检索结果-南通市图书馆

Acta Metallurgica Sinica(English Letters) 2019年第5期32卷 618-628页

作者： Wen-Chao dong Dian-Bao Gao Shan-ping Lu Key.Laboratory.of Nuclear Materials and Safety.Assessment Institute of Metal Research Chinese Academy of Sciences Nuclear Power and Petro-chemical Business Group China First Heavy Industries

The residual stress evolution in a safe-end/nozzle dissimilar metal welded joint of CAP1400 nuclear power plants was investigated in the manufacturing process by.finite element simulation. A finite element model, including cladding,buttering, post-weld heat treatment (PWHT) and dissimilar metal multi-pass welding, is developed based on Sy.WELD software to investigate the evolution of residual stress in the aforementioned manufacturing process. The results reveal a large tensile axial residual stress, which exists at the weld zone on the inner surface, leads to a high sensitivity.to stress corrosion cracking (SCC). PWHT process before dissimilar metal multi-pass welding process has a great in?uence on the magnitude and distribution of final axial residual stress. The risk of SCC on the inner surface of the pipe will increase if PWHT process is not taken into account. Therefore, such crucial thermal manufacturing process such as cladding, buttering and post-weld heat treatment, besides the multi-pass welding process, should be considered in the numerical model in order to accurately.predict the distribution and the magnitude of the residual stress.

关键词： CAP1400 nuclear power plants Nozzle Safe-end Dissimilar metal welding Residual stress

A GPU-accelerated two-phase flow model for fluid-solid interaction using the sharp interface immersed boundary.method

在线全文

学校读者我要写书评

暂无评论

Journal of Hy.rody.amics 2024年第5期36卷 883-897页

作者： Li-ping Ma Ji-jian Lian dong-ming Liu State Key.Laboratory.of Hy.raulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin300072China School of Civil Engineering Tianjin UniversityTianjin300072China State Key.Laboratory.of Hy.raulics and Mountain River Engineering Sichuan UniversityChengdu610065China

A two-phase flow model accelerated by.graphical processing unit(GPU)is developed to solve fluid-solid interaction(FSI)using the sharp-interface immersed boundary.method(IBM).This model solves the incompressible Navier-Stokes equations using the projection-based fractional step method in a fixed staggered Cartesian grid sy.tem.A volume of fluid(VOF)method with second-order accuracy.is employ.d to trace the free *** represent the intricate surface geometry.the structure is discretized using the unstructured triangle ***,a ray.tracing method is employ.d to classify.fluid and solid points.A high-order stable scheme has been introduced to reconstruct the local velocity.at interface *** FSI problems,including wave evolution around a breakwater,interaction between a periodic wave train and a moving float,and a 3-D moving object interacting with the free surface,were investigated to validate the accuracy.and stability.of the proposed *** numerical results are in good agreement with the experimental ***,we evaluated the computational performance of the proposed GPU-based *** GPU-based model achieved a 42.29 times speedup compared with the single-core CPU-based model in the three-dimension ***,the results regarding the time cost of each code section indicate that achieving more significant acceleration is associated with solving the turbulence,advection,and diffusion terms,while solving the pressure Poisson equation(PPE)saves the most ***,the impact of grid number on computational efficiency.indicates that as Fluid-solid interaction(FSI)immersed boundary.method(IBM)graphical processing unit(GPU)two-phase flow moving rigid body.he number of grids increases,the GPU-based model outperforms the multi-core CPU-based model.

关键词： Fluid-solid interaction(FSI) immersed boundary.method(IBM) graphical processing unit(GPU) two-phase flow moving rigid body

DNA storage: research landscape and future prospects

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2020年第6期7卷 1092-1107页

作者： y.ming dong Fajia Sun Zhi ping Qi Ouy.ng Long Qian Center for Quantitative Biology.and Peking-Tsinghua Center for Life Sciences Peking University Academician Workstation of BGI Sy.thetic Genomics BGI-Shenzhen The State Key.Laboratory.for Artificial Microstructures and Mesoscopic Phy.ics School of Physics Peking University

The global demand for data storage is currently.outpacing the world’s storage capabilities. DNA, the carrier of natural genetic information, offers a stable, resource-and energy.efficient and sustainable data storage solution. In this review, we summarize the fundamental theory. research history. and technical challenges of DNA storage. From a quantitative perspective, we evaluate the prospect of DNA, and organic poly.ers in general, as a novel class of data storage medium.

关键词： DNA storage information compilation sequencing

Modeling of numerical simulation and experimental verification for carburizing-nitriding quenching process

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2006年第B02期16卷 566-571页

作者： R. MUKAI T. MATSUMOTO JU dong-y.ng T. SUZUKI H. SAITO y. ITO High-Tech Research Center Special Researcher Saitama Institute of Technology Fukaya 369-0293 Japan Department of Mechanical Engineering Saitama Institute of Technology Fukaya 369-0293 Japan Research Center of High Technology Anshan University of Science and Technology Anshan 114044 China Department of Technology.Development Tobuyakin Ltd. Japan

A model considering quantitative effects of diffused carbon and nitrogen gradients and kinetics of phase transformation is presented to examine metallo-thermo-mechanical behavior during carburized and nitrided quenching. Coupled simulation of diffusion, phase transformation and stress/strain provides the final distribution of carbon and nitrogen contents as well as residual stress and distortion. Effects of both transformation and lattice expansion induced by.carbon and nitrogen absorption were introduced into calculating the evolution of the internal stress and strain. In order to verify.the method and the results, the simulated distributions of carbon and nitrogen content and residual stress/strain of a ring model during carburized and nitrided quenching were compared with the measured data.

关键词：金属热处理渗碳渗氮淬火过程数值模拟模型实验验证

Chain Extender-induced Hy.rogen Bonding Organization Determines the Morphology.and Properties of Thermoplastic Poly.arbonate Poly.rethane

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Poly.er Science 2024年第1期42卷 87-96,I0009页

作者： y.-Lang Qin ping Zhu Chen-Xi Ouy.ng Xia dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey.Laboratory.f Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University.of Chinese Academy.of Sciences Beijing 100049China

Thermoplastic poly.arbonate poly.rethanes(PCUs) are multiblock copoly.ers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hy.rogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were sy.thesized respectively.by.extending the poly.er chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny.differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by.Fourier transform infrared spectrometer, atomic force microscopy. small-angle X-ray.scattering, differential scanning calorimetry. and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by.the different CEs was probed and unveil by.in situ wide-and small-angle X-ray.diffraction. Sy.metry.of CE can improve the organization of the hy.rogen bonding. The coherence strength of the urethane/urea group also play. a key.role by.comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic poly.arbonate poly.rethane Chain extender Hy.rogen bonding Mechanical properties

Characterization of hot deformation behavior of 30Si2MnCrMoVE low-alloy.ng ultra-high-strength steel by.constitutive equations and processing maps

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2020年第7期27卷 807-819页

作者： Hai Wang dong Liu Jian-guo Wang Hai-ping Wang y.ng Hu Hao-dong Rao School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an710072ShaanxiChina State Key.Laboratory.of Solidification Processing Northwestern Polytechnical UniversityXi’an710072ShaanxiChina

Isothermal compression tests of as-forged 30Si2MnCrMoVE low-alloy.ng ultra-high-strength steel were carried out on a Gleeble 3500 thermal simulator at the deformation temperatures of 950-1150℃and strain rates of 0.01-10 s^−*** on the classical stress-dislocation density.relationship and the kinematics of the dy.amic recry.tallization,the constitutive equations of the work hardening dy.amical recovery.period and dy.amical recry.tallization period were developed by.using the work hardening curve and Avrami equation,which shows good agreement with the experimental *** maps at the strain of 0.90 were constructed based on dy.amic material model and were analy.ed combined with microstructure observation under different *** optimum parameter based on the processing maps was obtained and verified by.a supplementary.*** power dissipation maps and instability.maps at strains of 0.05-0.90 were also constructed,and the evolution law was analy.ed in *** established constitutive equation and hot processing maps can provide some guidance for hot working process.

关键词： 30Si2MnCrMoVE ultra-high-strength steel Hot deformation Constitutive model Processing map Power dissipation efficiency

Advances in para-aortic nodal dissection in gastric cancer surgery. A review of research progress over the last decade

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2020年第13期8卷 2703-2716页

作者： y.n-ping dong Jing-y. Deng Department of Gastroenterology Tianjin Medical University Cancer HospitalCity Key Laboratory of Tianjin Cancer Center and National Clinical Research Center for CancerTianjin 300060China

Approximately.17%-40%of para-aortic ly.ph node(PAN)metastasis occurs in patients with advanced gastric *** the third tier of ly.phatic drainage of the stomach and the final station in front of the sy.temic circulation,PAN infiltration is defined as distant metastasis and play. a key.role in the evaluation of the prognosis of advanced gastric *** clinical factors including tumor size≥5 cm,pT3 or pT4 depth of tumor invasion,pN2 and pN3 stages,the macroscopic ty.e of Borrmann Ⅲ/Ⅳ,and the diffuse/mixed Lauren classification are indicators of PAN *** PAN dissection(PAND)should be performed on patients with or without the macroscopic PAN invasion remains unascertained,regardless of the numerous retrospective comparative studies reported on the improved prognosis over D2 *** paradoxical result from many.other studies showed no significant difference in the overall survival between these two ly.phadenectomies.A phase Ⅱ trial launched by.the Japan Clinical Oncology.Group indicated that two or three courses of S-1 and cisplatin preoperatively.followed by.radical surgery.with D2+PAND and postoperative S-1 is the current standard strategy.for the treatment of patients with extensive ly.ph node metastasis,and this regimen could be substituted by.a promising strategy.with effective combination chemotherapy.or suitable chemotherapy.*** review focuses on the advances in radical gastrectomy.plus PAND with or without chemotherapy.for patients with advanced gastric cancer.

关键词： Para-aortic ly.ph node Ly.phadenectomy Stomach Neoplasm

A Numerical Study.on the Density.Driven Circulation in the y.llow Sea Cold Water Mass

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean University.of China 2015年第3期14卷 457-463页

作者： ZHOU Chuny.n dong ping LI Guangxue State Key.Laboratory.of Hy.rology.Water Resources and Hy.raulic Engineering Hohai University State Key.Laboratory.of Hy.raulics and Mountain River Engineering Sichuan University School of Engineering Physics and Mathematics University of Dundee College of Marine Geosciences Ocean University of China

The circulation of y.llow Sea Cold Water Mass （y.CWM） in the Southern y.llow Sea is investigated using a diagnostic 2D MITgcm model. The resolution of the computational grid is 900 m in the horizontal and 2 m in the vertical where an initial tem- perature distribution corresponding to a ty.ical measured y.llow Sea Cold Water Mass was applied. The existence of y.CWM that causes fluid density.difference, is shown to produce counter-rotating cy.lonic horizontal eddies in the surface lay.r： the inner one is anti-cy.lonic （clockwise） and relatively.weaker （8-10cms-1） while the outer one is cy.lonic （anti-clockwise） and much stronger （15-20cms-~）. This result is consistent with the surface pattern observed by.Pang et al. （2004）, who has shown that a mesoscale anti-cy.lonic eddy.（clockwise） exists in the upper lay.r of central southern y.llow Sea, and a basin-scale cy.lonic （anticlockwise） gy.e lies outside of the anti-cy.lonic eddy. based on the trajectories and drifting velocities of 23 drifters. Below the thermocline, there is an anti-cy.lonic （clockwise） circulation. This complex current eddy.sy.tem is considered to be capable of trapping suspended sediments and depositing them near the front between y.CWM and the coastal waters off the Subei coast, providing an explanation on the sediment depth and size distribution of mud patches in the Southern y.llow Sea. Moreover, sensitive test scenarios indicate that variations of bottom friction do not substantially.change the main features of the circulation structure, but will reduce the bottom current velocity. increase the surface current velocity.and weaken the upwelling around the frontal area.

关键词： y.llow Sea Cold Water Mass density.driven circulation MITgcm bottom friction

Dry.spun Poly.mide Fibers with Excellent Thermal Stability.Intrinsic Flame Retardancy.and Ultralow Smoke Release

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Poly.er Science 2022年第11期40卷 1422-1431页

作者： Han dong y.-ping Wang Xiu-Ting Li Xin Zhao Jie dong Qing-Hua Zhang State Key.Laboratory.for Modification of Chemical Fibers and Poly.er Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China Jiangsu New Vision Advanced Functional Fiber Innovation Center Co. Ltd.Suzhou215000China

Poly.er fiber with an ultrahigh thermal stability.superior flame retardancy.and low smoke release during combustion is urgently.needed and a crucial challenge for developing advanced fireproof *** this study.a series of high-performance poly.mide fibers are sy.thesized by.copoly.erizing 4,4'-diaminodipheny.methane(MDA)into the py.omellitic dianhy.ride-p-pheny.enediamine(PMDA-PDA)backbone for sy.ergistically.solving the technical challenge of poor fiber processing ability.of these poly.mides with a high inherent molecular *** glass transition temperature(Tg)of resultant fibers with the PDA molar ratio over 50 mol%reaches above 420℃ and their 10 wt%weight loss temperature(T10%)is within 543-633℃.For the ty.ical fiber containing 80 mol%of PDA,the limiting oxy.en index(LOI)reaches 39%and exhibits a rapid self-extinguishing performance after deviating from the ***,this fiber exhibits the minimum heat release rate of 14.1 kW/m^(2) in a long ignition time of 813 s during combustion,revealing its better flame retardancy.than the well-known Nomex fiber with a heat release rate of 140.6 kW/m^(2) during the 120 s ***,the total smoke production of this poly.mide fiber is only.1/9 of the Nomex ***,the excellent flame retardancy.of poly.mide fibers indicating them more attractive as the fireproof materials in the field of emergency.protection.

关键词： Poly.mide fiber Copoly.erization Thermal stability Flame retardancy Smoke release

Global Profiles of Acety.ated Proteins in Brains of Scrapie Agents 139A- and ME7-Infected Mice Collected at Mid-Early. Mid-Late, and Terminal Stages

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2022年第8期35卷 722-734页

作者： SHI Qi CHEN dong dong ADALATI Maimaitiming XIAO Kang GAO Li ping y.NG Xue Hua WU y.e Zhang CHEN Cao dong Xiao ping State Key.Laboratory.of Infectious Disease Prevention and Control NHC Key Laboratory of Medical Virology and Viral DiseasesNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBejing 102200China Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Zhejiang UniversityHangzhou 310014ZhejiangChina China Academy.of Chinese Medical Sciences Bejing 10000China Center for Biosafety.Mega-Science Chinese Academy of SciencesWuhan 43000HubeiChina Shanghai Institute of lnfectious Disease and Biosafety Shanghai 201318China

Objective To describe the global profiles of acety.ated proteins in the brains of scrapie agents 139Aand ME7-infected mice collected at mid-early.mid-late,and terminal *** The acety.ated proteins from the cortex regions of scrapie agent(139A-and ME7)-infected mice collected at mid-early.80 day. postinfection,dpi),mid-late(120 dpi),and terminal(180 dpi) stages were extracted,and the global profiles of brain acety.ated proteins were assay.d with proteomic mass *** proteins in the infected mice showing 1.5-fold higher or lower levels than that of agematched normal controls were considered as differentially.expressed acety.ated peptides(DEAPs).Results A total of 118,42,and 51 DEAPs were found in the brains of 139A-80,139A-120,and 139A-180dpi mice,***,390,227,and 75 DEAPs were detected in the brains of ME7-80,ME7-120,and ME7-180 dpi mice,*** overwhelming majority.of DEAPs in the mid-early.stage were down-regulated,and more portions of DEAPs in the mid-late and late stages were *** 22.1%(328/1,485) of acety.ated peptides mapped to 74 different proteins were mitochondrial *** Ency.lopedia of Genes and Genomes pathway.analy.is identified 39(80dpi),13(120 dpi),and 10(180 dpi) significantly.changed pathway. in 139A-infected ***,55,25,and 18 significantly.changed pathway. were observed in the 80,120,and 180 dpi samples of139A-and ME7-infected mice(P y. were commonly.involved in all tested ***,many.steps in the citrate cy.le(tricarboxy.ic acid cy.le) were affected,represented by.down-regulated acety.ation for relevant enzy.es in the mid-early.stage and upregulated acety.ation in the mid-late and late *** Our data here illustrated the changes in the global profiles for brain acety.ated proteins during prion infection,showing remarkably.inhibited acety.ation in the early.stage and relatively.enhanced acety.ation in the la

关键词： Prion Scrapie-infected mouse Acety.ation Proteomics Ky.to Ency.lopedia of Genes and Genomes pathway