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Cretaceous Meteorite Impact-Induced Initial subduction:Records of highly Siderophile Element Abundances and Re-Os Isotopes in Ophiolites

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Journal of Earth Science 2022年第6期33卷 1526-1534页

作者： Benxun su Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China

Compiled global ophiolite data reveal that Cretaceous ophiolites exhibit broaden variations in 187Re/188Os and ^(187)Os/^(188)Os values,increases in Re concentrations and thus Re/Os ratios in all peridotites and chromitites,and additional increased PPGE/IPGE(Pd-subgroup platinum-group element(PGE)/Ir-subgroup PGE)ratios in chromitites and dunites relative to pre-Cretaceous *** compositional changes in Cretaceous ophiolites,which mostly formed in subduction initiation settings,cannot be attributed solely to involvement of subducting or previously subducted crustal ***,the author proposes a Cretaceous meteorite impact model that led to impact-induced disruption of oceanic lithosphere,asthenosphere upwelling,subduction initiation at edges of laterally spreading ***-pressure and high-temperature conditions during the impacts caused melting of the meteorites and the ambient crustal and mantle rocks,producing hybrid melts containing partially un-melted *** materials contributed to the elevated ^(187)Os/^(188)Os values,Re and Re/Os ratios,whereas the undifferentiated meteorite accounted for the increases in the PPGE/IPGE and decreased ^(187)Os/^(188)Os *** pressure and super-reduced phases were likely generated by this process and were subsequently transported into the newly formed mantle peridotites and chromitites of future *** remaining meteoritic and lithospheric fragments most likely sank deeper and were distributed widely in the convecting mantle to produce the observed global compositional heterogeneities.

关键词： Re-Os isotopes ophiolites PGE meteorites subduction initiation oceanic lithosphere

乡村振兴背景下大学生返乡创业政策评估与优化策略

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黑龙江高教研究 2025年第2期43卷 155-160页

作者：杨伟明栗麟李鑫深圳信息职业技术学院广东深圳518115 河南农业大学河南郑州450000 重庆工商大学重庆400067

大学生返乡创业是推进乡村振兴战略、缓解大学生就业压力的重要途径。基于大学生返乡创业政策文本,通过构建政策工具、发展阶段、利益相关主体的三维框架进行政策评估。研究发现,大学生返乡创业已经吸引了政府的持续关注和高度重视,环... 详细信息

大学生返乡创业是推进乡村振兴战略、缓解大学生就业压力的重要途径。基于大学生返乡创业政策文本,通过构建政策工具、发展阶段、利益相关主体的三维框架进行政策评估。研究发现,大学生返乡创业已经吸引了政府的持续关注和高度重视,环境型和供给型政策工具使用过度,而需求型政策工具使用不足;政策措施主要关注初创阶段和成长阶段,较少涉及成熟阶段;政策注意力主要集中在返乡创业者、返乡创业企业等核心利益主体上,较少关注金融机构、高校等次要利益主体。基于此,建议深度优化政策工具整体结构,增加需求型政策供给;强化政策措施与返乡创业生命周期匹配度,加大成熟期政策支持力度;协调兼顾各个参与主体的利益,推动金融机构、高校等利益相关主体为大学生返乡创业提供支持。

关键词：乡村振兴大学生返乡创业政策文本分析

多力场耦合条件下T型圆管通道内流体热混合机理研究

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西安交通大学学报 2025年第1期59卷 78-92页

作者：李桉琦苏博林梅王秋旺西安交通大学能源与动力工程学院西安710049

针对海洋动力平台和船舶动力装置中T型圆管通道内冷热流体间的热混合机理尚不清楚的问题,利用大涡模拟方法,对不同支管布置方式高温高压工况下(运行压力为10 MPa,进口流体温差为275 K,摇摆雷诺数为41 500)的多力场耦合T型圆管通道内流... 详细信息

针对海洋动力平台和船舶动力装置中T型圆管通道内冷热流体间的热混合机理尚不清楚的问题,利用大涡模拟方法,对不同支管布置方式高温高压工况下(运行压力为10 MPa,进口流体温差为275 K,摇摆雷诺数为41 500)的多力场耦合T型圆管通道内流体热混合机理进行数值研究。利用提出的混合系数定量评价了不同布置方式下T型圆管通道内流体混合效果,利用均方根温度定量评价了不同布置方式下T型圆管通道管壁处温度脉动情况。结果表明:剪切层和尾迹区内涡结构与温度场存在时间和空间上的协同机制,且涡脱落频率和温度脉动频率基本相同,脱落频率为19.3 Hz;附加惯性力引起T型圆管通道内涡结构和温度场在时间和空间上周期性变化,加速了流体混合过程,削弱了浮升力和重力引起的热分层现象,同时增大了流体域内温度波动,长度约为10.2 D(D为主管内径);与对应的静止工况相比,支管竖直向上、水平和竖直向下布置时,摇摆条件下混合系数分别增大了10.8%、18.3%和27.8%;摇摆条件竖直向下布置时,管壁处温度均方根峰值最大为0.16,约为静止工况的2倍。因此,支管竖直向上布置时,热混合效果最好,热分层现象最弱,在实际应用中应被优先考虑。

关键词： T型圆管通道浮升力摇摆条件热混合机理大涡模拟

Photocatalytic hydrogen production toward carbon neutrality:tracking charge separation

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National Science Review 2023年第9期10卷 9-10页

作者： Bao-Lian su Laboratory of Inorganic Materials Chemistry University of Namur State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

Under the vision of ’carbon peaking and carbon neutrality’,the global energy system is facing a deep *** a clean energy with the potential to achieve zero carbon emissions,hydrogen energy will undoubtedly play an important ***-energy-driven photo catalytic reactions can decompose water to produce hydrogen and reduce carbon dioxide to produce solar fuels.

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Microstructure and mechanical properties of 2219 aluminum alloy VPTIG welds during cyclic thermal treatment

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Rare Metals 2022年第10期41卷 3539-3545页

作者： Di-Yao su Hui-Jin Jin su-Jun Wu School of Materials Scienceand Engineering Beihang UniversityBeijing 100191China

In this study,the effect of the cyclic thermal treatment(CTT) on the microstructure and mechanical properties of the 2219 Al alloy welds fabricated using variable polarity tungsten inert gas(VPTIG) arc welding method were investigated by optical microscope(OM),transmission electron microscope(TEM),and low-temperature tensile tests,with emphasis on precipitation evolution and property variation in different areas of the *** of the microhardness profile across the weld reveals that there are maximum and minimum hardness values in the heat-affected zone(HAZ) adjacent to the fusion boundary(FB).It is found that the maximum hardness value increases with the temperature cycles of the cyclic thermal treatment due to the formation of GuinierPreston(GP) zones,while the microhardness at other positions remains *** results show that the CCT results in an increase in the yield strength,but a decrease in the ductility of the weld joint.

关键词： 2219 aluminum alloy VPTIG weld Microstructure Microhardness

Reduct and Attribute Order

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Journal of Computer Science & Technology 2004年第4期19卷 429-449页

作者： su-QingHan JueWang LaboratoryofComplexSystemsandIntelligenceScience InstituteofAutomationTheChineseAcademyofSciencesBeijing100080P.R.China

Based on the principle of discernibility matrix, a kind of reduction algorithm with attribute order has been developed and its solution has been proved to be complete for reduct and unique for a given attribute order. Being called the reduct problem, this algorithm can be regarded as a mapping R = Reduct(S) from the attribute order space Theta to the reduct space R for an information system , where U is the universe and C and D are two sets of condition and decision attributes respectively. This paper focuses on the reverse problem of reduct problem S = Order(R), i.e., for a given reduct R of an information system, we determine the solution of S = Order(R) in the space Theta. First, we need to prove that there is at least one attribute order S such that S = Order(R). Then, some decision rules are proposed, which can be used directly to decide whether the pair of attribute orders has the same reduct. The main method is based on the fact that an attribute order can be transformed into another one by moving the attribute for limited times. Thus, the decision of the pair of attribute orders can be altered to the decision of the sequence of neighboring pairs of attribute orders. Therefore, the basic theorem of neighboring pair of attribute orders is first proved, then, the decision theorem of attribute order is proved accordingly by the second attribute.

关键词： reduct attribute order rough set

基于“配音秀”APP短视频配音在国际中文中级口语教学中的应用

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语言与文化研究

语言与文化研究 2025年第1期33卷 123-126页

作者：尹娜苏鑫临沂大学临沂276005

随着互联网的发展和数字化教育的普及,数字化学习资源越来越多地融入到了语言教学中去。其中,“配音秀”APP的配音功能为国际中文口语教学带来了新的视角。在此前的研究中发现,将配音引入到教学中去,大都以影视剧或电影片段配音的方式为... 详细信息

随着互联网的发展和数字化教育的普及,数字化学习资源越来越多地融入到了语言教学中去。其中,“配音秀”APP的配音功能为国际中文口语教学带来了新的视角。在此前的研究中发现,将配音引入到教学中去,大都以影视剧或电影片段配音的方式为主,而短视频配音的方式则比较少见。因此文章主要探讨如何基于“配音秀”APP,将短视频配音和国际中文中级口语教学结合在一起,为国际中文教学提供新的思路和方法。

关键词： “配音秀” 国际中文教育中级口语教学短视频配音

Powerful qua-functional electrolyte additive for lithium metal batteries

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Green Energy & Environment 2022年第3期7卷 361-364页

作者： Dawei su School of Mathematical and Physical Science Faculty of ScienceUniversity of Technology SydneyNSW2000Australia

Lithium metal batteries(LMBs) have attracted tremendous research attention because of the high theoretical capacity(3860 mAh g^(-1)) and the lowest electrochemical potential(-3.04 V *** hydrogen electrode).However,the Lithium dendrites,forming from plating/stripping processes,cause the excessive consumption of electrolyte and active Li and the puncture on the *** limits the commercialization of ***,Ma’s group proposed heptafluorobutyric anhydride(HFA) as qua-functional electrolyte additive and verified the protection mechanism from the structure and electrochemical *** results creatively put forward qua-functional electrolyte additive for the improvement of LMBs and provides good experience for the exploration of multi-functional additive,inspiring researchers to explore new multi-functional electrolyte additives in future.

关键词： electrolyte additive lithium

Higgs assisted razor search for Higgsinos at a 100 TeV pp collider

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Science China(Physics,Mechanics & Astronomy) 2020年第10期63卷 62-70页

作者： Adarsh Pyarelal ShuFang su School of Information University of ArizonaTucson AZ 85721USA Department of Physics University of ArizonaTucson AZ 85718USA

A 100 TeV proton-proton collider will be an extremely effective way to probe the electroweak sector of the minimal supersymmetric standard model(MSSM).In this paper,we describe a search strategy for discovering pair-produced Higgsino-like next-to-lightest supersymmetric particles(NLSPs)at a 100 TeV hadron collider that decay to Bino-like lightest supersymmetric particles(LSPs)via intermediate Z and SM Higgs bosons that in turn decay to a pair of leptons and a pair of b-quarks respectively:˜χ02˜χ03→(Z˜χ01)(h˜χ01)→b bℓℓ+˜χ01˜χ*** addition,we examine the potential for machine learning techniques to boost the power of our *** this analysis,Higgsinos up to 1.4 TeV can be discovered at the 5σlevel for Binos with mass of about 0.9 TeV using 3000 fb−1 of ***,Higgsinos up to 1.8 TeV can be excluded at 95%*** Binos with mass of about 1.4 *** search channel extends the multi-lepton search limits,especially in the region where the mass difference between the Higgsino NLSPs and the Bino LSP is small.

关键词： new physics dark matter supersymmetry