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Acta Geochimica 2023年第4期42卷 765-778页

作者： jian-ming gong Qing-song Cheng Chuan-sheng Yang jian-qiang Wang Yong Yuan Qingdao Institute of Marine Geology Qingdao 266071ShandongChina PetroChina Zhejiang Oilfield Company Hangzhou 310023ZhejiangChina

In order to understand the hydrocarbon generation potential of the siliceous shale in the Permian Gufeng Formation of the South Yellow Sea,the organic geochemistry and organic petrology of the siliceous shale in the Gufeng Formation of the CSDP-2 well were studied and *** is found that the TOC of the samples is mainly between 9%and 12%,and Tmaxis mainly distributed between 510 and 540℃.The value of the organic microscopic type index(TI)is between 25.71 and 31.00,which is a set of II_(2)high-quality source rocks with high organic matter abundance in the over mature stage of largescale gas *** to the distribution characteristics of Molecular fossils in siliceous shale of Gufeng Formation of well CSDP-2,bacterial organic matter is the main hydrocarbon generating parent material,and aquatic animal organic matter is an important hydrocarbon generating parent *** siliceous shale in Gufeng Formation of CSDP-2 well is in the stage of large-scale gas generation;Therefore,the Gufeng Formation in the central uplift of the South Yellow Sea has the material basis for the formation of large-scale shale gas *** the same time,the siliceous metasomatism of the siliceous shale reservoir of Gufeng Formation is not conducive to the primary migration of oil,and there is much oil and gas remaining in the reservoir.

关键词： South Yellow Sea Basin Gufeng formation Source rock Molecular geochemistry Shale gas

Gradient Elastic–Plastic Properties of Expanded Austenite Layer in 316L Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 831-841页

作者： Yong jiang Yang Li Yun-Fei Jia Xian-Cheng Zhang jian-ming gong School of Mechanical and Power Engineering Nanjing University of TechnologyNanjing 211816China Key Laboratory of Design and Manufacture of Extreme Pressure Equipment Nanjing 211816Jiangsu ProvinceChina Key Laboratory of Pressure System and Safety MOESchool of Mechanical and Power EngineeringEast China Universityof Science and TechnologyShanghai 200237China

The gradient mechanical properties, variation of stress with strain and surface cracking behavior of expanded austenite developed on 316L austenitic stainless steel were investigated by nanoindentation tests, X-ray residual stress analysis and scanning electron microscope observation in four-point bending tests. The results show that the plastic properties of the carburizing layer including true initial yield strengths and strain hardening exponents increase significantly from substrate to surface, while the true elastic modulus just improves slightly. Due to the onset of plastic flow, the residual stresses are almost equivalent to the true initial yield strengths from surface to the depth of ～10 lm. The results of four-point bending tests show that surface stress increases linearly with the increase in strain until the strain reaches～1.0%, after that the plastic yield happens. The expanded austenite surface layer is brittle, and the cracks will be created at the strain of ～1.4%.The cracking stress is about～2.4 GPa.

关键词： Low-temperature gaseous carburization Expanded austenite Nanoindentation Gradient elastic-plastic properties Four-point bending

Formation of G-phase in 20Cr32Ni1Nb Stainless Steel and its Effect on Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 829-839页

作者： Xiao-Feng Guo Ying-Ying Ni jian-ming gong Lu-Yang Geng jian-Qun Tang Yong jiang Xian-Kai Jia Xin-Yu Yang School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China Key Lab of Design and Manufacture of Extreme Pressure Equipment Nanjing 210037China

A series of tensile tests, Charpy impact tests, optical microscopy observations, and field emission-scanning electron microscopy examinations, were carded out to investigate the mechanical properties and microstructural evolution of 20Cr32NilNb steel. Experimental results indicate that the as-cast microstructure of the steel typically consists of a supersaturated solid solution of austenite matrix with a network of interdendritic primary carbides （NbC and M23C6）. In the ex-service samples, large amounts of secondary carbides precipitate within austenite matrix. Besides the growth and coarsening of NbC and M23C6 carbides during service condition, the Ni-Nb silicides known as G-phase （Nil6Nb6Si7） are formed at the interdendritic boundaries. The microstructural evolution results in the degradation of the mechanical properties of the ex-service steel. In addition, the precipitate rate of G-phase, depending in part on Si content, varies greatly for the 20Cr32NilNb steel, which plays a key role in the long-term microstructural stability of the steel. Based on the X-ray diffraction data, time-temperature-transformation curve for the steel is obtained from the aged specimens.

关键词： 20Cr32NilNb Embrittlement G-phase TTT dial, ram

Exploration prospects of oil and gas in the Northwestern part of the Offshore Indus Basin, Pakistan

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China Geology 2020年第4期3卷 633-642页

作者： jian-ming gong Jing Liao Jie Liang Bao-hua Lei jian-wen Chen Muhammad Khalid Syed Waseem Haider ming Meng Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and TechnologyQingdao 266061China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Pakistan Hydrographic Department 11 Liaquat Barracks Shahrae Faisal KARACHI-75530Pakistan National Institute of Oceanography St-47Block-1CliftonKarachiPakistan School of Ocean Sciences China University of Geosciences(Beijing)Beijing 100083China

Oil and gas resources are short in Pakistan and no commercially viable oil and gas sources have been yet discovered in its offshore areas up to *** this study,the onshore-offshore stratigraphic correlation and seismic data interpretation were conducted to determine the oil and gas resource potential in the Offshore Indus Basin,*** on the comprehensive analysis of the results and previous data,it is considered that the Cretaceous may widely exist and three sets of source rocks may be developed in the Offshore Indus *** presence of Miocene mudstones has been proven by drilling to be high-quality source rocks,while the Cretaceous and Paleocene–Eocene mudstones are potential source ***-lithologic traps are developed in the northwestern part of the basin affected by the strike-slip faults along Murray ***,the Cretaceous and Paleocene–Eocene source rocks are thick and are slightly affected by volcanic ***,it can be inferred that the northwestern part of Offshore Indus Basin enjoys good prospects of oil and gas resources.

关键词： Oil and gas Cretaceous Offshore Indus Basin Oil storage structure Oil and gas engineering Pakistan

Discussion on "sandwich"structures and preservation conditions of shale gas in the South Yellow Sea Basin

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China Geology 2018年第4期1卷 485-492页

作者： jian-qiang Wang jian-ming gong Li Zhang Hai-yan Cheng Jing Liao jian-wen Chen Jing Su Chuan-sheng Yang Qingdao Institute of Marme Geology CGSQingdao 266071China Laboratory for Marme Mineral Resource Qingdao Pilot National Laboratory for Marme Science and TechnologyQingdao 266071China Guangzhou Marine Geological Survey Guangzhou 510760China Qingdao Geological Exploration Institute of China Metallurgical Geology Bureau Qingdao 266071China 不详

In order to make a breakthrough in Mesozoic-Paleozoic shale gas exploration in the South Yellow Sea Basin,a comparison of the preservation conditions was made within the Barnett shale gas reservoirs in the Fortworth Basin,the Jiaoshiba shale gas reservoirs in Sichuan Basin and potential shale gas reservoirs in Guizhou *** results show that the "Sandwich"structure is of great importance for shale gas *** to,the "Sandwich"structure is a kind of special reservoir-cap rock assemblage which consist of limestone or dolomite on the top,mudstone or shale layer in the middle and limestone or dolomite at the *** consideration of the Mesozoic-Paleozoie in the Lower Yangtze,and Laoshan Uplift with weak Paleozoic deformation and thrust fault sealing On both flanks of the Laoshan Uplift,a conclusion can be drawn that the preservation conditions of shale gas probably developed "Sandwich" structures in the Lower Cambrian and Permian,which are key layers for the breakthrough of shale gas in the South Yellow ***,the preferred targets for shale gas drilling probably locate at both flanks of the Laoshan Uplift.

关键词： "Sandwich"structure Preservation conditions Shale gas Laoshan Uplift South Yellow Sea

Exploring a Promising Region and Enhancing Decision Space Diversity for Multimodal Multi-Objective Optimization

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Tsinghua Science and Technology 2024年第2期29卷 325-342页

作者： Fei ming Wenyin gong School of Computer Science China University of GeosciencesWuhan 430074China

During the past decade,research efforts have been gradually directed to the widely existing yet less noticed multimodal multi-objective optimization problems(MMOPs)in the multi-objective optimization ***,researchers have begun to investigate enhancing the decision space diversity and preserving valuable dominated solutions to overcome the shortage caused by a preference for objective space ***,many existing methods still have limitations,such as giving unduly high priorities to convergence and insufficient ability to enhance decision space *** overcome these shortcomings,this article aims to explore a promising region(PR)and enhance the decision space diversity for handling *** traditional methods,we propose the use of non-dominated solutions to determine a limited region in the PR in the decision space,where the Pareto sets(PSs)are included,and explore this region to assist in solving ***,we develop a novel neighbor distance measure that is more suitable for the complex geometry of PSs in the decision space than the crowding *** on the above methods,we propose a novel dual-population-based coevolutionary *** studies on three benchmark test suites demonstrates that our proposed methods can achieve promising performance and versatility on different *** effectiveness of the proposed neighbor distance has also been justified through comparisons with crowding distance methods.

关键词： multimodal multi-objective optimization evolutionary algorithms promising region neighbor distance decision space coevolution

Characteristics of major and trace elements in surface sediments of the Makran Accretionary Prism, Pakistan and their implications for natural gas hydrates

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China Geology 2021年第2期4卷 299-310页

作者： jian-ming gong Jing Liao Yu-xi Zhang Jie Liang jian-wen Chen Nuzhat Khan Syed Waseem Haider Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and TechnologyQingdao 266071China Shandong University of Science and Technology Qingdao 266071China National Institute of Oceanography ST-47Block-1CliftonKarachi-75600Pakistan

To accurately identify the natural gas hydrates(NGH)in the sea area of the Makran Accretionary Prism,Pakistan,this paper presents the testing and analysis of major and trace elements in sediment samples taken from two stations(S2 and S3)in the area by the China Geological *** shown by testing results,all major elements are slightly different in content between the two stations except SiO2 and *** also applies to the trace elements that include Sr and Ba primarily and Cr,Ni and Zn *** can be concluded in this study that the tectonic setting of the Makran Accretionary Prism is dominated by oceanic island arc and that provenance of the Makran Accretionary Prism is dominated by felsic igneous provenance,which is at the initial weathering stage and mainly consists of *** terrigenous detritus,there are sediments possibly originating from Makran-Bela Ophiolite from the northwestern part and Murray Ridge igneous rocks from the southeastern *** V/Cr,Ni/Co,and V/(V+Ni)ratios indicate that sediments of the two stations are in an oxidation-suboxidation ***,the authors infer that the sedimentary environment of the sediments 3.0 m below the seafloor tends to be gradually transformed into a reduction environment by comparison with the Qiongdongnan Basin in the South China Sea where NGH has been *** sediments in the Makran Accretionary Prism are rich in organic matter,with total organic carbon(TOC)content greater than 1%.According to comprehensive research,the organic matter in the sediments mainly originates from marine algae and has high TOC content,which is favorable for the formation of NGH.

关键词： Characteristics of major and trace elements Natural gas hydrates Marine algae Total organic carbon Makran Accretionary Prism NGH exploration trial engineering Arabian Sea Pakistan

Even Search in a Promising Region for Constrained Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 474-486页

作者： Fei ming Wenyin gong Yaochu Jin School of Computer Science China University of GeosciencesWuhan 430074China IEEE Faculty of Technology Bielefeld UniversityNorth Rhine-Westphalia 33619Germany School of Engineering Westlake UniversityHangzhou 310030China

In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However, an overly finetuned strategy or technique might overfit some problem types,resulting in a lack of versatility. In this article, we propose a generic search strategy that performs an even search in a promising region. The promising region, determined by obtained feasible non-dominated solutions, possesses two general ***, the constrained Pareto front(CPF) is included in the promising region. Second, as the number of feasible solutions increases or the convergence performance(i.e., approximation to the CPF) of these solutions improves, the promising region shrinks. Then we develop a new strategy named even search,which utilizes the non-dominated solutions to accelerate convergence and escape from local optima, and the feasible solutions under a constraint relaxation condition to exploit and detect feasible regions. Finally, a diversity measure is adopted to make sure that the individuals in the population evenly cover the valuable areas in the promising region. Experimental results on 45 instances from four benchmark test suites and 14 real-world CMOPs have demonstrated that searching evenly in the promising region can achieve competitive performance and excellent versatility compared to 11 most state-of-the-art methods tailored for CMOPs.

关键词： Constrained multi-objective optimization even search evolutionary algorithms promising region real-world problems

Optimizing magnetoelastic properties by machine learning and high-throughput micromagnetic simulation

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Rare Metals 2024年第5期43卷 2251-2262页

作者： jian-Hu gong Zheng-ming Zhang Cheng-Liang Zhang Peng-Qiang Hu Chao Zhou Dun-Hui Wang Sen Yang Division of Microelectronic Materials and Devices Hangzhou Dianzi UniversityHangzhou 310018China School of Physics MOEKey Laboratory forNonequilibrium Synthesis and Modulation of Condensed Matter and State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China

Magnetoelastic couplings in giant magnetostrictive materials(GMMs)attract significant interests due to their extensive applications in the fields of spintronics and energy harvesting *** the role of the selection of materials and the response to external fields is essential for attaining desired functionality of a ***,machine learning(ML)models are conducted to predict saturation magnetostrictions(λ_(s))in RFe_(2)-type(R=rare earth)GMMs with different *** to ML-predicted composition–λsrelations,it is discovered that the values ofλshigher than1100×10^(-6)are almost situated in the composition space surrounded by 0.26≤x≤0.60 and 1.90≤y≤2.00 for the ternary compounds of Tb_(x)Dy_(1-x)Fe_(y).Assisted by ML predictions,the compositions are further narrowed down to the space surrounded by 0.26≤x≤0.32 and 1.92≤y≤1.97 for the excellent piezomagnetic(PM)performance in the Tb_(x)Dy_(1-x)Fe_(y)based PM device through our developed high-throughput(HTP)micromagnetic simulation(MMS)***,high sensitivities up to10.22-13.61 m T·MPa^(-1)are observed in the optimized range within which the available experimental data fall *** work not only provides valuable insights toward understanding the mechanism of magnetoelastic couplings,but also paves the way for designing and optimizing highperformance magnetostrictive materials and PM sensing devices.

关键词： Magnetostriction Piezomagnetic effect Machine learning Micromagnetic simulation

Applications of mercury stable isotopes for tracing volcanism in the geologic record

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Science China Earth Sciences 2024年第5期67卷 1436-1458页

作者： Qing gong ming-Xing LING Wang ZHENG State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth System Science Institute of Surface-Earth System ScienceTianjin UniversityTianjin 300072China

Mercury(Hg)enrichments in ancient sediments have been used as a proxy of volcanism,especially large igneous province(LIP)***,considering the existence of other potential Hg sources besides volcanoes and the diverse factors(e.g.,organic matters,clay minerals,sulfide minerals and Fe oxides)that can affect Hg sequestration,there are considerable uncertainties to simply regard sedimentary Hg anomalies as signatures of volcanic *** stable isotopes,a promising tool for tracing the origins and transformations of Hg,have been increasingly used for determining the causes of Hg spikes and understanding the geochemical behavior of Hg in the geologic *** date,lots of researches have applied Hg concentrations and Hg isotopes to identify LIP volcanisms linking with significant geological events such as mass extinctions,ocean anoxic events and other environmental perturbations that mainly occurred in the ***,the results in previous studies clearly show that not all Hg enrichments are derived from volcanic inputs,which emphasize the need for more caution in using Hg as a fingerprint of *** a better understanding of Hg isotopes in the future,there will be important implications for Hg isotopes to reconstruct volcanic activities in the rock records and their impacts on biological evolution.

关键词： Mercury stable isotopes Large igneous province Mass extinction event Ocean anoxic event