检索结果-南通市图书馆

Journal of Advanced Ceramics 2024年第8期13卷 1143-1152页

作者： Jingwen Xi Linlin Liu Hongwei Qiao Jiacheng Luo Xin Su Xin Zhao Yugen Xu Hao Chen Zhi Tan Jianguo Zhu nuclear power institution of china Chengdu 610213China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China

Enhancing the piezoelectricity of CaBi_(4)Ti_(4)O_(15)(CBT)ceramics is crucial for improving their application potential in high-temperature piezoelectric ***,we propose a strategy involving the introduction of larger Na/Bi ions at the A-site,effectively inhibiting the tilt of oxygen octahedra and flattening the potential energy *** flattening enhances the variation in polarization under external ***,substituting Nb/Mn at the B-site increases the deviation between positive and negative ionic centers,leading to stronger spontaneous polarization,while the induced defect dipoles restrict oxygen vacancy migration and increase the direct current resistivity(ρ_(dc)).The flattened potential energy profile and increased spontaneous polarization significantly enhance the overall performance of cBT ceramics,with the piezoelectric constant(d_(33))reaching 25 pC/N when the Curie temperature(Tc)=752℃.Piezoresponse force microscopy(PFM)and transmission electron microscopy(TEM)revealed submicron-long rectangular domains and nanoscale domains in the modified composition,indicating a high density of domain *** study presents an effective approach for enhancing the piezoelectric properties of bismuth layered-structured ferroelectrics(BLSFs),thereby improving the application potential of BLSFsathightemperatures.

关键词： piezoelectricity bismuth layered-structured ferroelectrics(BLSFs) potential energy profile spontaneous polarization high temperatures

Modeling and Simulation of Lithium Vacuum Evaporation Process Using COMSOL Multiphysics

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第1期33卷 86-100页

作者： LIAN Xuexin ZHONG Dawen Beijing Key Laboratory of Passive nuclear power Safety and Technology North China Electric Power UniversityBeijing 102206China

Based on the COMSOL Multiphysics simulation software,this study carried out modeling and numerical simulation for the evaporation process of liquid metal lithium in the vacuum free molecular flow *** motion of lithium atoms in the evaporation process was analyzed through a succession of *** on the available experimental values of the saturated vapor pressure of liquid metal lithium,the relationship between saturated vapor pressure and temperature of liquid lithium in the range of 600 K-900 K was obtained.A two-dimensional symmetric model(3.5 mm×20 mm) was established to simulate the transient evaporation process of liquid lithium at wall temperatures of 750 K,780 K,800 K,810 K,825 K,and 850 K,*** effects of temperature,the evaporation coefficient,back pressure,and length-to-diameter ratio on the evaporation process were studied;the variation trends and reasons of the molecular flux and the pressure during the evaporation process were *** the same time,the evaporation process under variable wall temperature conditions was *** research made the evaporation process of liquid lithium in vacuum molecular flow clearer,and provided theoretical support for the space reactor and nuclear fusion related fields.

关键词： free molecular flow saturated vapor pressure vacuum evaporation liquid lithium metal

Development of CONTHAC-3D and hydrogen distribution analysis of HPR1000

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2024年第2期35卷 210-221页

作者： Hui Wang Jing-Jing Li Yuan Chang Gong-Lin Li Ming Ding china nuclear power Engineering Co.LTD. Beijing 100084China Fundamental Science on nuclear Safety and Simulation Technology Laboratory Harbin 100049China

An in-house code,CONTHAC-3D,was developed to calculate and analyze thermal-hydraulic phenomena in containments during severe ***-3D is a three-dimensional computational fluid dynamics code that can be applied to predict gas flow,diffusion,and steam condensation in a containment during a severe hypothetical accident,as well as to obtain an estimate of the local hydrogen concentration in various zones of the ***-3D was developed using multiple models to simulate the features of the proprietary systems and equipment of HPR1000 and ACP100,such as the passive cooling system,passive autocatalytic recombiners and the passive air cooling *** validate CONTHAC-3D,a GX6 test was performed at the Battelle Model Containment *** hydrogen concentration and temperature monitored by the GX6 test are accurately predicted by ***,the hydrogen distribution in the HPR1000 containment during a severe accident was *** results show that the hydrogen removal rates calculated using CONTHAC-3D for different types of PARs agree well with the theoretical values,with an error of less than 1%.As the accident progresses,the hydrogen concentration in the lower compartment becomes higher than that in the large space,which implies that the lower compartment has a higher hydrogen risk than the dome and large space at a later stage of the *** amount of hydrogen removed by the PARs placed on the floor of the compartment is small;therefore,raising the installation height of these recombiners appropriately is ***,we do not recommend installing all autocatalytic recombiners at high *** study findings in regard to the hydrogen distribution in the HPR1000 containment indicate that CONTHAC-3D can be applied to the study of hydrogen risk containment.

关键词： Hydrogen risk mitigation Pressurized water reactor HPR1000 Thermal hydraulic CONTHAC-3D

Effects of interstitial cluster mobility on dislocation loops evolution under irradiation of austenitic steel

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2024年第8期35卷 69-78页

作者： Xin‑Hua Yan Lu Sun Du Zhou Teng Xie Chang Peng Ye‑Xin Yang Li Chen Zhen‑Feng Tong North china Electric power University Beijing 102206China china nuclear power Operations Co. LtdShenzhen 518000China

The evolution of dislocation loops in austenitic steels irradiated with Fe^(+)is investigated using cluster dynamics(CD)simulations by developing a CD *** CD predictions are compared with experimental results in the *** number density and average diameter of the dislocation loops obtained from the CD simulations are in good agreement with the experimental data obtained from transmission electron microscopy(TEM)observations of Fe~+-irradiated Solution Annealed 304,Cold Worked 316,and HR3 austenitic steels in the *** CD simulation results demonstrate that the diffusion of in-cascade interstitial clusters plays a major role in the dislocation loop density and dislocation loop growth;in particular,for the HR3 austenitic steel,the CD model has verified the effect of temperature on the density and size of the dislocation loops.

关键词： Cluster dynamics Dislocation loops In-cascade interstitial clusters Austenitic steels

Response characteristics of PWR primary circuit under SBLOCAs considering steam bypass discharging

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2024年第6期35卷 189-201页

作者： Shuai Yang Xiang-Bin Li Yu-Sheng Liu Jia-Ning Xu De-Chen Zhang School of nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Passive Safety Technology for nuclear Energy Beijing 102206China nuclear and Radiation Safety Center MEPBeijing 100084China

Small-break superposed station blackout(SBO)accidents are the basic design accidents of nuclear power *** the condition of a small break in the cold leg,SBO further increases the severity of the accident,and the steam bypass discharg-ing system(GCT)in the second circuit can play an important role in guaranteeing core *** explore the influence of the GCT on the thermal-hydraulic characteristics of the primary circuit,RELAP5 software was used to establish a numerical model based on a typical pressurized water reactor nuclear power *** different small breaks in the cold-leg super-posed SBO were selected,and the impact of the GCT operation on the transient response characteristics of the primary and secondary circuit systems was *** results show that the GCT plays an indispensable role in core heat removal during an accident;otherwise,core safety cannot be *** GCT was used in conjunction with the primary safety injection system during the placement *** the break diameter was greater than a certain critical value,the core cooling rate could not be guaranteed to be less than 100 K/h;however,the core remained in a safe state.

关键词： Steam bypass discharging Pressurized water reactor SBLOCA Numerical simulation

Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1275-1289页

作者： Qian Li Zi-Jie Lin Liu Yang Yue Wang Yue Li Wei-Hua Cai Laboratory of Thermo-Fluid Science and nuclear Engineering Northeast Electric Power UniversityJilin132000JilinChina School of Energy and power Engineering Northeast Electric Power UniversityJilin132000JilinChina

The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 *** simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow *** results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were *** calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So hea

关键词： Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis

Fully-light vector tetraquark states with explicit P-wave via QCD sum rules

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第3期48卷 25-38页

作者：辛琦王志刚 Department of Physics North China Electric Power UniversityBaoding 071003China School of nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China

In this study,we apply the QCD sum rules to investigate the vector fully-light tetraquark states with an explicit P-wave between the diquark and antidiquark *** observed that the Cγα⊗↔∂μ⊗γαC(or Cγα⊗↔Dμ⊗γαC)type current with fully-strange quarks couples potentially to a tetraquark state with a mass 2.16±0.14GeV,which supports assigning Y(2175)/ϕ(2170)as the diquark-antidiquark type tetraquark state with JPC=1−−.The qsˉqˉs and ssˉsˉs vector tetraquark states with the structure Cγμ⊗↔∂α⊗γαC+Cγα⊗↔∂α⊗γμ(or Cγμ⊗↔Dα⊗γαC+Cγα⊗↔Dα⊗γμ)are consistent with X(2200)and X(2400),respectively,which lie in the region from 2.20 to *** central values of the masses of the fully-strange vector tetraquark states with an explicit P-wave are approximately 2.16−3.13GeV(or 2.16−3.16GeV).Predictions for other fully-light vector tetraquark states with and without hidden-strange are also presented.

关键词： fully-light tetraquark state QCD sum rules

High-resolution neutronics model for ^(238)Pu production in high-flux reactors

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2024年第5期35卷 226-236页

作者： Qing-Quan Pan Qing-Fei Zhao Lian-Jie Wang Bang-Yang Xia Yun Cai Jin-Biao Xiong Xiao-Jing Liu School of nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux *** filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy *** burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme *** three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were *** neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.

关键词： ^(238)Pu Neutronics model High-flux reactor Spectrum resolution Spectrum optimization

Application of a microscopic optical potential of chiral effective field theory in (p, d) transfer reactions

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2024年第1期35卷 134-144页

作者： Yi-Ping Xu Si-Lu Chen Dan-Yang Pang School of nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China School of Physics Beihang UniversityBeijing 100191China

The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave *** target nuclei included both stable and unstable nuclei,and the incident energies reached 200 *** results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 ***,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive *** average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 ***,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca.

关键词： Microscopic optical model potential (p,d)transfer Spectroscopic factors

Systematic investigation of nucleon optical model potentials in(p,d)transfer reactions

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第7期48卷 168-175页

作者：陈思璐刘子旋张智续瑞瑞庞丹阳许祎萍 School of nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China china nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Physics Beihang UniversityBeijing 100191China

The consistent three-body model reaction methodology(TBMRM)proposed by *** et al.[***.C 69,064313(2004);***.C 73,044608(2006);***.C 75,064320(2007)],which includes adopting the simple zero-range adiabatic wave approximation,constraining the single-particle potentials using modern Hartree-Fock calculations,and using global nucleon optical model potential(OMP)geometries,are widely applied in systematic studies of transfer *** this study,we investigate the influence of different nucleon OMPs in extracting spectroscopic factors(SFs)from(p,d)*** study covers 32 sets of angular distribution data of(p,d)reactions on four targets and a large range of incident energies(20-200 MeV/nucleon).This study uses two semi-microscopic nucleon OMPs,i.e.,Jeukenne,Lejeune,and Mahaux(JLM)[***.C 16,80(1977);***.C 58,1118(1998)]and CTOM[***.C 94,034606(2016)],and a pure microscopic nucleon potential,i.e.,WLH[***.127,182502(2021)].The results are compared with those using the phenomenological global optical potential KD02[***.A 713,231(2003)].We find that the incident energy dependence of spectroscopic factors extracted from(p,d)reactions is evidently suppressed when microscopic OMPs are employed for ^(12)C,^(28)Si,and *** addition,spectroscopic factors extracted using the systematic microscopic optical potential CTOM based on the Dirac-Brueckner-Hartree-Fock theory are more in line with the results obtained from(e,e′p)measurements,except for 16O and ^(40)Ca at high energies(>100 MeV),necessitating an exact treatment of double-magic *** results obtained by using the pure microscopic optical potential,WLH,based on the EFT theory show the same trend as those of CTOM but are generally *** JLM potential,which relies on simplified nuclear matter calculations with old-fashioned bare interactions,produces results that are very similar to those of the phenomenological potential *** results indicate that modern

关键词： optical model potentials transfer reactions spectroscopic factors