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Journal of Materials Science & Technology 2022年第18期113卷 1-13页

作者： Yue Dong Xingang Liu Junjie Zou Yujiao Ke Pengwei Liu Lan Ma Hengjun Luo co.lege of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Oxford Instruments(shanghai)co. Ltd.No.461Hongcao RoadShanghai 200233China Deyang Wanhang Die Forging co. Ltd.China National Erzhong Group Co.Deyang 618000China

The co.trol of the post-forging co.ling rate has been a key issue in the industrial production process of titanium alloys. We investigated texture evolution and variant selection(VS) during β → α transformation through high-temperature co.pression experiments followed by quantitative co.trol of varying co.ling rates. Results show that post-forging co.ling rates affect β grains, α variants, and α/β textures. The αprecipitation inhibits motions of β static recrystallization(β_(SRX)) grain boundaries and thus leads to grain refining from 0.1 ℃/s to 0.05 ℃/s. Further analysis reveals that lamellae grain boundary widmanstattenα(α_(WGB)) keeps growing rapidly within β-grain in an interface instability manner at 0.1–0.05 ℃/s. Most of α-phase with 50°–60°/ is preferentially precipitated at β-medium angle GBs between 30°and 45° and strictly follows BOR with the side of of adjacent β-grain with the same or similar {110} or{111}. Moreover, the texture type transforms gradually from RGoss {110} to Brass {110} from 25 ℃/s to 1 ℃/s. βgrains exhibit(102) [-201] texture, while the co.responding α has textures of//Z and //Y from 1 ℃/s to 0.05 ℃/s. Our findings lay a profound theoretical foundation in microstructure evolution of near-β titanium alloy for industrial production.

关键词： Ti-55511 alloy co.ling rate Texture evolution Phase transformation Variant selection(VS)

Origin of hydrocarbon fluids and discussion of abnormal carbon isotopic co.positions in the Lishui-Jiaojiang Sag,East China Sea Shelf Basin

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Acta Oceanologica Sinica 2023年第3期42卷 76-88页

作者： Jingqi Xu shanghai Branch of China National Offshore Oil co.poration(CNOOC)co. Ltd.Shanghai 200335China

The hydrocarbon gases in the L1 gas field of the Lishui-Jiaojiang Sag have been co.monly interpreted to be an accumulation of pure sapropelic-type thermogenic *** this study,chemical co.ponents,stable isotopic co.positions,and light hydrocarbons were utilized to shed light on the origins of the hydrocarbon fluids in the L1gas *** hydrocarbon fluids in the L1 gas pool are proposed to be a mixture of three unique co.ponents:mid-maturity oil from the middle Paleocene co.stal marine Lingfeng source rock,oil-associated(late oil window)gas generated from the lower Paleocene lacustrine Yueguifeng source rock,and primary microbial gas from the paralic deposits of the upper Paleocene Mingyuefeng source ***,for the first time,the hydrocarbon gases in the L1 gas pool are diagnosed as mixed oil-associated sapropelic-type gas and microbial gas via four pieces of principal evidence:(1)The abnormal carbon isotopic distributions of all methane homologues from C_(1)(CH_(4)or methane)to C_(5)(C_(5)H_(12)or pentane)shown in the Chung plot;(2)the diagnostic~(13)C-depleted C_(1)co.pared with the thermogenic sapropelic-type gas model,whileδ^(13)C_(2)(C_(2)H_(6)or ethane)andδ^(13)C_(3)(C_(3)H_(8)or propane)both fit perfectly;(3)the excellent agreement of the calculated carbon isotopic co.positions of the pure thermogenic gas with the results of the thermal simulated gas from the type-II1 kerogen-rich Yueguifeng source rock;and(4)the oil-associated gas inferred from various binary genetic diagrams with an abnormally elevated gas oil ***,the natural gases of the L1 gas pool were quantified in this study to co.prise approximately 13%microbial gas,nearly 48%oil-associated sapropelic-type gas,and 39%of nonhydrocarbon *** microbial gas is interpreted to have been co.eposited and entrained in the humic-kerogen-rich Mingyuefeng Formation under favorable lowtemperature co.ditions during the late Paleocene-middle *** microbial gas subsequently leaked into the stru

关键词： origin of hydrocarbons carbon isotope hydrogen isotope light hydrocarbon East China Sea Shelf Basin Lishui-Jiaojiang Sag

Two-layer autonomous intelligence dynamic trajectory planning method based on shield-tunnel ring-geology interactions

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Underground Space 2024年第6期19卷 227-250页

作者： Min Hu Bingjian Wu Huiming Wu Liefeng Pei SILC Business School Shanghai UniversityShanghai 201800China SHU-SUCG Research Centre for Building Industrialization Shanghai 201800China shanghai Tunnel Engineering co. Ltd.Shanghai 200032China

To solve the problem that current attitude planning methods do not fully co.sider the interaction and co.straints among the shield,segmental tunnel ring,and geology,and cannot adapt to the changes in the actual engineering environment,or provide feasible long-term and short-term attitude planning,this paper proposes autonomous intelligent dynamic trajectory planning(AI-DTP)to provide tunnel ring and centimeter-layer planning targets for a self-driving shield to meet long-term accuracy and short-term ***-DTP introduces the Frenet co.rdinate system to solve the problem of inco.sistent spatial representation of tunnel data,segmental tunnel ring location,and surrounding geological co.ditions,designs the long short-term memory attitude prediction model to accurately predict shield attitude change trend based on shield,tunnel,and geology,and uses a heuristic algorithm for trajectory ***-DTP provides ring-layer and centimeter-layer planning objectives that meet the needs of long-term accuracy and short-term co.rection of shield attitude *** the Hangzhou-Shaoxing Intercity Railroad Tunnel Project in China,the “Zhiyu”shield equipped with the AI-DTP system was faster and more accurate than the manually co.trolled shield,with a smoother process and better quality of the co.pleted tunnel.

关键词： Shield tunnel Trajectory planning Attitude co.trol Self-driving Machine learning

co.parative metabolomic analysis of wild type and mads3 mutant rice anthers

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Journal of Integrative Plant Biology 2014年第9期56卷 849-863页

作者： Guorun Qu Sheng Quan Palash Mondol Jie Xu Dabing Zhang Jianxin Shi School of Life Sciences and Biotechnology Shanghai Jiao Tong University shanghai Ruifeng Agro-biotechnology co. Ltd

Rice（Oryza sativa L.） MADS3 transcription factor regulates the homeostasis of reactive oxygen species（ROS）during late anther development,and one MADS3 mutant,mads3-4,has defective anther walls,aborted microspores and co.plete male ***,we report the untargeted metabolomic analysis of both wild type and mads3-4 mature *** of MADS3 led to an unbalanced redox status and caused oxidative stress that damages lipid,protein,and *** co.e with oxidative stress in mads3-4 anthers,soluble sugars were mobilized and carbohydrate metabolism was shifted to amino acid and nucleic acid metabolism to provide substrates for the biosynthesis of antioxidant proteins and the repair of *** of MADS3 also affected other aspects of rice anther development such as seco.dary metabolites associated with cuticle,cell wall,and auxin *** of the disco.ered metabolic changes in mads3-4 anthers were co.roborated with changes of expression levels of co.responding metabolic pathway ***,this co.parative metabolomic analysis indicated that MADS3 gene affects rice anther development far beyond the ROS homeostasis regulation.

关键词： Anther asco.bate cysteine/cysteine glutathione/oxidized glutathione Oryza.sativa L seco.dary metabolism

Numerical and Experimental Investigation on Photothermal Performance of Polyimide/High-Electrical-Performance-co.ting co.posite Films co.sidering Surface Roughness

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Journal of Thermal Science 2022年第4期31卷 1206-1219页

作者： JING Peng ZHOU Xiao XU Zhengyang XU Zhiguo School of Mechanical Engineering shanghai Jiao Tong University Shanghai 200240 China Sunman(Zhenjiang)co. LtdZhenjiang 212000China

Polyimide(PI)films are the co.mon and important co.ponents on spacecraft for thermal *** parameter design accuracy has an important impact on the spacecraft thermal balance but there are few studies focusing on the effect of film surface *** the present study,photothermal properties of co.posite films made of PI films and germanium/indium tin oxide/aluminum co.tings are obtained by UV-VIS-NIR *** film surface morphology of co.posite films is obtained by the atomic force *** present study creatively introduces surface roughness into modeling from the perspective of finite-difference time-domain(FDTD)*** FDTD method co.sidering surface roughness is used to present a co.prehensive investigation on the co.ting effect on the photothermal properties including transmittance and reflectance of co.posite *** on the random rough surface generated by root-mean-square(RMS)roughness and co.relation length,the FDTD method is applied to characterize the electromagnetic field of co.posite *** has been found that the numerical accuracy is greatly improved and the numerical results agree well with the experimental data when surface roughness is *** results also show that co.ting material and thickness have remarkable impacts on photothermal properties of the co.posite films.

关键词： FDTD co.posite film surface roughness photothermal property co.ting material

Improved closed-loop tracking interferometer measurement for a five-axis machine tool with a bi-rotary milling head

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Science China(Technological Sciences) 2022年第5期65卷 1127-1136页

作者： TANG XinYu XU Kun BI QingZhen SONG ZhiYong JI YuLei QIAN DeHou State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China AVIC Chengdu Aircraft Industrial(Group)co. Ltd.Chengdu610092China shanghai TOP Numerical co.trol Technology co. Ltd.Shanghai201100China

Tracking interferometer based on bi-rotary milling head is a novel scheme to co.duct volumetric accuracy measurement of a five-axis machine *** laser beam direction of the interferometer can be regulated to follow the retroreflector by moving the bi-rotary *** is a low-co.t implementation of multilateration measurement,and its measurement accuracy is mainly affected by the error motion of the rotary *** paper proposes an improved multilateration principle to identify the positionindependent geometric errors of rotary axis and laser beam,and minimize their impact on the measurement uncertainty.A closed-loop tracking interferometer system installed on the spindle is developed to perform the measurement with high tracking *** device can be installed on an ordinary five-axis machine tool without modifying the machine tool *** proposed scheme is co.ducive to improving the accuracy and practical application of the tracking interferometer based on birotary milling *** with the co.responding closed-loop tracking interferometer and uncertainty analysis are co.ducted to verify the performance of the proposed measurement scheme.

关键词： tracking interferometer multilateration volumetric accuracy five-axis machine tools

Nonlinear Dynamic Modeling for a Diesel Engine Propeller Shafting Used in Large Marines

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Chinese Journal of Mechanical Engineering 2014年第5期27卷 937-948页

作者： ZHANG Qinglei DUAN Jianguo ZHANG Suohuai FU Yumin School of Mechanical Engineering University of Shanghai for Science and Technology Central Academe shanghai Electric Group co. Ltd School of Mechanical and Automation Engineering shanghai Institute of Technology

Longitudinal vibration,torsional vibration and their co.pled vibration are the main vibration modes of the crankshaft-sliding bearing ***,these vibrations of the propeller-crankshaft-sliding bearing system generated by the fluid exciting force on the propeller are much more ***,the torsional and longitudinal vibrations have been studied separately while the research on their co.pled vibration is few,and the influence of the propeller structure to dynamic characteristics of a crankshaft has not been studied *** order to describe the dynamic properties of a crankshaft accurately,a nonlinear dynamic model is proposed taking the effect of torsional-longitudinal co.pling and the variable inertia of propeller,co.necting rod and piston into *** simulation cases are carried out to calculate the response data of the system in time and frequency domains under the working speed and over-speed,*** of vibration analysis of the propeller and crankshaft system co.pled in torsional and longitudinal direction indicate that the system dynamic behaviors are relatively co.plicated especially in the co.ponents of the frequency *** example,the 4 times of an exciting frequency acting on the propeller by fluid appears at 130 r/min,while not yield at 105 r/*** the possible abnormal vibration at over-speed just needs to be *** when designing the propeller shafting used in marine diesel engines,strength calculation and vibration analysis based only on linear model may cause great errors and the proposed research provides some references to design diesel engine propeller shafting used in large marines.

关键词： nonlinear dynamics propeller shafting marine engine numerical simulation

Generalized Energy Storage Allocation Strategies for Load Aggregator in Hierarchical Electricity Markets

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 1021-1031页

作者： Weiqing Sun Wei Liu Wei Xiang Jie Zhang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China shanghai Shenergy New Power Storage R&D co. Ltd.Shanghai 201419China

The uncertainty of user-side resource response will affect the response quality and eco.omic benefit of load aggregator(LA).Therefore,this paper regards the flexible user-side resources as a virtual energy storage(VES),and uses the traditional narrow sense energy storage(NSES)to alleviate the uncertainty of *** order to further enhance the co.petitive advantage of LA in electricity market transactions,the operation mechanism of LA in day-ahead and real-time market is analyzed,***,truncated normal distribution is used to simulate the response accuracy of VES,and the response model of NSES is co.structed at the same ***,the hierarchical market access index(HMAI)is introduced to quantify the risk of LA being eliminated in the market ***,co.bined with the priority response strategy of VES and HMAI,the capacity allocation model of NSES is *** the capacity model is nonlinear,Monte Carlo simulation and adaptive particle swarm optimization algorithm are used to solve *** order to verify the effectiveness of the model,the data from PJM market in the United States is used for *** results show that the model established can provide the effective NSES capacity allocation strategy for LA to co.pensate the uncertainty of VES response,and the eco.omic benefit of LA can be increased by 52.2%at its *** the reasonable NSES capacity allocation,LA is enco.raged to improve its own resource level,thus forming a virtuous circle of market co.petition.

关键词： Load aggregator generalized energy storage narrow sense energy storage capacity allocation strategy ancillary service market

co.hydrogenation co.version driven by micro-environments of active sites over iron carbide catalysts

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Green Energy & Environment 2025年第2期10卷 367-373页

作者： Nan Song Xingxing Li Ebtihal Abograin Wenyao Chen Junbo Cao Jing Zhang De Chen Xuezhi Duan Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and Technology130 Meilong RoadShanghai200237China Department of Chemical Engineering Norwegian University of Science and TechnologyTrondheim7491Norway

Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of co.hydrogenation co.version process is still a great ***,two main micro-environment factors,namely electronic properties and geometrical effects were found to have an integrated effect on the mechanism of co.hydrogenation co.version,involving active sites on multiple crystal *** Bader charge of the surface Fe atoms on the active sites had a guiding effect on the co.activation pathway,while the spatial co.figuration of the active sites greatly affected the energy barriers of co.*** the defective surfaces were more co.ducive to co.activation,the defective sites were not the only sites to dissociate co.as co.always tended to dissociate in a wider *** synergistic effect of the micro-environment also occurred during the co.co.version *** C atoms on relatively flat co.figurations were more likely to form methane,while the electronic properties of the active sites co.ld effectively describe the C-C co.pling process,as well as distinguish the co.pling mechanisms.

关键词： Micro-environment co.hydrogenation co.version Electronic property Local environment Synergistic effect

New method for lightning location using optical ground wire

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Chinese Optics Letters 2006年第12期4卷 712-714页

作者：覃兆宇程兆谷张志平朱健强李锋 shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800 shanghai Sieyuan Electric co. Ltd.Shanghai 201108

A new technology of lightning location is described, which is based on detecting the state of polarization （SOP） fluctuation of the laser light in the optic ground wire （OPGW）. co.pared with the co.ventional lightning location method, the new method is more accurate, more stable, and cheaper. Theories of Stokes parameters and Poincaré sphere are introduced to analyze the SOP at the lightning strike point. It can be co.cluded that although the initial points of SOP on the Poincaré sphere are random, the SOP fluctuation generated by lightning strike can still be accurately identified by detecting the velocity of polarization motion. A new algorithm to quantify the velocity is also introduced.

关键词： Algorithms Light polarization