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nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： M.Hajipour G.R.Ansarifar department of nuclear engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

nuclear power plants exhibit non-linear and time-variable ***,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual *** an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the *** this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled *** an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power *** point kinetics equations with three groups of delayed neutrons were used in the ***-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous *** controlled parameters were reactor power,steam temperature,and ***,for these parameters,the PI controller had certain instabilities in the presence of *** classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering *** was highly accurate and stable and had a small computational *** reality,it followed the desired values without oscillations and chattering.

关键词： Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model

A polarized^(3)He system based on metastability-exchange optical pumping

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Science China(physics,Mechanics & Astronomy) 2024年第7期67卷 72-81页

作者： Yuting Wang Liangyong Wu Kaiyuan Zhang Mei Peng Siyu Chen Haiyang Yan State Key Laboratory of nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of nuclear physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of nuclear physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Key Laboratory of Neutron physics Institute of Nuclear Physics and ChemistryChina Academy of Engineering PhysicsMianyang 621900China

Hyperpolarized^(3)He nuclei have emerged as a significantly important approach in quantum precision measurement techniques,with extensive applications in fundamental physics,magnetometry,metrology,and *** this study,we report on the design and implementation of a^(3)He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastabilityexchange optical pumping(MEOP)*** employed a Merritt coil system consisting of four square coils to furnish a uniform holding *** deployed a 2 W fiber laser to pump the metastable^(3)He atoms and conducted free induction decay(FID)detection of the polarized^(3)He nuclei using both pickup coil and optical *** the optical method,we used a50 m W linearly polarized distributed Bragg reflector(DBR)laser as the *** applied transverse light absorption polarimetry to measure the absolute nuclear polarization of the ground-state^(3)*** have developed cell fabrication capabilities at the CMRR,and cells at various pressures ranging from 100 to 1000 Pa have been fabricated and *** a typical borosilicate cell with 100 Pa pressure,the absolute polarization is measured as Pn≈70%,and the transverse relaxation time is estimated as T2≈0.5 ***,we constructed a few aluminosilicate cells,each carefully filled with pure^(3)He at a pressure of 100 ***,we conducted a comprehensive evaluation of their performance in the context of MEOP.

关键词： metastability exchange optical pumping polarized^(3)He magnetic resonance

Comprehensive analysis of uncertainty quantification for the^(58)Ni(n,p)^(58)Co reaction cross section

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Chinese physics C 2024年第9期48卷 170-175页

作者： Mahesh Choudhary Aman Sharma Namrata Singh Mahima Upadhyay Punit Dubey A.Gandhi Akash Hingu G Mishra Sukanya De L.S.Danu Ajay Kumar R.G.Thomas Saurav Sood Sajin Prasad S.Mukherjee I.N.Ruskov Yu.N.Kopatch A.Kumar department of physics Banaras Hindu UniversityVaranasi 221005India Horia Hulubei National Institute of physics and nuclear engineering-IFIN-HH Bucharest 077125Romania department of physics The Maharaja Sayajirao University of BarodaVadodara 390002India nuclear physics Division Bhabha Atomic Research CentreMumbai 400085India Health physics Division Bhabha Atomic Research CentreMumbai 400085India department of Electrical Power engineering Brno University of TechnologyBrno 61600Czech Republic Institute for nuclear Research and nuclear Energy Bulgarian Academy of SciencesSofia 1784Bulgaria Joint Institute for nuclear Research(JINR) Dubna 141980Russia

In this study,we measured the^(58)Ni(n,p)^(58)Co reaction cross section with neutron energies of 1.06,1.86,and 2.85 *** cross section was measured using neutron activation techniques andγ-ray spectroscopy,and it was compared with cross section data available in the ***,we calculated the covariance matrix of the measured cross section for the aforementioned nuclear *** uncertainties of the theoretical calculation for^(58)Ni(n,p)^(58)Co reaction cross section were calculated via Monte Carlo *** this study,we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross *** theoretical calculations were performed by using *** this study,we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section.

关键词： ^(58)Ni(n p)^(58)Co reaction γ-ray spectroscopy uncertainty quantification of cross section covariance analysis

Deuterium distribution and behavior of blisters in pre-damaged and undamaged tungsten

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Tungsten 2024年第3期6卷 647-656页

作者： Cong Li Xiao-Wa Wang Ran-Ran Su Xuan-Xin Hu Shu-Guang Wei Han-Jun Tu Li-Qun Shi Hong-Liang Zhang Key Laboratory of nuclear physics and Ion-Beam Application Institute of Modern Physics Fudan University School of Mechanical engineering Shanghai Jiao Tong University department of Materials Science and engineering University of Wisconsin

Tungsten(W),as a plasma-facing material,is subjected to high fluence plasma,resulting in both radiation damage and deuterium(D) *** study explores the blistering behavior and D supersaturated layers in both pre-damaged and undamaged W *** achieve a uniform damage profile similar to neutron irradiation,carbon(C) ions with multiple energies and angles were *** samples were further irradiated with low-energy D ions under two fluences at temperatures from ～380 to 640 *** various experimental techniques,we found that pre-damaged W samples can effectively suppress the formation of blistering and lower the threshold temperature at which the surface remains free of *** also observed the prominent D supersaturated peaks within the depth of 20 nm in both pre-damaged and undamaged ***,a close correlation between blistering and the D supersaturation was *** results suggest that neutron irradiation in the fusion reactors could increase the critical D concentration for blistering,while a greater depth of damage facilitated the inward diffusion of D,thereby reducing the D concentration gradient and alleviating surface blistering.

关键词： Tungsten Deuterium Supersaturated layer Blister Ion irradiation Pre-damage

A numerical survey of parameters to reach ignition condition for axial compression of a large-sized field reversed configuration

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Plasma Science and Technology 2024年第5期26卷 47-55页

作者：李宜霖廖晖周海洋孙玄 department of Plasma physics and Fusion engineering School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026People’s Republic of China

Field reversed configuration(FRC)is widely considered as an ideal target plasma for magnetoinertial ***,its confinement and stability,both proportional to the radius,will deteriorate inevitably during radial ***,we propose a new fusion approach based on axial compression of a large-sized *** axial compression can be made by plasma jets or plasmoids converging onto the axial ends of the *** parameter space that can reach the ignition condition while preserving the FRC's overall quality is studied using a numerical model based on different FRC confinement *** is found that ignition is possible for a large FRC that can be achieved with the current FRC formation techniques if compression ratio is greater than 50.A more realistic compression is to combine axial with moderate radial compression,which is also presented and calculated in this work.

关键词： field reversed configuration magnetized target fusion axial compression

Principal components of nuclear mass models

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Science China(physics,Mechanics & Astronomy) 2024年第7期67卷 65-71页

作者： Xin-Hui Wu Pengwei Zhao department of physics Fuzhou UniversityFuzhou 350108China State Key Laboratory of nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871China

Principal component analysis(PCA)is employed to extract the principal components(PCs)present in nuclear mass models for the first *** effects from different nuclear mass models are reintegrated and reorganized in the extracted *** PCs are recombined to build new mass models,which achieve better accuracy than the original theoretical mass *** comparison indicates that using the PCA approach,the effects contained in different mass models can be collaborated to improve nuclear mass predictions.

关键词： nuclear mass principal component analysis nuclear models statistical methods

Model of self-generated magnetic field generation from relativistic laser interaction with solid targets

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Chinese physics B 2024年第5期33卷 511-517页

作者：严睿邹德滨赵娜杨晓虎蒋祥瑞胡理想徐新荣周泓宇余同普卓红斌邵福球银燕 Northwest Institute of nuclear Technology Xi'an 710024China department of physics National University of Defense TechnologyChangsha 410073China School of Microelectronics and physics Hunan University of Technology and BusinessChangsha 410205China department of nuclear Science and Technology National University of Defense TechnologyChangsha 410073China College of engineering physics Shenzhen Technology UniversityShenzhen 518118China

Generation of self-generated annular magnetic fields at the rear side of a solid target driven by relativistic laser pulse is investigated by using theoretical analysis and particle-in-cell *** spatial strength distribution of magnetic fields can be accurately predicted by calculating the net flow caused by the superposition of source flow and return flow of hot *** theoretical model established shows good agreement with the simulation results,indicating that the magnetic-field strength scales positively to the temperature of hot *** provides us a way to improve the magnetic-field generation by using a micro-structured plasma grating in front of the solid *** with that for a common flat target,hot electrons can be effectively heated with the well-designed grating size,leading to a stronger magnetic *** spatial distribution of magnetic fields can be modulated by optimizing the grating period and height as well as the incident angle of the laser pulse.

关键词： self-generated magnetic field laser solid-target interaction micro-structured plasma grating

Unveiling the early universe:Axion-like particles and their role in primordial structure formation

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Science China(physics,Mechanics & Astronomy) 2024年第11期67卷 178-179页

作者： Sergey G.Rubin National Research nuclear University MEPhI(Moscow engineering physics Institute) Moscow 115409Russia

The groundbreaking discovery of gravitational waves(GWs)by the LIGO-VIRGO-KAGRO collaboration has revolutionized our understanding of the universe and opened up a new way of observing cosmic events. Unlike light waves... 详细信息

关键词： universe gravitational cosmic

Footprints of axion-like particle in pulsar timing array data and James Webb Space Telescope observations

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Science China(physics,Mechanics & Astronomy) 2024年第11期67卷 55-62页

作者： Shu-Yuan Guo Maxim Khlopov Xuewen Liu Lei Wu Yongcheng Wu Bin Zhu department of physics Yantai UniversityYantai 264005 China Institute of physics Southern Federal UniversityRostov on Don 344090 Russia National Research nuclear University MEPhI(Moscow engineering physics Institute) Moscow 115409 Russia Virtual Institute of Astroparticle physics Paris 75018 France department of physics and Institute of Theoretical physics Nanjing Normal UniversityNanjing 210023 China

Several pulsar timing array(PTA) collaborations have recently reported the evidence for a stochastic gravitational-wave background(SGWB), which can unveil the formation of primordial seeds of inhomogeneities in the early universe. With the SGWB parameters inferred from PTAs data, we can make a prediction of the seeds for early galaxy formation from the domain walls in the axion-like particles(ALPs) field distribution. This also naturally provides a solution to the observation of high redshifts by the James Webb Space Telescope. The predicted photon coupling of the ALP is within the reach of future experimental searches.

关键词： stochastic gravitational-wave background pulsar timing array axion-like particle JWST

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Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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nuclear Science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan Key Laboratory of nuclear Data China Institute of Atomic EnergyBeijing 102413China School of nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of Fluid physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic *** leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight *** samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 *** leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and *** on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were *** results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data