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Lithology Classification Based on Set-Valued Identification Method

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Journal of Systems Science & Complexity 2022年第5期35卷 1637-1652页

作者： LI Jing WU Lifang LU Wenjun WANG Ting kang Yu feng Deyong ZHOU Hansheng Department of Automation University of Science and Technology of ChinaHefei 230027China Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China Shengli Geophysical Research Institute SINOPEC GroupDongying 257022China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China

Lithology classification using well logs plays a key role in reservoir *** paper studies the problem of lithology identification based on the set-valued method(SV),which uses the SV model to establish the relation between logging data and lithologic types at a certain depth *** particular,the system model is built on the assumption that the noise between logging data and lithologic types is normally distributed,and then the system parameters are estimated by SV method based on the existing identification *** logging data of Shengli Oilfield in Jiyang Depression are used to verify the effectiveness of SV *** results indicate that the SV model classifies lithology more accurately than the Logistic Regression model(LR)and more stably than uninterpretable models on imbalanced ***,the Macro-F1 of the SV models(i.e.,SV(3),SV(5),and SV(7))are higher than 85%,where the sandstone samples account for only 22%.In addition,the SV(7)lithology identification system achieves the best stability,which is of great practical significance to reservoir exploration.

关键词： DT lithology classification LR RF set-valued model SVM

Mechanistic study of ammonium-induced corrosion of AZ31 magnesium alloy in sulfate solution

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Journal of Materials Science & Technology 2020年第19期54卷 1-13页

作者： Hui Pan Liwei Wang Yi Lin feng Ge kang Zhao Xin Wang Zhongyu Cui College of Electromechanical Engineering Qingdao UniversityQingdao 266071China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

The influence of NH4+ions on the corrosion behavior of AZ31 magnesium alloy was investigated by immersion test,hydrogen evolution,electrochemical methods and morphology *** results demonstrate the acceleration effect of NH4+on corrosion of AZ31 magnesium alloy due to the disruption of protective MgO film in NH4+-containing *** loose and cracked corrosion products of AZ31 magnesium alloy in NH4+-containing solutions are mainly composed of(Mg0.833Al0.167)(OH)2(CO3)0.083·0.75H2O and Mg5(CO3)4(OH)2·*** the NH4+concentration is lower than 0.01 M,knife-cut like corrosion occurs in some active area of the surface due to the partial dissolution of MgO *** the NH4+concentration is increased to 0.1 M,the MgO layer is completely disrupted,resulting in the occurrence of uniform *** cathodic and anodic reactions are accelerated by NH4+ions,while the effect of original pH values on the reaction kinetics can be neglected in NH4+-containing solutions.

关键词： Magnesium alloy Ammonium Corrosion kinetics Knife-cut like corrosion

Application of a new basalt fiber-reinforced polymer anchorage structure in the tunnel–slope system under rainfall action

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Journal of Mountain Science 2023年第2期20卷 570-584页

作者： TANG Lin WU Hong-gang WEI Hong feng kang RENG Guo-jun College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China China Northwest Research Institute Co.Ltd.of CREC Lanzhou 730070China College of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyang 621000China

The application of basalt fiber-reinforced polymer(BFRP)anchors has gained significant attention,particularly in the field of geotechnical anchorage engineering because of its high strength and corrosion *** research on the applicability of BFRP anchor in a tunnel–slope system under rainfall is of practical significance to solve the problem of instability damage to anchored slopes caused by corrosion of steel *** this study,model tests of BFRP and steel anchorage structures were conducted to compare their reinforcement capability in a tunnel–slope system under heavy *** results show that the BFRP anchorage structure is better than the steel in coordinating slope deformation and stabilizing earth pressure around the *** deformation of slopes under rainfall is classified into four stages:initial,isokinetic,accelerated,and blocked *** anchors have the same axial strain distribution pattern as the steel anchors,and they are convexly distributed along the axial direction of the *** correlation analysis and Pearson linear correlation analysis of the multi-attribute data of the slope and BFRP anchors showed a positive correlation among BFRP anchor strain,earth pressure inside the slope,slope deformation displacement,and accumulated *** research results provide a basis and reference for the application of BFRP anchors in the anchorage engineering of the tunnel–slope system under rainfall action.

关键词： BFRP anchors Steel anchors Rainfall Tunnel-slope system

Bioactive calcium and mangnesium phosphate bone adhesive for enhanced vascularization and bone regeneration

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Journal of Materials Science & Technology 2023年第33期164卷 246-257页

作者： Jiawei Liu Honglei kang Wenying Wei Rong Tu Takashi Goto feng Li Honglian Dai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Biomedical Materials and Engineering Research Center of Hubei ProvinceWuhan University of TechnologyWuhan 430070China Department of Orthopedics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Chaozhou Branch of Chemistry and Chemical Engineering Guangdong Laboratory Chaozhou 521000China New Industry Creation Hatchery Center Tohoku UniversitySendai 980-8579Japan

Bone adhesive is a promising material for the treatment of bone fractures,which is helpful for the fast and effective reduction and fixation of broken ***,the existing adhesives bond weakly to bone tissues,and are non-absorbable,or hard to cure under wet ***,inspired by the cement-based adhesive used in the industry field,we report a bioactive calcium and magnesium phosphate bone adhesive(MPBA)with the properties of facile preparation,robust adhesion,and *** is equipped with similar strength to cancellous bones and shows reliable bonding performance for various interfaces,such as Ti6Al4V,Al2O3,and poly(ether-ether-ketone).MPBA achieves excellent bonding ability for the above interfaces with the bonding strengths of 2.28±0.47,2.32±0.15,and 1.44±0.38 MPa,***,it also shows reliable fixation ability for bovine bone *** bonding behavior to materials and bones suggests that MPBA could be used for both fracture treatment and implant ***,MPBA possesses good biological activity,which could promote the vascularization process and osteogenic ***,in vivo experiments confirmed MPBA can effectively restore bone strength and promote bone regeneration.

关键词： Fracture Calcium magnesium phosphate cement Bone adhesives

Effects of cooling rate on the microstructure and properties of magnesium alloy-a review

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Journal of Magnesium and Alloys 2024年第8期12卷 3094-3114页

作者： Huisheng Cai Nannan Zhang Liang Liu Juan Su Yuguang Li Yu kang feng Guo Inner Mongolia Key Laboratory of Thin Film and Coatings School of Material Science and EngineeringInner Mongolia University of TechnologyHohhot 010051China School of Sino-German Engineering Shanghai Technical Institute of Electronics and InformationShanghai 201411China

Magnesium alloy is one of the most widely used lightweight structural materials,and the development of high strength-toughness magnesium alloy is an important research field at present and even in the *** preparation process parameters of magnesium alloy directly affect the microstructure of the magnesium alloy,and then determine the properties of the magnesium *** cooling rate has important effects on the microstructure and properties of the magnesium alloy,and is an important preparation process parameter that cannot be *** the cooling rate from liquid phase to solid phase and the cooling rate of the magnesium alloy after heat treatment will change the microstructure of the magnesium ***,the properties of magnesium alloy will be *** this paper,the effects of cooling rate on the solidification behavior,the rheological behavior,the change of microstructure(the solid solution of alloying elements in matrix,the composition,size,distribution and morphology of second phase,the diffusion and segregation of alloying elements,the grain size,the formation and morphology of dendrite,etc.),and the effects of cooling rate of magnesium alloy after heat treatment on the microstructure and stress distribution are *** reasons for the divergence about the influence of cooling rate on the microstructure of magnesium alloy are analyzed in *** effects of cooling rate on the mechanical properties,corrosion resistance and oxidation resistance of magnesium alloy are also analyzed and discussed ***,the new methods and approaches to study the effects of cooling rate on the microstructure and properties of magnesium alloy are prospected.

关键词： Magnesium alloy Cooling rate Microstructure Mechanical properties Corrosion resistance Oxidation resistance

Design and Development of Highly Efficient Ni/ZnO Catalysts Based on Semiconductor Metal Oxide Catalysis Theory

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China Petroleum Processing & Petrochemical Technology 2023年第2期25卷 33-40页

作者： Bian Yankun kang Lei Wu feng Wang Haiyan Bai Yingzhi Sun Na School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun 113001China China Huanqiu Contracting&Engineer(Lanzhou)Co. Ltd.Beijing 100029China

In the context of reactive adsorption desulfurization,the development of an efficient Ni/ZnO desulfurizer has attracted increasing *** the work reported here,a novel Ni/Mn-ZnO composite nanowire desulfurizer is designed on the basis of the catalytic theory of semiconductor metal oxides and the characteristics of one-dimensional nanomaterials.X-ray diffraction,scanning electron microscopy,N_(2) adsorption-desorption,and X-ray photoemission spectroscopy demonstrate that Mn doping changes the crystal structure and morphology of the Ni/ZnO desulfurizer,increases the number of quasi-free electrons in the ZnO,and promotes H_(2)S *** Ni/Mn-ZnO composite nanowire desulfurizer exhibits good desulfurization performance when used with gasoline as the raw material.

关键词： Ni/ZnO nanowire Mn desulfurization

Q-switched and mode-locked Er-doped fiber laser using PtSe2 as a saturable absorber

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Photonics Research 2018年第9期6卷 893-899页

作者： kang ZHANG MING feng YANGYANG REN FANG LIu XINGSHUO CHEN JIE YANG XIAO-QING VAN feng SONG JIANGUO TIAN Key Laboratory of Weak-Light Nonlinear Photonics Ministry of EducationSchool of Physics and TEDA Applied Physics SchoolNankai UniversityTianjin 300071China

We report a passively Q-switched and mode-locked erbium-doped fiber laser(EDFL) based on PtSe_2, a new two-dimensional material, as a saturable absorber(SA). Self-started Q-switching at 1560 nm in the EDFL was achieved at a threshold pump power of 65 mW, and at the maximum pump power of 450 m W, the maximum single Q-switched pulse energy is 143.2 n J. Due to the polarization-dependent characteristics of the PtSe_2-based SA, the laser can be switched from the Q-switched state to the mode-locked state by adjusting the polarization state. A mode-locked pulse train with a repetition rate of 23.3 MHz and a pulse width of 1.02 ps can be generated when the pump power increases to about 80 m W, and the stable mode-locked state is maintained until the pump power reaches its maximum 450 m W. The maximum single mode-locked pulse energy is0.53 nJ. This is the first time to our knowledge that successful generation of stable Q-switched and mode-locked pulses in an Er-doped fiber laser has been obtained by using PtSe_2 as a saturable absorber.

关键词：二维材光纤激光器通讯技术发展现状

Frequency stabilization in FBG external cavity semiconductor laser based on acetylene absorption method

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Optoelectronics Letters 2008年第5期4卷 335-338页

作者： Li Zhi-quan Su feng-yan kang Li-li College of Electrical Engineering Yanshan University Qinhuangdao 066004 China

A frequency-stabilized 1.53 μm FBG external-cavity semiconductor laser by using acetylene absorption is presented and its basic principles are introduced. Graded refractive index fiber and pigtailed fiber are used in the absorption air chamber to enhance the coupling stability. The impact of the background power is eliminated by using the third-harmonic mode-locking technique. A lock-in amplifier is utilized to ensure that the output laser wavelength is locked at the C2H2 absorption line of 1530.37 nm. The frequency stability reaches 10-8 within 24 h.

关键词：稳频激光器半导体乙炔吸收

Provenance Study of Fe–Ti Oxide Minerals in the Quaternary Sediments in Yichang Area and Its Implication of Formation Time of the Yangtze Three Gorges, China

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1598-1608页

作者： XIANG Fang DU Wen HUANG Henxu kang Dongya ZHU Hongbo feng Qin State Key Laboratory of Oil and Gas reservoir Geology and exploitation Chengdu University of Technology Shangdong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Mineral Shangdong University of Science and Technology Institute of sedimentary geology Chengdu University of Technology

The Three Gorges are considered to be critical to understand the formation of Yangtze River. Recent research results suggest that the Yangtze Three Gorges was created during the Quaternary but the exact time is debatable. Fe-Ti oxide minerals are seldom used to study sediment provenance, expecially using scanning electron microscopy （SEM）, and energy dispersive spectrometer （EDS）. In this study, the provenance of Quaternary sediments in Yichang area, which is located to the east of the Yangtze Three Gorges, was investigated by using SEM and EDS to research Fe-Ti oxides. The Panzhihua vanadium titanomagnetite and Emeishan basalt outcrop are located to the west of the Three Gorges. Further, the materials from them are observed in the Quaternary sediments of Yichang area. Fe-Ti oxide minerals from the Huangling granite are observed in the Yunchi and Shanxiyao Formations, which were formed before 0.75 Ma B.P., whereas Fe-Ti oxide minerals from the Huangling granite, Panzhihua vanadium titanomagnetite, and Emeishan basalt are observed in the riverbed and fifth-terrace sediments of the Yangtze River, which were formed after 0.73 Ma B.P.. Thus, we can infer that the Three Gorges formed after the deposition of the Shanxi Formation and before the fifth-terrace; i.e., 0.75-0.73 Ma B.P..

关键词： Yangtze Three Gorges Yichang area Quaternary sediments Fe-Ti oxide minerals China