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Mechanisms and climatic-ecological effects of the Great Oxidation Event in the early Proterozoic

Science China Earth Sciences 2022年第9期65卷 1646-1672页

作者： Genming LUO Xiangkun ZHU Shuijiong WANG shihong zhang Chaoqun JIAO State Key Laboratory of Biogeology and Environmental Geology and School of Earth SciencesChina University of GeosciencesWuhan 430074China MNR Key Laboratory of Isotope Geology MNR Key Laboratory of Deep-Earth DynamicsInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China

This paper briefly introduces the conception and research history of the Great Oxidation Event(GOE) in the early Paleoproterozoic and summarizes the primary geological and geochemical records of this event. On the basis of these, we overview the significant progress in three fields of the GOE: the timing and process of its startup, its mechanisms, and its climatic-ecological effects. The records of mass-independent fractionation of sulfur isotopes suggest that the startup of the GOE might be multi-episodic, which is obviously inconsistent with the single-episodic opinion obtained from atmospheric model simulations. The fundamental mechanism of the GOE was the source of the atmospheric Oexceeding the sink, but it remains uncertain whether it was due to the increase in the source or the decrease in the sink. The GOE substantially affected the climate,biological evolution, and biogeochemical cycles, but the specific processes remain elusive. In consideration of the current progress, we propose four aspects for future explorations, including the construction of geological and geochemical proxies for extremely low atmospheric oxygen content(pO), how the GOE changed the evolutions of Earth’s habitability and the processes in deep Earth, and constraining the mechanism of the GOE by coupling geological events with different time scales.

关键词： Great Oxidation Event Proterozoic Paleoceanography Mantle oxygen fugacity Biogeochemistry

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Correlation of the anisotropic hardening behavior and texture features of cold rolled Zr-4 sheet under uniaxial tension

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Journal of Materials Science & Technology 2022年第24期119卷 111-122页

作者： Huan Liu Siying Deng Shuaifeng Chen Hongwu Song shihong zhang Ben Wang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 11016China State Nuclear Bao Ti Zirconium Industry Company Baoji 721013China

The strongly anisotropic mechanical behaviors commonly observed in Zr-4 sheets typically lead to inferior formability.In this study,the mechanical behavior and texture evolution of a cold-rolled Zr-4 sheet under uniaxial tension in various directions were systematically investigated,and the results showed both anisotropic yielding and hardening behavior in the Zr-4 sheet.The microstructure and texture features revealed by electron backscattered diffraction(EBSD)method indicate that this anisotropic mechanical behavior is closely related to the initial texture and its evolution during plastic deformation.In conjunction with experimental observations,a visco-plastic self-consistent(VPSC)model was employed to quantitatively analyze the relationship between the mechanical anisotropy and the texture features and activation of deformation modes.It was found that the yield anisotropy is affected by the distinct activity of prismaticslip,while the different activities of basalslip and extension twinning(ETW)result in anisotropic hardening.The distinct activation of deformation modes is mainly caused by differences in the evolution of the Schmid factor(SF)and critical resolved shear stress(CRSS)with increasing strain.Additionally,the results prove that the limited twinning activation with a fraction of less than 3%plays a non-negligible role in the hardening behavior during tension along the transverse direction.The latent hardening effect caused by the interaction between prismatic slip and tensile twinning is considered to successfully capture the anisotropic hardening behavior of the Zr-4 sheet.The implementation and insights from the predictions are presented and discussed in this work.

关键词： Zr-4 sheet Anisotropic hardening Texture evolution Deformation modes Twinning

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Controlling dynamic recrystallization via modified LPSO phase morphology and distribution in Mg-Gd-Y-Zn-Zr alloy

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Journal of Magnesium and Alloys 2023年第11期11卷 4218-4234页

作者： Ce Zheng Shuaifeng Chen Ming Cheng shihong zhang Yingju Li Yuansheng Yang Shi-changxu Innovation Center for Advanced Material Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Featured initial microstructures of Mg-11Gd-4Y-2Zn-0.5Zr alloy(wt%) were obtained by adjusting temperatures of solid solution and cooling methods, including island intergranular 18R and 14H LPSO phases with low-density stacking faults, differentially spaced lamellar intragranular 14H-LPSO phases, and network intergranular 18R-LPSO phases with high-density intragranular stacking faults. Effects of these featured LPSO phases and stacking faults on dynamic recrystallization(DRX) behavior were investigated via hot compression. Promoted DRX behavior via particle stimulated nucleation(PSN) is introduced by coexisting intergranular island 18R and 14H LPSO phases and intragranular wide spacing lamellar 14H-LPSO phases, contributing the highest DRX fraction of 42.6%. Conversely, it is found that DRX behavior with network intergranular 18R-LPSO phases and dense intragranular stacking fault is considerably inhibited with the lowest fraction of 22.8%. That is, the restricted DRX due to dislocations pinning by stacking faults overwhelms the enhanced DRX behavior via PSN of island intergranular 18R and 14H LPSO phases. Specially, compared with dense intragranular lamellar 14H-LPSO phases, high-density stacking faults exert a larger inhibition effect on DRX behavior.

关键词： Mg-Gd-Y-Zn-Zr Dynamic recrystallization LPSO phases Particle stimulated nucleation Stacking fault

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物理信息神经网络代理求解燃烧反应动力学

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工程热物理学报 2024年第6期45卷 1872-1881页

作者：张世红张弛王柏森北京航空航天大学航空发动机研究院航空发动机气动热力国家级重点实验室北京100191

现阶段基于神经网络构建化学反应动力学的代理模型被认为是加速燃烧数值计算的重要方法。纯数据驱动神经网络长期存在过于依赖数据采样、鲁棒性和泛化性难以保证等问题。为此,本文在训练化学反应动力学代理模型时引入了质量作用定律、... 详细信息

现阶段基于神经网络构建化学反应动力学的代理模型被认为是加速燃烧数值计算的重要方法。纯数据驱动神经网络长期存在过于依赖数据采样、鲁棒性和泛化性难以保证等问题。为此,本文在训练化学反应动力学代理模型时引入了质量作用定律、质量守恒、能量守恒、元素守恒等物理信息的约束。在零维自燃和二维本生灯火焰的数值计算中,物理信息神经网络在保证2.0~4.7倍加速比的同时,抑制了神经网络代理模型的预测偏差,并且根据输运方程源项误差的理论估计给出了降低代理模型误差、提高模型鲁棒性的相关建议。

关键词：燃烧反应动力学物理信息神经网络源项误差

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Enhanced stability and electrochemical properties of lanthanum and cerium co-modified LiVOPO_(4) cathode materials for Li-ion batteries

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Journal of Rare Earths 2023年第10期41卷 1590-1596,I0005页

作者： Zishan Ahsan Zhenfei Cai Shuai Wang Haichuan Wang Yangzhou Ma Guangsheng Song shihong zhang Weidong Yang Muhammad Imran Cuie Wen Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials Ministry of EducationSchool of Materials Science and EngineeringAnhui University of TechnologyMaanshan243000China School of Metallurgical Engineering Anhui University of TechnologyMaanshan243002China Future Manufacturing Flagship Commonwealth Scientific and Industry Research OrganizationMelbourneVictoria3168Australia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha61413Saudi Arabia School of Engineering RMIT UniversityBundooraVictoria3083Australia

A facile and efficient ball-milling assisted sol-gel synthesis route was developed to prepare triclinic e-LiVOPO_(4)(LVOP)material with lanthanum(La)and cerium(Ce)modification individually as well as simultaneously.An LVOP/LaPO_(4)/CePO_(4)composite cathode material was successfully synthesized and results show that La and Ce co-modification noticeably improves the electrochemical performance by enhancing the high voltage capacity upon cycling,which indicates contributions from the good ionic conductors LaPO_(4)and CePO_(4).The simultaneous La and Ce modification improves the high voltage performance significantly with an increase of 50%in high voltage capacity after 20 cycles compared to pure LVOP.It also shows stabilized cycling perfo rmance with 91%capacity rete ntion after 50 cycles at 0.1 C rate,along with high-rate capability with a capacity of 83.1 mAh/g compared to the pristine sample showing the capacity of 51.6 mAh/g at a high rate of 5C.This can be attributed to the good conductivity of LaPO_(4)and CePO_(4).In addition,the LVOP/LaPO_(4)/CePO_(4)composite and the pristine LVOP give a charge transfer resistance of-105 and-212Ω,respectively,showing much lower impedance due to a combination of La and Ce addition.

关键词： Li-ion bateries ε-LiVOP04 Cathode materials La Ce co-modification Enhanced stability Rare earths

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DP-GH4169合金在Delta工艺中的热变形行为及机制

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稀有金属 2024年第5期48卷 651-659页

作者：张海燕程明胡如夫张士宏赵忠宁波工程学院机械与汽车工程学院浙江宁波315336 中国科学院金属研究所辽宁沈阳110016

相是镍基变形高温合金GH4169合金中主要强化相γ″的稳定相,以δ时效处理后的GH4169(Delta processed GH4169,DP-GH4169)合金为研究对象,通过等温恒应变速率压缩实验,在温度为954~996℃和应变速率为0.001~0.1 s^(-1)的范围内研究了该合... 详细信息

相是镍基变形高温合金GH4169合金中主要强化相γ″的稳定相,以δ时效处理后的GH4169(Delta processed GH4169,DP-GH4169)合金为研究对象,通过等温恒应变速率压缩实验,在温度为954~996℃和应变速率为0.001~0.1 s^(-1)的范围内研究了该合金在Delta工艺中的热变形行为,获得了合金的热变形激活能和应变速率敏感因子,建立了功率耗散图。通过光学显微镜(OM)、透射电镜(TEM)和电子背散射衍射(EBSD)分析了该合金在Delta工艺热变形时的变形机制和微观组织演变机制。结果表明,DP-GH4169合金在Delta工艺热变形中的微观组织演变机制为动态再结晶(DRX)和片层状δ相的球化;变形激活能为332.276 kJ·mol^(-1);片层状δ相的球化行为与晶界滑移机制的相互作用,导致合金在应变速率范围为0.001~0.1 s^(-1)变形时应变速率敏感因子的变化规律不同;基于功率耗散图,DP-GH4169合金在高于980℃变形时,高应变速率更有利于获得细晶;在温度为957~971℃和应变速率为0.001~0.004 s^(-1)的范围内变形时,DP-GH4169合金发生了超塑性变形。

关键词：变形行为 GH4169合金 Delta工艺(DP) 功率耗散图 δ相

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路边一位四车停车装置研究与设计

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机械设计 2024年第1期41卷 140-145页

作者：刘夏张世宏长春大学机械与车辆工程学院吉林长春130022

随着科技的发展,汽车的使用量越来越大,停车难的问题也逐渐凸显出来,尤其是繁华商业街路边停车和小区内路边停车的困难尤为突出,一位停多车的模式是解决现有停车困难问题的关键方法。文中针对现有停车装置的优缺点进行了深入研究,提出... 详细信息

随着科技的发展,汽车的使用量越来越大,停车难的问题也逐渐凸显出来,尤其是繁华商业街路边停车和小区内路边停车的困难尤为突出,一位停多车的模式是解决现有停车困难问题的关键方法。文中针对现有停车装置的优缺点进行了深入研究,提出了一种基于路边停车位的新型一位四车停车装置。基于路边停车位设计了一位四车停车装置,利用现有路边地面上单个停车位的空间进行纵向空间扩展,实现了空一层停车、空二层停车、地面层停车及地下层停车。文中设计的平行四边形翻折机构实现了空间顶层车辆停放、液压驱动链式升降机构实现了空中二层车辆停放、蜗轮蜗杆式自锁升降驱动机构实现了地下车辆的停放和利用地下停车位的顶棚作为路面停车位的托盘实现了地面车辆的停放,自动化系统控制4层停车位的切换实现了4层车辆分别在路面层存取。提出的路边一位四车停车装置充分利用纵向空间,其独特多样的停车方式适用于任何路边停车位,其具有占地面积小、停车数量多、自动化程度高、使用方便及易于管理等优势,为提高路边停车多元化、多样化和简易化提供了一种有效的解决方案。

关键词：路边一位四车停车装置自动化控制

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磁场对钕铁硼表面电沉积Ni镀层性能的影响

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表面技术 2024年第2期53卷 88-96页

作者：项腾飞任黄威周军张世宏安徽工业大学建筑工程学院安徽马鞍山243002 中钢天源股份有限公司安徽马鞍山243002 先进金属材料绿色制备与表面技术教育部重点实验室安徽马鞍山243002

目的研究不同磁场参数对钕铁硼表面电沉积Ni镀层性能的影响。方法以烧结钕铁硼(NdFeB)为基体,采用磁场辅助电沉积方法在其表面镀覆Ni层。利用扫描电镜(SEM)、EDS能谱仪、X射线衍射仪(XRD)分析镀层的表面形貌、元素组成和微观结构,通过... 详细信息

目的研究不同磁场参数对钕铁硼表面电沉积Ni镀层性能的影响。方法以烧结钕铁硼(NdFeB)为基体,采用磁场辅助电沉积方法在其表面镀覆Ni层。利用扫描电镜(SEM)、EDS能谱仪、X射线衍射仪(XRD)分析镀层的表面形貌、元素组成和微观结构,通过电化学工作站对Ni镀层进行耐蚀性能研究。结果施加磁场能显著改善镀层的表面形貌,表面镀层形貌更加均匀致密;试样的耐蚀性显著提高,在平行磁场方向下,当磁场强度为0.07 T时电沉积30 min,所得Ni镀层自腐蚀电位(E_(corr))为–0.193 V,自腐蚀电流密度(J_(corr))为8.305×10^(–7)A·cm^(–2),阻抗值达到3.882×10^(4)Ω·cm^(2),耐蚀性最好。结论施加磁场后,镀层性能得到改善,平行磁场作用下Ni镀层更加均匀细致,其耐蚀性最优,垂直磁场次之,均优于无磁场作用下制备的Ni镀层。

关键词：烧结钕铁硼电沉积磁场强度表面形貌耐蚀性

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Filling Rules of Bevel Gears in the Closed-die Cold Forging

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Journal of Materials Science & Technology 2005年第6期21卷 925-928页

作者： Huamin LIU Liangju HUANG Shenhua YANG shihong zhang Institute of Roll Forging Technology Jilin University Changchun 130025 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The closed-died cold forging technology of the bevel gears used in Jada car was investigated. With the analysis of the strain field and velocity field of the plastic deformation and the endured forces of the dies, the filling rules for the metal were analyzed by the elastic-plastic finite element method （FEM）. The results show that there is a great difference among closed-die cold forging, extrusion and forging, as far as the metal flowing is concerned. The outer addendum cannot be filled completely in the closed-die cold forging of the bevel gears, and the round angle will be formed. But it does not influence the application of the bevel gears. At the beginning, the rigid area is formed in the cavity of the lower die. And then it will move upwards to supply the metal for the gear filling. For the closed-die cold forging of the bevel gears, the force acting on the upper die and the lower die is significantly different.

关键词： Bevel gear Closed-die cold forging FEM Filling rule

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304不锈钢滑动摩擦学行为的分子动力学模拟

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摩擦学学报（中英文） 2024年第4期44卷 551-561页

作者：周安刘秀波王权孟元张世宏中南林业科技大学材料表界面科学与技术湖南省重点实验室湖南长沙410004 安徽工业大学先进金属材料绿色制备与表面技术教育部重点实验室安徽马鞍山243002

采用分子动力学模拟方法研究了压入深度与滑动速度对304不锈钢磨损量、摩擦系数、位错演变及剪切应变的影响.结果表明:在较大的压入深度下平均摩擦系数及位错长度明显较高,导致了更严重的塑性变形;在相同的压入深度下较高滑动速度的摩... 详细信息

采用分子动力学模拟方法研究了压入深度与滑动速度对304不锈钢磨损量、摩擦系数、位错演变及剪切应变的影响.结果表明:在较大的压入深度下平均摩擦系数及位错长度明显较高,导致了更严重的塑性变形;在相同的压入深度下较高滑动速度的摩擦力明显升高而位错长度降低,这是由于高速下不锈钢内部位错形核缺乏持续驱动力,从而减轻了不锈钢的变形.此外滑动摩擦过程中产生的摩擦热促进了内应力的释放,导致离散结构位错、多节点位错及位错锁(环)的形成,从而阻碍位错进一步传播并提高不锈钢抗变形能力.本工作中所计算磨损原子数量几乎与滑动距离呈线性正比,符合经典Archard定律.

关键词： 304不锈钢分子动力学模拟滑动摩擦学行为纳米划痕

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