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

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

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城镇住宅家庭用能画像构建——以京津冀地区为例

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清华大学学报（自然科学版） 2024年第8期64卷 1482-1491页

作者：刘心男宋来昊纪颖波北方工业大学土木工程学院北京100144

为精准引导城镇住宅家庭节能,该文基于用户画像理论从多维度视角构建了城镇住宅家庭用能画像模型。以京津冀地区城镇住宅家庭为研究对象,基于文献研究从家庭属性、建筑特征、家电设备、用能行为、能源消耗以及可再生能源使用6个维度构... 详细信息

为精准引导城镇住宅家庭节能,该文基于用户画像理论从多维度视角构建了城镇住宅家庭用能画像模型。以京津冀地区城镇住宅家庭为研究对象,基于文献研究从家庭属性、建筑特征、家电设备、用能行为、能源消耗以及可再生能源使用6个维度构建了家庭用能画像标签体系,采用调查问卷及半结构化访谈方法获取351份家庭用能数据。基于标签平均轮廓系数,采用向后特征选择法确定画像标签最优子集,采用k-means算法对城镇住宅家庭聚类分析。结果表明:城镇住宅家庭用能画像标签最优子集包括家庭人口、建筑面积、房屋使用方式、家电设备数量、空调行为、年用电量、年用气量和太阳能设备8个标签;可将京津冀地区城镇住宅家庭划分为用能品质型、节能潜力型、用能规律型和节能环保型4类。该研究结果可为制定家庭节能精准引导策略提供理论参考。

关键词：城镇住宅家庭家庭用能画像 k-means聚类特征选择

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不同纤维增强对PZT/PVA复合材料性能影响的研究

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塑料工业 2024年第1期52卷 114-122,128页

作者：姬程飞宋崇阳黄河交通学院交通工程学院河南焦作454950 西安建筑科技大学土木工程学院陕西西安710055

压电陶瓷复合材料较低的力学性能限制其应用。为进一度探究纤维种类及掺量对锆钛酸铅(PZT)/聚乙烯醇(PVA)复合材料性能影响规律,对不同纤维掺量下碳纤维/PZT/PVA、芳纶纤维/PZT/PVA复合材料开展电学及力学性能测试,分析纤维种类、掺量及... 详细信息

压电陶瓷复合材料较低的力学性能限制其应用。为进一度探究纤维种类及掺量对锆钛酸铅(PZT)/聚乙烯醇(PVA)复合材料性能影响规律,对不同纤维掺量下碳纤维/PZT/PVA、芳纶纤维/PZT/PVA复合材料开展电学及力学性能测试,分析纤维种类、掺量及PZT/PVA体积比对试件介电、压电性能及弯曲、拉伸性能的影响规律,并结合电镜扫描(SEM)分析纤维掺量对试件性能的影响。结果表明,少量的纤维掺量能够提高复合材料的电学性能,过量的纤维使得复合材料结构孔隙结构增加,介质常数和压电常数均减小,介质损耗增大。7%芳纶纤维/0.5PZT/0.5PVA、5%芳纶纤维/0.6PZT/0.4PVA、3%芳纶纤维/0.7PZT/0.3PVA复合材料的介电性能和压电性能较高。芳纶纤维掺量为9%时,芳纶纤维/0.5PZT/0.5PVA、芳纶纤维/0.6PZT/0.4PVA、芳纶纤维/0.7PZT/0.3PVA、芳纶纤维/0.8PZT/0.2PVA复合材料的弯曲强度分别提高了10.72%、14.49%、13.85%及16.78%,拉伸强度分别提高了24.04%、23.94%、27.00%和28.52%。纤维在试件内部形成网状结构从而提升试件力学性能,且由于芳纶纤维不导电,因此可以在复合材料中加入芳纶纤维的数量比碳纤维多,其力学性能也会大大提高。

关键词：碳纤维芳纶纤维锆钛酸铅/聚乙烯醇介电性能压电性能力学性能微观结构

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异质性债务融资与企业全要素生产率——基于创新投资与政府补贴视角的观察

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商业研究 2024年第4期 117-129页

作者：姬新龙宋亚枫兰州财经大学金融学院兰州730020

企业全要素生产率(TFP)的提升对企业转型升级与经济可持续发展至关重要。本文选取2018—2022年A股上市企业面板数据,基于异质债务假说,对债务融资影响企业全要素生产率进行全面分析,同时观察创新投资和政府补贴在其中的中介和调节效应... 详细信息

企业全要素生产率(TFP)的提升对企业转型升级与经济可持续发展至关重要。本文选取2018—2022年A股上市企业面板数据,基于异质债务假说,对债务融资影响企业全要素生产率进行全面分析,同时观察创新投资和政府补贴在其中的中介和调节效应。研究发现:债务融资正向影响企业全要素生产率,其中关系型债务起到显著促进作用,而交易型债务则表现出抑制影响;创新投资在债务融资对企业全要素生产率的传导路径中具有显著的中介效应;政府补贴对创新投资与企业全要素生产率之间的关系具有倒“U型”调节效应,而且当政府补贴强度高于一定值时,该正向调节效应会被削弱。新时代推进企业全要素生产率提升,加快企业转型升级,需努力拓宽企业债务融资渠道,尤其要发挥好政府的主导作用。

关键词：异质性债务融资创新投资全要素生产率政府补贴

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Layered kagome compound Na_(2)Ni_(3)S_(4)with topological flat band

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Chinese Physics B 2024年第5期33卷 153-159页

作者：叶君耀林益浩王浩哲宋志达冯济谢韦伟贾爽 International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Department of Chemistry Michigan State UniversityMI48824USA Hefei National Laboratory Hefei 230088China Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials Peking UniversityBeijing 100871China

We report structural and electronic properties of Na_(2)Ni_(3)S_(4),a quasi-two-dimensional compound composed of alternating layers of[Ni_(3)S_(4)]^(2-)and Na^(+).The compound features a remarkable Ni-based kagome lattice with a square planar configuration of four surrounding S atoms for each Ni *** and electrical measurements reveal a weak paramagnetic insulator with a gap of about 0.5 *** band structure calculation highlights a set of topological flat bands of the kagome lattice derived from the rotated dxz-orbital with C_(3)+T symmetry in the presence of crystal-field splitting.

关键词： kagome lattice flat band

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Enhanced back-illuminated GaO-based solar-blind ultraviolet photodetectors

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Science China Technological Sciences 2024年

作者： YAN ZuYong ZHI Yu song ji XueQiang YUE jianYing WANG jinjin LIU Zeng LI Shan LI PeiGang HOU ShangLin WU Gang LEI jingLi TANG WeiHua School of Science State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology China Academy of Launch Vehicle Technology School of Integrated Circuits & State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications School of Electronic Information Engineering Inner Mongolia University College of Electronic and Optical Engineering & College of Microelectronics National and Local Joint Engineering Laboratory for RF Integration and Micro-Packing Technologies Nanjing University of Posts and Telecommunications

Ga2O3is a promising material for deep-ultraviolet （DUV） photodetectors due to its ultra-wide bandgap and high thermal and chemical ***,because of their relatively low responsivity,Ga2O3-based photodetectors still have difficulty meeting the requirements of practical ***,we construct a high-performance Ga2O3photodetector realized by *** high-crystallinity epitaxially grown Ga2O3as the DUV absorbing layer and the double-polished Al2O3substrate as the transparent window for injection of photons,the device operating in the back-illuminated mode exhibits a higher DUV photoresponse and faster response speed than in the front-illuminated ***,our experimental results have led to the development of a novel strategy for designing and fabricating high-performance Ga2O3photodetectors.

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Prevalence of nicotine dependence among smokers aged 40 years and older in China

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Chinese Medical Journal Pulmonary and Critical Care Medicine 2024年第2期2卷 119-131页

作者： Ying ji Shu Cong jing Fan Ning Wang Wenjing Wang Xuping song Liwen Fang Chinese Field Epidemiology Training Program Chinese Center for Disease Control and Prevention27 Nanwei RoadXicheng DistrictBeijing 100050China National Center for Chronic and Non-communicable Disease Control and Prevention Chinese Center for Disease Control and Prevention27 Nanwei RoadXicheng DistrictBeijing 100050China Zunyi Center for Disease Control and Prevention ZunyiGuizhou 563000China

Background:Nicotine dependence,also known as tobacco dependence,is a common chronic disease and a major risk factor for chronic respiratory *** present study was designed to determine the prevalence of nicotine dependence and its changes among smokers aged 40 years and older in China,to analyze the characteristics of nicotine dependence among smokers,and to provide a reference for smoking cessation ***:The data were sourced from nationally representative large-sample surveys conducted during 2014-2015 and 2019-2020 in the Chinese population,covering 125 counties(districts)in 31 provinces,autonomous regions and *** related to smoking and nicotine dependence among residents≥40 years old were collected in face-to-face interviews.A total of 20,062 and 18,975 daily smokers were included in the 2014-2015 and 2019-2020 surveys,*** severity of nicotine dependence was evaluated according to the Fagerström Test for Nicotine Dependence and Heaviness of Smoking *** level and change in nicotine dependence among daily smokers aged≥40 years were estimated using a complex weighted sampling design,and their influencing factors were ***:Levels of nicotine dependence among daily smokers aged≥40 years in China could be divided into very low,low,medium,high,and very high,accounting for 31.1%,27.9%,13.4%,20.5%,and 7.1%of the total,*** average Fagerström Test for Nicotine Dependence score was 3.9(95%confidence interval[CI]:3.8-4.0),with the prevalence of medium-high nicotine dependence being 41.0%(95%CI:39.0-42.9%)and that of high and very high nicotine dependence being 27.6%(95%CI:26.0-29.3%),both of which were significantly higher in men than in women(both P<0.001).Among daily smokers,those with a low education level,age at smoking initiation<18 years,and with smoking duration of≥20 years had a higher degree of nicotine *** terms of geographic region,the level of medium-high nicotine d

关键词： Nicotine dependence Chronic obstructive pulmonary disease Surveillance Smoking cessation Tobacco control Distribution

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Catalpa bignonioides extract improves exercise performance through regulation of growth and metabolism in skeletal muscles

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Asian Pacific Journal of Tropical Biomedicine 2024年第2期14卷 47-54页

作者： Hoibin Jeong Dong-joo Lee Sung-Pil Kwon SeonJu Park song-Rae Kim Seung Hyun Kim Jae-Il Park Deug-chan Lee Kyung-Min Choi WonWoo Lee ji-Won Park Bohyun Yun Su-Hyeon Cho Kil-Nam Kim Seoul Center Korea Basic Science InstituteSeoul 02841Republic of Korea Chuncheon Center Korea Basic Science InstituteChuncheon 24341Republic of Korea Research&Development Center Chungdam CDC JNPharm LLC.Chuncheon 24341Republic of Korea Department of Biomedical Technology Kangwon National UniversityChuncheon 24341Republic of Korea Yonsei Institute of Pharmaceutical Sciences College of PharmacyYonsei UniversityIncheon 21983Republic of Korea Gwangju Center Korea Basic Science InstituteGwangju 61751Republic of Korea Honam National Institute of Biological Resources 99Gohadoan-gilMokpo-siJeollanam-do58762Republic of Korea Department of Bio-analysis Science University of Science&TechnologyDaejeon34113Republic of Korea

Objective:To evaluate the effects of Catalpa bignonioides fruit extract on the promotion of muscle growth and muscular capacity in vitro and in ***:Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide *** proliferation was assessed using a 5-bromo-2’-deoxyuridine(BrdU)assay *** blot analysis was performed to determine the protein expressions of related *** effects of Catalpa bignonioides extract were investigated in mice using the treadmill exhaustion test and whole-limb grip strength *** composition analysis was performed using high-performance liquid chromatography(HPLC).Results:Catalpa bignonioides extract increased the proliferation of C2C12 mouse myoblasts by activating the Akt/mTOR signaling *** also induced metabolic changes,increasing the number of mitochondria and glucose metabolism by phosphorylating adenosine monophosphate-activated protein *** an in vivo study,the extract-treated mice showed improved motor abilities,such as muscular endurance and grip ***,HPLC analysis showed that vanillic acid may be the main component of the Catalpa bignonioides extract that enhanced muscle ***:Catalpa bignonioides improves exercise performance through regulation of growth and metabolism in skeletal muscles,suggesting its potential as an effective natural agent for improving muscular strength.

关键词： Catalpa bignonioides Skeletal muscle Cell proliferation Mitochondria Energy metabolism C2C12

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重庆官栈河大桥主桥主墩基础锁口钢管桩围堰加固

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桥梁建设 2024年第1期54卷 148-154页

作者：钱骥荚瑞馨宋世杰杨纪鹏重庆交通大学土木工程学院重庆400074 重庆交通大学山区桥梁与隧道工程国家重点实验室重庆400074

重庆官栈河大桥主桥为(62+110+62)m三跨连续刚构桥,主墩基础采用锁口钢管桩围堰施工。围堰施工正常水位+325.300 m,施工期控制水位+330.500 m。在该桥主墩围堰完成四周锁口钢管桩插打及前4道内支撑安装后,因极端天气原因,长寿湖水位上涨... 详细信息

重庆官栈河大桥主桥为(62+110+62)m三跨连续刚构桥,主墩基础采用锁口钢管桩围堰施工。围堰施工正常水位+325.300 m,施工期控制水位+330.500 m。在该桥主墩围堰完成四周锁口钢管桩插打及前4道内支撑安装后,因极端天气原因,长寿湖水位上涨到+332.200 m,危及围堰安全。为解决钢管桩围堰的安全问题,提出采用水下施工内支撑的加固方案。待围堰内部水头与外部保持一致后,将已经插打的锁口钢管桩加高至标高+334.000 m,拆除已安装好的4道内支撑,重新安装6道内支撑。采用MIDAS Civil软件分别建立加固前、后钢管桩围堰结构有限元模型,分析钢管桩及内支撑的受力安全与稳定性。结果表明:施工控制水位+330.500 m下,围堰结构最大正应力由加固前的162.6 MPa下降到加固后的82.3 MPa,下降了49.3%;承载水位可从施工控制水位+330.500 m增加到目标控制水位+333.500 m,且强度和刚度等均留有一定储备。水下施工内支撑的加固方案可提升围堰的承载能力。该桥围堰加固后整体受力效果良好,已顺利完成承台浇筑施工。

关键词：刚构桥锁口钢管桩围堰加固有限元法桥梁施工

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“一带一路”贸易便利化的十年进展、问题分析与推进路径

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西北大学学报（哲学社会科学版） 2024年第2期54卷 54-64页

作者：王颂吉韩瑞西北大学经济管理学院陕西西安710127

共建“一带一路”走过了蓬勃十年,它不仅是中国新时代扩大对外开放的总抓手,而且为国际社会提供了重要合作平台。贸易畅通是共建“一带一路”的核心任务之一,贸易便利化对推动“一带一路”贸易畅通至关重要。在共建“一带一路”十周年之... 详细信息

共建“一带一路”走过了蓬勃十年,它不仅是中国新时代扩大对外开放的总抓手,而且为国际社会提供了重要合作平台。贸易畅通是共建“一带一路”的核心任务之一,贸易便利化对推动“一带一路”贸易畅通至关重要。在共建“一带一路”十周年之际,本文从商签自贸协定、加强海关合作、交通互联互通、发展贸易新业态四个方面,系统总结十年来“一带一路”贸易便利化的历程与进展,剖析当前存在的问题,探讨进一步提升贸易便利化水平的路径。

关键词： “一带一路”倡议贸易便利化贸易畅通新型全球化自由贸易协定服务贸易跨境电商

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