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Nuclear Science and Techniques 2023年第1期34卷 23-32页

作者： Da‑Jun Zhao Song Feng Pin‑Jing Cheng Rong Liu Wen Luo Hao‑Qiang Wang jie‑ming xue Kun Zhu Bo Zheng School of Nuclear Science and Technology University of South ChinaHengyang 421001China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

To reduce the experimental uncertainty in the 235 U resonance energy region and improve the detection efficiency for neutron total cross section measurements compared with those obtained with the neutron total cross section spectrometer(NTOX), a dedicated lithium-containing scintillation detector has been developed on the Back-n beam line at the China Spallation Neutron Source. The Fast Scintillator-based Neutron Total Cross Section(FAST) spectrometer has been designed based on a Cs2Li La Br6(CLLB) scintillator considering the γ-ray flash and neutron environment on the Back-n beam line. The response of the CLLB scintillator to neutrons and γ-rays was evaluated with different 6Li/7 Li abundance ratios using Geant4. The neutron-γdiscrimination performance of the CLLB has been simulated considering different scintillation parameters, physical designs,and light readout modes. A cubic 6Li-enriched( > 90%) CLLB scintillator, which has a thickness of 4-9 mm and side length of no less than 50 mm to cover the Φ 50 mm neutron beam at the spectrometer position, has been proposed coupling to a side readout SiPM array to construct the FAST spectrometer. The developed simulation techniques for neutron-γ discrimination performance could provide technical support for other neutron-induced reaction measurements on the Back-n beam line.

关键词： Neutron total cross section CLLB scintillator Geant4 Pulse shape discrimination(PSD)

Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3 eV to 20 MeV on the Back-n at CSNS

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Nuclear Science and Techniques 2024年第2期35卷 85-93页

作者： jie-ming xue Song Feng Yong-Hao Chen Han Yi Min Xiao Pin-Jing Cheng Xin-Xiang Li Rong Liu Yi-Wei Yang Zi-jie Han Da-Jun Zhao Hao-Qiang Wang Bao-Qian Li Ji-Rong Zhao Lei-Xun Tang Wen Luo Bo Zheng School of Nuclear Science and Technology University of South ChinaHengyang 421001China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron *** energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick high-purity natural lead sample was employed for the neutron transmission *** on-beam background was determined using Co,In,Ag,and Cd *** excitation function of ^(nat)Pb(n,tot)reaction below 20 MeV was calculated using the TALYS-1.96 nuclear-reaction modeling *** present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3,JENDL-5,CENDL-3.2,and BROND-3.1),and the theoretical calculation *** agreement was found between the new results and those of previous experiments and with the theoretical curves in the corresponding *** measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy *** provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead.

关键词： Neutron-induced total cross section Natural lead Time-of-flight TALYS-1.96 CSNS Back-n white neutron beamline

Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU Lin LI xue XIE Jun DONG ming School of Energy and Power Engineering Dalian University of Technology School of Optical Information and Energy Engineering Wuhan Institute of Technology School of Energy and Environment Shenyang Aerospace University

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method（LES-DEM） *** validity of the LES approach was verified by comparison with available direct numerical simulation（DNS） *** adopted the Johnson-Kendall-Roberts（JKR） contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters（dp=2-20 μm） in the laminar and transition of shear layer（TrSL） flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise（y-direction）.With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： discrete element method large eddy simulation microparticle particle agglomeration

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一种基于簇链式的异构WSN路由协议

贵州师范学院学报 2016年第9期32卷 1-6页

作者：汪杰汪学明贵州大学大数据与信息工程学院贵州贵阳550025 贵州大学计算机科学与技术学院贵州贵阳550025

为了降低异构无线传感器网络的能耗,提高网络吞吐量。综合Chain-Based协议和SEP协议的优点,在给定一种新的异构网络环境下,提出了一种基于簇链式的异构WSN路由协议。首先基站依据地理位置将监测区域划分成簇,然后簇内节点按照最近距离... 详细信息

为了降低异构无线传感器网络的能耗,提高网络吞吐量。综合Chain-Based协议和SEP协议的优点,在给定一种新的异构网络环境下,提出了一种基于簇链式的异构WSN路由协议。首先基站依据地理位置将监测区域划分成簇,然后簇内节点按照最近距离成链。在簇头的选取阶段,以节点的剩余能量与所在区域的平均能量选取候选簇头,接着按照给定的阈值选取最终簇头节点和Leader节点。对比仿真结果表明,该协议对网络能耗、吞吐量和生命周期的优化都优于Chain-Based协议和SEP协议。

关键词：异构无线传感器簇链式能耗生命周期吞吐量

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期7卷 32-49页

作者： Li-Rong Xiao Chen Chen Shuo Wang Zi-Yin Dai Hideo Kimura Cui Ni Chuan-Xin Hou xue-Qin Sun Si-jie Guo Wei Du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with Ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys Solid hydrogen storage Transition metal elements

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen xue-Jun Li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

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Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： Jian Li Wen Yi XiangHui xue jie Zeng HaiLun Ye JianYuan Wang JinSong Chen Na Li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy

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Computers, Materials & Continua 2025年第1期82卷 997-1026页

作者： Li Ma Cai Dai Xingsi xue Cheng Peng School of Computer Science Shaanxi Normal UniversityXi’an710119China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou350118China Information Construction and Management Center and Institute of Artificial Intelligence and Educational New Productivity Ningxia Normal UniversityGuyuan756099China

The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization *** the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search ***,two update strategies based on decomposition are used to update the evolving population and external archive,***,a multiselection strategy is *** first strategy is for the subspace without a non-dominated *** the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global *** second strategy is for the subspace with a non-dominated *** the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local *** third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated *** the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to ***,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search ***,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test *** results show that the proposed algorithm has better performance.

关键词： Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy

The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi Li Jing xue Yuejia Ma Ke Ye xue Zhao Fangliang Ge Feifei Zheng Lulu Liu Xu Gao Dayong Wang Qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

四联疗法联合口腔洁治对胃溃疡患者胃幽门螺杆菌根除的临床疗效观察

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中国实用医药 2018年第9期13卷 100-102页

作者：蔡明杰宋学琴山东省诸城市相州中心卫生院 262202 山东省诸城市中心卫生院

目的探究四联疗法联合口腔洁治对胃溃疡患者胃幽门螺杆菌(Hp)根除的临床治疗效果,为临床医学提供治疗经验。方法 120例经14碳呼气试验(^(14)C-UBT)确诊胃Hp感染阳性且Hp唾液测试板(Hp S)确诊口腔Hp感染阳性的胃溃疡患者,以随机分组方式... 详细信息

目的探究四联疗法联合口腔洁治对胃溃疡患者胃幽门螺杆菌(Hp)根除的临床治疗效果,为临床医学提供治疗经验。方法 120例经14碳呼气试验(^(14)C-UBT)确诊胃Hp感染阳性且Hp唾液测试板(Hp S)确诊口腔Hp感染阳性的胃溃疡患者,以随机分组方式分为观察组和对照组,每组60例。观察组患者给予10 d四联疗法和口腔清洁疗法进行干预,对照组患者仅给予10 d四联疗法,并不进行口腔清洁护理。比较两组治疗结束后1个月的胃Hp根除、口腔Hp阳性情况,以及治疗结束后3个月的胃Hp复发、口腔Hp阳性情况。结果治疗结束后1个月,观察组患者胃Hp根除率及口腔Hp阳性率分别为90.0%、21.7%,均明显优于对照组的70.0%、65.0%,差异具有统计学意义(P<0.05)。治疗结束后3个月,观察组患者胃Hp复发率及口腔Hp阳性率分别为13.3%、20.0%,均明显低于对照组的41.7%、61.7%,差异具有统计学意义(P<0.05)。结论采用四联疗法联合口腔洁治对胃溃疡患者进行干预,能够有效保证患者的胃Hp指数维持正常,使患者口腔Hp指数维持正常。口腔Hp可能是导致胃溃疡疾病复发的原因。

关键词：四联疗法口腔洁治胃溃疡幽门螺杆菌根除