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Water Science and Engineering 2019年第4期12卷 330-338页

作者： jing-chun feng Hua-ai Huang Yao Yin Ke Zhang Business School Hohai UniversityNanjing 211100China Institute of Project Management Hohai UniversityNanjing 211100China Jiangsu Provincial Collaborative Innovation Center of World Water Valley and Water Ecological Civilization Nanjing 211100China Guangxi Flood Control and Drought Relief Headquarters Nanning 530023China

Identification of security risk factors for small reservoirs is the basis for implementation of early warning *** manner of identification of the factors for small reservoirs is of practical significance when data are *** existing grey relational models have some disadvantages in measuring the correlation between categorical data *** this end,this paper introduces a new grey relational model to analyze heterogeneous *** this study,a set of security risk factors for small reservoirs was first constructed based on theoretical analysis,and heterogeneous data of these factors were recorded as *** sequences were regarded as random variables,and the information entropy and conditional entropy between sequences were measured to analyze the relational degree between risk ***,a new grey relational analysis model for heterogeneous data was constructed,and a comprehensive security risk factor identification method was developed.A case study of small reservoirs in Guangxi Zhuang Autonomous Region in China shows that the model constructed in this study is applicable to security risk factor identification for small reservoirs with heterogeneous and sparse data.

关键词： Security risk factor identification Heterogeneous data Grey relational analysis model Relational degree Information entropy Conditional entropy Small reservoir Guangxi

Deep-sea organisms research oriented by deep-sea technologies development

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Science Bulletin 2022年第17期67卷 1802-1816页

作者： jing-chun feng Jianzhen Liang Yanpeng Cai Si Zhang jingchuan Xue Zhifeng Yang Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China School of Ecology Environmentaland ResourcesGuangdong University of TechnologyGuangzhou 510006China South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China

Deep-sea environment,characterized by high pressures,extremely high/low temperatures,limited photosynthesis-generated organic matter,darkness,and high levels of corrosion,is home to flourishing special ecosystems in the ***,we illustrate how the deep-sea equipment offers insights into the study of life in the deep sea based on the work in the past five *** first describe how organisms in the deep sea are studied,even though it is highly difficult to get access to such extreme *** then explain the role of deep-sea technologies in advancing research on the evolution of organisms in hydrothermal vents,cold seeps,seamounts,oceanic trenches,and whale falls from the following perspectives:biological diversity,mechanisms of environmental adaptation,biological evolution,and ecosystem ***,to better understand the function and service of deep-sea organisms,and further conserve the special creatures under anthropologic activity and climate change,we highlight the importance of innovative deep-sea technologies to promote cutting-edge research on deep-sea organisms,and note the remaining challenges and developing directions for deep-sea equipment.

关键词： Deep sea Extreme life Equipment Biological diversity Environmental adaptation Ecosystem connectivity

Interactions of Microplastics and Methane Seepage in the Deep-Sea Environment

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Engineering 2023年第10期29卷 159-167页

作者： jing-chun feng Zhifeng Yang Wenliang Zhou Xingwei feng Fuwen Wei Bo Li Chuanxin Ma Si Zhang Linlin Xia Yanpeng Cai Yi Wang Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds Institute of Environmental and Ecological EngineeringGuangdong University of TechnologyGuangzhou 510006China Key Laboratory of Gas Hydrate Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640China Guangzhou Center for Gas Hydrate Research Chinese Academy of SciencesGuangzhou 510640China

Microplastics(MPs)are important exempla of the Anthropocene and are exerting an increasing impact on Earth’s carbon *** huge imbalance between the MPs floating on the marine surface and those that are estimated to have been introduced into the ocean necessitates a detailed assessment of marine MP ***,we demonstrate that cold seep sediments,which are characterized by methane fluid seepage and a chemosynthetic ecosystem,effectively capture and accommodate small-scale(<100μm)MPs,with 16 types of MPs being *** abundance of MPs in the surface of the sediment is higher in methane-seepage locations than in non-seepage *** seepage is beneficial to the accumulation,fragmentation,increased diversity,and aging of *** turn,the rough surfaces of MPs contribute to the sequestration of the electron acceptor ferric oxide,which is associated with the anaerobic oxidation of methane(AOM).The efficiency of the AOM determines whether the seeping methane(which has a greenhouse effect 83 times greater than that of CO_(2)over a 20-year period)can enter the atmosphere,which is important to the global methane cycle,since the deep-sea environment is regarded as the largest methane reservoir associated with natural gas hydrates.

关键词： Microplastics Anaerobic oxidation of methane Cold seeps Diversity index Fragmentation Gas hydrates

Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs

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Water Science and Engineering 2012年第3期5卷 350-360页

作者： jing-chun feng Ya-fang REN Zhong-nan DUAN Zhan-jun LIU Hai-yang LI Institute of Project Management Informationization Business School Hohai University Nanjing 211100 P. R. China Construction and Administration Bureau of South-to-North Water Diversion Middle Route Project Beijing 100053 P. R. China

According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably,

关键词： program establishment program management," bidding section construction period,critical path method (CPM) penaly model, South-to-North Water Diversion Project

Numerical Analysis of Perforation during Hydraulic Fracture Initiation Based on Continuous-Discontinuous Element Method

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 2103-2129页

作者： Rui Zhang Lixiang Wang jing Li chun feng Yiming Zhang School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou310018China Jinyun Institute Zhejiang Sci-Tech UniversityLishui321400China

Perforation is a pivotal technique employed to establish main flow channels within the reservoir formation at the outset of hydraulic fracturing *** perforation designs is critical for augmenting the efficacy of hydraulic fracturing and boosting oil or gas *** this study,we employ a hybrid finite-discrete element method,known as the continuous–discontinuous element method(CDEM),to simulate the initiation of post-perforation hydraulic fractures and to derive enhanced design *** model incorporates the four most prevalent perforation geometries,as delineated in an engineering technical ***-world perforations deviate from the ideal cylindrical shape,exhibiting variable cross-sectional profiles that typically manifest as an initial constriction followed by an expansion,a feature consistent across all four perforation *** simulations take into account variations in perforation hole geometries,cross-sectional diameters,and perforation *** findings show that perforations generated by the 39g DP3 HMX perforating bullet yield the lowest breakdown pressure,which inversely correlates with increases in sectional diameter and perforation ***,this study reveals the relationship between breakdown pressure and fracture degree,providing valuable insights for engineers and designers to refine perforation strategies.

关键词： Hydraulic fracturing real perforation shape breakdown pressure perforation layout design CDEM

Critical chain construction with multi-resource constraints based on portfolio technology in South-to-North Water Diversion Project

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Water Science and Engineering 2011年第2期4卷 225-236页

作者： jing-chun feng Lei LI Nan YANG Yu-zhen HONG Min PANG Xiong YAO Li-cheng WANG Business School Hohai University Nanjing 210098 P. R. China Construction and Administration Bureau of South-to-North Water Diversion Middle Route Project Beijing 100053 P. R. China

Recently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the system analysis theory and project portfolio theory, this paper discusses the creation of project portfolios based on the similarity principle and gives the definition of priority in multi-resource allocation based on quantitative analysis. A model with multi-resource constraints, which can be applied to the critical chain construction of the A-bid section in the South-to-North Water Diversion Project, was proposed. Contrast analysis with the comprehensive treatment construction method and aggressive treatment construction method was carried out. This paper also makes suggestions for further research directions and subjects, which will be useful in improving the theories in relevant research fields.

关键词： multi-resource constraints South-to-North Water Diversion Project project portfolio critical chain

Plasma-assisted ammonia synthesis under mild conditions for hydrogen and electricity storage:Mechanisms,pathways,and application prospects

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Frontiers in Energy 2024年第4期18卷 418-435页

作者： feng GONG Yuhang jing Rui XIAO Key Laboratory of Energy Thermal Conversion and Process Measurement and Control of the Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Ammonia,with its high hydrogen storage density of 17.7 wt.%(mass fraction),cleanliness,efficiency,and renewability,presents itself as a promising zero-carbon ***,the traditional Haber−Bosch(H−B)process for ammonia synthesis necessitates high temperature and pressure,resulting in over 420 million tons of carbon dioxide emissions annually,and relies on fossil fuel *** contrast,dielectric barrier discharge(DBD)plasma-assisted ammonia synthesis operates at low temperatures and atmospheric pressures,utilizing nitrogen and hydrogen radicals excited by energetic electrons,offering a potential alternative to the H−B *** method can be effectively coupled with renewable energy sources(such as solar and wind)for environmentally friendly,distributed,and efficient ammonia *** review delves into a comprehensive analysis of the low-temperature DBD plasma-assisted ammonia synthesis technology at atmospheric pressure,covering the reaction pathway,mechanism,and catalyst system involved in plasma nitrogen *** from current research,it evaluates the economic feasibility of the DBD plasmaassisted ammonia synthesis technology,analyzes existing dilemmas and challenges,and provides insights and recommendations for the future of nonthermal plasma ammonia processes.

关键词： plasma catalysis nitrogen fixation ammonia synthesis hydrogen storage catalyst carbon neutralization

Attractor for the Extensible Beam Equation with Nonlocal Weak Damping on Time–Dependent Space

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1115-1126页

作者： chun Xiang ZHAO feng Juan MENG Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013P.R.China School of Mathematics and Physics Jiangsu University of TechnologyChangzhou 213001P.R.China

In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at *** the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed *** results obtained essentially improve and complete some previous works.

关键词： Time-dependent attractor extensible beams equation nonlocal weak damping

Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion

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China Foundry 2024年第4期21卷 327-333页

作者： Yan-peng Wei Huai-qian Li jing-jing Han Ying-chun Ma Hao-ran Zhou jing-chang Cheng Jian Shi Zhi-quan Miao Bo Yu feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,*** results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TPMS energy absorption damping laser powder bed fusion

Z-scheme Bi_(4)O_(5)Br_(2)/NH_(2)-MIL-125(Ti)heterojunctions enable exceptional visible photocatalytic degradation of organic pollutant

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Rare Metals 2024年第7期43卷 3161-3172页

作者： feng Huang Muhammad Humayun Gang Li Ting-Ting Fan Wen-Lin Wang Yu-Lin Cao Anton Nikiforov chun-Dong Wang jing Wang Key Laboratory of Analytical Science and Technology of Hebei Province Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationState Key Laboratory of New Pharmaceutical Preparations and ExcipientsCollege of Chemistry and Materials ScienceHebei UniversityBaoding071002China Energy Water and Environment LabCollege of Humanities and SciencesPrince Sultan University11586 RiyadhSaudi Arabia Baoding Green Yijia Environmental Protection Technology Ltd Baoding 071051China Physics Laboratory Industrial Training CenterShenzhen Polytechnic UniversityShenzhen 518055China Department of Applied Physics Ghent University9000 GhentBelgium School of Integrated Circuits Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China

One key strategy to enhance photocatalytic performance is to improve the transfer and separation efficiency of photogenerated carriers by building optimized ***,novel Bi_(4)O_5Br_(2)/NH_(2)-MIL-125(Ti)Z-scheme heterojunctions are fabricated and used as photocatalysts for organic pollutant *** NH_(2)-MIL-125(Ti)nanosheets are exfoliated via a self-developed alkali solution stripping approach and then uniformly decorated on Bi_(4)O_(5)Br_(2).The as-prepared Bi_(4)O_(5)Br_(2)/NH_(2)-MIL-125(Ti)presents more than 90%degradation of various pollutants,outperforming the counterpart individual *** various characterization results suggest that the enhanced degradation rate is due to the more intimate face-to-face interfacial contact of the lamellar Z-scheme heterojunction materials,in which the migration path of carriers from the material's interior to the surface can be reduced,in turn enhancing migration efficiency and separation capability significantly.A possible photocatalytic reaction mechanism is proposed based on the photoelectric behaviors,radical trapping experiments and liquid chromatography mass spectrometry *** work promotes the development of new photocatalytic materials for heterojunctions with face-to-face interfacial contacts,as well as the effective purification of wastewater in environmental remediation.

关键词： Z-scheme heterojunctions Photocatalysis Alkaline solution stripping Bi_(4)O_(5)Br_(2) NH_(2)-MIL-125(Ti)