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The conversion of coal-fired power plants to nuclear power stations is a potential method for decarbonizing coal power and offers a pathway for low-carbon development in China's power industry. This paper focuses on retrofitting China's coastal coal-fired power stations and compares the potential nuclear reactor technologies for the retrofit: China's mainstream pressurized water reactor and the commercially operated fourth-generation high-temperature gas-cooled reactor (HTGR). The analysis compares the degree of matching between the two technologies and coal-fired power stations in terms of unit capacity, thermal system parameters, unit speed, structural dimensions, and weight, which significantly impact the retrofit scheme. The results indicate that HTGR is more compatible with coal-fired power plants and is recommended as the type of nuclear reactor technology to be retrofitted. The study selected the 210 MWe High-Temperature Gas-Cooled Reactor Pebble-Bed Module (HTR-PM) as the reactor technology for retrofitting a typical 300 MW class subcritical coal-fired unit. Based on the concept of subcritical parameters upgrading, the potential analysis and strategy study of retrofit is carried out in terms of the turbine, the main heat exchange equipment, the main pumps, and the main thermal system pipelines in the conventional island. The results indicate that the conventional island of the HTR-PM nuclear power plant has significant potential for retrofitting, which can be a crucial research direction for nuclear retrofitting of coal-fired power plants. [ABSTRACT FROM AUTHOR]

Nuclear reactors will face the problem of decommissioning at the end of their operating life due to the high radioactivity of reactor components and environmental safety considerations. The Heavy Water Research Reactor (HWRR) is the first large-scale research reactor to be decommissioned in China. The second phase of HWRR decommissioning involves the main components in the reactor block, so the radiation source terms and the radioactive waste level need to be evaluated before demolition and disposal. Based on the operating history, three-dimensional geometry, materials, and other information of the HWRR, the activity of radionuclides in the main components of HWRR is calculated and analyzed, and the MCNP/ORIGEN coupling scheme is utilized for theoretical analysis. The theoretical results indicate that 14C, 54Mn, 55Fe, 60Co, 63Ni, and 152Eu are the main radioactive nuclides. The total activity of radioactive nuclides was 2.36E + 15 Bq at the end of 2007, 4.27E + 13 Bq at the end of 2021, and 1.83E + 13 Bq at the end of 2025. Furthermore, local sampling and radiometric analyses based on the HPGe gamma-ray spectrometer are also performed to verify the theoretical results, the ratio of theoretical activity values to the measured activity of the experimental sample is within 2.5 times, so the theoretical results are conservative. According to the classification standards for radioactive waste, the inner shell, outer shell, cooling water tank, sand layer, and heavy concrete shielding layer are all low-level waste. These results and conclusions can serve as a reference for the second phase decommissioning of the HWRR and the subsequent disposal of radioactive waste. [ABSTRACT FROM AUTHOR]

All provinces of China respond to the central government, predict future carbon dioxide emissions, and formulate action plans detailing how the province intends to fulfill its target of carbon emission peaking before 2030. Based on the bottom‐up energy consumption prediction and top‐down goal verification, this paper constructs a set of regional carbon dioxide emission prediction methods. Compared to the traditional bottom‐up prediction method, this method could simplify the parameters while improving the prediction accuracy. This model is used to predict and analyze the process of carbon dioxide emission peaking in Zhejiang. The results show that the mean absolute percentage error of the retrospective prediction value is only 1.56%. Zhejiang will reach carbon dioxide emission peaking around 2029–2030, and the peak value will be 569.7 million tons. Different factors have different effects on the process of carbon dioxide emission peaking. There is a strong correlation between the peak time of carbon dioxide emission and the production time of major energy‐consuming projects in Zhejiang. Meanwhile, if the 16 nuclear reactors are not put into operation, Zhejiang will not be able to achieve the goal of carbon dioxide emission peaking. Besides, the basic data used in this model is mainly from the local statistical departments of the region. Thus, it can be applied to other provinces and regions conveniently. [ABSTRACT FROM AUTHOR]

The demand for the power grid system's capacity to undergo peak-shaving is increasing as the proportion of renewable energy rises. In China, nuclear power units usually only provide a base load operation in the view of safety and economic considerations, but they do not provide load adjustment services, which undoubtedly increases the pressure of grid load adjustment. In this paper, a novel flexibility load adjustment strategy of the CHP nuclear unit is studied, which is achieved by introducing the thermal storage tank (TST) into the Rankine cycle without changing the output of the nuclear reactor. The AP1000 pressurized water reactor nuclear power unit for combined heat and power is taken as an example, and the thermodynamic model is established through the water vapor equation. Furthermore, the reference system is simulated for the goal of minimizing the imbalance between power supply and demand, and the flexibility–environment–economy benefits are evaluated. The results show that the heat storage/release of the TST may achieve power output flexible adjustment of the nuclear unit, and the power imbalance of the reference energy system is reduced from 1107.99 MWh to 457.24 MWh, a reduction of 58.73%. The introduction of a 600 MWh TST can enable the reference unit to contribute 335 MWh of peak electricity within the reference day. From the perspective of replacing the power generation output increment of coal-fired power units with equal amounts, it can achieve a reduction of 106.09 tons of coal consumption in the case day, which means that 277.73 tons of CO2 emissions can be reduced. The profit of the reference unit can be improved by CHY 70,125 via participating in load adjustment in the case day if following the time-of-use electricity price. [ABSTRACT FROM AUTHOR]

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Conventional hydrogen production technologies mostly fossil fuels as energy and material basis. The rapid development of nuclear energy in recent years offers a new opportunity. Clean electricity and process heat generated by nuclear reactors can provide energy for hydrogen production, effectively reducing the environmental burden. This study used life cycle assessment (LCA) method to sort out the inputs and outputs of the nuclear hydrogen production processes and analyze the environmental impacts based on local data in China. In this study, we constructed frameworks for two nuclear energy-based processes and created four different scenarios to compare the effect of energy efficiency. Six indicators were used to quantify the environmental impact. The results showed that: (1) electrolysis cell manufacturing and spent fuel disposal generate the largest emissions in hydrogen production. (2) S–I cycle is sensitive to heat transfer efficiency, while high-temperature electrolysis is more sensitive to power generation efficiency; (3) The environmental impact of high-temperature electrolysis (without carrier gas) is slightly lower than that of S–I cycle, but the advantage will disappear as energy efficiency increases. At present, high-temperature electrolysis offers a clean alternative to conventional technologies for hydrogen energy and hydrogen economy. The S–I cycle might have a better prospect in the future. Our study results will provide a scientific assessment of the possibilities of developing nuclear energy for hydrogen production in China and help to make some decisions and policies. [Display omitted] • Nuclear hydrogen production using HTR was evaluated based on life cycle assessment. • Six indicators were used to quantify environmental impact of H 2 production processes. • We categorized all phases and screened out the main environmental factors and sources. • Four scenarios were created to compare the effect of energy efficiency on systems. • The environmental impact of high-temperature electrolysis was lower than S–I cycle. [ABSTRACT FROM AUTHOR]

The uncertainty quantification is an indispensable part for the validation of the nuclear safety best-estimate codes. However, the uncertainty quantification usually requires the combination of statistical analysis software and nuclear reactor professional codes, and it consumes huge computing resources. In this paper, a design method of coupling interface between DAKOTA Version 6.16 statistical software and nuclear reactor professional simulation codes is proposed, and the integrated computing workflow including interface pre-processing, code batching operations, and interface post-processing can be realized. On this basis, an integrated framework of uncertainty quantification is developed, which is characterized by visualization, convenience, and efficient computing. Meanwhile, a typical example of small-break LOCA analysis of the LOBI test facility was used to validate the reliability of the developed integrated framework of uncertainty quantification. This research work can provide valuable guidance for developing an autonomous uncertainty analysis platform in China. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Relaciones Internacionales (1699-3950) is the property of Autonomous University of Madrid, Spain, International Relations Studies Group (GERI) Law Faculty and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nuclear Safety is the property of Nuclear & Radiation Safety Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently, international nuclear fission reactors producing medical isotopes face the problem of shutdown and maintenance, decommissioning, or dismantling, while the production capacity of domestic research reactors for medical radioisotopes is inadequate, and the supply capacity for medical radioisotopes faces major challenges in the future. Fusion reactors are characterized by high neutron energy, high flux density, and the absence of highly radioactive fission fragments. Additionally, compared to fission reactors, the reactivity of the fusion reactor core is not significantly affected by the target material. By building a preliminary model of the China Fusion Engineering Test Reactor (CFETR), a Monte Carlo simulation was performed for particle transport between different target materials at a fusion power of 2 GW. The yields (specific activity) of six medical radioisotopes (14C, 89Sr, 32P, 64Cu, 67Cu, and 99Mo) with various irradiation positions, different target materials, and different irradiation times were studied, and compared with those of other high-flux engineering test reactors (HFETR) and the China Experimental Fast Reactor (CEFR). The results show that this approach not only provides competitive medical isotope yield, but also contributes to the performance of the fusion reactor itself, e.g., tritium self-sustainability and shielding performance. [ABSTRACT FROM AUTHOR]

A new module for the AZtlan Nodal HEXagonal (AZNHEX) code, which is part of the AZTLAN Platform, was recently developed based on the Simplified Spherical Harmonics (SPL) scheme to deal with the challenges presented in small fast reactor cores, such as the China Experimental Fast Reactor (CEFR), with high leakage and significant scattering effects. For the verification and validation process, we generated nodal homogenized macroscopic cross-sections (XS) through a full heterogeneous core model using the stochastic code SERPENT and subsequently, these XS were employed in AZNHEX. To verify the SPL implementation, several mesh sensitivity exercises were performed demonstrating that the SPL module was implemented successfully. Furthermore, to validate the code with this new implementation, we modeled some exercises contained in the CEFR benchmark with AZNHEX and compared the results with the experimental data available. The final results show a great improvement compared with the original diffusion solver reducing the deviations significantly from experimental data. In conclusion, it is shown and discussed the relevance of improved numerical models (transport approximations instead of diffusion) for the deterministic calculations of small fast reactors [ABSTRACT FROM AUTHOR]

The Taishan Antineutrino Observatory (TAO or JUNO-TAO) is a satellite detector for the Jiangmen Underground Neutrino Observatory (JUNO). JUNO aims at simultaneously probing the two main frequencies of three-flavor neutrino oscillations, as well as their interference related to the mass ordering, at a distance of ~53 km from two powerful nuclear reactor complexes in China. Located near the Taishan-1 reactor, TAO independently measures the antineutrino energy spectrum of the reactor with unprecedented energy resolution. The TAO experiment will realize a neutrino detection rate of about 2000 per day. In order to achieve its goals, TAO is relying on cutting-edge technology, both in photosensor and liquid scintillator (LS) development which is expected to have an impact on future neutrino and Dark Matter detectors. In this paper, the design of the TAO detector with a special focus on calorimetry is discussed. In addition, an overview of the progress currently being made in the R&D for a photosensor and LS technology in the frame of the TAO project will be presented. [ABSTRACT FROM AUTHOR]

Japan was struck by a massive earthquake that triggered a tsunami in March 2011, which led to a severe nuclear accident at the Fukushima Daiichi Nuclear Power Plant of the Tokyo Electric Power Company. Now, more than 10 years later, it is widely acknowledged that the civil nuclear industry is of great importance in reducing greenhouse gas emissions, improving natural environmental quality, and safeguarding national energy security. Nanomaterials and nanotechnologies, which have gained wide consideration in recent years, have shown a wide variety of application potentials in the future nuclear energy system. Thus, China has been developing its civil nuclear industry throughout the years, despite the nuclear accident in Fukushima, Japan. As a result, China is currently one of the countries with the most nuclear power plants. However, due to the potential radioactive risk, the public has an instinctive fear of civil nuclear development. To alleviate the public's antinuclear sentiment, the Nuclear Safety Law was formally implemented in 2018, and Measures for Disclosure of Nuclear Safety Information were issued by the Ministry of Ecology and Environment of China in 2020, both stipulating that the public has the right to obtain information about nuclear safety and be involved in related activities. The purpose of such legislation is to eliminate the public's doubts and phobia about the development of the civil nuclear industry. However, challenges still exist. Although such suggestions have been proposed, such as information disclosure and social involvement should begin as early as the siting of such nuclear facilities, mechanisms to provide sufficient compensation to the public living near nuclear facilities should be established, and these suggestions still have not been applied in the law of China and either not been practiced exactly so far. So, even though all the suggestions have strong feasibility themselves under today's circumstances in China, it is not easy to judge the effectiveness of these suggestions until they are fully practiced. It is the biggest problem of existing works in this paper. To highlight the serious problems in information disclosure and public involvement in the siting and construction of civil nuclear facilities, several case studies were investigated as the major methodology in this research. Moreover, a legislation study was used to analyze the current content of related legislation and regulations. A qualitative methodology was also adopted to summarize the legal problems surrounding information disclosure and social involvement during the siting and construction of civil nuclear facilities. Information disclosure and public participation still face several obstacles in China, even though laws and regulations guarantee people the right to access available information and take part in pertinent decision-making. This is particularly true when it comes to the siting and construction of civil nuclear facilities. Thus, in the last several years, several antinuclear incidents have been initiated by the public due to a lack of information and mechanisms to participate. According to the examined cases, information disclosure and public involvement are still not sufficient during the siting of nuclear facilities. A relevant compensation mechanism for people living around nuclear facilities has not been established, and public education on basic nuclear safety is lacking. Therefore, public involvement cannot be completely realized. To ensure information disclosure and public involvement in civil nuclear facilities, this article proposes that information disclosure and social involvement begin as early as the siting of such facilities. Furthermore, operators of nuclear facilities and local governments should establish mechanisms to provide sufficient preventive compensation to the public living near nuclear facilities and attempt to popularize the science of nuclear safety to avoid public misunderstanding. [ABSTRACT FROM AUTHOR]

The vertical water-lubricated bearing technology widely used in the third generation pressurized water reactor nuclear power plant is one of the key points restricting the development of nuclear power in China.Therefore,it is of important engineering value to establish a vertical bearing test bench for relevant tests. A design scheme of vertical water-lubricated tilting pad bearing test bench was proposed,which included loading-drive system,lubrication-seal system and measurement system.By comparing the difference of bearing restraint between horizontal bearing test bench and vertical bearing test bench during loading,the floating bearing restraint mechanism scheme suitable for vertical bearing test bench was given.According to the similar criteria,the vertical water lubricated tilting pad bearing of AP1000 nuclear main pump was designed in a reduced scale, and bearing test pieces suitable for test and research were designed under the condition that the requirements of Summerfeld number,width diameter ratio and clearance ratio were met.The test results show that the developed vertical four-pad tilting pad water lubricated bearing test bench can measure the bearing surface temperature, water supply pressure, static load, water film pulsating pressure, rotating shaft whirl under different rotational speeds and loading excitation conditions.The operating state of the test bench is stable,which can meet the research requirements of dynamic and static characteristics of vertical water-lubricated tilting pad bearings. [ABSTRACT FROM AUTHOR]

In recent years, the state has put forward a grand plan to develop nuclear power in order to control environmental pollution and carbon emissions. In nuclear power plants, mechanical seals for reactor coolant pump play an important role in nuclear power safety production. However, China cannot independently produce such mechanical seals, and they are blocked by foreign related technologies, which has seriously affected China's nuclear power development plan and the overall safety of China's nuclear power operation. Under this background, this paper studies the friction performance of the shaft seal of the reactor coolant pump, uses the sensor to obtain the data of friction factors such as low-pressure leakage, effectively monitors the low-pressure leakage through calculation and simulation modeling, truly reflects the operating state of the reactor coolant pump, and provides a new research direction and experimental basis for further analysis of the friction performance of the shaft seal of the reactor coolant pump. The results show that under the joint action of the pressure difference and the force generated by the deformation of the moving ring plate, the cone angle formed on the seal end face is 1300.9 μ convergence gap of rad. When the inlet water temperature is 65°C, the leakage rate is 1867.8 L/h. The deformation of the moving ring deformation ring plate can hinder the increase of the deformation cone angle of the moving ring. The greater the thickness of the moving ring deformation ring plate, the greater the seal leakage rate. The inlet temperature of the sealing medium and the friction performance of the material also have an impact on the sealing performance. [ABSTRACT FROM AUTHOR]

Copyright of Nuclear Safety is the property of Nuclear & Radiation Safety Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Based on MATLAB/Simulink simulation platform, a simulation model of nuclear power unit is built and verified. • According to two typical faults in power system, the influence of grid faults on the operation characteristics of nuclear power units is studied. • According to the fault condition of power system, the influence of the difference coefficient of primary frequency modulation and frequency modulation dead zone on the operation characteristics of nuclear power units is studied. • The influence of overspeed protection controller on nuclear power units is analyzed and an optimized overspeed protection scheme is established in view of the load step drop condition caused by failure of fault cutting. With the development of nuclear power industry in China, the proportion of nuclear power generation in the total power generation is constantly rising. As the power system is always faced with the threat of faults of different degrees, these faults will not only affect the power quality, but also are potential risks for nuclear power units with high safety requirements. Therefore, it is necessary to study the influence of typical power system faults on nuclear power units. The corresponding control strategies for typical power system fault conditions are studied. The primary frequency regulation (PFR) parameter optimization scheme and overspeed protection optimization scheme proposed in this paper can effectively solve the frequency disturbance and steam turbine overspeed problems caused by power system faults. The research results can provide reference for large PWR nuclear power units to deal with typical power system faults, and have certain engineering application value. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China will triple the number of nuclear power plants it has in operation by 2020 according to official plans, and the country’s nuclear fleet will increase 20-fold by 2050 under some not-yet-approved proposals. But how and where will China get the uranium to fuel them all? Will China need to resort to breeder reactors and reprocessing, with all the proliferation problems they incur? Or is there another way? The author suggests that between China’s domestic uranium mining, uranium purchased on the international market, and uranium mined by Chinese-owned companies overseas, China could meet even the most ambitious target, thus avoiding the troublesome and dangerous path of reprocessing. [ABSTRACT FROM PUBLISHER]

Tritium with different chemical forms have different effects on the human body. In tritium migration and conversion, soil plays a significant role. In this study, our samples are from the surrounding environment of the Qinshan Nuclear Power Plant, in addition, Qinshan Phase III Nuclear Power Plant is the only heavy water reactor nuclear power plant (CANDU type, 700 MWe) in China. Both tritiated water (HTO) and non-exchangeable organically bound tritium (NE-OBT) were measured at the surface soil (0–2 cm) at 8 sampling sites and their depth profiles in the subsurface 30 cm of soil in two sampling sites around Qinshan Nuclear Power Plant in 2015, 2016 and 2018. The distribution analysis showed the further away from the nuclear power plant, the lower activity concentration of HTO at the surface soil. Also, in the depth profile, the HTO activity concentration decreased as the depth increase. Through soil analysis at different depths of sampling points A and D, it is concluded that the activity concentration of NE-OBT is the largest in the surface soil of the selected sampling points, which is similar to the HTO of most sampling points. [ABSTRACT FROM AUTHOR]

The Chinese government promotes nuclear energy development in the context of mitigating climate change. However, the large-scale development is still facing challenges related to the knowledge gap among the general public and the potential "not-in-my-back-yard" objection. Based on a representative national survey, we analyze Chinese people's knowledge and perceptions of nuclear energy and estimate their willingness-to-accept the potential risks of new nuclear programs in neighborhoods via the Contingent Valuation Method. Generally, more than half of people do not know anything about nuclear energy. The main factors influencing public knowledge are identified, such as the residential distance to existing nuclear power stations and the frequency of internet use. Moreover, approximately 12% of individuals with some knowledge seem to be willing to accept new nuclear power plants in their neighborhoods with no compensation needed. Specifically, the perceptions of nuclear risks and pollution from fossil fuels are significant factors influencing people's acceptance of nuclear energy. Although public knowledge does not directly influence acceptance, more knowledge seems to reduce risk perception and increase benefit perception. The residential distance to exiting nuclear stations has limited effects on people's acceptance of newly planned nuclear programs for those living in the same county with some knowledge. In general, a typical Chinese household is willing to accept USD $5.66 every month or USD $67.97 every year to bear the potential risks of the new nuclear program in neighborhoods. Significant practical implications that can be transferable to other new energy technologies and countries or regions are provided. • Chinese people's knowledge of and willingness to accept nuclear energy are analyzed. • More than half of Chinese people do not know about nuclear energy at all. • Factors influencing public knowledge include residential area, internet use, etc. • The WTA to bear risks of nuclear plant for a household is USD $5.66 every month. • Nuclear risk perception and benefit perception significantly influence people's WTA. [ABSTRACT FROM AUTHOR]

Fine flow and heat transfer characteristics are critical to nuclear reactor safety. However, a comprehensive CFD calculation of the entire reactor core requires substantial computing resources, restricting the research domain's scope. To address this issue, we propose a Distributed Parallel (DP) computing scheme, tailored specifically for reactor cores using plate-type fuel assemblies. This study focuses on the thermal-hydraulic calculation of the large domain of a reactor core utilizing plate-type fuel assembly, based on the Computational Fluid Dynamics (CFD) method. This innovative solution enables the completion of extensive domain CFD calculations using modestly equipped personal workstations (8 cores, 128G RAM), which traditionally would require supercomputing platforms. To verify the distributed-parallel computing technique, it is successfully applied to all standard, full-length fuel assemblies in the China Advanced Research Reactor (CARR). In the result analysis, it was observed that detailed results could be obtained with reduced computational resources, demonstrating a significant breakthrough for CFD engineering analysis. [ABSTRACT FROM AUTHOR]

The article focuses on the potential jeopardy facing the 44-year-old U.S.-China scientific cooperation agreement due to rising tensions between the two countries. Topics discussed include the extension of the agreement for six months, the need to address issues like intellectual property rights and data sharing, and the debate over the agreement's impact on national security and research collaboration.

• Evaluation of decay heat removal systems of FHR during thermal-hydraulic transient was performed. • Heat removal performances of FHR systems are investigated. • FHR's decay heat removal system shows sufficient heat removal capability to avoid catastrophic accidents. The Fluoride-salt-cooled High-temperature Reactor (FHR) is one of the Generation IV nuclear reactor concepts being investigated mainly in the U.S. and China. Liquid salt with high boiling point of over 1400 °C is used as a coolant and its baseline fuel is the graphite-matrix coated-particle fuel developed for high-temperature gas-cooled reactors. To establish advanced safety systems in FHR, passive decay heat removal system which utilizes fluid's natural circulation is considered. Three systems are proposed: Direct Reactor Air Cooling System (DRACS), Reactor Vessel Air Cooling System (RVACS), and Silo Cooling System (SCS). Although these three safety systems were previously developed for other types of reactors, their heat removal performances need to be evaluated for the FHR plant. The current study provides evaluation of decay heat removal systems of FHR during thermal-hydraulic transient. In addition, FHR's grace period to start the reactor cooling was determined under the condition where no operable heat removal systems are available. The current study shows that FHR's decay heat removal systems possess sufficient heat removal capability to avoid catastrophic accidents. The construction of Fluoride-salt-cooled High-temperature Test Reactor (FHTR) is currently being planned and its development is a key step to realize the commercialization in near future. This study provides performance evaluation of decay heat systems for FHTR under thermal-hydraulic transient, and also suggests the adequate operation procedure suitable for FHTR to avoid a severe accident. [ABSTRACT FROM AUTHOR]

♦ DBD have been engaging with small modular reactor (SMR) & advanced modular reactor (AMR) vendors, looking to collaborate and test the viability of future nuclear power through a range of SMR/AMR programmes. ♦ The article summarises the nuclear renaissance and the next generation of reactors, providing an overview of where the UK has been and where we are likely to be heading, in terms of future nuclear reactor designs, and the challenges associated with getting there. ♦ DBD Limited, in conjunction with the Institute of Nuclear and New Energy Technology (INET), Tsinghua University in Beijing, China, have put forward the UK-High-Temperature Reactor - Pebble-bed Modular (UK-HTR-PM) design concept as one of the eight contractors working on Phase 1 of the BEIS AMR Feasibility and Development project, as part of the Nuclear Sector Deal. ♦ Looking to the future, DBD have noted the considerations to develop the UK-FITR-PM further, the positive impact this new reactor aims to deliver and the real value it represents for a number of purposes. [ABSTRACT FROM AUTHOR]

The article offers information on fission energy and other sources of energy. The problem of how to suffice the increasing demand for energy in the world is attracting great concern. In the United States, the creation of the atomic energy reactor initialized the strategy to counteract this problem. Competent team of scientists worked in laboratories which were well aided by the U. S. government. This technological innovation spread to other countries. However in some countries like the Soviet Union, the United Kingdom, France, and China, atomic bombs were manufactured, while in other countries atomic reactors were built for peaceful use.

The article presents the first part of a two-part series about the views of Chinese on nuclear proliferation. According to the Chinese, nuclear weapons can only be finally eliminated and total nuclear disarmament achieved after a number of additional countries get nuclear weapons. From the start, Chinese recognized from the start the danger to them created by the American monopoly of first atomic and then hydrogen weapons, but they were relieved by the Soviet development of weapons capabilities.

• Robust and accurate prediction of PWR safety parameters is provided by TCNN. • Sparse connections greatly improve the global awareness of the mode. • Convolutional kernels effectively enhance local feature extraction ability. • Basic blocks consist of residual connections prevent the gradient loss. Accurate forecasts for pressurized water reactor safety parameters are essential to ensure the safe operation of nuclear reactors. Potential of artificial neural networks on this task is limited owing to the lack of extracting the core location information. Sparse connections have unique advantages in discovering correlation between neighboring components and convolution kernels are designed to deal with two-dimensional information. In this paper, topological information embedded convolutional neural network (TCNN) was firstly established and utilized. This model enhanced the ability of fusing location features and component attributes through sparse connections and convolution layers. Datasets of China's Qinshan Nuclear Power Plant Phase II PWR was used to evaluate the performance of TCNN. Comparative and ablation experiments demonstrated that TCNN has superiority in working as efficient predictor for pressurized water reactor safety parameters, indicating that the proposed model promoted the digitalization of nuclear power plants. [ABSTRACT FROM AUTHOR]

• A novel approach to nuclear condition monitoring using an R-vine copula is presented. • The developed framework can detect and diagnose the fault without any prior or detailed information. • Comparisons with other multivariate statistical tools highlight the superiority of the proposed method. • It provides new insight into multivariate probabilistic safety assessment in nuclear plants. Safety assessment of nuclear plants is pivotal for preventing an accident. The fault detection and diagnosis (FDD) module is crucial for ensuring plant safety since it is helpful in detecting any abnormal deviation from the normal operating condition and diagnosing the root cause(s) or faulty variables to restore the operation in the normal mode. The current work proposes a multivariate probabilistic framework using an R-vine copula for nuclear plants' FDD. Instead of feature extraction, it uses variables' dependence descriptions for monitoring. This tool does not require detailed fault information to provide diagnosis reports for distinct fault types – a common requirement for machine learning models. At the same time, unlike most multivariate statistical tools, it can capture data nonlinearity and non-Gaussianity and generate useful diagnosis results without the help of other tools. The proposed framework is tested and validated to four fault scenarios generated in the China Lead-based Reactor (CLEAR) platform. A detailed comparison with the other multivariate statistical tools: principal component analysis (PCA), independent component analysis (ICA), and kernel principal component analysis (KPCA), suggests that the R-vine model can provide a better monitoring mechanism. The current work will provide a new insight into multivariate probabilistic safety assessment in nuclear plants using vine copula models. [ABSTRACT FROM AUTHOR]

Radiobiology assesses the biological hazards of exposure to radioactive substances and nuclear radiation. This article explores the history of radiobiology in twentieth-century China by examining the overlapping of radium research and biophysics, from roughly the 1920s Nationalist period to the 1960s Communist period; from the foreign purchase of radium by the Rockefeller Foundation's China Medical Board during the Republican era, to the institutional establishment of radiobiology as a subset of biophysics in the People's Republic. Western historiography of radiobiology highlights the connection between the military development of nuclear weapons and the civilian use of radiation in biology, as well as the international export of radioisotopes and nuclear reactors. Considering the exclusion of China from Western atomic diplomacy, I argue that the study of the Chinese history of bomb-making and radiobiology is necessary not just to fill an existing knowledge gap, but more importantly to elucidate the influence of the Chinese nuclear weapons program and Cold War atomic politics on Chinese life-science enterprises. Through examining the formational history of the radiobiology program in China, I hope to shed light on the implications of the atomic age for Chinese biology in the twentieth century. [ABSTRACT FROM AUTHOR]

Since nuclear power is able to produce significant amounts of energy for a small amount of fuel, this method has recently attracted attention of most countries. In the present study, we seek to investigate the problems associated with nuclear energy in China. China is ranked 11th in terms of nuclear power generation, and it is currently producing 8587 MW of nuclear power with its 11 nuclear reactors. However, China supplies only 1.9% of its electricity from nuclear energy and it is much lower than the global average of 16%, because less than 1% of world’s uranium reserve exists in China. Currently, China is heavily dependent on imports from countries such as Russia and Australia to achieve primary fuels. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on the collaboration of the governments of China and the China in securing bomb grade reactor fuel which rekindled the relationship between the two nation's nuclear scientists. Overview of the nuclear reactor located at the Ghana Research Reactor and the cooperation of the said scientists in removing the high enriched uranium fuel at the facility is provided. The advantage of the initiative which ended the cold war between two countries is mentioned.

China, as the world leader in constructing new nuclear reactors, has yet to resolve either its short-term spent nuclear fuel (SNF) problems or the challenge of long-term final disposition. While it may be several decades before the fuel disposition question will be resolved, the near-term problem of establishing adequate interim SNF storage is much more acute. The state of nuclear-reactor development in China presents an opportunity to address SNF management issues at an early stage. This article outlines a scenario-based study aiming to inform SNF interim storage policy even while the final disposition solution remains uncertain. We describe a comprehensive model and show results from a crucial subset of issues—the logistics of SNF accumulation, transportation, and storage—and describe simple steps to strengthen the SNF storage system. Finally, we forecast when the current method of SNF disposition could break down and offer recommendations and guidance for further study. [ABSTRACT FROM PUBLISHER]