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Influences of shale microstructure on mechanical properties and bedding fractures distribution

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petroleum Science 2024年第3期21卷 1944-1954页

作者： Ming-Zhe Gu Mao sheng Shi-Zhong Cheng Fan-Hao gong Gen-sheng Li State Key Laboratory of petroleum Resources and Engineering China University of Petroleum-BeijingBeijing2249China College of petroleum Engineering China University of Petroleum-BeijingBeijing102249China Shenyang Center of China Geological Survey ShenyangLiaoning110034China

The difference in microstructure leads to the diversity of shale mechanical properties and bedding fractures distribution *** this paper,the microstructure and mechanical properties of Longmaxi marine shale and Qingshankou continental shale were studied by X-ray diffractometer(XRD),field emission scanning electron microscope(FE-SEM)with mineral analysis system,and ***,the typical bedding layers area was properly stratified using Focused Ion Beam(FIB),and the effects of microstructure and mechanical properties on the distribution patterns of bedding fractures were *** results show that the Longmaxi marine shale sample contains more clay mineral grains,while the Qingshankou continental shale sample contains more hard brittle mineral grains such as *** Longmaxi marine shale sample,hard brittle minerals with grain sizes larger than 20μm is18.24%and those with grain sizes smaller than 20μm is 16.22%.For Qingshankou continental shale sample,hard brittle minerals with grain sizes larger than 20μm is 40.7%and those with grain sizes smaller than 20μm is 11.82%.In comparison to the Qingshankou continental shale sample,the Longmaxi marine shale sample has a lower modulus,hardness,and *** shales are formed by alternating coarse-grained and fine-grained layers during *** average single-layer thickness of Longmaxi marine shale sample is greater than Qingshankou continental shale *** two types of shale have similar bedding fractures distribution patterns and fractures tend to occur in the transition zone from coarse-grained to fine-grained *** orientation of the fracture is usually parallel to the bedding plane and detour occurs in the presence of hard brittle *** fracture distribution density of the Longmaxi marine shale sample is lower than that of the Qingshankou continental shale sample due to the strong heterogeneity of the Qingshankou continental *** current resea

关键词： Shale Nanoindentation Microstructure Mechanical property Fracture

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang Zhi-hua gong Quan Li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 Mpa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

High-temperature oxidation resistance of Si-coated C/SiC composites

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Rare Metals 2024年第9期43卷 4566-4572页

作者： Jie Xiao Hua-Yue Zhang sheng-Kai gong Hui-Bin Xu Hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structure Materials and protective Coatings(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China

In this paper,Si coatings were sprayed onto C/SiC composite substrates by atmospheric plasma spraying(ApS).The high-temperature oxidation behavior of the substrate and coating at temperatures of 1100 and 1300℃was also *** C/SiC ceramic matrix composite will be damaged seriously and even failed due to the oxidation of carbon fibers in *** Si coating effectively improved the oxidation resistance of the C/SiC substrate in the high-temperature oxidation *** effect of the thickness of the Si coatings on the oxidation resistance was *** 150-μm coating is proved to enable the substrate to have the lowest oxidation weight loss and the best oxidation resistance after static oxidation for 5 h.

关键词： Ceramic matrix composites(CMCs) Carbon fiber Si coating Oxidation plasma spray

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research International 2024年第2期31卷 329-341页

作者： Jin-sheng Liu Zhen-xing Xing gong-jin Cheng Xue-yong Ding Xiang-xin Xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree phase transformation Micromorphology Oxidation path pore structure

Stable hydrogen-bonded organic frameworks and their photo-and electro-responses

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Nano Research 2024年第8期17卷 7675-7699页

作者： Ying Hou Xin-Song Huang sheng-Hao gong Chen Liu Yangyang Liu Tian-Fu Liu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry and Biochemistry California State UniversityLos AngelesCalifornia 90032USA College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China

Hydrogen-bonded organic frameworks(HOFs)are a recent class of porous materials that have garnered considerable research interest owing to their distinctive *** can be constructed through judicious selection of H-bonding motifs,which are further enforced by other weak intermolecular interactions such asπ–πstacking,van der Waals forces,and framework *** advantage of these interactions,we can expand the functional field of HOFs by introducing active ***,researchers have made substantial advancements in using HOFs for chemical sensing,catalysis,proton conduction,biological applications,and *** low bonding energy of H-bonds allows for precise control over the concentration of ligands in solvents,forming diverse HOF *** varied structures offer significant advantages for producing HOFs with photo-responsive and electro-responsive ***,the presence of H-bonds in HOFs results in their inherent lower stability compared to metal-organic frameworks(MOFs)and covalent-organic frameworks(COFs)formed via coordination and covalent bonds,*** a result,the pursuit of stable and innovative HOF materials with novel functional sites remains an ongoing *** review provides an overview of recent research progress in the development of new strategies for stable HOF synthesis and applications of HOFs with stimuli-responsive *** first classified all synthetic methods reported to date and discussed the stable HOFs synthesized,as well as their unique properties and *** addition,we summarized the applications of HOFs utilizing their synergistic responses to external stimuli,including photo,electrical,pressure,and chemical *** systematically reviewed stable HOF synthesis and applications,which may lead to a deeper understanding of the structure–activity relationship for these materials and guide future HOF design.

关键词： stable hydrogen-bonded organic frameworks(HOFs) photo-response electro-response photoelectric synergistic response

Stress sensitivity analysis for a wide-chord fan blade using an adjoint method

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Chinese Journal of Aeronautics 2024年第10期37卷 103-117页

作者： Han YAng Shoujia gong Yi LI Junxing TAng Dingxi WAng sheng HUAng Shenren XU School of power and Energy Northwestern Polytechnical UniversityXi’an 710129China

High-performance compressor design is best achieved with a good trade-off between aerodynamic and structural considerations,which requires efficient and accurate multidisciplinary design and optimization *** advanced compressors are defined with a large design space,their optimization is most efficiently achieved using a gradient-based approach,where the gradient can be computed using an adjoint method,at a cost nearly independent of the dimension of the design *** the adjoint method has been widely used for aerodynamic shape optimization,its use for structural shape optimizations of compressor blades has not been as well *** paper discussed a discrete adjoint solver for structural sensitivity analysis developed within the opensource Computational Structural Mechanics(CSM)software CalculiX,and proposed an efficient stress sensitivity analysis method based on the Finite Element Method(FEM)using *** proposed method is applied to compute the stress sensitivity of a wide-chord fan blade in a highbypass-ratio *** accuracy of the adjoint-based stress sensitivity is verified against central finite *** terms of computational efficiency,the adjoint approach is about 4.5 times more efficient than the conventional approach using finite *** works marks an important step towards fluid-structural coupled adjoint optimization of wide-chord fan blades.

关键词： Adjoint method Multidisciplinary optimization Stress sensitivity analysis Finite element method Shape optimization

Conquer coronary artery perforation with magic hands

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Journal of Geriatric Cardiology 2024年第4期21卷 379-386页

作者： Yi-Lun ZOU Jian-Qiang LI Ding-Yu WAng Yong-Tai gong Li sheng Yue LI Department of Cardiology the First Affiliated Hospital of Harbin Medical UniversityHarbinChina

Coronary artery perforation(CAp) poses a significant challenge for interventional cardiologists. Management of CAp depends on the location and severity of the perforation. The conventional method for addressing the perforation of large vessels involves the placement of a covered stent, while the perforation of distal and collateral vessels is typically managed using coils, autologous skin, subcutaneous fat, microspheres, gelatin sp.nge, thrombin or other substances. However, the above techniques have certain limitations and are not applicable in all scenarios. Our team has developed a range of innovative strategies for effectively managing CAp. This article provides an insightful review of the various tips and tricks for the treatment of CAp.

关键词： coronary sp.nge perforation

Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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petroleum Science 2024年第1期21卷 609-620页

作者： Fu-Cheng Deng Fu-Lin Gui Bai-Tao Fan Lei Wen sheng-Hong Chen Ning gong Yun-Chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： punching screen plugging CFD-DEM Size parameter Sand control

Brain-inspired artificial intelligence research: A review

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Science China(Technological Sciences) 2024年第8期67卷 2282-2296页

作者： WAng GuoYin BAO HuaNan LIU Qun ZHOU Tiangang WU Si HUAng TieJun YU ZhaoFei LU CeWu gong YiHong ZHAng ZhaoXiang HE sheng Chongqing Key Laboratory of Computational Intelligence Chongqing University of Posts and TelecommunicationsChongqing 400065China Key Laboratory of Cyberspace Big Data Intelligent Security Chongqing University of Posts and TelecommunicationsChongqing 400065China College of Computer and Information Science Chongqing Normal UniversityChongqing 401331China State Key Laboratory of Brain and Cognitive Science Institute of BiophysicsChinese Academy of SciencesBeijing 100101China School of psychological and Cognitive Sciences Peking UniversityBeijing 100871China State Key Laboratory of Multimedia Information processing School of Computer SciencePeking UniversityBeijing 100871China Department of Computer Science School of ElectronicsInformation and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Faculty of Electronic and Information Engineering Xi’an Jiaotong UniversityXi’an 710049China The Center for Research on Intelligent perception and Computing Institute of AutomationChinese Academy of SciencesBeijing 100190China Institute of Biophysics Chinese Academy of SciencesBeijing 100101China

Artificial intelligence(AI) systems surpass certain human intelligence abilities in a statistical sense as a whole, but are not yet the true realization of these human intelligence abilities and behaviors. There are differences, and even contradictions, between the cognition and behavior of AI systems and humans. With the goal of achieving general AI, this study contains a review of the role of cognitive science in inspiring the development of the three mainstream academic branches of AI based on the three-layer framework proposed by David Marr, and the limitations of the current development of AI are explored and analyzed. The differences and inconsistencies between the cognition mechanisms of the human brain and the computation mechanisms of AI systems are analyzed. They are found to be the cause of the differences and contradictions between the cognition and behavior of AI systems and humans. Additionally, eight important research directions and their scientific issues that need to focus on braininspired AI research are proposed: highly imitated bionic information processing, a large-scale deep learning model that balances structure and function, multi-granularity joint problem solving bidirectionally driven by data and knowledge, AI models that simulate specific brain structures, a collaborative processing mechanism with the physical separation of perceptual processing and interpretive analysis, embodied intelligence that integrates the brain cognitive mechanism and AI computation mechanisms,intelligence simulation from individual intelligence to group intelligence(social intelligence), and AI-assisted brain cognitive intelligence.

关键词： artificial intelligence cognitive science brain science intelligence science large language model