检索结果-南通市图书馆

Tungsten 2020年第4期2卷 381-389页

作者： Ke Jing Chao Zhang Rui Liu Zhuo‑Ming Xie Lin‑Chao Zhang Li‑Feng Zhang Jun Liu Rui Gao Jun‑Feng Yang Xian‑Ping Wang Ting hao Xue‑Bang Wu Qian‑Feng Fang chang‑hao liang Guang‑Nan Luo You‑Yun Lian Xiang Liu chang‑Song Liu Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China Southwestern Institute of Physics Chengdu 610041China

Zirconium carbide(ZrC)nanoparticles with an average size of 5.6 nm were synthesized through laser fragmentation(LF)from as-received 20-60 nm ZrC particles,and LF-ZrC nanoparticle dispersion-strengthened tungsten(LF-WZC)samples were fabricated by spark plasma sintering *** average grain size of LF-WZC is 1.91μm and most ZrC particles in LF-WZC are smaller than 10 ***-WZC exhibits finer grain size,higher yield strength and hardness but lower ductility as compared with W-ZrC samples using as-received ZrC(WZC).The results showed that finer ZrC nanoparticles dispersed in tungsten can enhance the strength by hindering the motion of dislocations,but they may also introduce stress concentra-tion and thus reduce the *** thermal shock resistance of the WZC and LF-WZC samples was investigated using an electron beam *** LF-WZC sample also exhibits a higher cracking threshold(0.33-0.44 GW·m^(−2))than WZC(0.22-0.33 GW·m^(−2))at room *** enhanced thermal shock resistance of LF-WZC could be attributed to its high yield strength.

关键词： Tungsten Mechanical properties ZrC Laser fragmentation Thermal shock resistance

数字经济、绿色技术创新与碳排放强度--基于我国城市面板数据的经验研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

商业研究 2023年第2期 73-80页

作者：常皓亮中国社会科学院大学应用经济学院北京102488

数字经济和绿色技术创新将是新时代驱动中国实现绿色低碳转型的“双引擎”,本文以2011-2019年中国279个地级及以上城市为样本,考察数字经济对碳排放强度的影响。结果表明:数字经济发展能够显著降低碳排放强度;现阶段数字经济能够促进绿... 详细信息

数字经济和绿色技术创新将是新时代驱动中国实现绿色低碳转型的“双引擎”,本文以2011-2019年中国279个地级及以上城市为样本,考察数字经济对碳排放强度的影响。结果表明:数字经济发展能够显著降低碳排放强度;现阶段数字经济能够促进绿色技术创新水平提升,并且绿色技术创新对于碳排放强度的净效应为促减效应;数字经济对碳排放强度的影响存在“边际效应”递减的非线性特征,即数字经济发展水平提高,对碳排放强度的抑制效果显著降低,但是绿色技术创新能够有效减缓“边际效应”递减的速度;异质性分析发现,数字经济的减排效果在中部城市、外围城市和资源型城市更为显著。

关键词：数字经济绿色技术创新碳排放强度非线性效应

基于细粒度污点跟踪策略的Android应用敏感信息泄露检测

在线全文

学校读者我要写书评

暂无评论

北京邮电大学学报 2016年第3期39卷 16-21页

作者：杨天长崔浩亮牛少彰宋文北京邮电大学智能通信软件与多媒体北京市重点实验室北京100876

针对Android应用存在的敏感信息泄露问题,基于细粒度信息流跟踪策略,利用静态污点跟踪技术设计了一个Android应用敏感信息泄露检测方案.该方案根据Smali代码的语法语义特点、应用内部的函数调用关系及Android通信机制建立了细粒度的污... 详细信息

针对Android应用存在的敏感信息泄露问题,基于细粒度信息流跟踪策略,利用静态污点跟踪技术设计了一个Android应用敏感信息泄露检测方案.该方案根据Smali代码的语法语义特点、应用内部的函数调用关系及Android通信机制建立了细粒度的污点传播策略,用不同的泄露检测策略和污点传播策略来驱动检测过程,根据跟踪结果确定应用是否存在敏感信息泄露.实验结果表明该方案能够对敏感信息泄露进行有效检测,增加了检测的准确性和灵活性,减少了分析过程中存在的信息流不全面和误报问题.

关键词：信息流污点跟踪敏感信息信息泄露

数字经济可以增强产业链安全吗?——基于世界投入产出表的研究

在线全文

学校读者我要写书评

暂无评论

经济体制改革 2023年第3期 15-24页

作者：陈晓东常皓亮中国社会科学院工业经济研究所(中国社会科学院中国产业与企业竞争力研究中心) 北京100006 中国社会科学院大学应用经济学院北京102488

基于2002~2014年世界投入产出表,研究数字经济对产业链安全的影响效应,研究发现:数字经济对于产业链安全的增强确实起到一定的积极作用;在数字化软件和服务方面,高端软件以及高级信息服务进口依赖性成为制约我国产业链安全水平提升的因... 详细信息

基于2002~2014年世界投入产出表,研究数字经济对产业链安全的影响效应,研究发现:数字经济对于产业链安全的增强确实起到一定的积极作用;在数字化软件和服务方面,高端软件以及高级信息服务进口依赖性成为制约我国产业链安全水平提升的因素;数字经济的影响具有行业异质性,数字经济对传统制造业产业链安全呈现显著负效应。鉴于此,应加强数字基础设施建设,增加数字技术投入,优化数据要素市场化配置,促进资源型数字经济发展和增强产业链柔性,推动数字经济与实体经济融合,加快软件和信息技术服务开放,强化信息安全保障体系建设,以维护数字经济安全和产业链稳定。

关键词：数字经济产业链安全投入产出表

Android应用Intent通信风险分析及检测

在线全文

学校读者我要写书评

暂无评论

北京理工大学学报 2017年第6期37卷 625-630,636页

作者：杨天长崔浩亮牛少彰黄振鹏北京邮电大学计算机学院北京100876

针对Android应用Intent通信可能导致的安全风险,设计了基于动静结合的安全威胁检测方法.静态分析阶段检测应用中请求的内部和外部组件并判断组件是否存在被劫持的风险,然后对存在利用Extra属性进行数据传输的Intent对象利用污点跟踪确... 详细信息

针对Android应用Intent通信可能导致的安全风险,设计了基于动静结合的安全威胁检测方法.静态分析阶段检测应用中请求的内部和外部组件并判断组件是否存在被劫持的风险,然后对存在利用Extra属性进行数据传输的Intent对象利用污点跟踪确定是否存在数据和权限泄露;动态测试阶段根据静态分析检测到的Intent对象构造Fuzzing测试数据,发送测试指令给测试对象并收集应用的执行日志,确定是否存在拒绝服务风险.实验结果表明检测方法可以有效和全面地检测由Intent通信导致的安全缺陷.

关键词：组件劫持 Intent 数据泄露拒绝服务

MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self‑Powered Motion Sensing

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第3期17卷 265-279页

作者： Yu‑Ze Wang Yu‑chang Wang Ting‑Ting Liu Quan‑liang Zhao Chen‑Sha Li Mao‑Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx(MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

石墨烯/聚酰亚胺复合膜热导率的分子动力学模拟（英文）

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

新型炭材料 2018年第3期33卷 213-220页

作者：徐京城戴思畅李昊亮杨俊和上海理工大学材料科学与工程学院上海200093 上海材料创新研究院上海200444

石墨化聚酰亚胺条带可作为连接石墨烯的桥梁,形成大尺度石墨烯复合薄膜。采用opt-Tersoff分子力场和非平衡分子动力学方法,计算研究了石墨烯和石墨烯/聚酰亚胺复合膜热导率的尺寸效应。结果发现,石墨烯的热导率与模型的长度相关,增加聚... 详细信息

石墨化聚酰亚胺条带可作为连接石墨烯的桥梁,形成大尺度石墨烯复合薄膜。采用opt-Tersoff分子力场和非平衡分子动力学方法,计算研究了石墨烯和石墨烯/聚酰亚胺复合膜热导率的尺寸效应。结果发现,石墨烯的热导率与模型的长度相关,增加聚酰亚胺条带的数目或宽度可提高石墨烯/聚酰亚胺复合膜的导热性能,而增加聚酰亚胺条带的长度作用不大。另外,计算了声子态密度用于解释复合膜结构引起的热导率差异。

关键词：分子动力学热导率石墨烯聚酰亚胺分子焊接

在线全文

学校读者我要写书评

暂无评论

钢结构工程监理控制要点和对策

新乡学院学报 2009年第2期26卷 79-80页

作者：王云磊郝长亮河南天正建设工程咨询管理有限公司河南新乡453000

结合钢结构工程监理工作实践,分析了监理工作的重点和难点,讨论了钢结构工程监理的控制要点和对策,以利于监理工程师进行质量控制。

关键词：钢结构工程监理控制工程监理

Recent progress on photoactive nonprecious transition-metal complexes

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期 46-95页

作者： Zhong-liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen chang-Jiang Yao Yuan-Yuan Zhu liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词：

同方期刊数据库

MLDA:a multi-level k-degree anonymity scheme on directed social network graphs

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2024年第2期18卷 199-215页

作者： Yuanjing hao Long LI liang chang Tianlong GU Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China Engineering Research Center of Trustworthy AI(Ministry of Education) Jinan UniversityGuangzhou 510632China

With the emergence of network-centric data,social network graph publishing is conducive to data analysts to mine the value of social networks,analyze the social behavior of individuals or groups,implement personalized recommendations,and so ***,published social network graphs are often subject to re-identification attacks from adversaries,which results in the leakage of users’***-anonymity technology is widely used in the field of graph publishing,which is quite effective to resist re-identification ***,the current researches still exist some issues to be solved:the protection of directed graphs is less concerned than that of undirected graphs;the protection of graph structure is often ignored while achieving the protection of nodes’identities;the same protection is performed for different users,which doesn’t meet the different privacy requirements of ***,to address the above issues,a multi-level-degree anonymity(MLDA)scheme on directed social network graphs is proposed in this ***,node sets with different importance are divided by the firefly algorithm and constrained connectedness upper approximation,and they are performed different-degree anonymity protection to meet the different privacy requirements of ***,a new graph anonymity method is proposed,which achieves the addition and removal of edges with the help of fake *** addition,to improve the utility of the anonymized graph,a new edge cost criterion is proposed,which is used to select the most appropriate edge to be ***,to protect the community structure of the original graph as much as possible,fake nodes contained in a same community are merged prior to fake nodes contained in different *** results on real datasets show that the newly proposed MLDA scheme is effective to balance the privacy and utility of the anonymized graph.

关键词： directed social network graph graph publishing k-degree anonymity community structure graph utility