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Unconfined compressive strength and failure behaviour of completely weathered granite from a fault zone

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Journal of Mountain Science 2024年第6期21卷 2140-2158页

作者： DU Shaohua MA Jinyin MA liyao ZHAO Yaqian School of Civil Engineering and Architecture Henan University of Science and TechnologyLuoyang 471023China School of Resources and Safety Engineering Central South UniversityChangsha 410083China China Railway 18th Bureau Group Co. LtdTianjin 300222 China China General Nuclear Power Corporation Shenzhen 518031China

Understanding the strength characteristics and deformation behaviour of the tunnel surrounding rock in a fault zone is significant for tunnel stability *** this study,a series of unconfined compression tests were conducted to investigate the mechanical characteristics and failure behaviour of completely weathered granite(CWG)from a fault zone,considering with height-diameter(h/d)ratio,dry densities(ρd)and moisture contents(ω).Based on the experimental results,a regression mathematical model of unconfined compressive strength(UCS)for CWG was developed using the Multiple Nonlinear Regression method(MNLR).The research results indicated that the UCS of the specimen with a h/d ratio of 0.6 decreased with the increase ofω.When the h/d ratio increased to 1.0,the UCS increasedωwith up to 10.5%and then ***ρd is conducive to the improvement of the UCS at anyω.The deformation and rupture process as well as final failure modes of the specimen are controlled by h/d ratio,ρd andω,and the h/d ratio is the dominant factor affecting the final failure mode,followed byωandρ*** specimens with different h/d ratio exhibited completely different fracture mode,i.e.,typical splitting failure(h/d=0.6)and shear failure(h/d=1.0).By comparing the experimental results,this regression model for predicting UCS is accurate and reliable,and the h/d ratio is the dominant factor affecting the UCS of CWG,followed byρd and thenω.These findings provide important references for maintenance of the tunnel crossing other fault fractured zones,especially at low confining pressure or unconfined condition.

关键词： Fault fracture zone Completely weathered granite(CWG) Unconfined compression strength(UCS) Multiple nonlinear regression model

Management of triplet excitons transition:fine regulation of Förster and dexter energy transfer simultaneously

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Light(Science & Applications) 2024年第2期13卷 302-315页

作者： Jiaqiang Wang Yujie Yang Xinnan Sun Xiaoning Li liyao Zhang Zhen Li Institute of Molecular Aggregation Science Tianjin UniversityTianjin300072China School of Life Sciences Tianjin UniversityTianjin300072China Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhan430072China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430072China Joint School of National University of Singapore Tianjin UniversityInternational Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Understanding and management of triplet excitons transition in the same molecule remain a great ***,for the first time,by host engineering,manageable transitions of triplet excitons in a naphthalimide derivative NDOH were achieved,and monitored through the intensity ratio(ITADF/IRTP)between thermally activated delayed fluorescence(TADF)and room-temperature phosphorescence(RTP).Energy differences between lowest triplet excited states of host and guest were changed from 0.03 to 0.17 eV,and ITADF/IRTP of NDOH decreased by 2.0 times,thus red shifting the afterglow *** was proposed that shorter conjugation length led to larger band gaps of host materials,thus contributing to efficient Dexter and inefficient Förster energy ***,no transition to singlet state and only strongest RTP with quantum yield of 13.9%could be observed,when PBNC with loosest stacking and largest band gap acted as *** work provides novel insight for the management and prediction of triplet exciton transitions and the development of smart afterglow materials.

关键词： materials transition transitions

Identification of key genes regulating the synthesis of quercetin derivatives in Rosa roxburghii through integrated transcriptomics and metabolomics

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Journal of Integrative Agriculture 2024年第3期23卷 876-887页

作者： liyao Su Min Wu Tian Zhang Yan Zhong Zongming(Max) Cheng State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjing210095China

Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five different stages of R. roxburghii fruit development. Flavonoids and the genes related to their biosynthesis were found to undergo significant changes in abundance across different developmental stages, and numerous quercetin derivatives were identified. We found three gene expression modules that were significantly associated with the abundances of the different flavonoids in R. roxburghii and identified three structural UDP-glycosyltransferase genes directly involved in the synthesis of quercetin derivatives within these modules. In addition, we found that RrBEH4, RrLBD1 and RrPIF8could significantly increase the expression of downstream quercetin derivative biosynthesis genes. Taken together,these results provide new insights into the metabolism of flavonoids and the accumulation of quercetin derivatives in R. roxburghii.

关键词： Rosa roxburghii quercetin derivatives weighted gene co-expression network analysis transcription factor transcriptome metabolome

Current Status and Perspectives of Dual-Atom Catalysts Towards Sustainable Energy Utilization

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Nano-Micro Letters 2024年第7期16卷 402-440页

作者： Yizhe Li Yajie Li Hao Sun liyao Gao Xiangrong Jin Yaping Li Zhi LV Lijun Xu Wen Liu Xiaoming Sun State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science EngineeringCollege of ChemistryBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China Xinjiang Coal Mine Mechanical and Electrical Engineering Technology Research Center Xinjiang Institute of EngineeringUrumqi 830023Xinjiang Uygur Autonomous RegionPeople’s Republic of China

The exploration of sustainable energy utilization requires the imple-mentation of advanced electrochemical devices for efficient energy conversion and storage,which are enabled by the usage of cost-effective,high-performance ***,heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of *** to conventional cata-lysts,atomically dispersed metal atoms in carbon-based catalysts have more unsatu-rated coordination sites,quantum size effect,and strong metal-support interactions,resulting in exceptional catalytic *** these,dual-atomic catalysts(DACs)have attracted extensive attention due to the additional synergistic effect between two adja-cent metal *** have the advantages of full active site exposure,high selectiv-ity,theoretical 100%atom utilization,and the ability to break the scaling relationship of adsorption free energy on active *** this review,we summarize recent research advancement of DACs,which includes(1)the comprehensive understanding of the synergy between atomic pairs;(2.the synthesis of DACs;(3)characterization meth-ods,especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy;and(4)electrochemical energy-related *** last part focuses on great potential for the electrochemical catalysis of energy-related small molecules,such as oxygen reduction reaction,CO_(2. reduction reaction,hydrogen evolution reaction,and N_(2. reduction *** future research challenges and opportunities are also raised in prospective section.

关键词： Dual-atom catalysts Synergetic effect Electrocatalysis Oxygen reduction reaction CO_(2.reduction reaction Hydrogen evolution reaction N2.reduction reaction

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直升机超临界尾轴限幅减振器安装位置研究

航空动力学报 2024年第6期39卷 86-96页

作者：宋立瑶王旦曹鹏陈柏朱如鹏南京航空航天大学直升机传动技术国家级重点实验室南京210016 中国航发湖南动力机械研究所直升机传动技术国家级重点实验室湖南株洲412002

为了使限幅减振器对传动轴跨1阶及2.临界转速均起到较好的减振作用,研究了限幅减振器安装位置对传动轴与限幅减振器系统非线性动力学的影响。首先基于Timoshenko梁和非线性碰摩理论建立了传动轴与限幅减振器系统的非线性有限元动力学模... 详细信息

为了使限幅减振器对传动轴跨1阶及2.临界转速均起到较好的减振作用,研究了限幅减振器安装位置对传动轴与限幅减振器系统非线性动力学的影响。首先基于Timoshenko梁和非线性碰摩理论建立了传动轴与限幅减振器系统的非线性有限元动力学模型,通过数值计算得到了系统响应。对传动轴典型跨临界过程及安装位置对减振效果的影响进行了分析。结果表明:一个典型的传动轴跨临界过程可以分为4个阶段,分别为无碰摩、拟周期碰摩、同频全周碰摩,最后回到无碰摩阶段。将减振器安装在中间节点只能有效抑制传动轴跨1阶临界转速的振动,而安装在1/4节点及3/8节点处能同时减弱跨1阶及2.临界转速的振动,但安装在3/8节点处有可能使传动轴无法正常工作。

关键词：限幅减振器超临界尾轴位置优化碰摩干摩擦

一咏三叹,由景至境——《诗经·国风》中自然景观展现特征及先民审美模式研究

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西部人居环境学刊 2024年第3期39卷 103-108页

作者：谷光灿王丽瑶重庆大学建筑城规学院

《诗经》是我国诗歌史上举足轻重的存在,《国风》正是《诗经》的精华。在《国风》诗中,大量的诗歌涉及到了自然景观,而对于《诗经》的研究大多集中在文史哲领域,立足于风景园林学的相关研究较为匮乏,作为描写风景的最早诗篇尚未被研究... 详细信息

《诗经》是我国诗歌史上举足轻重的存在,《国风》正是《诗经》的精华。在《国风》诗中,大量的诗歌涉及到了自然景观,而对于《诗经》的研究大多集中在文史哲领域,立足于风景园林学的相关研究较为匮乏,作为描写风景的最早诗篇尚未被研究颇为遗憾。因此将其作为研究重点,首先对《国风》中的自然景观要素进行提取、分类,分析其特点,得出其层次性和分时性的展现规律,以此为基础总结出先民既存型、演化型和类比型三种审美模式,即对中国人原生情感中的自然景观的感知方式和审美模式的溯源。寻找中国人对自然景观情感的原始表达,以及遗传意义,以期为现今的风景遗产保护与景观设计提供参考与启示。

关键词：《诗经》国风人居环境自然景观审美模式

基于时空轨迹聚类算法的城市休闲地动态交互特征研究

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旅游学刊 2024年第4期39卷 28-39页

作者：郭鑫郑伟民黄利瑶厦门大学管理学院福建厦门361005

城市休闲地交互现象的研究有助于理解城市休闲活动的互动关系和复杂的城市休闲系统。相关研究多关注休闲要素的静态空间分布格局,缺少对休闲地动态交互作用的探讨。为此,文章利用出租车轨迹数据,从移动性视角提出城市休闲地空间和功能... 详细信息

城市休闲地交互现象的研究有助于理解城市休闲活动的互动关系和复杂的城市休闲系统。相关研究多关注休闲要素的静态空间分布格局,缺少对休闲地动态交互作用的探讨。为此,文章利用出租车轨迹数据,从移动性视角提出城市休闲地空间和功能动态交互特征的研究框架。首先赋予出租车轨迹点语义信息,其次构建相似轨迹网络,然后运用Louvain社区发现算法对休闲轨迹聚类,最后基于聚类结果及其语义信息,分析城市休闲空间和休闲功能的动态交互特征。研究结果如下:1)城市休闲地具有较强的空间集聚效应;2.凌晨低强度收缩型交互模式以短距离交互为主,上午低强度扩张型和下午高强度扩张型交互模式的中程距离交互突出,夜晚高强度收缩型交互模式的短距离交互分布扩大;3)在各空间交互模式中,餐饮与购物休闲功能两者之间以及与其他休闲功能交互显著,文娱休闲在模式一中的交互能力最强,游览休闲在模式二、模式三和模式四的长距离交互中与其他休闲功能交互作用显著,除模式二外,长距离对住宿休闲的交互力影响较大,而康养休闲的交互随模式和距离变化呈稳定特征。研究对城市休闲空间优化布局、休闲功能规划以及促进城市休闲产业可持续发展具有指导意义。

关键词：城市休闲空间城市休闲功能动态交互特征移动性时空轨迹聚类

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黎族“龙被”艺术之当代价值与活态传承

印染 2024年第3期50卷 98-101页

作者：马立尧冯莉颖海南大学国际传播与艺术学院海南海口570228 马来西亚理科大学艺术学院马来西亚槟城100032 海南科技职业大学教务处海南海口571126

黎族龙被是黎族织锦艺术的珍品,其传统纺染织绣技艺已被列入世界非物质文化遗产。黎族龙被的纹样特征、设计规律、文化融合等极具考究价值。从黎族龙被保护传承的现状入手,深入分析黎族龙被的传承与当代生活相交融的特征,充分挖掘其文... 详细信息

黎族龙被是黎族织锦艺术的珍品,其传统纺染织绣技艺已被列入世界非物质文化遗产。黎族龙被的纹样特征、设计规律、文化融合等极具考究价值。从黎族龙被保护传承的现状入手,深入分析黎族龙被的传承与当代生活相交融的特征,充分挖掘其文化价值,科技赋能构建新的传承和发展标准,集聚各界优势,构建黎族龙被活态传承路径,为黎族龙被知识体系的构建与传承创新提供必要的理论支撑。

关键词：龙被艺术黎族织锦纺织非遗活态传承

盾构隧道侧穿引发砌体建筑物变形损伤实例研究

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现代隧道技术 2024年第3期61卷 119-130页

作者：屈浩张波张振义张丽瑶内蒙古科技大学土木工程学院包头014010 北京城建设计发展集团股份有限公司北京100034 呼和浩特城市交通投资建设集团有限公司呼和浩特010090 福州大学土木工程学院福州350108

现有关于盾构隧道侧穿砌体建筑物的研究,大多只针对砌体建筑物沉降和整体倾斜指标进行分析,当砌体建筑物发生不均匀沉降时,容易产生裂缝,仅从这两项指标不能分析建筑物开裂损伤情况。在使用常规本构模型进行盾构隧道侧穿数值模拟计算时... 详细信息

现有关于盾构隧道侧穿砌体建筑物的研究,大多只针对砌体建筑物沉降和整体倾斜指标进行分析,当砌体建筑物发生不均匀沉降时,容易产生裂缝,仅从这两项指标不能分析建筑物开裂损伤情况。在使用常规本构模型进行盾构隧道侧穿数值模拟计算时,既不能体现砌体建筑物独特的结构,也不能反映出建筑物上发生的开裂和应变情况。基于此,以呼和浩特地铁1号线盾构隧道侧穿玛拉沁饭店为工程背景,在数值模拟中使用节理砌体本构模型进行有限元计算,并结合工程实测数据对盾构侧穿后建筑物不均匀沉降和应变情况进行分析。结果表明:(1)盾构隧道侧穿砌体建筑物后,砌体建筑物的开裂区域是从下往上发展的,拉伸应变较大的区域主要集中在建筑物最底部,大部分拉伸应变区域与门洞位置相关联;(2.砌体建筑物不均匀沉降区域集中在建筑物的门窗洞口位置,不均匀沉降较大的区域与应变较大的区域相对应,该区域更容易发生开裂;(3)随着砌筑砂浆黏聚力的增加,砌体建筑物发生的应变和不均匀沉降逐渐减小,砌体建筑物易开裂区域逐渐减少。

关键词：盾构侧穿砌体建筑物节理砌体模型拉伸应变小应变硬化模型