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Spar Platform Design Considerations for Pre-Service Conditions

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Spar Platform Design Considerations for Pre-Service Conditio...

Case Study-IH 10 Frontage Road Construction Project Development and Management

第十届中国科协年会“深水技术产业发展国际研讨会”

作者： jim j.wang Senior Principal Engineer Technip

As worldwide demand for oil and gas increases and prices reach new high records,the need to develop the vast oil and gas resources from deep and ultra-deep seas becomes *** platform technology has been one of the key enabling technologies for deepwater offshore oil and gas development over the past two *** platform solutions are available that can provide drilling,dry-tree production,work-over, pure wet tree production and/or storage of oil capabilities for water depths up to 3000 meters and beyond. During the past decade,the Spar platform technology has grown quickly and matured from a new concept to 17 Spars installed *** has become one of the most attractive deepwater development concepts due to its superior and robust in-place performance features and dry tree production capability. There have been numerous published papers on Spar platform design and analysis in recent *** of them have generally been focused on Spar in-place performance,such as in hurricane extreme *** papers exist in the literature addressing the unique technical issues and design challenges for Spar pre-service *** temporary conditions include Spar hull load-out,dry transportation,float-off,wet tow,upending and topside *** pre-service conditions can govern certain aspects of the Spar platform design from structural global configuration to local structural details and from transportation sea fastening,offshore installation aids to marine ballast ***,the pre-service conditions generally have a significant impact on a project’ s success in terms of safety,schedule and *** paper provides an overview of the pre-service stages and processes during the design and execution of a Spar *** technical and non-technical factors and design considerations for the pre-service conditions will be discussed.

关键词： Spar design deepwater floating systems Spar transportation topside floatover

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Case Study-IH 10 Frontage Road Construction Project Developm...

Effects of effective stress and temperature on permeability of sandstone from CO2-plume geothermal reservoir

第六届交通运输领域国际学术会议

作者： Alan j.wang Texas Department of Transportation USA

＜正＞This paper presents a real case study to demonstrate how a highway construction project were developed and managed;and what kinds of coordination were conducted to ensure the project to be developed effectively and within a timely manner. The purposes of this paper are to address the importance of project design procedures and key management aspects that are associated with the transportation systems development.

关键词： Highway Design Transportation Project Development & Management Roadway Construction Utility Coordination Traffic Control Environmental Cleaning Hydraulic Flood Mitigation Structure Design Exemption

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journal of Rock Mechanics and Geotechnical Engineering 2016年第6期8卷 819-827页

作者： Y.Z.Sun L.Z.Xie B.He C.Gao j.wang College of Architecture and Environment Sichuan UniversityChengdu610065China MOE Key Laboratory of Energy Engineering Safety and Disaster Mechanics Sichuan UniversityChengdu610065China Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu610065China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu610065China

Rock is generally complex and heterogeneous,therefore the heterogeneity effects of effective stress and temperature on permeability should be taken into *** this study,two-part Hooke’s model（TPHM） is introduced to understand the influences of effective stress and temperature on permeability of soft and hard parts（two parts） of rock based on coupling thermo-hydro-mechanical *** a fixed temperature level（25 ℃.35 ℃.50 ℃.65 ℃.80 ℃.90 ℃ and 95 ℃）.the tests were carried out in a conventional triaxial system whereas the confining pressure was remained at 50 *** the pore pressure was increased to the specified levels step by step.i.e.8 MPa,18 MPa.28 MPa.38 MPa.41 MPa,44 MPa.46 MPa and 48 *** temperature-dependent relationships for two parts permeabilities are proposed on the basis of the initial test *** point out that temperature of 65 ℃-90 ℃ is the threshold for the development of CO2-plume geothermal（CPC） reservoir sandstone cracking under low effective stress（2-9 MPa） based on the relationship between temperature and soft part ***,we discuss the effect of temperature on the two parts in the *** results indicate that as the temperature increases from 25 ℃ to 65 ℃.the flow channel in the hard part has a stronger response to temperature than that in the soft part at a fixed effective stress level,which is opposite to the situation of effective *** that natural rock is generally heterogeneous with non-uniform pore structure,we suggest a physical interpretation of the phenomenon that before the thermal cracking threshold the two parts have different responses to temperature.

关键词： Sandstone from CO2-plume geothermal (CPG) reservoir Temperature and effective stress Flow channel Two parts permeabilities

An insight into a novel Mg2InSm prismatic plate in Mg-In-Sm alloy

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journal of Materials Science & Technology 2022年第30期125卷 222-230页

作者： j.wang X.L.Lu Y.Tian Q.Y.Huang H.B.Xie B.Z.Sun L.R.Liu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Prismatic precipitate platelet is always purposefully designed in the microstructure of magnesium alloys due to its greater contribution to yield *** this study,with an introduction of In into Mg-Sm system,a category of novel{1010}_(α) prismatic platelets has replaced thoroughly the traditionalβ’precipitate formed in magnesium rare earth(Mg-RE)***,the microstructural characteristics of platelet are investigated particularly by atomic scale scanning transmission electron *** is confirmed that the platelet has a Mg_(2) InSm composition and can maintain a coherent relationship with α-Mg ***,on account of the similarities between In and Mg atoms,the Mg_(2) InSm prismatic platelet could be structurally categorized as a generalizedβ"precipitate with a(Mg_(2) In)Sm-type DO_(19) structure when both In and Mg are regarded as an equivalent ***,the addition of In into Mg-Sm alloy induces the formation ofβ"***,the formedβ"prismatic platelets generally have a large average aspect *** findings are of great significance to construct the effective precipitation strengthening phases and optimize the microstructure of Mg-based alloys.

关键词： Microstructure Scanning transmission electron microscopy Magnesium alloys Prismatic platelet Generalizedβ"precipitate

Synthesis of Ni nanowires via a hydrazine reduction route in aqueous ethanol solutions assisted by external magnetic fields

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Nano-Micro Letters 2009年第1期1卷 49-52页

作者： L.Y.Zhang j.wang L.M.Wei P.Liu H.Wei Y.F.Zhang National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiao Tong University

One-dimensional Ni nanostructures were synthesized via a hydrazine reduction route under external magnetic fields. The mixture of de-ionized water and ethanol was used as the reaction solvent and hydrazine hydrate as reducing agents. The morphology and properties of Ni nanostructures were characterized by X-ray diffractometer(XRD), scanning electron microscopy(SEM), and vibrating sample magnetometer(VSM). It was found that the magnetic field strength, concentration of Ni ions,reaction time and temperature as well as p H values played key roles on formation, microstructures and magnetic properties of Ni nanowires. The optimal wires have diameter of ~200 nm and length up to ~200 μm. And their coercivity is ~260 Oe, which is much larger than the commercial Ni powders of 31 Oe. This work presents a simple, low-cost, environment-friendly and large-scale production approach to fabricate one-dimensional magnetic materials. The resulting materials may have potential applications in conductive filters, magnetic sensors and catalytic agents.

关键词： Ni fiber Hydrazine reduction Magnetic field Magnetic properties

B3 0749+460A: A New Repeat “Changing-look” Active Galactic Nucleus Associated with X-Ray Spectral Slope Variations

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Research in Astronomy and Astrophysics 2022年第1期22卷 114-125页

作者： j.wang W.K.Zheng D.W.Xu T.G.Brink A.V.Filippenko C.Gao S.S.Sun j.Y.Wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Astronomy University of CaliforniaBerkeleyCA 94720-3411USA School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Miller Institute for Basic Research in Science University of CaliforniaBerkeleyCA 94720USA

Here we report an identification of B3 0749+460 A as a new double-peaked local "changing-look" active galactic nucleus(CL-AGN) in terms of our multi-epoch spectroscopic analysis. By comparing our new spectra taken in 2021 with the ones taken by the Sloan Digital Sky Survey in 2004, BOSS in 2013 and Ma NGA in 2016, we reveal type transitions of Seyfert(Sy) 1.9 → Sy1.8 → Sy1.9. In the transitions, the classical broad Hα emission fades away after 2013 and disappears in our 2021 spectrum, although the absence of broad Hβ can be traced back to at least 2016. A follow-up observation in X-rays by the Swift/XRT reveals that(1) the X-ray emission level gradually decreased since 2005;and(2)the X-ray spectrum is soft in the optical "turn-off" state and hard in the "turn-on" state. We argue that the disappearance of the classical broad Hα emission can be likely explained by the disk-wind broad-line-region model, in which the CL phenomenon is sensitive to luminosity in individual AGNs.

关键词： galaxies:Seyfert galaxies:nuclei (galaxies:)quasars:emission lines (galaxies:)quasars:individual(B30749+460A) X-rays:galaxies

Microstructural characteristics and mechanical properties of the hot extruded Mg-Zn-Y-Nd alloys

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journal of Materials Science & Technology 2021年第1期60卷 44-55页

作者： B.N.Du Z.Y.Hu L.Y.Sheng D.K.Xu Y.X.Qiao B.j.wang j.wang Y.F.Zheng T.F.Xi Shenzhen Institute Peking UniversityShenzhen 518057China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China jiangsu University of Science and Technology Zhenjiang 212003China Shenzhen Yezhan Electronics Co. LtdShenzhen 518110China

A new type of Mg-Zn-Y-Nd alloy for degradable orthopedic implants was *** the present study,the Zn and Y content was adjusted and their influences on the microstructures and mechanical behaviors were discussed in *** results showed that the as-extruded Mg-Zn-Y-Nd alloys are mainly composed of fine dynamic recrystallized grains(DRXed grains),la rge unDRXed grains and linearly distributed secondary *** cha nge of Zn content exerts little influence on the grain structure of the extruded Mg-Zn-Y-Nd alloy,while the increase of Y content would hinder the dynamic recrystallization process and the growth of the DRXed grains,thus the size and volume fraction of the equiaxed DRXed grains *** tensile and compressive properties are very little affected by Zn content because of the similar grain *** Y content increases,the tensile yield strength(TYS) and ultimate strength(TUS) increase while the elongation decreases,this is caused by a combined strengthening effect of grain refinement,texture,precipitation and *** compressive yield strength(CYS) and ultimate strength(CUS) of Mg-Zn-Y-Nd alloy with diffe rent Y content exhibit a similar tendency as the tensile test.

关键词： Mg-Zn-Y-Nd alloy Microstructure Tensile properties Compressive properties Basal texture Twin

快速热处理对应变InGaAs/GaAs单量子阱激光二极管电子发射和DX中心的影响

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物理学报 2002年第2期51卷 367-371页

作者：卢励吾张砚华徐遵图徐仲英王占国 j.wang WeikunGe 中国科学院半导体研究所半导体材料科学开放实验室北京100083 中国科学院半导体研究所光电子工程中心北京100083 中国科学院半导体研究所半导体超晶格国家重点实验室北京100083 香港科技大学物理系

研究分子束外延 (MBE)生长的应变In0 .2 Ga0 .8As GaAs折射率梯度变化异质结单量子阱激光二极管的快速热处理 (RTA)效应 .结果表明 ,RTA移除了InGaAs GaAs界面非辐射中心 ,提高 77K光致发光效率和有源层电子发射 .同时Al和Ga原子互扩散 ... 详细信息

研究分子束外延 (MBE)生长的应变In0 .2 Ga0 .8As GaAs折射率梯度变化异质结单量子阱激光二极管的快速热处理 (RTA)效应 .结果表明 ,RTA移除了InGaAs GaAs界面非辐射中心 ,提高 77K光致发光效率和有源层电子发射 .同时Al和Ga原子互扩散 ,也增加了AlGaAs波导层DX中心浓度 .RTA处理后样品电流冲击老化实验证明DX中心浓度呈现出相应的增加 .这表明DX中心可能是激光二极管性能退化的原因之一 .

关键词：量子阱快速热处理电子发射 DX中心激光二极管 RTA InGaAs/GaAs 半导体激光器铟镓砷化合物砷化镓

Numerical analysis of thermal process in the near field around vertical disposal of high-level radioactive waste

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journal of Rock Mechanics and Geotechnical Engineering 2014年第1期6卷 55-60页

作者： H.G.Zhao H.Shao H.Kunz j.wang R.Su Y.M.Liu CNNC Key Laboratory on Geological Disposal of High-level Radioactive Waste Beijing Research Institute of Uranium Geology(BRIUG) Federal Institute for Geosciences and Natural Resources(BGR)

For deep geological disposal of high-level radioactive waste(HLW)in granite,the temperature on the HLW canisters is commonly designed to be lower *** criterion dictates the dimension of the *** on the concept of HLW disposal in vertical boreholes,thermal process in the nearfield(host rock and buffer)surrounding HLW canisters has been simulated by using different *** results are drawn as follows:(a)the initial heat power of HLW canisters is the most important and sensitive parameter for evolution of temperaturefield;(b)the thermal properties and variations of the host rock,the engineered buffer,and possible gaps between canister and buffer and host rock are the additional key factors governing the heat transformation;(c)the gaps width and thefilling by water or air determine the temperature offsets between them.

关键词： High-level radioactive waste(HLW) Vertical disposal Engineered barrier system(EBS) Thermal conductivity properties