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Fortifying Smart Grids: A Holistic Assessment Strategy against Cyber Attacks and Physical Threats for Intelligent Electronic Devices
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作者 Yangrong Chen June li +4 位作者 Yu Xia Ruiwen Zhang lingling li Xiaoyu li lin Ge 《Computers, Materials & Continua》 SCIE EI 2024年第8期2579-2609,共31页
Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightene... Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightened security challenges within smart grids,IEDs pose significant risks due to inherent hardware and software vulner-abilities,as well as the openness and vulnerability of communication protocols.Smart grid security,distinct from traditional internet security,mainly relies on monitoring network security events at the platform layer,lacking an effective assessment mechanism for IEDs.Hence,we incorporate considerations for both cyber-attacks and physical faults,presenting security assessment indicators and methods specifically tailored for IEDs.Initially,we outline the security monitoring technology for IEDs,considering the necessary data sources for their security assessment.Subsequently,we classify IEDs and establish a comprehensive security monitoring index system,incorporating factors such as running states,network traffic,and abnormal behaviors.This index system contains 18 indicators in 3 categories.Additionally,we elucidate quantitative methods for various indicators and propose a hybrid security assessment method known as GRCW-hybrid,combining grey relational analysis(GRA),analytic hierarchy process(AHP),and entropy weight method(EWM).According to the proposed assessment method,the security risk level of IEDs can be graded into 6 levels,namely 0,1,2,3,4,and 5.The higher the level,the greater the security risk.Finally,we assess and simulate 15 scenarios in 3 categories,which are based on monitoring indicators and real-world situations encountered by IEDs.The results show that calculated security risk level based on the proposed assessment method are consistent with actual simulation.Thus,the reasonableness and effectiveness of the proposed index system and assessment method are validated. 展开更多
关键词 Smart grid intelligent electronic device security assessment abnormal behaviors network traffic running states
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Differential expression of miRNAs and mRNAs in the livers of largemouth bass Micropterus salmoides under heat stress
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作者 Xuqian ZHAO Zijie liN +4 位作者 Caijuan li Hao ZHU lingling li Wenjia MAO Qufei liNG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期594-608,共15页
Global warming threatens freshwater ecosystems and compromises fish survival.To elucidate the role of miRNAs in the livers of heat stressed largemouth bass,juvenile fish was subject to heat stress under 37°C.Both... Global warming threatens freshwater ecosystems and compromises fish survival.To elucidate the role of miRNAs in the livers of heat stressed largemouth bass,juvenile fish was subject to heat stress under 37°C.Both mRNA-seq and miRNA-seq were conducted on the liver tissues under control and heat stress conditions.Differential gene expression analysis and enrichment analysis were performed on mRNA and miRNA expression profiles.A total of 406 differentially expressed genes(DEGs)were discovered,of which 212 were up-regulated and 194 were down-regulated.Most of the DEGs were significantly implicated in the regulation of“protein processing in endoplasmic reticulum”,“proteasome”,“steroid biosynthesis”,and“ornithine decarboxylase inhibitor activity”pathways.In addition,47 differentially expressed miRNAs(DEMs)were identified in largemouth bass livers under heat stress,including 21 up-regulated and 25 down-regulated miRNAs.A negatively regulated miRNA-mRNA network including 12 miRNAs and 19 mRNAs was constructed with DEMs involved in“protein degradation”,“calcium ion regulation”,“cell apoptosis”,and“lipid metabolism”.Moreover,this study indicated novel-miR-144 activated the IRE1 signaling pathway by targeting txndc5 to induce liver apoptosis in largemouth bass under heat stress.This study revealed the involvement of miRNA regulation in largemouth bass in response to heat stress. 展开更多
关键词 heat stress largemouth bass miRNA-mRNA interaction
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引入逆向思维和设计理念的有机合成实验教学改革——以基于逆合成分析法的肉桂酸合成为例
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作者 郑媛 兰泉 +3 位作者 查正根 李玲玲 蒋俊 朱平平 《大学化学》 CAS 2024年第6期207-213,共7页
以经典有机化学实验项目——肉桂酸的合成为例,介绍在有机合成实验教学中引入逆向思维的教学设计,经改进后,实验融入了丰富的思政元素,逆向推理思维模式的引入,避免了“照方抓药”式的实验教学;学生通过探究多条合成路线构建目标分子,... 以经典有机化学实验项目——肉桂酸的合成为例,介绍在有机合成实验教学中引入逆向思维的教学设计,经改进后,实验融入了丰富的思政元素,逆向推理思维模式的引入,避免了“照方抓药”式的实验教学;学生通过探究多条合成路线构建目标分子,进一步加深了对有机合成内涵的理解;本项目融入了三项诺贝尔化学奖成果,确保了教学内容的前沿性和先进性。 展开更多
关键词 逆合成分析 有机合成实验 诺贝尔奖成果 逆向推理思维模式 肉桂酸的合成
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Why Teaching and Research Activities Lack Vitality?:A Probe into the Basic Psychological Needs of Teachers
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作者 Shenwei Jiang lingling li Yang Cui 《Journal of Contemporary Educational Research》 2023年第1期33-39,共7页
Teaching and research activities are of great significance to the professional development of teachers.The basic psychological needs of teachers include autonomy,competence,and attribution.The engagement of teachers i... Teaching and research activities are of great significance to the professional development of teachers.The basic psychological needs of teachers include autonomy,competence,and attribution.The engagement of teachers in teaching and research activities can be analyzed from these three perspectives.Under the management system of teaching and research,teachers generally lack autonomy in the organization of teaching and research activities;they are also lack scientific research knowledge and ability;in addition,under the influence of harmonious interpersonal relationships and the culture of individualism,there is a dearth in real communication among teachers.In light of this,we propose targeted countermeasures to promote the vitality of teaching and research activities. 展开更多
关键词 Teaching and research activities VITALITY TEACHERS Basic psychological needs
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簇-金属氧化物助剂电子相互作用调控的Ru原子簇催化剂用于温和条件下合成氨反应
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作者 张天华 胡海慧 +15 位作者 李嘉欣 高迎龙 李玲玲 张明远 彭渲北 周岩良 倪军 林炳裕 林建新 朱兵 吴冬霜 张林杰 韩丽丽 郑黎荣 王秀云 江莉龙 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第5期209-218,共10页
氨是重要的化肥原料,也是颇具潜力的氢能源载体,对于可再生能源的储存、运输和终端利用至关重要.然而,传统Haber-Bosch工艺合成氨的反应条件苛刻,需要高温高压条件,并消耗大量化石能源及排放大量二氧化碳.可再生能源电解水制氢耦合温和... 氨是重要的化肥原料,也是颇具潜力的氢能源载体,对于可再生能源的储存、运输和终端利用至关重要.然而,传统Haber-Bosch工艺合成氨的反应条件苛刻,需要高温高压条件,并消耗大量化石能源及排放大量二氧化碳.可再生能源电解水制氢耦合温和合成氨新技术(eHB),不仅能实现可再生能源电力的“消纳和调峰”,而且可进行低成本、跨地域长距离存储运输,并可将“绿氨”与氢能产业相结合.然而,现有的高温高压合成氨催化剂与eHB工艺相不匹配,因此,迫切需要开发温和条件下高效合成氨催化剂技术,以实现可再生能源电力电解制氢体系和合成氨技术互补融合.目前,虽然助剂对于Ru基纳米簇(≥1 nm)合成氨催化剂的影响规律已得到了广泛研究,但它们对于Ru原子簇催化剂的作用机制尚不清楚,需要进一步揭示.本文考察了Ba及Ce助剂对Ru原子簇催化剂的影响规律,并分析了其作用机制.首先,通过简单的浸渍法将Ba和/或Ce物种掺杂到Ru原子簇催化剂(2 wt%Ru ACCs),制得Ba/Ce/2 wt%Ru ACCs催化剂;然后,通过一系列实验考察了这些催化剂的合成氨性能,并利用多种表征手段对其进行了深入分析.合成氨性能测试结果表明,添加Ba和Ce助剂后,2 wt%Ru ACCs催化剂的合成氨速率明显提高,在400℃和1 MPa下,Ba/Ce/2 wt%Ru ACCs催化剂的合成氨反应速率达到56.2 mmolNH_(3) gcat^(-1) h^(-1),是2 wt%Ru ACCs的7.5倍,且催化剂表现出较好的稳定性,在稳定运行140 h后活性未见明显降低.球差校正电子显微镜和X射线吸收精细结构谱结果表明,负载Ba和/或Ce后,Ru以Ru_(3)原子簇形式存在.X射线吸收近边结构谱和X射线光电子能谱结果表明,Ru与Ba及Ce物种之间存在较强的簇-金属氧化物助剂电子相互作用,可促进电子转移到Ru物种,形成富电子状态的Ru,进而促使电子转移到N_(2)的p*反键轨道,提高温和条件下合成氨反应速率.利用25%N_(2)+75%D_(2)气氛下的原位红外光谱研究催化剂的合成氨反应机理,结果表明,在Ba/Ce/2 wt%Ru ACCs催化剂表面同时检测到N_(2)D_(2)物种和N_(2)D_(x)物种的振动吸收峰,说明添加Ba和/或Ce物种没有改变Ru原子簇催化剂活化N_(2)的方式,N_(2)仍是通过加氢的路径合成氨.综上,本文考察了助剂对Ru原子簇的影响规律,揭示了其作用机制,为设计高效的温和条件合成氨催化剂提供参考. 展开更多
关键词 原子簇 助剂 N_(2)活化 合成氨 电子相互作用
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食品王国大讲堂——“颜”之有理
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作者 方思敏 吴红 +4 位作者 盛思哲 李玲玲 王钰熙 李红春 蒋俊 《大学化学》 CAS 2024年第9期177-182,共6页
以童话故事的形式,运用生动有趣的形象,通俗易懂的语言,由浅入深地引导人们透过植物性食品色彩丰富的外表以及常见的变色现象探寻其中蕴含的科学原理,从而帮助人们知其然更能知其所以然,加深对植物性食品中主要色素(叶绿素、类胡萝卜素... 以童话故事的形式,运用生动有趣的形象,通俗易懂的语言,由浅入深地引导人们透过植物性食品色彩丰富的外表以及常见的变色现象探寻其中蕴含的科学原理,从而帮助人们知其然更能知其所以然,加深对植物性食品中主要色素(叶绿素、类胡萝卜素、花青素)结构与性质(溶解性与稳定性)的认识,增强对酶促褐变的原理以及阻褐方法的了解,建立对着色剂等食品添加剂的正确观念。 展开更多
关键词 色素 性质 酶促褐变 植物性食品 着色剂
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“厨房化学”通识教育课程的构建与实施
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作者 方思敏 吴红 +4 位作者 李玲玲 王钰熙 李红春 蒋俊 张国庆 《大学化学》 CAS 2024年第10期396-401,共6页
通识教育是高校教育的重要组成部分,是德智体美劳五育并举的人才培养重要途径。“厨房化学”是面向我校本科生开设的化学类通识教育课程。课程融合学科知识,贴近日常生活,打造兼具学术性与趣味性的全新内容;构建多维考核体系,注重过程... 通识教育是高校教育的重要组成部分,是德智体美劳五育并举的人才培养重要途径。“厨房化学”是面向我校本科生开设的化学类通识教育课程。课程融合学科知识,贴近日常生活,打造兼具学术性与趣味性的全新内容;构建多维考核体系,注重过程性考核与综合能力评判,并引入学生互评环节。该课程有效激发学生学习化学的积极性,提升化学素养,增强综合素质,同时助力科普教育发展,取得良好的教学成效。 展开更多
关键词 厨房化学 通识课程 课程建设 教学成效
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走进量子点的奇妙世界
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作者 何苗苗 葛志青 +5 位作者 周强 何家庆 弓弘 李玲玲 朱平平 邵伟 《大学化学》 CAS 2024年第6期231-237,共7页
量子点材料,由于其受激发光、发射半峰宽窄、发光颜色连续可调等优良的性能,近些年来受到人们越来越多的关注,并拓展了很多相关方面的研究。本文从材料元素组成的角度简单介绍了量子点的类型及其在LED、太阳能电池、生物医用以及重金属... 量子点材料,由于其受激发光、发射半峰宽窄、发光颜色连续可调等优良的性能,近些年来受到人们越来越多的关注,并拓展了很多相关方面的研究。本文从材料元素组成的角度简单介绍了量子点的类型及其在LED、太阳能电池、生物医用以及重金属离子检测等领域的应用。 展开更多
关键词 量子点 分类 应用
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静电纺丝法合成S型异质结CoTiO_(3)/g-C_(3)N_(4)纳米纤维及其增强的可见光光催化活性研究
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作者 杨令坤 李宗军 +2 位作者 王鑫 李铃铃 陈哲 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第4期237-249,共13页
随着社会的高速发展,化石燃料的消耗量急剧上升,这不仅导致了能源的短缺,而且引发了二氧化碳(CO_(2))及其他有害气体的过量排放,造成环境污染.利用太阳能将CO_(2)光催化转化为碳基燃料是解决上述问题的一种有效途径.在众多半导体光催化... 随着社会的高速发展,化石燃料的消耗量急剧上升,这不仅导致了能源的短缺,而且引发了二氧化碳(CO_(2))及其他有害气体的过量排放,造成环境污染.利用太阳能将CO_(2)光催化转化为碳基燃料是解决上述问题的一种有效途径.在众多半导体光催化材料中,钙钛矿氧化物(CoTiO_(3))由于具有独特的电子和晶体结构以及较好的稳定性而备受关注.然而,由于单一半导体光催化剂中光生电子-空穴对的复合率较高,导致其催化还原CO_(2)的能力有限,制约了其在可见光催化反应中的实际应用.研究发现,构建异质结是提高半导体光催化还原CO_(2)效率的重要策略之一,因此寻找可与CoTiO_(3)能带结构很好匹配的半导体材料至关重要.近年来,有机聚合物g-C_(3)N_(4)因具有独特的层状结构、较好的热稳定性和化学稳定性,对可见光响应性能良好而受到人们的关注.本研究旨在构建g-C_(3)N_(4)与CoTiO_(3)的S型异质结,以优化体系中光生载流子分离效率,从而有效提升光催化性能.本文首先采用静电纺丝法制备出CoTiO_(3)纳米纤维,然后通过一步煅烧法构建CoTiO_(3)/g-C_(3)N_(4)S型异质结光催化剂.X射线衍射仪、傅里叶红外光谱仪、扫描电镜和透射电镜结果证实成功制得了CoTiO_(3)/g-C_(3)N_(4)复合光催化剂.在可见光照射下,测试了不同CoTiO_(3)质量百分含量(0.5%,1%,1.5%,2%和3%,命名为0.5%CTO/CN,1%CTO/CN,1.5%CTO/CN,2%CTO/CN和3%CTO/CN)的CoTiO_(3)/g-C_(3)N_(4)S型异质结光催化剂对CO_(2)的还原能力(反应时间为4 h).结果发现,2%CTO/CN催化剂显示出最高的光催化性能,其催化生成CO和CH4的产率分别为46.5和0.825 mol g^(-1) h^(-1),且生成CO的选择性为98.3%.同时,为了进一步验证光催化性能增强规律,作为补充实验,进行了盐酸四环素(TCH)、土霉素(OTC)和氧氟沙星(OFX)光催化降解实验.结果表明,2%CTO/CN表现出最高的光催化降解效率,2%CTO/CN在光催化CO_(2)还原和抗生素降解方面均表现出较好的催化性能,这归因于g-C_(3)N_(4)与CoTiO_(3)之间S型异质结的形成.此外,为了讨论光催化还原CO_(2)的选择性,采用原位红外和理论计算得到中间体的活化过程及其吉布斯自由能,并利用同位素标定实验进一步确认了光催化还原CO_(2)反应产物中碳源均来自于CO_(2)气氛.经过稳态荧光、时间分辨荧光、瞬态光电流响应和电化学阻抗图谱测试进一步验证表明,2%CTO/CN异质结的形成降低了光生电子-空穴对的复合率和界面电荷转移电阻,为电荷转移提供了更好的路径,从而提高了光催化性能.为了深入探究S型异质结的反应机理,通过原位X射线光电子能谱、原位电子顺磁共振和密度泛函理论计算研究了光照前后界面处电子流向.具体来说,在g-C_(3)N_(4)和CoTiO_(3)接触之前,g-C_(3)N_(4)的功函数小于CoTiO_(3),费米能级高于CoTiO_(3);当g-C_(3)N_(4)和CoTiO_(3)接触时,电子会从g-C_(3)N_(4)转移到CoTiO_(3),直到它们的费米能级达到平衡.此时,g-C_(3)N_(4)侧的界面电子耗尽,CoTiO_(3)侧的界面电子富集,使g-C_(3)N_(4)的带边向上弯曲带正电,而CoTiO_(3)的带边向下弯曲带负电.从而,在CTO/CN的界面处形成了内建电场(IEF),阻碍电子从g-C_(3)N_(4)向CoTiO_(3)的持续流动.光照时,光子同时被CoTiO_(3)和g-C_(3)N_(4)吸收,激发电子从价带跃迁至相应的导带.随后,在形成的IEF驱动下,CoTiO_(3)中的光生电子倾向于迁移到g-C_(3)N_(4),与g-C_(3)N_(4)中的光生空穴结合,使得体系中还原性和氧化性更强的电子和空穴得以保留,从而进一步提高光催化性能.综上,S型电荷转移途径不仅促进了光生载流子的分离,使得更多电子参与反应,而且同时保留了还原性和氧化性较强光生电子和空穴,因此,CTO/CN在光催化还原CO_(2)和降解抗生素方面表现出较好的性能.本文为基于g-C_(3)N_(4)的S型异质结材料在CO_(2)光还原和抗生素降解领域的应用提供参考. 展开更多
关键词 静电纺丝 S型异质结 g-C_(3)N_(4) 光催化降解 光催化还原CO_(2)
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Temporal and spatial evolution of global major grain trade patterns
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作者 Ziqi Yin Jiaxuan Hu +3 位作者 Jing Zhang Xiangyang Zhou lingling li Jianzhai Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1075-1086,共12页
The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain ... The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain trade from 1990 to 2020, focusing on network topology, centrality ranking, and community structure. There are three major findings. First, the global major grain trade network has expanded in scale, with a growing emphasis on diversification and balance. During the study period, the United States, Canada, China, and Brazil were the core nodes of the network. Grain-exporting countries were mainly situated in Asia, the Americas, and Europe, and importing countries in Asia, Africa, and Europe. Second, a significant increase in the number of high centrality countries with high export capacity occurred, benefiting from natural advantages such as fertile land and favorable climates. Third, the main global grain trade network is divided into four communities, with the Americas-Europe community being the largest and most widespread. The formation of the community pattern was influenced by geographic proximity, driven by the core exporting countries. Therefore, the world needs to enhance the existing trade model, promote the multi-polarization of the grain trade network, and establish a global vision for the future community. Countries and regions should participate actively in global grain trade security governance and institutional reform, expand trade links with other countries, and optimize import and export policies to reduce trade risks. 展开更多
关键词 grain trade pattern evolution complex network
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Modified Xiaoyao powder for postpartum depression:A systematic review and meta-analysis
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作者 Mengyuan Hu Xiaowen Zhang +7 位作者 Xuya Zhang Dan Cheng Yali Zhang Xinyu Zhang lingling li Xinjie li Xue li Yi Lu 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期120-130,共11页
Objective:To evaluate the effectiveness and safety of modified Xiaoyao powder for postpartum depression(PPD)by conducting a systematic review of randomized controlled trials(RCTs).Methods:The Chinese National Knowledg... Objective:To evaluate the effectiveness and safety of modified Xiaoyao powder for postpartum depression(PPD)by conducting a systematic review of randomized controlled trials(RCTs).Methods:The Chinese National Knowledge Infrastructure Databases(CNKI),the Chinese Scientific Journals Database(VIP),Wanfang,Google Scholar,the SinoMed,Embase,Cochrane Library,and PubMed databases were searched from their inception to April 25,2023.The Cochrane Risk of Bias tool was used to assess the quality of the trials.We applied the risk ratio to present dichotomous data and the mean difference to present continuous data.Data with similar characteristics were pooled for meta-analysis and heterogeneity was assessed using I2.Results:This review included 35 trials involving 2848 participants.The quality of the included studies was low(unclear randomization processes and insufficient reporting of blinding).Participants treated with modified Xiaoyao powder plus Western medicine showed lower Hamilton Depression Scale(HAMD)depression score than those who used Western medicine alone(mean difference=-2.15;95%confidence interval:-2.52 to 1.78;P<.00001),and higher effective rate(relative risk=1.19;95%confidence interval:1.15 to 1.24;P<.00001),When comparing modified Xiaoyao alone with Western medicine,the HAMD depression score remained low,however,the efficacy rate was higher in the modified Xiaoyao group.Regarding adverse events,the modified Xiaoyao group reported weight gain,nausea,and diarrhea,but no severe adverse events were reported.Conclusion:Modified Xiaoyao may help relieve depression in PPD when used alone or in combination with Western medicine,with minor side effects.Therefore,future high-quality,large-sample size RCTs are warranted. 展开更多
关键词 Postpartum depression Modified Xiaoyao Chinese medicine Systematic review META-ANALYSIS
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打造教师教学发展共同体,多校共上一堂课——“大学化学实验课程群虚拟教研室”教研活动初探及成效 被引量:2
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作者 朱平平 邵伟 +37 位作者 姚奇志 郑媛 李婉 李玲玲 张万群 查正根 关明 白希 李厚金 胡昱 原弘 李恺 胡文远 王爱玲 赵军龙 翟翠萍 秦川丽 范乃英 胡瑞祥 沈永雯 郝俊生 张越 赵发琼 张海波 龚成斌 夏茹 郝海刚 张兴文 孙兴文 高珍 范勇 郭栋才 曹田 罗时玮 李红春 胡万群 兰泉 吴红 《大学化学》 CAS 2023年第10期37-48,共12页
介绍“大学化学实验课程群虚拟教研室”在创新教研形态、加强教学研究、共建优质资源以及开展教师培训等方面开展的一系列工作及取得的初步实效。重点阐明了“多校共上一堂课,共享教学云资源”的示范教学直播课活动的教研形式以及教学... 介绍“大学化学实验课程群虚拟教研室”在创新教研形态、加强教学研究、共建优质资源以及开展教师培训等方面开展的一系列工作及取得的初步实效。重点阐明了“多校共上一堂课,共享教学云资源”的示范教学直播课活动的教研形式以及教学内容的选取原则。 展开更多
关键词 虚拟教研室 示范教学 虚实结合 线上线下混合式教学 诺贝尔奖成果
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Design of Passive Constant‑Force End‑Effector for Robotic Polishing of Optical Reflective Mirrors 被引量:3
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作者 Jian Zhang liangxiao Zhao +2 位作者 lingling li Fulei Ma Guimin Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第6期89-97,共9页
Polishing plays an indispensable role in optical processing,especially for large-aperture optical reflective mirrors with freeform surfaces.Robotic polishing requires effective control of the contact force between the... Polishing plays an indispensable role in optical processing,especially for large-aperture optical reflective mirrors with freeform surfaces.Robotic polishing requires effective control of the contact force between the robot and the mirror during processing.In order to maintain a constant contact force during polishing,traditional polishing robots rely on closed-loop control of air cylinders,whose performances heavily rely on high-fidelity force sensing and real-time control.This paper proposes to employ a compliant constant-force mechanism in the end-effector of a polishing robot to passively maintain a constant force between the robot and the mirror,thus eliminating the requirement for force sensing and closed-loop control.The compliant constant force mechanism utilizing the second bending mode of fixed-guided compliant beams is adopted and elaborated for the passive end-effector.An end-effector providing a constant contact force of 40 N is designed and prototyped.The polishing experiment shows that the passive constant-force end-effector provides stable contact force between the robot and the mirror with fluctuation within 3.43 N,and achieves RMS(Root Mean Square)lower thanλ/10(λ=632.8 nm)of the polished surface of the largeaperture optical reflective mirror.It is concluded that the constant-force compliant mechanism provides a low-cost and reliable solution for force control in robotic polishing. 展开更多
关键词 Robotic polishing Fixed-guided compliant beam Constant-force compliant mechanism Passive force control
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Cascaded dual-channel fiber SPR temperature sensor based on liquid and solid encapsulations 被引量:1
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作者 Yong Wei lingling li +4 位作者 Chunlan liu Jiangxi Hu Yudong Su Ping Wu Xiaoling Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期252-260,共9页
In order to control the working wavelength range of the fiber surface plasmon resonance(SPR)temperature sensor and realize the wavelength division multiplexing type multi-channel fiber SPR temperature sensor,by compre... In order to control the working wavelength range of the fiber surface plasmon resonance(SPR)temperature sensor and realize the wavelength division multiplexing type multi-channel fiber SPR temperature sensor,by comprehensively investigating the influence of liquids with different thermal-optical coefficients and solid packaging materials on the performance of fiber SPR temperature sensor,a dual-channel fiber SPR temperature sensor based on liquid-solid cascade encapsulation was designed and fabricated.The liquid temperature sensing stage encapsulated in capillary worked in 616.03 nm-639.05 nm band,the solid sensing stage coated with pouring sealant worked in 719.37 nm-825.27 nm band,and the two stages were cascaded to form a fiber dual-channel temperature sensor.The testing results indicated that when the temperature range was 35℃-95℃,the sensitivity of two-stage temperature detection was−0.384 nm/℃and−1.765 nm/℃respectively.The proposed fiber sensor has simple fabrication and excellent performance which can be widely used in various fields of dual-channel temperature measurement and temperature compensation. 展开更多
关键词 surface plasmon resonance(SPR) temperature sensor liquid-solid cascade dual channel
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Integrated network pharmacology and experimental verification to explore the mechanism of Sangqi Qingxuan formula against hypertensive vascular remodeling
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作者 lingling li Jiayun Wu +4 位作者 Ruiqi Yao Deshuang Yang Ying Chen Jin Zhang li Huang 《Journal of Traditional Chinese Medical Sciences》 CAS 2022年第3期277-288,共12页
Objective: To investigate the bioactive components of Sangqi Qingxuan formula(SQQX), predict the pharmacological targets, and explore the mechanism of hypertensive vascular remodeling(HVR).Methods: Network pharmacolog... Objective: To investigate the bioactive components of Sangqi Qingxuan formula(SQQX), predict the pharmacological targets, and explore the mechanism of hypertensive vascular remodeling(HVR).Methods: Network pharmacology was adopted to predict how SQQX acts in HVR. The effectiveness was assessed by blood pressure measurements and pathological morphology observation based on a spontaneously hypertensive rat model, while the mechanism of SQQX on HVR was validated by immunohistochemistry(IHC) and western blot(WB) according to the results of network pharmacology.Results: There were 130 bioactive components of SQQX and 231 drug targets predicted by the Traditional Chinese Medicine Systems Pharmacology Database. Subsequently, 181 common targets were identified for SQQX against HVR, with TP53, MAPK1, and AKT1 as the core targets. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses was employed to identify the top 20 enriched functions and the top 20 pathways(P <.01). Finally, the key role of the ERK/MAPK signaling pathway in HVR was determined. The in vivo results suggested that SQQX reduced systolic blood pressure and increased the ratio of thoracic aortic wall thickness to lumen diameter. Additionally, compared with the model group, SQQX increased the expression of smooth muscle 22 alpha(IHC: P <.001;WB:P <.05) and decreased the expression of osteopontin(IHC: P <.001;WB: P <.05), ERK1/2(IHC: P <.001;WB: ERK1 & ERK2, all P <.05), p-ERK1/2(IHC: P <.001;WB: ERK1 & ERK2, all P <.05), and the ratio of pERK1/2 to ERK1/2 protein(IHC: P <.001).Conclusions: SQQX, which has multiple bioactive ingredients and potential targets, is an effective treatment for HVR. The mechanism of antihypertensive and vascular protection may be related to the inhibition of phenotypic transformation of vascular smooth muscle cells and the ERK/MAPK signaling pathway. 展开更多
关键词 Sangqi Qingxuan formula Network pharmacology Hypertensive vascular remodeling Action mechanism Experimental verification Spontaneously hypertensive rats Phenotypic transformation ERK/MAPK pathway
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Study on Expected Mature Age of Individual Saliz matsudana
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作者 lingling li Keqin li +3 位作者 Jing ZHANG Dequan ZHANG Zhijun YANG Hongbo QIAO 《Agricultural Biotechnology》 CAS 2019年第3期150-152,共3页
Based on the study of parse wood materials,the fitting empirical equation of tree growth was obtained,a function with tree growth as a variable and time as an independent variable.Through mathematical operations such ... Based on the study of parse wood materials,the fitting empirical equation of tree growth was obtained,a function with tree growth as a variable and time as an independent variable.Through mathematical operations such as function derivation,the mature age of tree growth was obtained,and the obtained expected mature age of Saliz matsudana was 21a.And the application,research directions and precautions of the mature ages were proposed. 展开更多
关键词 MATURE age Empirical EQUATION PARSE WOOD
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Fiber cladding dual channel surface plasmon resonance sensor based on S-type fiber 被引量:1
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作者 魏勇 赵晓玲 +6 位作者 刘春兰 王锐 蒋天赐 李玲玲 石晨 刘纯彪 竺栋 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期187-195,共9页
Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an ... Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an S-shaped structure on the fiber to couple the light in the fiber core to the cladding.In this paper,the effects of fiber parameters on the performance of the sensor were studied by simulation and experiment.Based on the conclusion that the smaller the core diameter is,the closer the working band of the SPR resonance is to long wavelengths,and that the geometric characteristics mean that a multimode fiber can receive the fiber cladding light from a small core diameter few-mode fiber,a dual channel SPR sensor with a double S-type fiber cascade was proposed.In the refractive index detection range of 1.333–1.385refractive index units(RIU),the resonant working band of channel I is 627.66 nm–759.78 nm,with an average sensitivity of 2540.77 nm/RIU,and the resonant working band of channel II is 518.24 nm–658.2 nm,with an average sensitivity of2691.54 nm/RIU.The processing method for the S-type fiber cladding SPR sensor is simple,effectively solving the problem of this type of SPR sensor structure and the difficult realization of a dual channel.The sensor is expected to be used in the fields of medical treatment and biological analysis. 展开更多
关键词 surface plasmon resonance(SPR) S-type structure dual channel cladding fiber SPR sensor
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Deformation and stability of the seawall,considering the strength uncertainty of cement mixing piles
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作者 Yuansheng YU lingling li +2 位作者 Xiangmiao KONG Chengyuan li Zhen GUO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2024年第6期483-501,共19页
The cement mixing (CM) pile is a common method of improving soft offshore ground. The strength growth of CM piles under complex conditions is affected by many factors, especially the cement and moisture contents, and ... The cement mixing (CM) pile is a common method of improving soft offshore ground. The strength growth of CM piles under complex conditions is affected by many factors, especially the cement and moisture contents, and shows significant uncertainty. To investigate the stochasticity of the early strength of CM piles and its impact on the displacement and stability of a seawall, a series of laboratory tests and numerical analyses were carried out in this study. Vane shear tests were conducted on the cement-solidified soil to determine the relationships between the undrained shear strength s_(u) of the cement soil curing in the seawater and the cement content a_(c), as well as the in situ soil moisture content w. It can be inferred that the 24 h undrained shear strength follows a normal distribution. A numerical model considering the random CM pile strength was established to investigate the deformation of the seawall. Due to the uncertainty of CM pile strength, the displacement of the seawall demonstrates a certain discreteness. The decrease of the mean undrained shear strength of CM piles causes a corresponding increase in the average displacement of the seawall. When the mean strength of CM piles is lower than a certain threshold, there is a risk of instability. Furthermore, the heterogeneity of the strength within an individual CM pile also has an impact on seawall displacement. Attention should be paid to the uncertainty of CM pile strength to control displacement and stability. 展开更多
关键词 Construction uncertainty Cement mixing(CM)pile Strength of cement soil Seawall stability Random finite element method(RFEM) Monte Carlo simulation(MCS)
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“互联网+”背景下大学化学实验的在线辅助教学模式创新及成效探索 被引量:29
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作者 朱平平 冯红艳 +17 位作者 邵伟 郑媛 李玲玲 李婉 方思敏 张万群 李维维 盛翔 胡万群 高明丽 兰泉 蒋俊 金谷 查正根 刘卫 黄微 刘红瑜 刘光明 《大学化学》 CAS 2020年第5期278-282,共5页
2020年春季学期新冠肺炎疫情防控期间,中国科学技术大学化学实验教学中心充分考虑各实验课程特点,及时调整了教学计划,形成切实可行的“一课一策”在线教学方案,利用前期建设的在线开放课程、虚拟仿真实验教学项目和其他优质教学资源开... 2020年春季学期新冠肺炎疫情防控期间,中国科学技术大学化学实验教学中心充分考虑各实验课程特点,及时调整了教学计划,形成切实可行的“一课一策”在线教学方案,利用前期建设的在线开放课程、虚拟仿真实验教学项目和其他优质教学资源开展在线辅助教学,取得初步成效。 展开更多
关键词 大学化学实验 在线教学 线上“金课” 大规模在线开放课程 虚拟仿真实验教学项目
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创新教学方法,助力本科生科研创新能力培养--“扶-牵-引-放”四步教学法 被引量:12
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作者 姚奇志 金谷 +3 位作者 朱平平 李玲玲 李娇 刘红瑜 《大学化学》 CAS 2021年第7期128-132,共5页
人才培养是高校最主要的职责。本科阶段是科研创新型人才培养的关键时期,而实验教学是提高本科生科研创新能力、培养应用型人才的重要环节。本文系统介绍了在"基础型-综合型-探究型-设计型"多层次、递进式分析化学实验教学过... 人才培养是高校最主要的职责。本科阶段是科研创新型人才培养的关键时期,而实验教学是提高本科生科研创新能力、培养应用型人才的重要环节。本文系统介绍了在"基础型-综合型-探究型-设计型"多层次、递进式分析化学实验教学过程中,如何运用"扶-牵-引-放"四步教学法,循序渐进地培养学生发现、分析问题和解决问题的综合实验能力,进而培养学生求异思维和创新能力,实现了知识和技能传授与科研创新素质培养并重的教学目的。 展开更多
关键词 教学方法 实验教学 本科生 科研能力 创新意识
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