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Microscopic sand production simulation and visual sanding pattern description in weakly consolidated sandstone reservoirs

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Petroleum Science 2022年第1期19卷 279-295页

作者： chang-yin dong Bo Zhou Fan-Sheng Huang Lei Zhang Yi-Zhong Zhao Yang Song Jun-Yu Deng Key Laboratory of Unconventional Oil&Gas Development Ministry of EducationQingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Research Institute of Petroleum Engineering Technology Shengli BranchSINOPECDongying257000ShandongPR China Research Ltd.of Engineering Technology CNPCTianjin345000PR China

To visually describe the sanding pattern,this study constructs a new particle-scale microstructure model of weakly consolidated formation,and develop the corresponding methodology to simulate the sanding process and predict sand cavity *** microstructure model is a particle-objective model,which focuses on the random sedimentation of every sand *** the microstructure,every particle has its own size,sphericity and inclination *** is used to simulate the actual structure of cemented granular materials,which considers the heterogeneity and randomness of reservoir properties,provides the initial status for subsequent sanding *** the particle detachment criteria,the microscopic simulation of sanding can be visually implemented to investigate the pattern and cavity shapes caused by sand *** results indicate that sanding always starts initially from the borehole border,and then extends along the weakly consolidated plane,showing obvious characteristic of *** typical microscopic sanding patterns,concerning pore liquefaction,pseudo wormhole and continuous collapse,are proposed to illustrate the sanding mechanism in weakly consolidated *** nonuniformity of sanding performance depends on the heterogeneous distribution of reservoir properties,such as rock strength and particle ***,the three sanding patterns are verified by visually experimental *** proposed integrated methodology is capable of predicting and describing the sanding cavity shape of an oil well after long-term sanding production,and providing the focus objective of future sand control measure.

关键词： Weakly consolidated reservoir Particle-scale microstructure model Microcosmic sanding process simulation Visual sanding cavity description Sanding prediction Sand control optimization

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A study on the pathogen species and physiological races of tomato Fusarium wilt in Shanxi,China

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Journal of Integrative Agriculture 2018年第6期17卷 1380-1390页

作者： chang yin-dong DU Bin WANG Ling JI Pei XIE Yu-jie LI Xin-feng LI Zhi-gang WANG Jian-ming College of Agriculture Shanxi Agricultural University Department of Horticulture Taiyuan University Technology Center Yuncheng Sub-Center Shanxi Entry-Exit Inspection and Quarantine Bureau Department of Genetics and Biochemistry Clemson University

In order to clarify the main pathogens of tomato Fusarium wilt in Shanxi Province, China, morphological identification, elongation factor 1 alpha （EF-1α） sequence analysis, specific primer amplification and pathogenicity tests were applied to study the isolates which were recovered from diseased plants collected from 17 different districts of Shanxi Province. The results were as follows： 1） Through morphological and molecular identification, the following 7 species of Fusarium were identified： F. oxysporum, F. solani, F. verticillioides, F. subglutinans, F. chlamydosporum, F. sporotrichioides, and F. semitectum; 2） 56 isolates of F. oxysporum were identified using specific primer amplification, among which, 29, 5 and 6 isolates were respectively identified as F. oxysporum f. sp. lycopersici physiological race 1, race 2, and race 3; 3） pathogenicity test indicated the significant pathogenicity of F. oxysporum, F. solani, F. verticillioides, and F. subglutinans to tomato plant. Therefore, among these 4 species confirmed as pathogenic to tomato in Shanxi, the highest isolation rate （53.3％） corresponded to F. oxysporum. Three physiological species, race 1, race 2, and race 3 of F. oxysporum f. sp. lycopersici are detected in Shanxi, among which race 1 is the most widespread pathogen and is also considered as the predominant race.

关键词： tomato Fusarium wilt Fusarium oxysporum f. sp. lycopersici physiological races EF-1α sequence analysis specific primer amplification

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A sand-production control system for gas production from clayey silt hydrate reservoirs

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China Geology 2019年第2期2卷 121-132页

作者： Yan-long Li Neng-you Wu Fu-long Ning Gao-wei Hu chang-ling Liu chang-yin dong Jing-an Lu Key Laboratory for Gas Hydrate of Ministry of Natural Resources China Geological SurveyMinistry of Natural ResourcesQingdao Institute of Marine GeologyQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Faculty of Engineering China University of GeosciencesWuhan 430074China School of Petroleum Engineering China University of PetroleumQingdao 266580China Guangzhou Marine Geological Survey China Geological SurveyMinistry of Natural ResourcesGuangzhou 510075China

Sand production is a crucial problem during the process of extracting natural gas from hydrate reservoirs. To deal with sand-production problems systematically, a sand-production control system (SCS) is first proposed in this paper, specialized for pore-distributed clayey silt hydrate reservoirs. Secondly, a nodal system analysis method (NSAM) is applied to analyze the sand migration process during hydrate exploitation. The SCS is divided into three sub-systems, according to different sand migration mechanisms, and three key scientific problems and advances in SCS research in China Geological Survey are reviewed and analyzed. The maximum formation sanding rate, proper sand-control gravel size, and borehole blockage risk position were provided for clayey hydrate exploitation wells based on the SCS analysis. The SCS sub-systems are closely connected via bilateral coupling, and coordination of the subsystems is the basis of maintaining formation stability and prolonging the gas production cycle. Therefore, contradictory mitigation measures between sand production and operational systems should be considered preferentially. Some novel and efficient hydrate exploitation methods are needed to completely solve the contradictions caused by sand production.

关键词： Natural gas hydrate Hydrate exploitation Sand-production management Sand production Sand control Nodal system analysis

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Atomistic study of inverse size effect induced by interfacial plasticity in pearlitic multi-principal element alloy

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Rare Metals 2024年第7期43卷 3341-3355页

作者： Chen Yang Qiao-Sheng Xia Cun-Hong yin dong-Peng Hua College of Mechanical Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou UniversityGuiyang 550025China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China

Owing to the fine nano-laminated structure,the pearlitic multi-principal element alloy(PMPEA) exhibits excellent mechanical and tribological ***,the incomplete understanding of the size effect of its lamella thickness and the unclear understanding of the plasticity-interface interaction mechanism limit further optimization of *** this study,the FeCoNi/Ni_3Ti interface-mediated plastic deformation behavior in PMPEA and the variation of mechanical and tribological properties with lamella thickness within the nanoscale range using molecular dynamics(MD) simulation were *** results indicate that the mechanical and tribological properties of the PMPEA with lamella thicknesses below 10 nm have a significant inverse size effect,i.e.,the smaller the lamella thickness,the weaker the *** is because the plastic carrier-interface interaction mechanism changes from a strengthening mechanism that hinders dislocations to a weakening mechanism that promotes dislocations with the decreases in the lamella thickness,and the weakening effect becomes more pronounced as the lamella thickness decreases and the number of interfaces *** particular,the deformation behavior of Ni_3Ti lamellae changes from crystal-like to amorphous-like with decreasing ***,in the sample with larger lamella thickness,the occurrence of hierarchical slips in the body-centered cubic(BCC) phase due to the multiprincipal elements effect can better alleviate the stress concentration caused by the dislocation accumulation at the interface,so that the phase interface exhibits outstanding load-bearing *** the dislocation pattern in BCC phase shows a firm high-density cell,which makes the substrate exhibit a stable tribological response.

关键词： Multi-principal element alloy Nano-laminated structure Molecular dynamics simulation Nanoindentation and nanoscratch

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Effect of bipolar-plates design on corrosion,mass and heat transfer in proton-exchange membrane fuel cells and water electrolyzers:A review

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1599-1616页

作者： Jiuhong Zhang Xiejing Luo yingyu Ding Luqi chang Chaofang dong Key Laboratory for Corrosion and Protection(MOE) Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing 100083China

Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen ***-exchange membrane water electrolyzers(PEMWEs)are promising devices for hydrogen production,given their high efficiency,rapid responsiveness,and *** plates account for a relatively high percentage of the total cost and weight compared with other components of ***,optimization of their design may accelerate the promotion of *** paper reviews the advances in materials and flow-field design for bipolar ***,the working conditions of proton-exchange membrane fuel cells(PEMFCs)and PEMWEs are compared,including reaction direction,operating temperature,pressure,input/output,and ***,the current research status of bipolar-plate substrates and surface coatings is summarized,and some typical channel-rib flow fields and porous flow fields are ***,the effects of materials on mass and heat transfer and the possibility of reducing corrosion by improving the flow field structure are ***,this review discusses the potential directions of the development of bipolar-plate design,including material fabrication,flow-field geometry optimization using threedimensional printing,and surface-coating composition optimization based on computational materials science.

关键词： bipolar-plates flow design mass and heat transfer corrosion water electrolyzers fuel cells

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Biomimetic MXene membranes with negatively thermo-responsive switchable 2D nanochannels for graded molecular sieving

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Green Energy & Environment 2024年第6期9卷 1058-1067页

作者： Yi Wang Yangyang Wang chang Liu dongjian Shi Weifu dong Baoliang Peng Liangliang dong Mingqing Chen The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxiJiangsu214122China International Research Center for Photo-responsive Molecules and Materials Jiangnan UniversityWuxiJiangsu214122China Research Institute of Petroleum Exploration&Development(RIPED) PetroChina/Key Laboratory of Oilfield ChemistryCNPCBeijing100083China

Negatively thermo-responsive 2D membranes,which mimic the stomatal opening/closing of plants,have drawn substantial interest for tunable molecular separation ***,these membranes are still restricted significantly on account of low water permeability and poor dynamic tunability of 2D nanochannels under temperature ***,we present a biomimetic negatively thermo-responsive MXene membrane by covalently grafting poly(N-isopropylacrylamide)(PNIPAm)onto MXene *** uniformly grafted PNIPAm polymer chains can enlarge the interlayer spacings for increasing water permeability while also allowing more tunability of 2D nanochannels for enhancing the capability of gradually separating multiple molecules of different *** expected,the constructed membrane exhibits ultrahigh water permeance of 95.6 L m^(-2) h^(-1) bar^(-1) at 25℃,which is eight-fold higher than the state-of-the-art negatively thermoresponsive 2D ***,the highly temperature-tunable 2D nanochannels enable the constructed membrane to perform excellent graded molecular sieving for dye-and antibiotic-based ternary *** strategy provides new perspectives in engineering smart 2D membrane and expands the scope of temperature-responsive membranes,showing promising applications in micro/nanofluidics and molecular separation.

关键词： Thermo-responsive 2D membrane MXene nanosheets PNIPAm Temperature-tunable 2D nanochannels Graded molecular sieving

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Optimization of territorial space layout in China

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Journal of Geographical Sciences 2024年第9期34卷 1719-1738页

作者： dong yin JIN Gui DENG Xiangzheng Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education Fujian Normal UniversityFuzhou 350007China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China School of Economics and Management China University of GeosciencesWuhan 430079China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China

The evolution of territorial space is intrinsically linked to economic growth, societal welfare, and ecological preservation. In the context of escalating spatial conflicts and stringent resource limitations, resource efficiency has emerged as a fundamental pillar for the scientific optimization of territorial space layout. Drawing upon resource efficiency metrics from cities nationwide, this study constructs scenarios for territorial space development and conservation, assesses developmental capacity under varying preferences, and subsequently delineates strategic blueprints using an integrated “point-axis-area” approach. The findings reveal the following:(1) Resource efficiency in China has witnessed a consistent uptick, yet remains modest overall, with marked regional disparities.(2) Throughout the investigation period, developmental capacity has seen progressive enhancement, with a pronounced capacity in scenarios favoring development, radiating axially from urban conglomerates.(3) The layout of pivotal points and developmental axes has transitioned from a “tri-pillar” to a diamond configuration, with the coastal corridor, Harbin-Beijing-Guangzhou corridor, and the corridor along the Yangtze River standing out.(4) Strategic points progressively converge along key axes, whereas dominant regions exhibit clear differentiation on either side of the Hu Huanyong Line. By integrating elements of the territorial spatial structure,this paper proposes blueprints for “five horizontal and three vertical zones with eight cores and three areas,” “four horizontal and three vertical zones with six cores and three areas,”and “three horizontal and four vertical zones with five cores and three areas,” corresponding to scenarios of prioritizing development, status quo maintenance, and prioritizing conservation, respectively. The outcomes of this research offer a technical foundation and theoretical guidance for the pursuit of high-quality territorial space development and a vision

关键词： territorial space resource efficiency development and conservation developmental capacity territorial space blueprints China

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Mitigation of Deane and Hamill phenomenon in gallium nitride high-voltage power supply for electric propulsion system application

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High Voltage 2024年第1期9卷 252-265页

作者： Minghai dong Hui Li Shan yin Kye Yak See yingzhe Wu Xiong Xin School of Aeronautics&Astronautics University of Electronic Science and Technology of ChinaChengduChina School of Electrical&Electronic Engineering Nanyang Technological UniversitySingaporeSingapore School of Automation Engineering University of Electronic Science and Technology of ChinaChengduChina Innoscience(Shenzhen)Semiconductor Co.Ltd. ShenzhenChina

The step-up resonant converters are widely adopted to provide high voltage in kV-level for electric propulsion system due to their high efficiency,low mass,modularisation,and high-power *** bipolar Cockcroft-Walton voltage multiplier(BiCWVM)is a major circuit that steps up the voltage in the resonant ***,the diode nonlinearity in BiCWVM can introduce self-sustained quasi-periodic oscillations in the voltage and current waveforms,which is commonly known as the Deane and Hamill(DH)*** oscillation can lead to higher magnetic loss and control failure,and it is more likely to present in the gallium nitride-based converter due to the highfrequency *** authors aim to investigate and mitigate the DH phenomenon systematically so that proper mitigation can be *** facilitate the investigation,the circuit before the BiCWVM in the converter is derived and modelled as a voltage source v_(m)and a series inductor L_(sy).Also,the reverse recovery process of the diode in the BiCWVM can be represented by a piecewise-linear(PWL)model,with the simplified circuit and PWL model,the relationship between voltage and current under different operating conditions can be determined with *** relationship allows to understand the mechanism of diode reverse recovery in BiCWVM that leads to DH ***,a hybrid-/full-silicon carbide(SiC)design is proposed to mitigate the DH phenomenon,which is verified experimentally for a 300-kHz,5-W,20-V/1.5-kV GaN-based step-up resonant converter.

关键词： power resonant high

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Nonlinear Registration of Brain Magnetic Resonance Images with Cross Constraints of Intensity and Structure

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Computers, Materials & Continua 2024年第5期79卷 2295-2313页

作者： Han Zhou HongtaoXu Xinyue chang Wei Zhang Heng dong Digital Fujian Research Institute of Big Data forAgriculture and Forestry Fujian Agriculture and Forestry UniversityFuzhou350002China College of Computer and Information Science Fujian Agriculture and Forestry UniversityFuzhou350002China

Many deep learning-based registration methods rely on a single-stream encoder-decoder network for computing deformation fields between 3D ***,these methods often lack constraint information and overlook semantic consistency,limiting their *** address these issues,we present a novel approach for medical image registration called theDual-VoxelMorph,featuring a dual-channel cross-constraint *** innovative network utilizes both intensity and segmentation images,which share identical semantic information and feature *** encoder-decoder structures calculate deformation fields for intensity and segmentation images,as generated by the dual-channel cross-constraint *** design facilitates bidirectional communication between grayscale and segmentation information,enabling the model to better learn the corresponding grayscale and segmentation details of the same anatomical *** ensure semantic and directional consistency,we introduce constraints and apply the cosine similarity function to enhance semantic *** on four public datasets demonstrates superior performance compared to the baselinemethod,achieving Dice scores of 79.9%,64.5%,69.9%,and 63.5%for OASIS-1,OASIS-3,LPBA40,and ADNI,respectively.

关键词： Medical image registration cross constraint semantic consistency directional consistency dual-channel

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Strengthening mechanism and forming control of linear friction welded GH4169 alloy joints

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Chinese Journal of Aeronautics 2024年第4期37卷 609-626页

作者： Yu SU Xiawei YANG Tingxi MENG Xinyuan HE dong WU Wenya LI Shuo yin State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Friction Welding Technologies School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Manufacturing and Biomedical EngineeringParsons BuildingTrinity College DublinThe University of DublinDublin 2Ireland

Numerical simulation and experimental research on Linear Friction Welding(LFW) for GH4169 superalloy were carried out. Based on the joint microstructure and mechanical properties,a suitable welding process was determined, which provided an important theoretical basis for the manufacture and repair of aeroengine components such as the superalloy blisk. The results show that the joint strain rate gradually increases with the increase of welding frequency, and the deformation resistance of the thermoplastic metal increases in the welding process, resulting in the interface thermoplastic metal not being extruded in time to form a flash, so the joint shortening amount gradually decreases. The thermoplastic metal in the center of the welding surface is kept at high welding temperature for a long time, resulting in the decrease of the joint strength. The microhardness of the joint shows a “W” distribution perpendicular to the weld, and most of the joints break in the Thermo-Mechanically Affected Zone(TMAZ) with high tensile strength and low *** the welding area is increased without changing the aspect ratio of the welding surface, the interface peak temperature increases gradually, and the joint shortening amount decreases with the increase of the welding interface size.

关键词： Linear Friction Welding(LFW) Microstructure Mechanical properties Numerical simulation Joint shortening amount

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