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Probing dark matter particles from evaporating primordial black holes via electron scattering in the CDEX-10 experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 87-95页

作者： Zhenhua Zhang litao Yang Qian Yue Kejun Kang Yuanjing li Haipeng An Greeshma C. Jianping Chang Yunhua Chen Jianping Cheng Wenhan Dai Zhi Deng Changhao Fang Xinping Geng Hui Gong Qiuju Guo Tao Guo Xuyuan Guo li He Shengming He Jinwei Hu Hanxiong Huang Tuchen Huang lin Jiang S.Karmakar Haubin li Hanyu li Jianmin li Jin li Qianyun li Renmingjie li xueqian li Yulan li Yifan liang Bin liao FongKay lin ShinTed lin Jiaxuan liu Shukui liu Yandong liu Yu liu Yuanyuan liu Hao Ma Yucai Mao Qiyuan Nie Jinhua Ning Hui Pan Ningchun Qi Jie Ren Xichao Ruan Monoj Kumar Singh Tianxi Sun Changjian Tang Yang Tian Guangfu Wang Junzheng Wang li Wang Qing Wang Yufeng Wang Yunxiang Wang Henry Tsz-King Wong Shiyong Wu Yucheng Wu Haoyang Xing Rui Xu Yin Xu Tao Xue Yulu Yan Nan Yi Chunxu Yu Haijun Yu Jianfeng Yue Ming Zeng Zhi Zeng Bingtao Zhang Fengshou Zhang Lei Zhang Zhenyu Zhang Jizhong Zhao Kangkang Zhao Minggang Zhao Jifang Zhou Zuying Zhou Jingjun Zhu CDEX Collaboration Key Laboratory of Particle and Radiation Imaging (Ministry of Education) and Department of Engineering Physics Tsinghua University Department of Physics Tsinghua University Institute of Physics Academia Sinica NUCTECH Company YaLong River Hydropower Development Company College of Nuclear Science and Technology Beijing Normal University College of Physics Sichuan University School of Physics Peking University Department of Nuclear Physics China Institute of Atomic Energy Sino-French Institute of Nuclear and Technology Sun Yet-sen University School of Physics Nankai University Department of Physics Banaras Hindu University Department of Physics Beijing Normal University

Dark matter（DM） is a major constituent of the ***,no definite evidence of DM particles（denoted as “χ”） has been found in DM direct detection（DD） experiments to *** is a novel concept of detectingχfrom evaporating primordial black holes（PBHs）.We search forχemitted from PBHs by investigating their interaction with target *** examined PBH masses range from 1×1015to 7×1016g under the current limits of PBH abundance *** 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude the χ-electron（χ-e） elastic-scattering cross section σχe～5×10-29cm2for χ with a mass ■ keV from our *** the higher radiation background but lower energy threshold（160 eV）,CDEX-10 fills a part of the gap in the previous *** (mχ,σχe) can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.

关键词： CDEX primordial black hole light dark matter particle dark matter-electron scattering high purity germanium detector

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Increase of the K^(+)/π^(+) Ratio Induced by Collective Effects in Relativistic Heavy-Ion Collisions

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Chinese Physics Letters 1994年第8期11卷 476-479页

作者： ZHENG Shian li xueqian Chinese Centre of Advanced Science and Technology(World Laboratory) P.O.Box 8730Beijing 100080 Department of Physics Nankai UniversityTianjin 300071

The collective effects on the increase of the K^(+)/π^(+) ratio in relativistic heavy-ion collisions are analyzed with the excited nucleon *** gradual increase of the K^(+)/π^(+) ratio from p-Be to p-Au to the Si-Au central collisions may be explained self-consistently by multiscattering and secondary hadron collisions without requiring the formation of the4quark gluon plasma.

关键词： collective excited quark

Synergy between thermal and nonthermal effects in plasmonic photocatalysis

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Nano Research 2020年第5期13卷 1268-1280页

作者： xueqian li Henry O.Everitt Jie liu Department of Chemistry Duke UniversityDurhamNC 27708USA 2 U.S.Army Combat Capabilities Development CommandAviation&Missile CenterRedstone ArsenalAL 35898USA Department of Physics Duke UniversityDurhamNC 27708USA Present address:Department of Applied Physics and Materials Science California Institute of TechnologyPasadenaCA 91125USA

Plasmonic photocatalysis represents the synergetic union of two active fields of research:plasmonic effects in illuminated metallic nanoparticles and catalytic effects in tailored metallic ***,metallic nanoparticles that excel for one application are limited for the other,but recent developments have shown that desirable catalytic behaviors,such as reduced activation barriers and improved product selectivity,derive from nonthermal behaviors uniquely produced by this *** examining such findings,this review will address a specific debate that has recently surfaced:what is the relative degree of contributions of thermal and nonthermal effects in plasmonic photocatalysis?We demonstrate the importance of correctly accounting for thermal effects before characterizing nonthermal *** show that another synergy occurs:these desirable nonthermal behaviors have a temperature dependence,and the resulting temperature-dependent reaction rates far exceed what can be explained from purely thermal effects ***,the synergy of plasmonic photocatalysis offers an exciting new contribution to the quest for efficient,selective,sustainable methods for chemical synthesis and energy conversion.

关键词： plasmonic catalysis hot carriers photothermal catalysis localized surface plasmon

Confirming nonthermal plasmonic effects enhance CO2 methanation on Rh/TiO2 catalysts

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Nano Research 2019年第8期12卷 1906-1911页

作者： xueqian li Henry O. Everitt Jie liu Department of Chemistry Duke UniversityDurhamNC 27708USA Army Combat Capabilities Development Command Aviation & Missile CenterRedstone ArsenalAL 35898USA Department of Physics Duke UniversityDurhamNC 27708USA

In some cases, illumination of traditional thermal catalysts and tailored plasmonic photocatalysts may synergistically combine thermal and nonthermal mechanisms to enhance reaction rates and improve product selectivity at reduced temperatures. To understand how these attributes are achieved in plasmon-driven catalysis, these intertwined thermal and nonthermal effects must be untangled. Here, we show how a novel indirect illumination technique, in conjunction with precisely monitored thermal profiles of the catalyst, can confirm and clarify the role of nonthermal effects in plasmon-enhanced carbon dioxide methanation on a Rh/TiO2 photocatalyst. We find that the extracted nonthermal methane production rate has a linear dependence on the top surface temperature, distinctly different from an exponential dependence for thermal catalysis. We also find that the apparent quantum efficiency from the nonthermal contribution has no dependence on light intensity but maintains a linear dependence on top surface temperatures between 200 and 350℃. The clear exposition of nonthermal effects in the Rh/TiO2 plasmonic photocatalyst illustrates how this methodology may be applied for the quantitative evaluation of thermal and nonthermal light effects in other plasmon-enhanced catalytic reactions.

关键词： carbon dioxide reduction plasmonic photocatalysis hot carriers photothermal heating rhodium nanoparticles

外商直接投资视角下数字经济对绿色创新效率的影响

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运筹与模糊学 2024年第2期14卷 780-788页

作者：周欣雨秦炳涛李学迁上海理工大学管理学院上海

“绿色化”“贸易出口”和“数字化”是中国未来经济发展的重要方向。厘清外商直接投资、数字经济与绿色创新效率的关系将有利于我国实现建设生态文明的千年大计。基于2013~2023年我国省级层面面板数据,在此基础之上构建面板回归模型,... 详细信息

“绿色化”“贸易出口”和“数字化”是中国未来经济发展的重要方向。厘清外商直接投资、数字经济与绿色创新效率的关系将有利于我国实现建设生态文明的千年大计。基于2013~2023年我国省级层面面板数据,在此基础之上构建面板回归模型,深层次了解外商直接投资视角之下,数字经济对绿色创新效率发展的作用。研究结果表明:我国绿色创新效率取得了明显的提升,但是整体发展还不够成熟呈现出阶梯式的发展趋势;外商直接投资能正向调节数字经济对绿色创新效率的促进作用。为此,本文从建议制定科学合理的外资引进政策、制定合理的绿色创新政策等角度提出对策建议。

关键词：数字经济绿色创新效率外商直接投资

血清血管内皮生长因子及趋化因子CXC配体12对2型糖尿病并发微血管病变的预测价值

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陕西医学杂志 2024年第3期53卷 331-334,339页

作者：李雪倩禚映辰李婷陈珂西安交通大学第二附属医院陕西西安710004 西安交通大学第一附属医院陕西西安710061 商洛市中心医院陕西商洛726000

目的:探究血清血管内皮生长因子(VEGF)及趋化因子CXC配体12(CXCL12)对2型糖尿病(T2DM)并发微血管病变的预测价值。方法:选取单纯T2DM患者90例为单纯T2DM组(A组),选取T2DM并发微血管病变患者90例为T2DM并发微血管病变(B组),同时体检健康... 详细信息

目的:探究血清血管内皮生长因子(VEGF)及趋化因子CXC配体12(CXCL12)对2型糖尿病(T2DM)并发微血管病变的预测价值。方法:选取单纯T2DM患者90例为单纯T2DM组(A组),选取T2DM并发微血管病变患者90例为T2DM并发微血管病变(B组),同时体检健康者90例为对照组(C组)。比较三组血压、糖脂及肾功能指标水平,以及血清VEGF、CXCL12水平。分析T2DM并发微血管病变的危险因素。分析血清VEGF、CXCL12对T2DM并发微血管病变的预测价值。结果:与C组比较,A组和B组患者收缩压(SBP)、舒张压(DBP)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、空腹血糖(FBG)、血肌酐(Scr)、血尿素氮(BUN)、VEGF和CXCL12水平升高(均P<0.05)。与A组比较,B组上述指标水平升高(均P<0.05)。Logistic回归分析结果显示,TC、FBG、Scr、VEGF、CXCL12是T2DM并发微血管病变的独立危险因素(均P<0.05)。相关性分析表明,VEGF、CXCL12与TC、FBG、Scr呈正相关(均P<0.05)。受试者工作特征(ROC)曲线分析显示,VEGF、CXCL12对T2DM并发微血管病变均有一定的预测价值,两者联合的预测价值更高(均P<0.05)。结论:血清VEGF、CXCL12在单纯T2DM和T2DM并发微血管病变患者中水平均升高,且T2DM并发微血管病变患者中水平更高。两者对T2DM并发微血管病变有一定预测价值,且两者联合价值更高。

关键词： 2型糖尿病微血管病变血管内皮生长因子 CXC配体12 预测价值

ESG表现对中国制造业企业国际竞争力的影响研究

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运筹与模糊学 2024年第2期14卷 29-40页

作者：秦炳涛原瑞霞李学迁上海理工大学管理学院上海

随着全球市场的日益竞争和社会对可持续发展的日益关注,环境、社会和公司治理绩效(ESG)因其综合性和可持续性而成为制造业企业保持竞争力的关键要素之一。本文选取2016~2021年沪深A股制造业上市公司数据作为研究样本,基于固定效应模型,... 详细信息

随着全球市场的日益竞争和社会对可持续发展的日益关注,环境、社会和公司治理绩效(ESG)因其综合性和可持续性而成为制造业企业保持竞争力的关键要素之一。本文选取2016~2021年沪深A股制造业上市公司数据作为研究样本,基于固定效应模型,实证检验ESG表现对中国制造业企业国际竞争力的影响。研究表明:ESG表现能显著提高制造业企业国际竞争力。此外,根据行业和产权性质划分的分组研究表明:非重污染企业和非国有企业更容易通过ESG表现提高其国际竞争力。进一步分析发现,重污染企业滞后一期后的ESG表现能显著提升其国际竞争力,即从长期来看,重污染企业积极的ESG表现可以提升其国际竞争力。研究结论不仅为我国ESG政策优化和实施提供了理论和实证参考,而且对我国企业提升国际竞争力、践行可持续发展理念具有重要启示。

关键词： ESG表现企业国际竞争力行业性质产权性质

Z′particles and e^+ e^- → τ^+ μ^-

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Science China(Physics,Mechanics & Astronomy) 2010年第11期53卷 1988-1991页

作者： TieJun Gao TaiFu Feng xueqian li ZongGuo Si ShuMin Zhao Department of Physics Dalian University of Technology Department of Physics Nankai University

We analyze the cross section of e + e-→τ + μ-within the frameworks of SM and its Z *** theoretical prediction of the SM on the total cross section is suppressed by the tiny neutrino *** the other hand,the contributions from Z to the cross section are enhanced drastically because of the tree level FCNC couplings among Z and leptons.

关键词： Z′model FCNC

配戴离焦设计框架镜与角膜塑形镜对儿童近视眼控制效果的比较

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中华眼外伤职业眼病杂志 2024年第2期46卷 87-93页

作者：李雪倩王珍张利红陈秋菊郑州市中医院眼科郑州450006

目的比较7~14岁低度及中度近视儿童配戴离焦设计框架镜(PMDSL)与角膜塑形镜(OK镜)对近视控制的临床效果。方法前瞻性非随机对照研究。纳入2021年6月至2022年6月在郑州市中医院验配PMDSL(39例)和OK镜(42例)的7~14岁儿童,近视度数为-6.00~... 详细信息

目的比较7~14岁低度及中度近视儿童配戴离焦设计框架镜(PMDSL)与角膜塑形镜(OK镜)对近视控制的临床效果。方法前瞻性非随机对照研究。纳入2021年6月至2022年6月在郑州市中医院验配PMDSL(39例)和OK镜(42例)的7~14岁儿童,近视度数为-6.00~-0.75 D。所有纳入者只取右眼数据进行统计分析。根据近视儿童的矫正方式及散瞳后屈光度[以等效球镜度(SE)表示]分为四组:低度近视PMDSL组21例(-3.00 D≤SE<-0.50 D)、低度近视OK镜组23例(-3.00 D≤SE<-0.50 D)、中度近视PMDSL组18例(-6.00 D≤SE<-3.00 D)以及中度近视OK镜组19例(-6.00 D≤SE<-3.00 D);观察比较四组儿童戴镜前及戴镜后半年及1年的屈光度及眼轴长度(AL)的数据。结果低中度近视PMDSL组及OK镜组戴镜后的AL和SE均呈上升趋势,戴镜前的AL及SE与戴镜后各时间段相比较差异均有统计学意义(均P<0.05)。低度近视PMDSL组和OK镜组两组1年的SE变化量分别为-0.25(-0.50,0.00)D和-0.25(-0.25,-0.25)D,AL的变化量分别为0.11(0.06,0.31)mm和0.26(0.12,0.41)mm,两者对比差异无统计学意义(SE:Z=-1.73,P=0.083;AL:Z=1.61,P=0.107);中度近视PMDSL组和OK镜组两组1年的SE变化量分别为-0.50(-0.56,-0.25)D和0.00(-0.25,0.00)D,AL的变化量分别为0.35(0.17,0.42)mm和0.13(0.08,0.31)mm;两组对比差异有统计学意义(SE:Z=-3.79,P<0.001;AL:Z=2.67,P=0.007)。结论配戴PMDSL与OK镜均能有效地矫正儿童近视眼,OK镜对中度近视的进展控制效果更好。

关键词：近视接触镜角膜塑形术离焦设计框架镜等效球镜度眼轴长度儿童