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青藏高原及其周边志留纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1026-1057页

作者：陈中阳陈清王光旭方翔唐鹏闫冠州袁文伟黄冰张小乐燕夔张元动王怿中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学北京100049

青藏高原志留纪的古生物学与地层学研究已有百余年的历史,随着第二次青藏高原综合科学考察研究项目的启动,对于青藏高原志留纪的地层系统和化石群的总结,及其与周边地区的对比亟待更新.本文在青藏高原及其周边选择了33条代表剖面,从地... 详细信息

青藏高原志留纪的古生物学与地层学研究已有百余年的历史,随着第二次青藏高原综合科学考察研究项目的启动,对于青藏高原志留纪的地层系统和化石群的总结,及其与周边地区的对比亟待更新.本文在青藏高原及其周边选择了33条代表剖面,从地层区划、岩石地层、年代地层和生物地层等方面,对已有的资料进行了总结,将青藏高原及其周边划为了4个地层区:西藏-滇西-川西地层区、昆仑-祁连地层区、华南地层区和塔里木地层区.其中青藏高原主体部分被划入了西藏-滇西-川西地层区,该地层区地层和生物组合发育基本完整,一定程度上弥补了我国其他地区志留系研究的不足.通过对志留纪青藏高原及其周边古生物地理研究的总结,尤其是对鱼类动物群、孢型植物组合和腕足动物群分布特征的梳理,指出华南、塔里木和印支等三大板块之间的关系应该比此前认为的更为密切.与研究程度较高的周边地区相比,青藏高原主体部分的志留系尚处于初步研究阶段,诸多问题和领域有待开展和深入研究.未来需要对志留系底部黑色岩系的时限、分布和资源量进行研究,为我国未来页岩气勘探开发提供新的方向.志留系中-上部浅海地层需要进行进一步的划分.由于青藏高原地区的志留系发育较完整,在生物地层学工作基础上,更有潜力补充和完善我国志留纪的碳同位素地层学研究.

关键词：青藏高原志留纪地层区划岩石地层生物地层古地理演化

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酰胺质子转移加权成像及其衍生的影像组学在成人弥漫性胶质瘤分类中的应用

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国际医学放射学杂志 2024年第4期 496-496页

作者： M.H.Wu T.L.Jiang M.Guo y.y.Duan z.z.zhuo J.y.Weng 程昊

摘要目的评估酰胺质子转移加权（ApTw）MRi及其衍生的影像组学在成人弥漫性胶质瘤分类中的应用价值。方法前瞻性纳入129例行ApTw成像的成人弥漫性胶质瘤病

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钆苯二胺增强MRi定量信息可以预测孤立性肝细胞癌增殖亚型：一项多中心回顾性研究

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国际医学放射学杂志 2024年第3期 379-379页

作者： F.Ding M.Huang p.Ren J.zhang z.Lin y.Sun 孔令红

摘要目的研究钆苯二胺增强MRi定量参数在预测肝细胞癌（HCC）分子亚型及总生存期方面的价值。方法该项多中心回顾性研究纳入218例完成钆苯二胺增强MRi检查

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Fatigue properties improvement of Low-Carbon Alloy Axle Steel by induction Hardening and Shot peening:A prospective Comparison

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Acta Metallurgica Sinica(English Letters) 2022年第8期35卷 1343-1356页

作者： G.C.Chu F.z.Hu X.J.jin y.zhang Q.Wang J.p.Hou z.F.zhang Shi-Changxu innovation Center for Advanced Material Institute of Metal ResearchChinese Academy of SciencesShenyang 110016.China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Manshan iron and Steel Co. Ltd.Maanshan 243000China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Baowu Group Masteel Rail Transit Materials Technology Company Limited Maanshan 243000China

Fatigue fracture is the major threat to the railway axle, which can be avoided or delayed by surface strengthening. in this study, a low-carbon alloy axle steel with two states was treated by surface induction hardening and shot peening, respectively, to reveal the mechanism of fatigue property improvement by microstructure characterization, microhardness measurement, residual stress analysis, roughness measurement, and rotary bending fatigue tests. The results indicate that both quenching and tempering treatment can effectively improve the fatigue properties of the modified axle steel. in addition, induction hardening can create an ideal hardened layer on the sample surface by phase transformation from the microstructure of ferrite and pearlite to martensite. By comparison, shot peening can modify the microstructure in surface layer by surface severe plastic deformation introducing a large number of dislocation and even cause grain refinement. Both induction hardening and shot peening create compressive residual stress into the surface layer of axle steel sample, which can effectively reduce the stress level applied to the metal surface during the rotary bending fatigue tests. On the whole, the contribution of induction hardening to the fatigue life of axle steel sample is better than that of the shot peening, and induction hardening shows obvious advantages in improving the fatigue life of axle steel.

关键词： Surface strengthening induction hardening Shot peening Axle steel Fatigue property improvement

Non‐chromate conversion process for zinc coating with durable hydrophobicity and enhanced corrosion resistance

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Biosurface and Biotribology 2022年第3期8卷 266-277页

作者： J.y.Chen z.y.Hu z.X.Li X.L.Wang C.D.Gu J.p.Tu School of Materials Science and Engineering State Key Laboratory of Silicon MaterialsZhejiang UniversityHangzhouChina Key Laboratory of Advanced Materials and Applications for Batteries of zhejiang province HangzhouChina zhejiang Ecological and Environmental Monitoring Center HangzhouChina zhejiang Key Laboratory of Ecological and Environmental Monitoring Forewarning and Quality ControlHangzhouChina

A zn‐based coating with durable hydrophobicity and good corrosion resistance was formed on a mild steel substrate,which involves electroplating zn from a non‐aqueous electrolyte,followed by passivation in an oleic acid(OA)*** electrodeposited zn coatings were porous,which facilitated the formation of a chemical conversion layer of zn oleate(zO)during OA *** zn coating after passivation had a twolayer structure,which included an outer layer of zO with a thickness of~26μm and an inner layer of zn with a thickness of~6μ*** outer layer zO is a type of metal soap with a smooth surface and durable hydrophobicity,such that water droplets can easily slip off its *** testing and electrochemical measurements in 3.5 wt.%NaCl aqueous solution indicate that the zn coating after OA passivation exhibits outstanding anti‐corrosion properties compared with those exhibited by pure zn *** corrosion products and mechanism of the two‐layer coating were *** study shows that smooth metal oleate coatings can provide hydrophobicity and corrosion resistance simultaneously to mild steel substrates.

关键词： Anti‐corrosion Electrodeposition Hydrophobic coating passivation zn oleate

青藏高原及其周边第四纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1379-1410页

作者：王永郑绵平凌媛向树元邵兆刚张克信柯学林晓韩芳韩建恩中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所北京100037 中国地质大学(武汉)地球科学学院武汉430074 中国地质科学院北京100037 中国地质大学(武汉)地质调查研究院武汉430074 东华理工大学地球科学学院南昌330013 中国地质科学院地质力学研究所北京100081

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉... 详细信息

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉积特征及地貌、流域水系的差异,将青藏高原及其周边第四纪地层划分为5个地层区:塔里木区、黄土高原区、青藏高原区、云贵高原区及印度-恒河区.并将青藏高原地层区划分为西昆仑-喀喇昆仑分区、阿尔金-祁连山分区、柴达木-河湟分区、东昆仑-巴颜喀拉分区、羌塘分区、藏东-滇西-川西分区及冈底斯-喜马拉雅分区等7个地层分区.简要描述了青藏高原7个地层分区的岩石地层单元,根据各个地层分区的岩石地层序列及其沉积特征、地层接触关系、形成时代与生物群演化,将青藏高原第四纪的构造古地理演化划分为4个阶段:(1) 2.6~1.8/1.5Ma,上新世以来继承性差异隆升阶段,区域沉积差异显著,地层分布较局限,沿山前地带普遍发育冲洪积砂砾岩,山间低洼地河湖相沉积发育;(2) 1.8/1.5~1.2/0.8Ma,高原整体夷平阶段,高原及周边不整合面广泛分布,大型河流形成,山间盆地及高原腹地发育湖泊沉积物;(3) 1.2/0.8~0.128Ma,高原大范围持续隆升,地形差异显著,山体切割加剧,约0.8Ma高原进入冰冻圈,山地冰川发育,高寒干旱环境逐步形成;(4)0.128Ma~,山体上升与侵蚀切割加剧,山间盆地湖泊广泛分布,区域沉积特征差异较大,沉积类型向多样化发展,现代高原地貌格局基本形成.

关键词：青藏高原第四纪地层对比生物群古地理

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Accelerated protons with energies up to 70 MeV based on the optimized SG-Ⅱ peta-watt laser facility

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High power Laser Science and Engineering 2023年第5期11卷 127-136页

作者： H.H.An W.Wang J.Xiong C.Wang X.pan X.p.Ouyang S.Jiang z.y.Xie p.p.Wang y.L.yao N.Hua y.Wang z.C.Jiang Q.Xiao F.C.Ding y.T.Wan X.Liu R.R.Wang z.H.Fang p.Q.yang y.E.Jiang p.z.zhang B.Q.zhu J.R.Sun B.Qiao A.L.Lei J.Q.zhu Shanghai institute of Laser plasma China Academy of Engineering PhysicsShanghaiChina Shanghai institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghaiChina Center for Applied physics and Technology Peking UniversityBeijingChina National Laboratory on High power Laser and physics ShanghaiChina

The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration(LDpA)and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving *** successful use of the SG-ii peta-watt(SG-ii pW)laser facility for LDpA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-ii pW ***,the SG-ii pW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source,laser contrast and terminal *** experiments were performed using the maintained SG-ii pW laser beam,and the highest cutoff energy of the proton beam was obviously ***,a double-film target structure was used,and the maximum cutoff energy of the proton beam was up to 70 *** results demonstrate that the comprehensive performance of the SG-ii pW laser facility was improved significantly.

关键词： laser-driven proton acceleration SG-ii peta-watt laser target normal sheath acceleration

基于状态空间模型的激光再制造熔池温度控制系统

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表面工程与再制造 2024年第2期24卷 50-50页

作者： yang G.-z. Liu T.-M. Song B.-X. Jiang X.-y. Wang z.-S. Chen K.-Q. Liu W.-J. School of Mechanical Engineering Shenyang University of Technology Shenyang China

激光再制造是用于再制造的一项重要技术,在航空航天、冶金、能源等领域应用广泛。然而,形状控制问题一直是制约其规模化和工业化应用的瓶颈。在激光再制造过程中,熔池温度是决定再制造件形状和性能稳定性的关键。基于此,本文提出了一种... 详细信息

激光再制造是用于再制造的一项重要技术,在航空航天、冶金、能源等领域应用广泛。然而,形状控制问题一直是制约其规模化和工业化应用的瓶颈。在激光再制造过程中,熔池温度是决定再制造件形状和性能稳定性的关键。基于此,本文提出了一种基于状态空间模型的激光再制造熔池温度实时在线控制方法,解决了控制机理模型难以建立和多变量约束的问题。

关键词：状态空间模型激光再制造熔池温度航空航天形状控制控制系统变量约束性能稳定性

Dislocation ordering and texture strengthening of naturally aged Al-Cu-Mg alloy

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Journal of Materials Science & Technology 2022年第23期118卷 1-14页

作者： F.Liu z.y.Liu G.y.He L.N.Ou School of Materials Science and Engineering Central South UniversityChangsha 410083China Key Laboratory of Nonferrous Metal Materials Science and Engineering Ministry of EducationCentral South UniversityChangsha 410083China National Key Laboratory of Science and Technology on High-Strength Structural Materials Central South UniversityChangsha 410083China

Stability of grain structure,dislocation ordering and strengthening mechanisms of the naturally aged AlCu-Mg alloy after solution treatment are investigated by using optical microscope(OM),scanning electron microscope(SEM),electron back-scattered diffraction(EBSD),X-ray diffraction(XRD) and transmission electron microscope(TEM).Results show that {100},{100},{110} and {110}slip systems can be activated after solution treatment,which can promote the formation of {110}Goss *** combination effect of T-Al_(20)Cu_(2) Mn_(3) phase and Goss-oriented grains with large Taylor factor makes the solution-treated alloys display excellent stability of grain *** enhanced yield strength of the alloy is ascribed to grain-refine strengthening,dispersed particles strengthening,dislocation strengthening and texture *** coarsening of the second phase is responsible for softening of the alloy after annealing at 400 ℃+solution treatment at 475 ℃.

关键词： Al-Cu-Mg alloy Dislocation ordering Goss texture Grain structure stability Texture strengthening