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Journal of Energy Chemistry 2021年第7期30卷 629-635页

作者： Ruguang Wang yuanyuan yang yang Zhao Liujing yang Pengfei Yin Jing Mao Tao Ling Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education School of Materials Science and EngineeringTianjin UniversityTianjin 300072China Department of Chemistry City University of Hong KongKowloonHong KongChina

Atomically dispersed iron-nitrogen-carbon(Fe-N-C) catalysts have emerged as the most promising alternative to the expensive Pt-based catalysts for the oxygen reduction reaction(ORR) in proton exchange membrane fuel cells(PEMFCs),however suffer from low site density of active Fe-N4 moiety and limited mass transport during the catalytic *** address these challenges,we report a three-dimensional(3D) metal-organic frameworks(MOF)-derived Fe-N-C single-atom *** this well-designed Fe-N-C catalyst,the micro-scale interconnected skeleton,the nano-scale ordered pores and the atomic-scale abundant carbon edge defects inside the skeleton significantly enhance the site density of active Fe-N4 moiety,thus improving the Fe utilization in the final ***,the combination of the above mentioned micro-and nano-scale structures greatly facilitates the mass transport in the 3D Fe-N-C ***,the multiscale engineered Fe-N-C single-atom catalyst achieves excellent ORR performance under acidic condition and affords a significantly enhanced current density and power density in *** findings may open new opportunities for the rational design of FeN-C catalysts through multiscale structural engineering.

关键词： Fe–N–C catalyst Fe-N4 Proton exchange membrane fuel cells Oxygen reduction reaction Single-atom catalyst

Regional land ecological security evaluation and ecological poverty alleviation practice:A case study of yangxian County in Shaanxi Province,China

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Journal of Geographical Sciences 2022年第4期32卷 682-700页

作者： ZHANG Xinrong WANG Yongsheng YUAN Xuefeng yang yuanyuan School of Earth Science and Resources Chang'an UniversityXi'an 710054China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China School of Land Engineering Chang'an UniversityXi'an 710054China Key Laboratory of Degraded and Unused Land Consolidation Engineering Xi'an 710054China

Land ecological security(LES)is an important part of China’s ecological civilization construction,which plays a vital role in ensuring the sustainable development of its society and *** on the Driving force-Pressure-State-Impact-Response(DPSIR)framework,this study quantified the spatiotemporal changes of LES in 28 counties of the southern Shaanxi Province from 2009 to *** influencing factors of LES in yangxian County were explored to clarify the mechanisms that rely on the land ecological advantages to develop organic agriculture and boost poverty *** show that the LES of yangxian always ranked in the top six in 28 counties of the southern Shaanxi region during 2009–*** LES in yangxian increased from 0.385 in 2009 to 0.533 in 2018,and the LES level changed from relatively unsafe to *** indicators of rural per capita net income,grain output per unit area of arable land,and grazing intensity could explain 99.8%of the LES variance in *** on ecological resources,yangxian increased farmers’income and boosted alleviation of poverty through innovative land policies,developing organic agriculture,and rural *** findings will provide theoretical support and model reference for balancing ecological protection and poverty alleviation in restricted development zones.

关键词： land ecological security DPSIR framework organic agriculture ecological poverty alleviation yangxian County

Detecting Regional Deep Ocean Warming below 2000 Meter Based on Altimetry,GRACE,Argo,and CTD Data

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Advances in Atmospheric Sciences 2021年第10期38卷 1778-1790页

作者： yuanyuan yang Min ZHONG Wei FENG Dapeng MU State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and GeophysicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China University of the Chinese Academy of Sciences Beijing 100049China School of Geospatial Engineering and Science Sun Yat-sen UniversityZhuhai 519082China Institute of Space Sciences Shandong UniversityWeihai 264209China

The deep ocean below 2000 m is a large water body with the sparsest data coverage,challenging the closure of the sea-level budget and the estimation of the Earth’s energy *** the deep ocean below 2000 m is warming globally has been debated in the recent ***,as the regional signals are generally larger than the global average,it is intriguing to investigate the regional temperature ***,we adopt an indirect method that combines altimetry,GRACE,and Argo data to examine the global and regional deep ocean temperature changes below 2000 *** consistency between high-quality conductivity-temperature-depth(CTD)data from repeated hydrographic sections and our results confirms the validity of the indirect *** find that the deep oceans are warming in the Middle East Indian Ocean,the subtropical North and Southwest Pacific,and the Northeast Atlantic,but cooling in the Northwest Atlantic and Southern oceans from 2005 to 2015.

关键词： deep ocean warming GRACE Argo GO-SHIP altimetry

Micro-rocket robot with all-optic actuating and tracking in blood

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Light(Science & Applications) 2020年第1期9卷 1229-1238页

作者： Dengfeng Li Chao Liu yuanyuan yang Lidai Wang Yajing Shen Department of Biomedical Engineering City University of Hong Kong999077 Hong KongChina City University of Hong Kong Shenzhen Research Institute Shenzhen 518057China

Micro/nanorobots have long been expected to reach all parts of the human body through blood vessels for medical treatment or ***,in the current stage,it is still challenging to drive a microrobot in viscous media at high speed and difficult to observe the shape and position of a single microrobot once it enters the ***,we propose a new micro-rocket robot and an all-optic driving and imaging system that can actuate and track it in blood with microscale *** achieve a high driving force,we engineer the microrobot to have a rocket-like tripletube *** to the interface design,the 3D-printed micro-rocket can reach a moving speed of 2.8 mm/s(62 body lengths per second)under near-infrared light actuation in a blood-mimicking viscous glycerol *** also show that the micro-rocket robot is successfully tracked at a 3.2-μm resolution with an optical-resolution photoacoustic microscope in *** work paves the way for microrobot design,actuation,and tracking in the blood environment,which may broaden the scope of microrobotic applications in the biomedical field.

关键词： structure robot driving

Use of Intensity Analysis to Measure Land Use Changes from 1932 to 2005 in Zhenlai County, Northeast China

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Chinese Geographical Science 2017年第3期27卷 441-455页

作者： yang yuanyuan LIU Yansui XU Di ZHANG Shuwen Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources Science and Technology Beijing Normal University Urban Development Research Institute Shanghai Normal University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

Analyzing spatiotemporal dynamics of land use and land cover over time is widely recognized as important to better understand and provide solutions for social, economic, and environmental problems, especially in ecologically fragile region. In this paper, a case study was taken in Zhenlai County, which is a part of farming-pastoral ecotone of Northeast China. This study seeks to use multi-temporal satellite images and other data from various sources to analyze spatiotemporal changes from 1932 to 2005, and applied a quantitative methodology named intensity analysis in the time scale of decades at three levels: time interval, category, and transition. The findings of the case study are as follows: 1) the interval level of intensity analysis revealed that the annual rate of overall change was relatively fast in 1932–1954 and 1954–1976 time intervals. 2) The category level showed that arable land experienced less intensively gains and losses if the overall change was to have been distributed uniformly across the landscape while the gains and losses of forest land, grassland, water, settlement, wetland and other unused land were not consistent and stationary across the four time intervals. 3) The transition level illustrated that arable land expanded at the expense of grassland before 2000 while it gained intensively from wetland from 2000 to 2005. Settlement targets arable land and avoids grassland, water, wetland and other unused land. Besides, the loss of grassland was intensively targeted by arable land, forest land and wetland in the study period while the loss of wetland was targeted by water except for the time interval of 1976–2000. 4) During the early reclamation period, land use change of the study area was mainly affected by the policy, institutional and political factors, followed by the natural disasters.

关键词： intensity analysis land use and land cover change pattern driving forces Northeast China

The code of targeted poverty alleviation in China:A geography perspective

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Geography and Sustainability 2021年第4期2卷 243-253页

作者： yuanyuan yang Yansui Liu Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101China

Geography is suitable for the study of sustainability from a transdisciplinary perspective,which takes the human-land relationship as the core *** a key obstacle to rural sustainability,poverty is an external manifestation of the coupling maladjustment of elements in human-land territorial *** the world’s largest developing country,China eradicated extreme poverty in 2020 and made significant contributions to global poverty *** over the last eight years,China has implemented a targeted poverty alleviation(TPA)strategy and has continuously promoted theoretical,organizational and institutional innovations for poverty *** the perspective of geography,this paper extracts the experiences of China’s TPA strategy,represented by the"5W2H"*** research concludes that:(1)Precise identification,as the foundation of TPA,aims to in-troduce a registration system to obtain records of all poor households and then answer the"5W"(what,where,why,who,when)issues of the geography of poverty.(2)Precise assistance is the key of TPA,which aims to solve the issue of"how to offer help and support".The barriers to escaping poverty can be accomplished through poli-cies and measures that focus on the diverse causes of poverty and considering different situations.(3)Accurate assessments are an essential means of TPA,relevant to solve"how to measure the end of poverty alleviation",and third-party evaluations play an important role in improving the accuracy of poverty alleviation.(4)The TPA mechanism lies in reconstructing the human-land-industry structures in the impoverished areal *** is urgent to introduce China’s successful experience and typical modes of TPA for global human-earth system coordination and sustainable development and contribute to building a community of human destiny.

关键词： Targeted poverty alleviation Sustainable development China Geography Experience

China’s rural revitalization and development:Theory,technology and management

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Journal of Geographical Sciences 2020年第12期30卷 1923-1942页

作者： LIU Yansui ZANG Yuzhu yang yuanyuan Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

The urban-rural transformation from dichotomy to integration is a gradual *** rural areas in many countries,Chinese rural society is experiencing a decline in all spheres due to depopulation,aging,lack of economic opportunity,and so *** at solving the serious rural issues,China proposed the implementation of a rural revitalization strategy and the promotion of an integrated urban-rural development for the first time in *** proposal marks the transformation of the urban-rural relationship,and the integrated urban-rural development reflects a significant conceptual *** on issues of rural decline are urgently needed to determine the most effective method for rural revitalization and development from the perspective of the urban-rural *** this context,this paper focuses on studying the theory,technology and management of rural revitalization and *** construct a theoretical framework for urban-rural integration based on population-land-industry-right between the urban and rural systems,regarding land engineering for land capacity building as the technical support and the rural land system reform and reconstruction as the policy support for *** research will provide theoretical support for the implementation of China's rural revitalization strategy.

关键词： rural revitalization rural decline urban-rural integration land capacity building land consolidation engineering China

Exploring Attentive Siamese LSTM for Low-Resource Text Plagiarism Detection

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Data Intelligence 2024年第2期6卷 488-503页

作者： Wei Bao Jian Dong yang Xu yuanyuan yang Xiaoke Qi China Electronics Standardization Institute Beijing 100007China Beihang University Beijing 100191China Bohai University Jinzhou 121013China School of Information Management for Law China University of Political Science and LawBeijing 102249China

Low-resource text plagiarism detection faces a significant challenge due to the limited availability of labeled data for *** task requires the development of sophisticated algorithms capable of identifying similarities and differences in texts,particularly in the realm of semantic rewriting and translation-based plagiarism *** this paper,we present an enhanced attentive Siamese Long Short-Term Memory(LSTM)network designed for Tibetan-Chinese plagiarism *** approach begins with the introduction of translation-based data augmentation,aimed at expanding the bilingual training ***,we propose a pre-detection method leveraging abstract document vectors to enhance detection ***,we introduce an improved attentive Siamese LSTM network tailored for Tibetan-Chinese plagiarism *** conduct comprehensive experiments to showcase the effectiveness of our proposed plagiarism detection framework.

关键词： Text plagiarism detection Low resource Siamese Long Short-Term Memory Tibetan-Chinese

Effect of SiC particle addition on microstructure of Mg_2Si/Al composite

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China Foundry 2014年第2期11卷 91-97页

作者： Zhao Yuguang Liu Xiaobo yang yuanyuan Bian Tianjun College of Materials Science and Engineering Jilin University College of Mechanical Engineering Beihua University

In the present study, by adding SiC particles into AI-Si-Mg melt, Mg2Si and SiC particles hybrid reinforced AI matrix composites were fabricated through the Mg2Si in situ synthesis in melt combined with the SiC ex situ stir casting. The as-cast microstructure containing primary Mg2Si and SiC particles that distribute homogenously in AI matrix was successfully achieved. The effects of SiC particle addition on the microstructure of Mg2Si/AI composites were investigated by using scanning electron microscopy （SEM） and XRD. The results show that, with increasing the fraction of the SiC particles from 5wt.% to 10wt.%, the morphologies of the primary Mg2Si particulates in the prepared samples remain polygonal, but the size of the primary phase decreases slightly. However, when the SiC particle addition reaches 15wt.%, the morphologies of the primary Mg2Si particulates change partially from polygonal to quadrangular with a decrease in size from 50 pm to 30 μm. The size of primary AI dendrites decreases with increasing fraction of the SiC particles from 0wt.% to 15wt.%. The morphology of the eutectic Mg2Si phase changes from a fiber-form to a short fiber-form and/or a dot-like shape with increasing fraction of the SiC particles. Furthermore, no significant change in dendrite arm spacing （DAS） was observed in the presence of SiC particles.

关键词： Mg2Si/Al matrix composite SiC particles microstructure solidifi cation

Theranostic nanoparticles with tumor-specific enzyme-triggered size reduction and drug release to perform photothermal therapy for breast cancer treatment

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Acta Pharmaceutica Sinica B 2019年第2期9卷 410-420页

作者： Rui Liu Chuan Hu yuanyuan yang Jingqing Zhang Huile Gao Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan University Chongqing Research Center for Pharmaceutical Engineering Chongqing Medical University

Although progress has been indeed made by nanomedicines, their efficacies for cancer treatment remain low, consequently leading to failures in translation to clinic. To improve the drug delivery efficiency,nanoparticles need to change size so as to fully utilize the enhanced permeability and retention(EPR) effect of solid tumor, which is the golden principle of nanoparticles used for cancer treatment. Herein, we employed cationic small-sized red emission bovine serum albumin(BSA) protected gold nanocluster(Au NC@CBSA,21.06 nm) to both load indocyanine green(ICG) and act as imaging probe to realize theranostic. Then Au NC@CBSA-ICG was fabricated with negatively charged hyaluronic acid(HA) to form Au NC@CBSAICG@HA, which was about 200 nm to easily retain at tumor site and could be degraded by tumor-specific hyaluronidase into small nanoparticles for deep tumor penetration. The HA shell also endowed Au NC@CBSA-ICG@HA with actively targeting ability and hyaluronidase-dependent drug release. Furthermore, the quenching and recovery of fluorescence revealed the interaction between ICG and carrier, which was essential for the investigation of pharmacokinetic profiles. No matter in vitro or in vivo, Au NC@CBSAICG@HA showed markedly anti-tumor effect, and could suppress 95.0% of tumor growth on mice breast cancer model. All results demonstrated Au NC@CBSA-ICG@HA was potential for breast cancer therapy.

关键词： Size-shrinkage Drug release Photothermal therapy Theranostic Breast cancer