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珠江口海域重金属的河口化学研究——Ⅰ.珠江口海域水相中微量重金属的化学形态的研究

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海洋与湖沼 1982年第1期 19-25页

作者：郑建禄王肇鼎林植青李子江朱卓洪陈金斯中国科学院南海海洋研究所

珠江口海域是河水与海水交汇区域,环境非常复杂,要进行重金属的河口化学研究,首先必须了解其在河口区的化学形态及变化规律,才能在实验室进行模拟实验和理论计算。这对河口海域的环境保护是具有重要意义的。目前,对海水中微量金属的化... 详细信息

珠江口海域是河水与海水交汇区域,环境非常复杂,要进行重金属的河口化学研究,首先必须了解其在河口区的化学形态及变化规律,才能在实验室进行模拟实验和理论计算。这对河口海域的环境保护是具有重要意义的。目前,对海水中微量金属的化学形态研究颇为活跃,大体可分二大类。其研究方法见表1。

关键词：化学形态 Pb 化学种态重金属重有色金属河口化学珠江口海域

Interdecadal variation of drought patterns and associated influencing factors in the north-south transitional zone of China

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Journal of Geographical Sciences 2024年第7期34卷 1253-1279页

作者： DONG Qingdong zhu lianqi DUAN zheng wang liyuan chen Chaonan li Yanhong zhu Wenbo GURUNG Sher Bahadur The College of Geography and Environmental Science Henan UniversityKaifengHenan475004China Department of Physical Geography and Ecosystem Science Lund UniversityLundS-22362Sweden Central Department of Geography Tribhuvan UniversityKathmandu44600Nepal

In the context of global warming,escalating water cycles have led to a surge in drought frequency and ***,multidecadal fluctuations in drought and their multifaceted influencing factors remain inadequately *** study examined the multidecadal changes in drought characteristics(frequency,duration,and severity)and their geographical focal points within China's north-south transitional zone,the Qinling-Daba Mountains(QDM),from 1960 to 2017 using the Standardized Precipitation Evapotranspiration Index(SPEI).In addition,a suite of eight scenarios,correlation analysis,and wavelet coherence were used to identify the meteorological and circulation factors that influenced drought *** results indicate the following:(1)From 1960 to 2017,the QDM experienced significant interdecadal variations in drought frequency,duration,and severity,the climate was relatively humid before the 1990s,but drought intensified ***,the 1990s marked the period of the longest drought duration and greatest severity,while the years spanning 2010 to 2017 experienced the highest frequency of drought events.(2)Spatially,the Qinling Mountains,particularly the western Qinling Mountain,exhibited higher drought frequency,duration,and severity than the Daba *** disparity can be attributed to higher rates of temperature increase and precipitation decrease in the western Qinling Mountain.(3)Interdecadal variations in droughts in the QDM were directly influenced by the synergistic effects of interdecadal fluctuations in air temperature and *** factors modulate temperature and precipitation through phase transitions,thereby affecting drought dynamics in the *** Atlantic Multidecadal Oscillation emerges as the primary circulation factors influencing temperature changes,with a mid-1990s shift to a positive phase favoring *** East Asian Summer Monsoon and El Ni?o-Southern Oscillation are the main circulation factors a

关键词： drought standardized precipitation evapotranspiration index multidecadal shift transitional zone Qinling-Daba Mountains

A Framework Based on the DAO and NFT in Blockchain for Electronic Document Sharing

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2373-2395页

作者： lin chen Jiaming zhu Yuting Xu Huanqin zheng Shen Su Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China Engineering Research Center of lntegration and Application of Digital Learning Technology Ministry of EducationBeijing100816China

In the information age,electronic documents(e-documents)have become a popular alternative to paper documents due to their lower costs,higher dissemination rates,and ease of knowledge ***,digital copyright infringements occur frequently due to the ease of copying,which not only infringes on the rights of creators but also weakens their creative ***,it is crucial to establish an e-document sharing system that enforces copyright ***,the existing centralized system has outstanding vulnerabilities,and the plagiarism detection algorithm used cannot fully detect the context,semantics,style,and other factors of the *** watermark technology is only used as a means of infringement *** paper proposes a decentralized framework for e-document sharing based on decentralized autonomous organization(DAO)and non-fungible token(NFT)in *** use of blockchain as a distributed credit base resolves the vulnerabilities inherent in traditional centralized *** e-document evaluation and plagiarism detection mechanisms based on the DAO model effectively address challenges in comprehensive text information checks,thereby promoting the enhancement of e-document *** mechanism for protecting and circulating e-document copyrights using NFT technology ensures effective safeguarding of users’e-document copyrights and facilitates e-document ***,recognizing the security issues within the DAO governance mechanism,we introduce an innovative optimization *** experimentation,we validate the enhanced security of the optimized governance mechanism,reducing manipulation risks by up to 51%.Additionally,by utilizing evolutionary game analysis to deduce the equilibrium strategies of the framework,we discovered that adjusting the reward and penalty parameters of the incentive mechanism motivates creators to generate superior quality and unique e-documents,while evaluators are more likely to engage in

关键词： Electronic document sharing blockchain DAO NFT evolutionary game

Self-templating synthesis of biomass-based porous carbon nanotubes for energy storage and catalytic degradation applications

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Green Energy & Environment 2024年第3期9卷 584-595页

作者： Manman Xu Shiqi Fu Yukai Wen Wei li Qiongfang zhuo Haida zhu Zhikeng zheng Yuwen chen Anqi wang Kai Yan Research Centre for Eco-Environmental Engineering School of Environment and Civil EngineeringDongguan University of TechnologyDongguan523808China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou510275China

Dwindling energy sources and a worsening environment are huge global problems,and biomass wastes are an under-exploited source of material for both energy and material ***,self-template decoction dregs of Ganoderma lucidum-derived porous carbon nanotubes(ST-DDLGCs)were synthesized via a facile and scalable strategy in response to these ***-DDLGCs exhibited a large surface area(1731.51 m^(2)g^(-1))and high pore volume(0.76 cm^(3)g^(-1)),due to the interlacing tubular structures of precursors and extra-hierarchical porous structures on tube *** the ST-DDLGC/PMS system,the degradation efficiency of capecitabine(CAP)reached~97.3%within 120 ***,ST-DDLGCs displayed high catalytic activity over a wide pH range of 3–9,and strong anti-interference to these typical and ubiquitous anions in wastewater and natural water bodies(i.e.,H_(2)PO_(4)^(-),NO_(3)^(-),Cl^(-) and HCO_(3)^(-)),in which a ^(1)O_(2)-dominated oxidation was identified and non-radical mechanisms were ***,ST-DDLGC-based coin-type symmetrical supercapacitors exhibited outstanding electrochemical performance,with specific capacitances of up to 328.1 F g^(-1)at 0.5 A g^(-1),and cycling stability of up to 98.6%after 10,000 cycles at a current density of 2 A g^(-1).The superior properties of ST-DDLGCs could be attributed to the unique porous tubular structure,which facilitated mass transfer and presented numerous active *** results highlight ST-DDLGCs as a potential candidate for constructing inexpensive and advanced environmentally functional materials and energy storage devices.

关键词： Ganoderma lucidum residue Porous carbon nanotubes Self-template method Wastewater treatment Supercapacitor electrode

The dynamics beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 56-67页

作者： Zhen liu li-Hua wang Yong Jiang Ya-Jun Tong Hua-Chun zhu Te Ji Min chen zheng Jiang Xiang-Jun Wei Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China ShanghaiTech University Shanghai 201210China

The dynamics beamline(D-line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-XAS and SR-IR measurements at the same sample position on a millisecond time-resolved *** combined technique is effective for investigating rapid structural changes in atoms,electrons,and molecules in complicated disorder systems,such as those used in physics,chemistry,materials science,and extreme ***,ED-XAS and SR-IR can be used independently in the two branches of the *** ED-XAS branch is the first ED-XAS beamline in China,which uses a tapered undulator light source and can achieve approximately 2.5×10^(12)photons/s·300 eV BW@7.2 keV at the sample *** exchange-able polychromator operating in the Bragg-reflection or Laue-transmission configuration is used in different energy ranges to satisfy the requirements for beam size and energy *** focused beam size is approximately 3.5μm(H)×21.5μm(V),and the X-ray energy range is 5–25 *** one-and two-dimensional position-sensitive detectors with frame rates of up to 400 kHz enables time resolutions of tens of microseconds to be *** distinctive techniques,such as the concurrent measurement of in situ ED-XAS and infrared spectroscopy,time-resolved ED-XAS,high-pressure ED-XAS,XMCD,and pump-probe ED-XAS,can be applied to achieve different scientific goals.

关键词： ED-XAS SR-IR Time-resolved D-line SSRF

Expanding carbon neutrality strategies:Incorporating out-ofboundary emissions in city-level frameworks

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Environmental Science and Ecotechnology 2024年第4期20卷 145-153页

作者： Zhe Zhang Mingyu li li Zhang Yunfeng Zhou Shuying zhu chen Lv Yixuan zheng Bofeng Cai Jinnan wang Center for Carbon Neutrality Chinese Academy of Environmental PlanningBeijing100043China School of Environment Tsinghua UniversityBeijing100084China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing100084China R&D and International Cooperation Office Chinese Academy of Environmental PlanningBeijing100043China School of Economics and Management Beijing University of Chemical TechnologyBeijing100029China Center of Air Quality Simulation and System Analysis Chinese Academy of Environmental PlanningBeijing100043China

Cities are increasingly vital in global carbon mitigation efforts,yet few have specifically tailored carbon neutrality ***,out-of-boundary indirect greenhouse gas(GHG)emissions,aside from those related to electricity and heat imports,are often overlooked in existing pathways,despite their significance in comprehensive carbon mitigation *** this gap,here we introduce an integrated analysis framework focusing on both production and consumption-related GHG *** to Wuyishan,a service-oriented city in Southern China,this framework provides a holistic view of a city's carbon neutrality pathway,from a full-scope GHG emission *** findings reveal the equal importance of carbon reduction within and outside the city's boundaries,with out-of-boundary emissions accounting for 42%of Wuyishan's present total GHG *** insight highlights the necessity of including these external factors in GHG accounting and mitigation strategy *** framework serves as a practical tool for cities,particularly in developing countries,to craft effective carbon neutrality roadmaps that encompass the full spectrum of GHG emissions.

关键词： Greenhouse gas emissions Full-scope emission accounting Carbon neutrality pathway City-level

Tuning the product selectivity of dimethyl oxalate hydrogenation over WO_(x) modified Cu/SiO_(2) catalysts

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Journal of Energy Chemistry 2024年第10期97卷 128-138,I0004页

作者： zheng li zhuo Ma Yihui li Ziang Zhao Yuan Tan Ziyin liu Xingkun chen Nian Lei Huigang wang Wei Lu Hejun zhu Yunjie Ding Hangzhou Institute of Advanced Studies Zhejiang Normal UniversityHangzhou 311231ZhejiangChina Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Shaanxi Key Laboratory of Clean Energy Technology Utilization Yulin BranchDalian National Laboratory For Clean EnergyCASYulin 719199ShaanxiChina State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Product selectivity and reaction pathway are highly dependent on surface structure of heterogeneous *** vapor-phase hydrogenation of dimethyl oxalate(DMO),"EG route"(DMO→methyl glycolate(MG)ethylene glycol(EG)→ethanol(ET))and"MA route"(DMO→MG→methyl acetate(MA))were proposed over traditional Cu based catalysts and Mo-based or Fe-based catalysts,***,tunable yield of ET(93.7%)and MA(72.1%)were obtained through different reaction routes over WO_(x) modified Cu/SiO_(2) catalysts,and the corresponding reaction route was further proved by kinetic study and in-situ DRIFTS *** studies demonstrated that H_(2) activation ability,acid density and Cu-WO_(x) interaction on the catalysts were tuned by regulating the surface W density,which resulted in the different reaction pathway and product ***'s more,high yield of MA produced from DMO hydrogenation was firstly reported with the H_(2) pressure as low as 0.5 MPa.

关键词： Ethanol Dimethyl oxalate Selective hydrogenation Methyl acetate WCu/SiO_(2)catalyst

Multifunctional Film Assembled from N‑Doped Carbon Nanofiber with Co–N_(4)–O Single Atoms for Highly Efficient Electromagnetic Energy Attenuation

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Nano-Micro Letters 2024年第11期16卷 359-376页

作者： Jia Xu Bei li zheng Ma Xiao Zhang Chunling zhu Feng Yan Piaoping Yang Yujin chen College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001People’s Republic of China Key Laboratory of In‑Fiber Integrated Optics College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China

Single-atom materials have demonstrated attractive physicochemical ***,understanding the relationships between the coordination environment of single atoms and their properties at the atomic level remains a considerable ***,a facile waterassisted carbonization approach is developed to fabricate well-defined asymmetrically coordinated Co–N_(4)–O sites on biomass-derived carbon nanofiber(Co–N_(4)–O/NCF)for electromagnetic wave(EMW)*** such nanofiber,one atomically dispersed Co site is coordinated with four N atoms in the graphene basal plane and one oxygen atom in the axial ***-depth experimental and theoretical studies reveal that the axial Co–O coordination breaks the charge distribution symmetry in the planar porphyrin-like Co–N_(4) structure,leading to significantly enhanced dielectric polarization loss relevant to the planar Co–N_(4) ***,the film based on Co–N_(4)–O/NCF exhibits light weight,flexibility,excellent mechanical properties,great thermal insulating feature,and excellent EMW absorption with a reflection loss of−45.82 dB along with an effective absorption bandwidth of 4.8 *** findings of this work offer insight into the relationships between the single-atom coordination environment and the dielectric performance,and the proposed strategy can be extended toward the engineering of asymmetrically coordinated single atoms for various applications.

关键词： Co single atoms Asymmetric coordination structure Axial oxygen coordination Electromagnetic wave absorption Multifunctional film

6DOF pose estimation of a 3D rigid object based on edge-enhanced point pair features

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Computational Visual Media 2024年第1期10卷 61-77页

作者： chenyi liu Fei chen Lu Deng Renjiao Yi lintao zheng chenyang zhu Jia wang Kai Xu College of Computing National University of Defense TechnologyChangsha410073China Department of Spine Surgery the Second Xiangya HospitalCentral South UniversityChangsha410011China Clinical Nursing Teaching and Research Section the Second Xiangya HospitalChangsha410011China College of Meteorology and Oceanography National University of Defense TechnologyChangsha410073China Beijing Institute of Tracking and Communication Technology Beijing100094China

The point pair feature(PPF)is widely used for 6D pose *** this paper,we propose an efficient 6D pose estimation method based on the PPF *** introduce a well-targeted down-sampling strategy that focuses on edge areas for efficient feature extraction for complex geometry.A pose hypothesis validation approach is proposed to resolve ambiguity due to symmetry by calculating the edge matching *** perform evaluations on two challenging datasets and one real-world collected dataset,demonstrating the superiority of our method for pose estimation for geometrically complex,occluded,symmetrical *** further validate our method by applying it to simulated punctures.

关键词： point pair feature(PPF) pose estimation object recognition 3D point cloud