PWR nuclear power plant as the research object, establishes a diversity design method to mitigate high-frequency occurring accidents, and applies this method to optimize the design of nuclear power plant. In this paper, the safety system of the power station is studied, and a variety of design methods are applied to optimize the design scheme. The results show that this method not only significantly improves the reliability and safety of nuclear power plant, but also plays a great role in the economic operation of nuclear power plant.
The Application of Risk-Informed Management Index in NPPs Risk Management
Authors: Shijun Chen , Yong Zhang , Wenbo Luo , Shuixiang Ye 
Published: November 2022

Abstract
With domestic NPP units increased, it is urgent to establish a more reasonable regulation way with full emphasis on plant significant items. This paper, based on the deterministic methodology and engineering judge, researches the risk-informed management index by applying SDP into events risk evaluation at all sites, which can help forecast the risk trend next month and pre-determine the current NPP risk status of each month with established risk judge criteria. Furthermore, some information and suggestions about risk significant events and risk prediction values are also mentioned in this paper, as well as some examples, in order to offer some references for management level to accomplish the decision-making.
Summary of Geometric Parameters and Their Effects on Performance of U-10Mo Fuel Plates
Authors: Ozaltun Hakan , Roh Hee Seok , Mohamed Walid 
Published: November 2022

Abstract
A monolithic plate-type fuel system has been under development to convert high-performance test reactors from highly enriched uranium to low-enrichment uranium fuels and is now moving into the qualification phase, a predecessor to the timely conversion of the target reactors. To qualify this fuel system, the plates must meet the safety standards and perform well in a reactor. The plates must maintain mechanical integrity, exhibit geometric stability, and have stable and predictable in-reactor behavior. The requirement to maintain mechanical integrity under normal operating conditions is primarily demonstrated by successful testing. However, each high-performance reactor employs distinct design, resulting in distinct plate geometries, with unique features, attributes, irregularities, and tolerances. Due to the abundance of such distinct geometric varieties, a single “generic” plate geometry capturing all the extremes is not achievable. It is also impractical to test each of these proposed designs in a reactor. This limitation necessitates cautious evaluations since the thermo-mechanical response of a plate with a certain geometry may not be representative for a plate with a significantly different geometry. To address concerns related to in-reactor performance of the plates, large set of sensitivity studies were performed. These parametric studies aimed to better understand irradiation performance, while evaluating the sensitivity of results to various modeling inputs, including geometric, operational, and material parameters. This work studied selected geometric parameters based on provided fuel specifications and performed a series of parametric simulations. The resulting temperature, displacement and stress-strains were comparatively evaluated to determine the effects of various geometric parameters. This draft provides a “high-level summary” of parametric sensitivity studies performed and summarizes the key findings from those studies.
Numerical Simulation of Two-Phase Flow Using Eulerian-Eulerian Model With One-Group Interfacial Area Transport Equation
Authors: Liu Yao , Han Jinyu , Zhao Chenru , Bo Hanliang 
Published: November 2022

Abstract
The gas-liquid two-phase flow phenomenon in the vertical circular tube widely exists in a variety of industrial equipment, such as steam generators in the nuclear power plant and the bubble towers. The study of the gas-liquid two-phase flow characteristics, especially the movement characteristics of the gas phase or bubbles is significant. Interfacial area concentration (IAC) is defined as the interfacial area between two phases per unit mixture volume, which is a key parameter to predict the interfacial interaction and transfer terms between two phases. Different IAC represents different flow regime. The IAC changes in various flow regimes are usually modeled by the Interfacial Area Transport Equation (IATE).
In this paper, Eulerian-Eulerian two-fluid model (EE) and mixture model with one-group interfacial Area Transport Equation (IATE) are used to numerically simulate the upwardly flowing gas-liquid two-phase flow in a vertical circular tube. Simulation results are compared with the experimental results of adiabatic air-water upward flow in a tube with inner diameter of 2 mm and 1 MPa in steady-state condition (Hibiki et al.2001) for evaluating the two-phase flow model with one-group IATE model. Three experimental cases under various gas and fluid velocity conditions of 0.734–1.39 and 0.512–1.282 are selected, in which case 1 and 2 are typical bubbly flows, and case 3 is in a transition between the bubbly and the slug flow regimes. The characteristics of two-phase flow under different gas and liquid flow rate conditions are analyzed, and the applicability of one-group IATEs is evaluated, and finally the sub-models that can be improved are analyzed. Results show that one-group IATE is only suitable for bubbly flow.
Study on the Substitute Nuclides of Actinides in High-Level Radioactive Waste Liquid
Authors: Du Yingzhe , Li Lili , Li Kunfeng , Lin Peng , Zhang Yugang , Diwu Juan 
Published: November 2022

Abstract
Actinides have complex chemical properties, there are a variety of oxidation states and changeable coordination configurations, and their physical properties, electronic structure and molecular orbital theory are much more complex than other elements. On the other hand, actinides in high level liquid waste, especially transuranic elements synthesized by artificial nuclear reaction, are highly radioactive, which is critical for its stable glass solidification. At present, taking elements with similar properties as substitutes to simulate actinides and inferring the properties of actinides by analyzing the compounds formed by substitutes is one of the important works of glass solidification. This paper provides a possible way to use trivalent lanthanides as an alternative for trivalent actinides.
Study of Iodine-Induced Stress Corrosion Cracking of CZ2 Alloy
Authors: Shi Lin , Gao Changyuan , Zhang Guoliang , Sun Guocheng , Wang Xu , Chen Liutao , Tan Jun 
Published: November 2022

Abstract
This paper is dealing with the iodine-induced stress corrosion cracking behavior of CZ2 zirconium alloy which is developed by China General Nuclear Power Group. The alloy in this study was fabricated with four different final annealing temperature in the range of 450 °C to 600 °C. In order to investigate the iodine-induced stress corrosion cracking behavior of CZ2 alloy, the slow strain rate tensile tests of four different CZ2 were conducted with three different iodine partial pressure of 0Pa, 10Pa and 10000Pa. The temperature of the tests was 350 °C and the strain rate was 1.4 × 10−6s−1. Also, the sensitivity index of iodine-induced stress corrosion cracking was calculated. The iodine-induced stress corrosion cracking sensitivity index of recrystallized CZ2 alloy is lower than that of stress-relieved CZ2 alloy, and with the increase of final annealing temperature, the sensitivity index decreases gradually. Finally, the fracture surface of CZ2 alloy was observed by scanning electron microscopy. The fracture feature of all four different CZ2 alloy changes from ductile fracture morphology to brittle fracture morphology with the increase of iodine partial pressure. Under the condition of 10000 Pa iodine partial, the fracture feature of stress-relieved CZ2 shows obvious brittle cleavage fracture, the fracture feature of partially recrystallized CZ2 is partly ductile fracture and partly cleavage fracture morphology. For recrystallized CZ2, there are many dimples in the fracture morphology, and shows obvious ductile fracture.
Study on Properties of Aging and Immersion in Boric Acid Water of PEEK Insulation Material
Authors: An Jing , Jin Shan , Zhang Li-Qin , Wu Hao 
Published: November 2022

Abstract
Because of its excellent heat resistance, nuclear radiation resistance, corrosion resistance and high mechanical properties, PEEK is considered as a promising insulating material in the 21st century, but at present, there is still no research on the mechanical property changes after immersion in boric acid water and aging. This paper has deeply studied the above problems through experiments, the test results show that the PEEK material will not crack or break in the air under high stress levels, however, long-term immersion in boric acid solution may lead to complete separation of the two pieces. Soaking in hot water can increase the IS of the PEEK material, so in order to prevent fracture and improve the toughness of the material, the PEEK material may be soaked in hot water for a certain amount of time, and ensure that the sum of preloading force and acting force when the material is used is lower than the allowable stress value after immersion reduction, then can be used.
Cultivation of Future Leaders: A Case Study From the China-IAEA Nuclear Energy Management School
Authors: Yu Aihui , Jing Yuanyuan 
Published: November 2022

Abstract
The development of nuclear energy, technology and applications programmes s creates a continuous need for a global workforce of highly qualified professionals with appropriate nuclear technical and managerial competence. The International Atomic Energy Agency (IAEA) provides the Nuclear Energy Management (NEM) School programme to help the Member States build and train future leaders in managing the national peaceful applications of nuclear science and technology. As the country with the fastest growth of nuclear energy in the world, China has a complete nuclear industrial chain, and the development of nuclear energy enjoys incomparable advantages. China cooperates with IAEA and holds the China-IAEA NEM School to share its experience and contribute its wisdom to the global nuclear energy development, and to personnel training of emerging nuclear energy countries.
This paper reports a case study from the China-IAEA NEM School which investigates the joint cultivation and training mode for young professionals who show managerial potentiality and inherent ability for future leadership positions in the field of nuclear energy and technology in IAEA’s Member States that plan to develop or are in the process of embarking upon a nuclear power programme. This study explores the school’s training system which is reflected in different aspects, i.e. training format, curriculum, and lecturers. A questionnaire survey is also conducted to analyze trainees’ evaluation of the school. The research findings are discussed in light of future developments and implications on young future leaders’ cultivation and training in the nuclear field in post COVID era.
Multi-Units Nuclear Power Plant Site Initial Event Filtration
Authors: Feng Wanxin , Zhao Runcai , Ding Shuxian , Yu Yu , Niu Fenglei 
Published: November 2022

Abstract
At present, the probabilistic safety assessment (PSA) method is mainly applied to a single unit, while actual nuclear power plants are usually multi-reactor sites. In the multi-unit level 1 probabilistic safety assessment study, the modeling workload is greatly increased. Also, it is necessary to consider the correlation between units, the probabilistic safety evaluation of multiple reactor sites is confronted with great challenges. Safety assessment of multi-unit sites should begin with a screening of the initial event, and not all events need to be analyzed by building an event tree. This paper described the classification status of initial events at multi-unit and calculated these events’ core damage frequency (CDF) upper and lower bounds. The upper limit of CDF is based on the assumption of complete dependence between units, and the lower limit is based on the assumption of complete independence between units. Taking a two-unit as an example, it screened the initial events and sorted out the characteristics of accidents. We assume that the time limit for simultaneous accidents of two units is 24 hours. The results show that the loss-of-offsite-power (LOOP), loss of heat trap and other events are suitable for modeling and analysis. In addition, given the analysis suggestions for other accidents combined with their characteristics. The analytical methods and results provide the basis for the multi-unit Probabilistic Safety Assessment modeling.
Can Infants Generalize Tool Use From Spoon to Rake at 18 Months?
Authors: Jeancolas Laetitia , Rat-Fischer Lauriane , O’Regan J. Kevin , Fagard Jacqueline 
Published: November 2022

Infants start to use a spoon for self-feeding at the end of the first year of life, but usually do not use unfamiliar tools to solve problems before the age of 2 years. We investigated to what extent 18-month-old infants who are familiar with using a spoon for self-feeding are able to generalize this tool-use ability to retrieve a distant object. We tested 46 infants with different retrieval tasks, varying the tool (rake or spoon) and the target (toy or food). The tasks were presented in a priori descending order of difficulty: rake–toy condition, then either spoon–toy or rake–food, and finally spoon–food. Then, the same conditions were presented in reverse order to assess the transfer abilities from the easiest condition to the most difficult retrieval task. Spontaneously, 18-month-old infants performed the retrieval tasks better with the familiar tool, the easiest task being when the spoon was associated with food. Moreover, the transfer results show that being able to use a familiar tool in an unusual context seems necessary and sufficient for subsequent transfer to an unfamiliar tool in the unusual context, and that early and repetitive training of self-feeding with a spoon plays a positive role in later tool use.
Does cardiovascular preparticipation screening cause psychological distress in athletes? A systematic review
Authors: Hill Braeden , Grubic Nicholas , Williamson Matthew , Phelan Dermot M , Baggish Aaron L , Dorian Paul , Drezner Jonathan A , Johri Amer M 
Published: November 2022

ObjectiveTo evaluate the psychological implications of cardiovascular preparticipation screening (PPS) in athletes.DesignSystematic review.Data sourcesMEDLINE, EMBASE, PubMed, CINAHL, SPORTDiscus, APA PsycInfo, Cochrane Library and grey literature sources.Study eligibility criteriaObservational and experimental studies assessing a population of athletes who participated in a cardiovascular PPS protocol, where psychological outcomes before, during and/or after PPS were reported.MethodsResults of included studies were synthesised by consolidating similar study-reported measures for key psychological outcomes before, during and/or after screening. Summary measures (medians, ranges) were computed across studies for each psychological outcome.ResultsA total of eight studies were included in this review (median sample size: 479). Study cohorts consisted of high school, collegiate, professional and recreational athletes (medians: 59% male, 20.5 years). Most athletes reported positive reactions to screening and would recommend it to others (range 88%–100%, five studies). Increased psychological distress was mainly reported among athletes detected with pathological cardiac conditions and true-positive screening results. In comparison, athletes with false-positive screening results still reported an increased feeling of safety while participating in sport and were satisfied with PPS. A universal conclusion across all studies was that most athletes did not experience psychological distress before, during or after PPS, regardless of the screening modality used or accuracy of results.ConclusionPsychological distress associated with PPS in athletes is rare and limited to athletes with true-positive findings. To mitigate downstream consequences in athletes who experience psychological distress, appropriate interventions and resources should be accessible prior to the screening procedure.PROSPERO registration numberCRD42021272887.