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China Ocean Engineering 2022年第3期36卷 384-394页

作者： SHEN Yu-sheng PAN Jun-ning ZHOU yi-ren WANG Xing-gang River and Harbour Engineering Department Nanjing Hydraulic Research InstituteNanjing 210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210024China

A floating breakwater(FB)has extensive potential applications in the fields of coastal,offshore,and ocean engineering owing to its advantages such as eco-friendliness,low cost,easy and rapid construction,and quick dismantling and *** FB composed of twin pontoons and multi-porous vertical plates is proposed to improve the wave attenuation *** wave attenuation performance is investigated for different FB structures and vertical plate types under different incident wave heights and periods using 2D wave physical model tests in a wave *** results demonstrate that the proposed FB has a better performance than that of the conventional single pontoon-type *** reduces the wave transmission due to its enhanced wave reflection and energy *** wave transmission coefficient of the proposed FB decreases with an increase in the number of layers and relative draft depth of the vertical ***,a further decrease in the wave transmission coefficient is not observed when the number of porous vertical plates is increased from 4 to 5 *** equation has been derived to predict the wave transmission of the proposed FB based on the experimental results.

关键词： Floating breakwater twin pontoons porous vertical plates layer numbers relative draft wave attenuation performance experimental model test

Relationship between microstructure and corrosion behavior of high-grade pipeline steel in a low-temperature environment

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Journal of Iron and Steel Research International 2021年第8期28卷 1037-1046页

作者： Jia-qiang Jing Jie Guo Ba Li Shu-jun Jia yi ren School of Oil and Gas Engineering Southwest Petroleum UniversityChengdu 610500SichuanChina Department of Structural Steels Central Iron and Steel Research InstituteBeijing 100081China State Key Laboratory of Metal Material for Marine Equipment and Application of Iron and Steel Research Institutes of Ansteel Group Corporation Anshan 114009LiaoningChina

The relationship between micro structure and corrosion behavior of high-grade pipeline steel under low-temperature conditions was comparatively investigated by the potentiodynamic polarization and electrochemical impedance spec-troscopy test combining with optical micrographs,scanning electron microscopy,transmission electron microscopy and electron back-scattered *** results showed that,compared with room and high temperature,low temperature could influence the corrosion behavior of high-grade pipeline steel,which means that the corrosion potential and current density decreased and the corrosion resistance increased ***,double layer structures of the interface became thicker and more *** low-temperature environment,acicular ferrite had the martensite/austenite constituents with less amount and smaller size,a higher density of low angle grain boundaries and smaller effective grain sizes compared with granular bainite,which demonstrated higher corrosion resistance.

关键词： Low temperature High-grade pipeline steel Corrosion behavior Resistance Acicular ferrite Granular bainite Martensite/austenite constituent

The Dynamical Effects of a Large-Scale Ordered Magnetic Field on Slim Disks

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Chinese Physics Letters 2013年第5期30卷 195-197页

作者： PING Chong MA ren-yi LU Ju-Fu Department of Astronomy and Institute of Theoretical Physics and Astrophysics Xiamen UniversityXiamen 361005

The dynamics of slim disk under the influence of a large-scale ordered magnetic field is *** global solutions show that the radial velocity increases and the disk temperature decreases with enhancing magnetic *** fraction of mass loss becomes smaller when the accretion rate is *** ratio of the jet kinetic power to disk luminosity is less than 0.1,which indirectly supports the argument that radio-loud narrow-line Seyfert 1 galaxies share similarities with blazars.

关键词： galaxies field narrow

A huge pancreatic lipoma mimicking a well-differentiated liposarcoma: A case report and systematic literature review

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World Journal of Clinical Cases 2019年第16期7卷 2352-2359页

作者： ren-yi Xiao Xing Yao Wei-Lin Wang Division of Hepatobiliary and Pancreatic Surgery Department of General SurgeryThe Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009Zhejiang ProvinceChina Department of General Surgery Huzhou Central HospitalHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Pancreatic lipomas are thought to be very *** are usually easy to identify on imaging,particularly via computed tomography (CT).But sometimes it’s quite difficult to distinguish a lipoma from a well-liposarcoma without histologic *** SUMMARY Here,we present a case of pancreatic lipoma in a 59-year-old *** was asymptomatic and had no medical history of *** and magnetic resonance imaging revealed a mass like well-differentiated liposarcoma in the pancreatic head,positron emission tomography/CT showed a low fluorodeoxyglucose uptake and laboratory tests revealed elevated transaminase and carbohydrate antigen-199 ***,the patient underwent a ***,mature adipocytes were noted in the bulk of the ***,the pathologic diagnosis of the pancreatic neoplasm was *** our knowledge,this case is the first example of a suspected well-differentiated liposarcoma that was actually a pancreatic *** also highlight the radiological features distinguishing a pancreatic lipoma from a pancreatic liposarcoma and briefly review the *** Pancreatic lipomas show no obvious gender bias and most commonly occur in the head of the pancreas,of which the maximum diameters are often less than 5 cm,and small,asymptomatic non-compressed lipomas require follow-up *** excision should be considered when the tumor has compressed important tissues or is difficult to distinguish from a liposarcoma,the choice of surgery depends on the intraoperative presentation.

关键词： Pancreatic Lipoma Liposarcoma Pancreas Case report

Two new diterpenoids from Suregada glomerulata(Blume) Baill

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Chinese Chemical Letters 2011年第5期22卷 580-582页

作者： ren yi Yan Ruo Yun Chen De Quan Yu Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing 100700 China

Two new diterpenoids,3,4,18β-cyclopropa-ent-abieta-8（14）,13（15）-dien-16,12-olide（1） and 3-oxojolkinolide B（2）,were isolated from the roots of Suregada glomerulata（Blume） *** structures were determined by sp... 详细信息

关键词： Suregada glomerulata Diterpenoid 3 4 18β-Cyclopropa-ent-abieta-8(14) 13(15)-dien-16 12-olide 3-Oxojolkinolide B Cytotoxicity

Strength, strain capacity and toughness of five dual-phase pipeline steels

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Journal of Iron and Steel Research International 2021年第6期28卷 752-761页

作者： yi ren Xian-bo Shi Zhen-guo Yang yi-yin Shan Wei Ye Gui-xi Cai Ke Yang State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114009LiaoningChina CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina

The effect of microstructures on strength,strain capacity and low temperature toughness of a micro-alloyed pipeline steel was *** various dual-phase microstructures,namely,acicular ferrite and a small amount of(around 2 vol.%)polygonal ferrite(AF+PF),polygonal ferrite and bainite(PF+B),polygonal ferrite and martensite/austenite islands(PF+M/A),polygonal ferrite and martensite(PF+M)and elongated polygonal ferrite and martensite(ePF+M),have been *** results show that AF+PF microstructure has high yield strength and excellent low temperature toughness,whereas its yield ratio is the *** ferrite-based dual-phase steels,PF+B,PF+M/A and PF+M microstructures show better strain capacity and low temperature *** strain capacity and low temperature toughness of ePF+M microstructure are the worst due to its high *** relationship between microstructure,strength,strain capacity and toughness has been *** on the results,the optimum microstructure for a better combination of strength,strain capacity and toughness is suggested to be the one having appropriate polygonal ferrite as second phase in an acicular ferrite matrix.

关键词： Pipeline steel Dual-phase microstructure Strength Strain capacity Toughness

Distribution and segregation of dissolved elements in pipeline slab

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Journal of University of Science and Technology Beijing 2007年第3期14卷 212-218页

作者： Jianhua Liu Yanping Bao Xian Dong Taiquan Li yi ren Shuai Zhang Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijng 100083 China Technology Center of ANSC Angang Steel Company Limited Anshan 114001 China

The chemical composition in a cross section of a high grade pipeline slab was measured point by point （in a scale of 1 μm） using original position statistic distribution analysis （OPA）. The result indicated that negative segregation strips of Si, Mn, Mo, Ni, Cr, Nb, Cu, Ti, and V exist in the two sides 24 mm away from the central line, with a width of 8-12 mm, Negative segregation inside the central line is more severe than that outside the central line, and the highest positive segregation of the elements appears closely by the inner sides of the negative segregation strips. No obvious negative segregation strip of S and P is found. Segregation of the elements in the central area is higher than that in the outer and inner arc areas. The segregation of C, Ti, S, and P is high and that of Cr, Cu, Si, and Mn is low in the slab.

关键词： original position statistic distribution analysis (OPA) segregation negative segregation pipeline

Effect of Pre-deformation on Grain Ultrafining by Intercritical Deformation in Low-Carbon Microalloyed Steels

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Acta Metallurgica Sinica(English Letters) 2018年第10期31卷 1038-1048页

作者： Ba Li Qing-You Liu Shu-Jun Jia yi ren Bing Wang Central Iron and Steel Research Institute Beijing 100081China Iron and Steel Research Institute Ansteel Group Co. Ltd.Anshan 114009 China

In this study, the effect of pre-deformation at recrystallization and non-recrystallization zone on the grain ultrafining by the subsequent intercritical deformation （ID） was investigated on low-carbon microalloyed steel. The results showed that ultrafine grain microstructure with an average size of - 1.0 μm was fabricated through pre-deformation in the recrys- tallization zone followed by ID. When pre-deformed at the non-recrystallization zone prior to ID, the grain size increased to 1.6 μm with a heterogeneous distribution along with the well-developed dynamic recovery of ferrite. The grain ultrafining mechanism was attributed to the combined action of the deformation-induced ferrite transformation and the continuous dynamic recrystallization. In particular, the continuous dynamic recrystallization process during ID occurred on the pro-eutectoid ferrite as a result of the subgrain rotation mechanism and the absorbing dislocations mechanism.

关键词： Low-carbon microalloyed steels Intercritical deformation Ultrafine grain Continuous dynamic recrystallization Deformation-induced ferrite transformation

DRILLING CHARACTERISTICS OF COMBINATIONS OF DIFFErenT HIGH PRESSURE JET NOZZLES

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Journal of Hydrodynamics 2011年第3期23卷 384-390页

作者： ZHANG Yu-ying LIU Yong-wang XU yi-ji ren Jian-hua College of Petroleum Engineering China University of Petroleum （East China） Dongying 257061 China

The high speed fluid jet for directly or indirectly breaking rock is one of the most effective ways to improve the deep penetration rate. In order to maximize the efficiency of energy use, the flow characteristics of different combinations of high pressure jet nozzles are analyzed through numerical simulations. According to the velocity vectors at the bottom and the bottom hole pressure diagram, the effects of the high pressure nozzle combinations on the flow structure and the penetration rate are analyzed. It is shown that the combination of three vertical edge nozzles is very efficient, but inefficient in cleaning the bottom hole and eroding the wall. The jet velocity is 400 m/s and the radius is 5 mm, with a center nozzle added, the problem can be solved, but the high-pressure fluid displacement would increase. The center nozzle＇s jet velocity is 200 m/s and the radius is 8 ram, the combination of two vertical edge nozzles and a center tilt nozzle or that of a vertical edge nozzle and a center tilt nozzle would provide a flow structure favorable for drilling. The angle of inclination is 10°. To take advantage of high pressure jet energy to improve the efficiency of drilling, it is important to select a suitable nozzle combination according real conditions.

关键词： Rate Of Penetration (ROP) rock breaking high pressure jet nozzle combination numerical simulation energy use

The Effect of Polymer-Substrate Interaction on the Nucleation Property:Comparing Study of Graphene and Hexagonal Boron Nitride Nanosheets

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Chinese Journal of Polymer Science 2016年第8期34卷 1021-1031页

作者： yi-ren Tang Ting Li Hai-mu Ye 徐军郭宝华 Advanced Materials Laboratory of Ministry of Education Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Department of Materials Science and Engineering China University of PetroleumBeijing 102249China

Hexagonal boron nitride nanosheets （BNNSs） can work as a more efficient nucleating agent for two polyesters compared to graphene. Studies on the crystallization and dewetting processes of two polyesters, poly（butylene succinate） and poly（butylene adipate）, on the two substrate surfaces prove that the interaction between BNNSs and the polyesters is stronger than that between graphene and the polyesters. This strong interaction induces the pre-ordered conformation of molten PBA which has been identified by the in situ FTIR spectra. Thus BNNSs possess higher nucleation property than graphene. Finally, a new polymer-substrate interaction induced nucleation mechanism was proposed to explain the nucleation efficiency difference between graphene and BNNSs.

关键词： Hexagonal boron nitride nanosheets Graphene Crystallization Dewetting Interaction.