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Positive effect of Mo on mechanical properties of a Ni-42W-10Co-x Mo medium heavy alloy

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China Foundry 2025年

作者： Guo-xin Cao Jian-xin Dong Yong-sheng He He Jiang Fang Hao Zhi-hua Nie Teng-fei Ma bao-quan Fu School of Materials Science and Engineering University of Science and Technology Beijing Xi'an Superalloy Technology Co. Ltd. School of Materials Science and Engineering Beijing Institute of Technology Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou University

In this study,a novel Ni-W-Co-Mo medium heavy alloy (MHA) was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-xM o alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypoeutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-xM o alloys is Mo-induced solid solution strengthening and precipitation strengthening.

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A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu Ming-Hui Chen Peng Zhao Wen-Bo Deng Ji Xiong Kai Guo Ya-Qing Feng bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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碳纳米管改性混凝土的应力应变与动态强度研究

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合成纤维 2025年第1期54卷 86-90页

作者：范宝宝中煤科工集团北京华宇工程有限公司北京100120

为深入探究碳纳米管(CNTs)对混凝土不同受力阶段的增强效果,利用100 mm直径的分离式霍普金森压杆试验,研究冲击速度、CNTs含量等因素对混凝土韧性和抗冲击性能的影响。试验结果表明:CNTs的加入对水泥基材料的冲击性能有显著的改善作用,... 详细信息

为深入探究碳纳米管(CNTs)对混凝土不同受力阶段的增强效果,利用100 mm直径的分离式霍普金森压杆试验,研究冲击速度、CNTs含量等因素对混凝土韧性和抗冲击性能的影响。试验结果表明:CNTs的加入对水泥基材料的冲击性能有显著的改善作用,动态抗压强度、动态强度增大因子随冲击速度的增加而呈直线上升;在同一加载程度下,随CNTs含量的增大,水泥基材料的动态抗压强度先增大后减小,最大增幅可达23.7%;在混凝土中加入适量的CNTs,能够提高混凝土的整体强度、致密性,进而提高其动态力学性能。

关键词：碳纳米管混凝土霍普金森压杆应力应变动态强度

应对供应中断风险下消费者恐慌囤货行为:涨价策略与限购策略

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管理工程学报 2025年第2期39卷 118-129页

作者：郑锐王宇鲍丽娜武汉理工大学安全科学与应急管理学院湖北武汉430070 武汉理工大学中国应急管理研究中心湖北武汉430070 浙江大学管理学院浙江杭州310058

本文研究了零售商应对供应中断风险下消费者恐慌囤货行为的涨价策略与限购策略。研究模型考虑一个垄断零售商在两个订货周期内向市场销售一种生活必需品,第二期的供应中断风险可能导致消费者在第一期发生恐慌囤货。研究基于对消费者恐... 详细信息

本文研究了零售商应对供应中断风险下消费者恐慌囤货行为的涨价策略与限购策略。研究模型考虑一个垄断零售商在两个订货周期内向市场销售一种生活必需品,第二期的供应中断风险可能导致消费者在第一期发生恐慌囤货。研究基于对消费者恐慌囤货决策模型的刻画,分析了消费者恐慌囤货行为如何影响零售商利润以及社会总福利,然后进一步分析了零售商分别在什么条件下应采取涨价策略或限购策略以及这些策略将如何影响社会总福利。研究结果表明:(1)当零售商拥有足够的库存时,一定程度的恐慌囤货可以增加零售商利润和社会总福利;而当恐慌囤货导致零售商严重缺货时,恐慌囤货将损害零售商利润和社会总福利。(2)当零售商需要采取策略应对消费者恐慌囤货行为时,存在一个消费者恐慌强度的阈值,当恐慌强度低于阈值时,零售商应采取涨价策略调节消费者的囤货需求;当恐慌强度高于阈值时,零售商应采取限购策略限制消费者的囤货。(3)零售商不同的应对策略对社会总福利有不同的影响,当恐慌强度非常高时,采取限购策略可以显著改善社会总福利;采取涨价策略可以提高零售商的备货动机,在一定条件下可以改善社会总福利。

关键词：供应链管理供应中断风险恐慌囤货需求管理限购策略

跨越新生适应障碍:中国大学入学教育的运行机制及其成效

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华东师范大学学报（教育科学版） 2025年第1期43卷 49-66页

作者：鲍威何元皓何峰厦门大学高等教育发展中心厦门361005 厦门大学教育研究院厦门361005 北京大学教育经济研究所北京100871 北京大学未来教育管理研究中心北京100871 北京大学研究生院北京100871

入学教育是帮助新生适应大学环境、形成自我与社会认知、充分融入大学生活的重要桥梁。鉴于我国大学新生普遍存在学术性、社会性双重适应障碍,在通过国际比较清晰认识中国入学教育运行机制特征的基础上,利用全国大一学生调查数据,科学... 详细信息

入学教育是帮助新生适应大学环境、形成自我与社会认知、充分融入大学生活的重要桥梁。鉴于我国大学新生普遍存在学术性、社会性双重适应障碍,在通过国际比较清晰认识中国入学教育运行机制特征的基础上,利用全国大一学生调查数据,科学评估入学教育在缓减新生适应障碍中的干预成效。研究表明,采用长期深度教育形式,传递专业学科认知、学习方法习得、心理健康建设3大教育内容向度的入学教育运行机制,对缓减学生学术性、社会性双重适应障碍具有积极效用。囿于精准化帮扶举措欠缺,入学教育对弱势学生的补偿效应有待加强。结论为完善大学入学教育、保障人才培养质量提供科学启示。

关键词：入学教育大学新生学术性适应社会性适应

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大模型红队测试研究综述

计算机科学 2025年第1期52卷 34-41页

作者：包泽芃钱铁云武汉大学计算机学院武汉430072

大模型红队测试(Large Model Red Teaming)旨在让大语言模型(Large Language Model, LLM)接收对抗测试,从而诱使模型输出有害的测试用例,进而发现模型中的漏洞并提高其鲁棒性。大模型红队测试是大模型领域的前沿课题,近年来受到学术界... 详细信息

大模型红队测试(Large Model Red Teaming)旨在让大语言模型(Large Language Model, LLM)接收对抗测试,从而诱使模型输出有害的测试用例,进而发现模型中的漏洞并提高其鲁棒性。大模型红队测试是大模型领域的前沿课题,近年来受到学术界和工业界的广泛关注。研究者们针对大模型红队测试提出了众多解决方案,并在模型对齐上取得了一定进展。然而,受限于大模型红队数据的短缺和评价标准的模糊,现有研究大多局限于针对特定的场景进行评估。文中首先从与大模型安全相关的定义出发,对其所涉及的各种风险进行阐述;其次,针对大模型红队测试的重要性及其主要类别进行了阐述,综述和分析了相关红队技术的发展历程,并介绍了已有的数据集和评价指标;最后,对大模型红队测试的未来发展趋势进行了展望和总结。

关键词：红队大模型安全强化学习语言模型越狱

Anisotropic transport properties and topological Hall effect in the annealed kagome antiferromagnet FeGe

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Jiajun Ma Chenfei Shi Yantao Cao Yuwei Zhang Yazhou Li Jiaxing Liao Jialu Wang Wenhe Jiao Hanjie Guo Chenchao Xu Shixun Cao Jianhui Dai Jin-Ke bao Yuke Li School of Physics Hangzhou Key Laboratory of Quantum Matters Hangzhou Normal University Department of Physics Materials Genome Institute and International Center for Quantum and Molecular StructuresShanghai University Songshan Lake Materials Laboratory School of Physical Science and Technology Lanzhou University Key Laboratory of Quantum Precision Measurement of Zhejiang Province Department of Applied PhysicsZhejiang University of Technology

Electron correlation often gives birth to various orders in quantum materials. Recently, a strongly correlated kagome antiferromagnet FeGe is discovered to undergo a charge density wave transition inside the A-type antiferromagnetic state, providing an opportunity to explore the interplay between charge order and magnetism. Here, we reported the observation of anisotropic resistivity and Hall effect, along with a topological Hall effect, in the annealed FeGe crystals. As the current flows along the abplane, the temperature dependence of ρabexhibits a distinct resistivity loop related to a first-order transition at Tcdw. The applied magnetic fields do not alter Tcdwbut can induce a spin-flop transition at Hsf. Consequently, a field-induced large topological Hall effect is observed in the canting antiferromagnetic（CAFM） state below Tcant, which is possibly attributed to the non-trivial spin texture during the spin-flop process. Whereas, as current is parallel to c-axis, both the field-induced transitions in ρcand χcdisappear. Instead, the Hall resistivity in the annealed FeGe significantly exhibits a deviation from the linear *** findings provide valuable insight into revealing the interplay among magnetism, charge order and topology in the kagome magnets.

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Investigating impacts of different building contents on the post-earthquake evacuation time using an agent-based model with considering turning behavior

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 939-955页

作者： bao Yu School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park of Wuhan University of Technology Sanya 572025China

Accurate assessment of crowd evacuation inside the post-earthquake environment is critical from many perspectives,but this issue receives much less attention compared to the seismic losses of structural and non-structural *** could be attributed to the fact that post-earthquake evacuation analysis is complex due to the interaction between human behavior and the actual built environment induced by different building *** study attempts to tackle this problem by investigating the impacts of different building contents on post-earthquake evacuation time by using an agent-based model that considers turning *** this end,the agent-based model is first described,including:properties of the agent-based model with turning behavior,key aspects in its formulation considering different evacuation stages,and influence of different building contents(namely,debris from partition walls and ceiling systems,and various types of equipment)on the agent’s ***,a school building is used as a benchmark problem to validate the model without earthquake,and the findings indicate that the agent-based model can match the real safety drill results reasonably *** the validation,the school building is subsequently designed in accordance with modern seismic design codes,and the influence of debris and equipment on post-earthquake evacuation time is quantitatively studied using a suite of pulse-type ground motions as *** on this case study,recommendations are made for structural and architectural designers in an effort to reduce the potential evacuation ***,debris induced by partition walls or ceiling systems should be controlled as it has the greatest impact on the total evacuation time.

关键词： seismic fragility evacuation agent-based model route choice built environment

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产教融合背景下地方高校高质量发展的探赜

黑龙江高教研究 2025年第2期43卷 29-34页

作者：刘宝臣秦福利广西科技大学广西柳州545006

地方高校是我国高等教育序列中的主体,在高等教育普及化阶段,地方高校高质量发展对于推进高等教育强国建设和新质生产力发展具有重要作用。产教融合作为推进教育、科技、人才一体化建设的重要举措,能够促进产业和教育的双向赋能,对于地... 详细信息

地方高校是我国高等教育序列中的主体,在高等教育普及化阶段,地方高校高质量发展对于推进高等教育强国建设和新质生产力发展具有重要作用。产教融合作为推进教育、科技、人才一体化建设的重要举措,能够促进产业和教育的双向赋能,对于地方高校更具独特意义和深刻的时代内涵。产教融合的教育理念和实践方式对地方高校的办学定位、学科专业、人才培养、社会服务、治理体系具有正向作用,相应地提出了促进地方高校高质量发展的五点举措。

关键词：产教融合地方高校高质量发展赋能