检索结果-南通市图书馆

Fluid Dynamics & Materials Processing 2022年第1期18卷 131-144页

作者： Zhenggang Zhan Han Chen Yanyi Zhang ruilin cheng Gang Deng PowerChina Guiyang Engineering Co. Ltd.Guiyang550081China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China Key Laboratory of Construction and Safety of Hydraulic Engineering of Ministry of Water Resources China Institute of Water Resources and Hydropower ResearchBeijing100038China

The factors influencing the permeability coefficient of gravelly soils used for the development of embankment dams(core wall)are analyzed.Such factors include(but are not limited to)soil size,anisotropy,density and boundary effects.A review of the literature is conducted and new directions of research are proposed.In such a framework,it is shown that gravelly soil with controlled density and vertical stress should be used to optimize the measurement of the vertical and horizontal permeability coefficients,respectively.

关键词： Wide-grading gravelly soil core wall materials permeability coefficient test method

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

高心墙堆石坝材料本构模型计算的适用性研究

中南大学学报（自然科学版） 2024年第1期55卷 219-229页

作者：程瑞林汪泾周范钦煜湛正刚周伟马刚武汉大学水资源工程与调度全国重点实验室湖北武汉430072 中国电建集团贵阳勘测设计研究院有限公司贵州贵阳550081 武汉大学水工程科学研究院湖北武汉430072

为研究不同材料本构模型对高心墙堆石坝应力、变形计算的适用性,以RM 300 m级高心墙堆石坝堆石料的室内试验成果为基础,分别对邓肯E-B模型、沈珠江双屈服面模型及MPZG模型进行材料本构验证和坝体有限元分析。研究结果表明:3种模型均能... 详细信息

为研究不同材料本构模型对高心墙堆石坝应力、变形计算的适用性,以RM 300 m级高心墙堆石坝堆石料的室内试验成果为基础,分别对邓肯E-B模型、沈珠江双屈服面模型及MPZG模型进行材料本构验证和坝体有限元分析。研究结果表明:3种模型均能较好地表现堆石料三轴路径下的应力响应,而邓肯EB模型在低围压下体积响应表现效果欠佳;3种模型计算的坝体应力、变形分布均符合一般规律,应力相近,但变形计算中邓肯E-B模型得到的沉降与顺河向位移均较大;在高心墙堆石坝建设初期,可采用邓肯E-B模型进行早期分析,后期宜采用沈珠江双屈服面模型、MPZG模型等进行决策评价。

关键词：应力变形本构模型心墙堆石坝有限元分析广义塑性模型

Single-Atom Catalysts for Electrochemical Hydrogen Evolution Reaction: Recent Advances and Future Perspectives

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2020年第2期12卷 73-101页

作者： Zonghua Pu Ibrahim Saana Amiinu ruilin cheng Pengyan Wang chengtian Zhang Shichun Mu Weiyue Zhao Fengmei Su Gaixia Zhang Shijun Liao Shuhui Sun Institut National de la Recherche Scientifique-Énergie Matériaux et Télécommunications VarennesQC J3X 1S2Canada State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People’s Republic of China The Key Laboratory of Fuel Cell Technology of Guangdong Province The Key Laboratory of New Energy Technology of Guangdong UniversitiesSchool of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510641People’s Republic of China Key Laboratory of Materials Processing and Mold Ministry of EducationZhengzhou UniversityZhengzhou 450002People’s Republic of China

Hydrogen,a renewable and outstanding energy carrier with zero carbon dioxide emission,is regarded as the best alternative to fossil fuels.The most preferred route to large-scale production of hydrogen is by water electrolysis from the intermittent sources(e.g.,wind,solar,hydro,and tidal energy).However,the efficiency of water electrolysis is very much dependent on the activity of electrocatalysts.Thus,designing high-effective,stable,and cheap materials for hydrogen evolution reaction(HER)could have a substantial impact on renewable energy technologies.Recently,single-atom catalysts(SACs)have emerged as a new frontier in catalysis science,because SACs have maximum atom-utilization efficiency and excellent catalytic reaction activity.Various synthesis methods and analytical techniques have been adopted to prepare and characterize these SACs.In this review,we discuss recent progress on SACs synthesis,characterization methods,and their catalytic applications.Particularly,we highlight their unique electrochemical characteristics toward HER.Finally,the current key challenges in SACs for HER are pointed out and some potential directions are proposed as well.

关键词： Single-atom catalysts Nanomaterials Electrocatalyst Hydrogen evolution reaction Electrochemical energy conversion

在线全文

学校读者我要写书评

暂无评论

RS堆积体滑坡涌浪特征数值模拟研究

三峡大学学报（自然科学版） 2024年第3期46卷 8-14页

作者：湛正刚程瑞林张合作马行生胡大儒王照英王环玲中国电建集团贵阳勘测设计研究院有限公司贵阳550081 河海大学岩土工程科学研究所南京210098 华能澜沧江水电股份有限公司昆明650021

库区滑坡涌浪是滑坡产生的次生灾害,严重威胁库区工程安全及大坝稳定运行.澜沧江RM水电站RS堆积体方量巨大,且位于近坝区,开展RMRS堆积体滑坡涌浪特征研究对大坝工程安全设计和施工至关重要.本文建立RS堆积体滑坡涌浪远近场计算模型,基... 详细信息

库区滑坡涌浪是滑坡产生的次生灾害,严重威胁库区工程安全及大坝稳定运行.澜沧江RM水电站RS堆积体方量巨大,且位于近坝区,开展RMRS堆积体滑坡涌浪特征研究对大坝工程安全设计和施工至关重要.本文建立RS堆积体滑坡涌浪远近场计算模型,基于光滑粒子流体动力学方法及浅水方程,研究RM工程正常蓄水位2895m情况下RS堆积体滑动产生的涌浪特征,并与经验公式法进行对比.研究表明:分析所采用的数值模拟方法在研究滑坡涌浪中具有优势,该方法可准确模拟滑坡体入水产生的非线性流固耦合过程,准确捕捉涌浪传播过程中受到复杂地形影响以及爬升过程中的地形相关性.研究结果可为评估RMRS堆积体滑坡涌浪对工程安全的影响提供参考.

关键词： RS堆积体滑坡涌浪光滑粒子流体动力学涌浪传播大坝爬高

A historical review of hybrid rice breeding

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2024年第3期66卷 532-545页

作者： Xiaoming Zheng Fei Wei cheng cheng Qian Qian State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Yazhouwan National Laboratory Sanya City 572024China

The development of germplasm resources and advances in breeding methods have led to steady increases in yield and quality of rice (Oryza sativa L.). Three milestones in the recent history of rice breeding have contributed to these increases: dwarf rice breeding, hybrid rice breeding, and super rice breeding. On the 50th anniversary of the success of three-line hybrid rice,we highlight important scientific discoveries in rice breeding that were made by Chinese scientists and summarize the broader history of the field. We discuss the strategies that could be used in the future to optimize rice breeding further in the hope that China will continue to play a leading role in international rice breeding.

关键词： Chinese experience dwarf breeding hybrid rice breeding super rice breeding

Complex-frequency waves:beat loss and win sensitivity

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第2期13卷 181-183页

作者： Qingqing cheng Tao L School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Respiratory Diseases and Critical Medicine Quzhou Hospital Affiliated to Wenzhou Medical UniversityQuzhou324000China National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesNanjing UniversityNanjing210093China

Recent experiments have demonstrated that synthesized complex-frequency waves can impart a virtual gain to molecule sensing systems,which can effectively restore information lost due to intrinsic molecular damping.The enhancement notably amplifies the signal of trace molecular vibrational fingerprints,thereby substantially improving the upper limit of sensitivity.

关键词： thereby Complex limit

Triple reverse order law for the Drazin inverse

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

Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： WANG Hua ZHONG cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation relations.Moreover,the Drazin invertibility of sum is also obtained for two bounded linea... 详细信息

关键词： Drazin inverse reverse order law space decomposition

Bioinspired 3D flexible devices and functional systems

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第3期11卷 271-295页

作者： Xu cheng Zhangming Shen Yihui Zhang Applied Mechanics Laboratory Department of Engineering Mechanics Tsinghua University Laboratory of Flexible Electronics Technology Tsinghua University

Flexible devices and functional systems with elaborated three-dimensional(3D) architectures can endow better mechanical/electrical performances, more design freedom, and unique functionalities, when compared to their two-dimensional(2D) counterparts. Such 3D flexible devices/systems are rapidly evolving in three primary directions, including the miniaturization, the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous integration.Intractable challenges exist in this emerging research area, such as relatively poor controllability in the locomotion of soft robotic systems, mismatch of bioelectronic interfaces, and signal coupling in multi-parameter sensing. By virtue of long-time–optimized materials, structures and processes, natural organisms provide rich sources of inspiration to address these challenges, enabling the design and manufacture of many bioinspired 3D flexible devices/systems. In this Review, we focus on bioinspired 3D flexible devices and functional systems, and summarize their representative design concepts, manufacturing methods, principles of structure-function relationship and broad-ranging applications. Discussions on existing challenges, potential solutions and future opportunities are also provided to usher in further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes,enhanced mechanical/electrical performances, and high-level physical/artificial intelligence.

关键词： bioinspired designs biomimetic 3D structures 3D flexible electronics 3D functional systems direct 3D manufacture 2D-to-3D assembly

Nutrient transport following water transfer through the world's largest water diversion channel

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第1期135卷 703-714页

作者： Yuanhui cheng Hong Zhang Wei Yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051China University of Chinese Academy of Sciences Beijing 100049China

Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large,interbasin scheme.However,the distribution and transport of nutrients along the channel were poorly understood.Based on a time-series dataset as well as mass balance and material flow analysis methods,the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this study.The results indicate that the nutrient concentrations varied considerably with time,but there was no significant difference among the 30 stations of the main channel.Seasonal temperature difference was the major factor in the large fluctuations of water quality indicators over time.The nutrient loadings varied with the water volume outputs from the main channel to the waterreceiving cities.Atmospheric deposition was an important source of nutrients in the main channel,accounting for 9.13%,20.6%,and 0.635%of the nitrogen,phosphorus,and sulfur input from the Danjiangkou Reservoir,respectively.In 2021,a net accumulation of 988 tons of N,29 tons of P,and 2,540 tons of S,respectively,were present in the main channel.The increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main channel.Our study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment,assisting authorities on the project to develop effective water conservation strategies.

关键词： Nutrient transport Spatiotemporal patterns The Middle Route The South-to-North Diversion Project Hydro-ecological effects Water-receiving cities

Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng Wang Xiaoqi Wang Shuiyuan cheng Jiaxian Zhu Xinyu Zhang Long cheng Kai Wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in China.We estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research results.Then,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was analyzed.Moreover,priority control routes for VOC emission sources were proposed for different periods.Anthropogenic VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main contributors.Industrial protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and SOAFP.Priority in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in China.In addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route