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Improving the WRF/urban modeling system in China by developing a national urban dataset

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Geoscience Frontiers 2022年第4期13卷 75-88页

作者： Huidong Li fenghui yuan Lidu Shen Yage Liu Zhonghua Zheng Xu Zhou CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Lamont-Doherty Earth Observatory of Columbia University PalisadesNY 10964United States National Tibetan Plateau Data Centre Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Accurate modeling of urban climate is essential to predict potential environmental risks in *** datasets,such as urban land use and urban canopy parameters(UCPs),are key input data for urban climate models and largely affect their ***,access to reliable urban datasets is a challenge,especially in fast urbanizing *** this study,we developed a high-resolution national urban dataset in China(NUDC)for the WRF/urban modeling system and evaluated its effect on urban climate ***,an optimization method based on building morphology was proposed to classify urban land use *** key UCPs,including building height and width,street width,surface imperviousness,and anthropogenic heat flux,were calculated for both single-layer Urban Canopy Model(UCM)and multiple-layer Building Energy Parameterization(BEP).The results show that the derived morphological-based urban land use classification could better reflect the urban characteristics,compared to the socioeconomic-function-based *** UCPs varied largely in spatial within and across the *** integration of the developed urban land use and UCPs datasets significantly improved the representation of urban canopy characteristics,contributing to a more accurate modeling of near-surface air temperature,humidity,and wind in urban *** UCM performed better in the modeling of air temperature and humidity,while the BEP performed better in the modeling of wind *** newly developed NUDC can advance the study of urban climate and improve the prediction of potential urban environmental risks in China.

关键词： Urban climate modeling UCM BEP Urban land use Urban canopy parameter Chinese cities

鄱阳湖南矶湿地蜘蛛及其昆虫猎物多样性季节变化与群落功能分析

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中国科技论文在线精品论文

中国科技论文在线精品论文 2024年第1期17卷 10-24页

作者：陈连水袁凤辉饶军张针针周雅珍东华理工大学化学生物与材料科学学院南昌330013

研究旨在探讨蜘蛛及其昆虫猎物对湿地生态系统结构的稳定性及能量与物质循环的指示作用,为鄱阳湖南矶湿地国家级自然保护区生物多样性的保护与利用提供参考。结合景观生态原理,采用群落样点设置与观察、关联标本采集与鉴定等生态定量调... 详细信息

研究旨在探讨蜘蛛及其昆虫猎物对湿地生态系统结构的稳定性及能量与物质循环的指示作用,为鄱阳湖南矶湿地国家级自然保护区生物多样性的保护与利用提供参考。结合景观生态原理,采用群落样点设置与观察、关联标本采集与鉴定等生态定量调查及多样性分析方法。本次调查共采得蜘蛛16科50属73种,得到的结论如下:1)群落结构与功能分析表明,南矶灌丛为蜘蛛繁育发生提供了庇护所,充当蛛库;南矶草甸是蜘蛛捕食行为实战与演化的平台,南矶林地是各类蜘蛛限时汇聚、适时飞航的踏板;在春夏季,南矶草甸中的水生或地栖昆虫是蜘蛛的主要偏好猎物或潜在捕食对象,进入秋冬季,南矶灌丛或林地成为不常见昆虫的汇集地;它们分别主导着南矶蜘蛛及其昆虫猎物群落丰富度、优势度、多样性和均匀度的高低起伏。2)聚类分析表明,南矶湿地各蜘蛛群落间的交流频率与连续性程度受地域异质性和空间距离的限制较为明显,群落类型的内聚作用和发散功能稳定;各昆虫猎物群落间的交流频率与连续性程度受时域同质化和季节物候的影响较为明显,群落类型的边缘差异与斑块功能稳定。3)相关分析表明,蜘蛛及其昆虫猎物群落在春夏季、秋冬季和总体上的各项多样性指数互有关联,且部分时空指数存在交错相关现象,地域与季节性温湿度等物候条件的变化是其主要驱动力。蜘蛛和昆虫是食物链中两个重要的中间环节,它们共同维持着南矶湿地生态系统的运转和平衡。

关键词：动物学南矶湿地蜘蛛昆虫猎物多样性季节变化群落功能

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金属纤维纺织品在工业上的应用与展望

产业用纺织品 2024年第1期42卷 23-30页

作者：孙鹏陈文豆董锬姜飞龙原锋辉许佩敏张阁西安菲尔特金属过滤材料股份有限公司陕西西安710201 空装驻新乡地区军事代表室河南新乡453000

综述了金属纤维纺织品的类型(机织物、针织物、烧结毡),重点介绍了金属纤维纺织品在电磁屏蔽、燃烧器、玻璃热弯成型、过滤等领域的应用,展望了金属纤维纺织品未来的发展方向和市场前景。

关键词：金属纤维纺织品电磁屏蔽过滤燃烧器

Photosynthate supply drives soil respiration of Fraxinus mandshurica seedlings in northeastern China： evidences from a shading and nitrogen addition experiment

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Journal of Forestry Research 2016年第6期27卷 1271-1276页

作者： Yanli Jing Dexin Guan Jiabing Wu Anzhi Wang Changjie Jin fenghui yuan Key Laboratory of Forest Ecology and Management Institute of Applied Ecology Chinese Academy of SciencesShenyang 110164 People's Republic of China University of Chinese Academy of Sciences Beijing 100049People's Republic of China

Improved understanding of the link between photosynthesis and below-ground processes is needed to better understand ecosystem carbon （C） cycling and its feedback to climate change. We conducted a short-term shading and nitrogen （N） addition experiment from June to September 2013 to investigate the effect of photosynthate supply by Manchurian Ash （Fraxinus mandshurica） seed- lings on soil respiration （SR）. Shading significantly reduced SR in early and middle growing season, but not in late growing season, leading to a decrease in mean SR by 24 % in N-unfertilized treatments. N addition increased mean SR by 42 % in un-shaded treatment. The stimulation of SR was largely attributed to accelerated autotrophic respiration by increasing photosynthesis, leaf area index and belowground biomass. Shading reduced mean SR by 32 % in N addition treatment. The strengthened shading effect on SR resulted from N addition was because of more photosynthates supply at low soil temperature. Our findings highlight the predominance of photosynthates supply in regulating the responses of C cycling to global change.

关键词： Autotrophic respiration Carbon Fertilization Shading Substrate supply

Robustness of the octupole collectivity in 144Ba within the cranking covariant density functional theory in 3D lattice

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Nuclear Science and Techniques 2024年第8期35卷 124-131页

作者： Ze‑Kai Li yuan‑yuan Wang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The octupole deformation and collectivity in octupole double-magic nucleus 144Ba are investigated using the Cranking covariant density functional theory in a three-dimensional lattice *** reduced B(E3)transition probability is implemented for the first time in semiclassical approximation based on the microscopically calculated electric octupole *** available data,including the I-ωrelation and electric transitional probabilities B(E2)and B(E3)are well ***,it is shown that the ground state of 144Ba exhibits axial octupole and quadrupole deformations that persist up to high spins(I≈24h).

关键词： Octupole collectivity Cranking covariant density functional theory Rotational spectrum Electric transitional probabilities

Collective Molecular Machines: Multidimensionality and Reconfigurability

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Nano-Micro Letters 2024年第8期16卷 309-340页

作者： Bin Wang yuan Lu Department of Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical *** the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense *** progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and ***,individual molecular machines are only capable of producing nanometer work and generally have only a single *** order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new *** this review,we comprehensively discuss recent developments in the collective behaviors of molecular *** particular,collective behavior is divided into two *** is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional *** other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale *** discuss design strategies for both modes and focus on the modulation of features and ***,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

MAUN:Memory-Augmented Deep Unfolding Network for Hyperspectral Image Reconstruction

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1139-1150页

作者： Qian Hu Jiayi Ma yuan Gao Junjun Jiang Yixuan yuan Electronic Information School Wuhan UniversityWuhan 430072China School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China Department of Electronic Engineering Chinese University of Hong KongHong Kong 999077China

Spectral compressive imaging has emerged as a powerful technique to collect the 3D spectral information as 2D *** algorithm for restoring the original 3D hyperspectral images(HSIs)from compressive measurements is pivotal in the imaging *** approaches painstakingly designed networks to directly map compressive measurements to HSIs,resulting in the lack of interpretability without exploiting the imaging *** some recent works have introduced the deep unfolding framework for explainable reconstruction,the performance of these methods is still limited by the weak information transmission between iterative *** this paper,we propose a Memory-Augmented deep Unfolding Network,termed MAUN,for explainable and accurate HSI ***,MAUN implements a novel CNN scheme to facilitate a better extrapolation step of the fast iterative shrinkage-thresholding algorithm,introducing an extra momentum incorporation step for each iteration to alleviate the information ***,to exploit the high correlation of intermediate images from neighboring iterations,we customize a cross-stage transformer(CSFormer)as the deep denoiser to simultaneously capture self-similarity from both in-stage and cross-stage features,which is the first attempt to model the long-distance dependencies between iteration *** experiments demonstrate that the proposed MAUN is superior to other state-of-the-art methods both visually and *** code is publicly available at https://***/HuQ1an/MAUN.

关键词： Deep folding iteration

Gradient microstructure and superior strength-ductility synergy of AZ61 magnesium alloy bars processed by radial forging with different deformation temperatures

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Journal of Materials Science & Technology 2024年第3期170卷 65-77页

作者： Jingfeng Zou Lifeng Ma Yanchun Zhu Ling Qin yuan yuan School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Heavy Machinery Engineering Research Center of the Ministry Education Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Engineering University of HullCottingham RdHull HU67RXUK National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China

Gradient microstructure modification is a cost-efficient strategy for high strength without compromising ductility,which is urgently needed in the fundamental science of engineering *** this study,heterogeneous structures of AZ61 alloy bars with anisotropic gradients(with different grain size distributions from the surface to the center)were observed to exhibit strong strength-ductility synergies under different deformation tem *** results reveal that the grain refinement process under mediumlow temperature deformation conditions(≤350℃)consists of four transition stages along the radial direction,i.e.,twin activations and deformation band formations,dislocation cells and pile-ups,ultrafine sub-grains,and randomly orientated quasi-micron *** deformation temperatures have a great influence on twin activations and deformation band formations,and the high temperature can easily provoke the initiation of non-basal *** deformation bands were determined as a primary nucleation site due to their highly unstable dislocation hindrance *** in combination with the Radial forging(RF)deformation process,the differences of dynamic precipitates can be attributed to microstructural difference and solubility limit of Al at different tem *** summarizing the tensile test results,the sample forged at 350℃exhibited the best strength-ductility synergy,exhibiting the highest elongation(EL)of 23.2%with a 251 MPa yield strength(YS)and 394 MPa ultimate tensile strength(UTS)in center region,and combined with the highest strength value of 256 MPa YS and 420 MPa UTS in the center region,while the EL was slightly degraded to 19.8%.

关键词： Gradient microstructure Radial forging Strength-ductility synergy Magnesium alloy Strengthening mechanism

Pyrolysis Empirical Modeling of Polyester Glass Fiber Reinforced Plastics Using Sestak-Berggren Model Method

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Journal of Thermal Science 2024年第2期33卷 725-738页

作者： NAN Wei JI Wenhui yuan Yanping yuan Zhongyuan SUN Yong School of Mechanical Engineering Southwest Jiaotong UniversityChengdu610031China CRRC Changchun Railway Vehicles Co. LtdChangchun130062China

Polyester Glass Fiber Reinforced Plastic(Polyester GFRP),a thermosetting plastic comprised of glass fiber and polyester polymer compounds,is extensively utilized in high-speed *** its pyrolysis mechanism is crucial as it significantly influences the combustion characteristics and fire safety ***,kinetic research on polyester GFRP primarily focuses on employing the Coats-Redfern method to derive a theoretical kinetic ***,the pyrolysis process of polyester GFRP is complex and the aforementioned theoretical model fails to accurately describe the pyrolysis ***,this study seeks to utilize the Sestak and Berggren(SB) model as a methodological approach to reveal the complex reaction mechanism during the pyrolysis *** on thermogravimetric analysis,the entire pyrolysis process of polyester GFRP is divided into two primary ***,model-free methods are employed to ascertain the activation energy and pre-exponential *** results show that the fitted empirical models of the two main pyrolysis stages are f(α)=(1-α)^(1.47)[-ln(1-α)]^(1.50) and f(α)=(1-α)^(1.77)[-ln(1-α)]^(1.72),*** predicted results are in good agreement with experimental data under different heating rates,which indicates that the empirical model can sufficiently describe the pyrolysis process of polyester GFRP.

关键词： polyester GFRP model-fitting methods empirical models pyrolysis