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International Journal of Minerals,Metallurgy and Materials 2016年第3期23卷 303-313页

作者： Wan-song Li Hong-ye Gao zhong-yi Li Hideharu Nakashima Satoshi Hata Wen-huai tian School of Materials Science and Engineering University of Science and Technology Beijing Interdisciplinary Graduate School of Engineering Sciences Kyushu University

We present a study concerning Fe-0. 176C-1.31Si-1.58Mn-0.26Al-0.3Cr （wt%） steel subjected to a quenching and partitioning （Q＆P） process. The results of scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and tensile tests demon- strate that the microstructures primarily consist of lath martensite, retained austenite, lower bainite （LB）, and a small amount of tempered martensite; moreover, few twin austenite grains were observed. In the microstrucmre, three types of retained austenite with different sizes and morphologies were observed： blocky retained austenite （-300 nm in width）, film-like retained austenite （80-120 nm in width）, and ul- tra-fine film-like retained austenite （30-40 nm in width）. Because of the effect of the retained austenite/martensite/LB triplex microstructure, the specimens prepared using different quenching temperatures exhibit high ultimate tensile strength and yield strength. Furthermore, the strength effect of LB can partially counteract the decreasing strength effect of martensite. The formation of LB substantially reduces the amount of retained austenite. Analyses of the retained austenite and the amount of blocky retained austenite indicated that the carbon content is critical to the total elongation of Q＆P steel.

关键词： low-carbon steel quenching partitioning retained austenite rnicrostructure mechanical properties

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桥梁承台基坑开挖对临近桥梁结构影响研究

城市道桥与防洪 2024年第9期 124-127,140,M0013页

作者：王建李众赵恺姚海川陈现鹏田德身郭屹赵鑫北京市政建设集团有限责任公司北京市100079 北京市公联公路联络线有限责任公司北京市100081 北京工业大学北京市100124

近年来为解决城市交通拥堵问题,城市高架快速路网建设发展迅速同时桥梁近接施工工程日益增多,基坑开挖对临近既有桥梁的影响成为基坑施工关注的重要问题。利用ABAQUS有限元分析软件结合某新建桥梁上跨轨道交通桥梁工程案例,建立了二维... 详细信息

近年来为解决城市交通拥堵问题,城市高架快速路网建设发展迅速同时桥梁近接施工工程日益增多,基坑开挖对临近既有桥梁的影响成为基坑施工关注的重要问题。利用ABAQUS有限元分析软件结合某新建桥梁上跨轨道交通桥梁工程案例,建立了二维数值分析模型,重点分析了新建桥梁承台基坑开挖支护对周边场地地表变形和既有桥梁结构变形的影响。研究表明:近接既有桥梁结构的新建桥梁承台基坑开挖施工对周边土层的影响主要原因是开挖施工过程引起地表沉降,地表沉降量在基坑两侧呈非对称分布;承台基坑开挖对既有桥梁的水平向和竖向变形都在安全可控范围内,主要影响既有桥梁的水平向变形。

关键词：承台基础近接施工既有桥梁结构基坑开挖和支护

Evaluation of WRF Model Hydrometeors Based on TMI Observations Using an Indirect Method

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Atmospheric and Oceanic Science Letters 2012年第1期5卷 32-37页

作者： FU Yun-Fei HENG Zhi-Wei LI tian-yi SHEN zhong-Ping wang Yu School of Earth and Space Sciences University of Science and Technolo~ of China Hefei 230026 China Shanghai Climate Center Shanghai 200030 China

Using a microwave radiative transfer （MWRT） model with microwave brightness temperatures （TBs） observed from the Tropical Rainfall Measuring Mission （TRMM） Microwave Imager （TMI）, an indirect approach evaluated hydrometeors generated from the Weather Research and Forecasting （WRY） model in the process of CHABA typhoon in August 2004. This study compares the simulated TBs generated from the microwave radioactive transfer model connected to the WRF model with the observed TBs derived from TMI and analyzes the differences between these TBs. The results indicate that the WRF model underestimates the amount and area of liquid and ice hydrometeors inside the typhoon center. The results also indicate relatively better agreement between the simulated and the observed TBs in the vertical polarization than in the horizontal polarization.

关键词： WRF hydrometeors TMI microwave radiative transfer

Effect of axial static magnetic field on cleanliness and microstructure in magnetically controlled electroslag remelted bearing steel

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Journal of Iron and Steel Research International 2021年第12期28卷 1562-1573页

作者： Qiang Li Zhi-bin Xia yi-feng Guo Zhe Shen tian-xiang Zheng Biao Ding Yun-bo zhong School of Materials Science and Engineering State Key Laboratory of Advanced Special SteelShanghai Key Laboratory of Advanced FerrometallurgyShanghai UniversityShanghai200444China

The effect of the axial static magnetic field(ASMF)on cleanliness and microstructure in magnetically controlled electroslag remelted GCr15 bearing steel ingots was investigated *** results show that a magnetically controlled spin-vibration induced by the interaction of the ASMFs and the remelting current exists at the consumable electrode tip,resulting in thinner liquid melt film and smaller *** the increase in magnetic flux density,the optimization effect of ASMFs on electroslag remelting process increases and reaches the peak with a 40 mT ASMF,then *** cleanliness of the ingots was improved,and the count of inclusions larger than 5μm was *** microstructure of the ingots processed with a 40 mT ASMF was significantly *** depth of the metallic molten pool was reduced from 45.2 to 17.5 mm with the application of 40 mT *** tensile strength,impact toughness,and Rockwell hardness of the ingots obtained under the 40 mT ASMF were significantly *** mechanisms of the spin-vibration occurring at the electrode tip end were interpreted in detail to elucidate the effect of ASMFs.

关键词： Magnetically controlled electroslag remelting Axial static magnetic field Inclusion removal Molten pool Alternating Lorentz force Cleanliness GCr15 bearing steel

Topological electronic states in HfRuP family superconductors

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npj Computational Materials 2019年第1期5卷 88-93页

作者： Yuting Qian Simin Nie Changjiang yi Lingyuan Kong Chen Fang tian Qian Hong Ding youguo Shi Zhijun wang Hongming Weng zhong Fang Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Department of Materials Science and Engineering Stanford UniversityStanfordCA 94305USA CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing100190China Songshan Lake Materials Laboratory DongguanGuangdong 523808China

Based on the first-principles calculations and experimental measurements,we report that the hexagonal phase of ternary transition metal pnictides TT’X(T=Zr,Hf;T’=Ru;X=P,As),which are well-known noncentrosymmetric superconductors with relatively high transition temperatures,host nontrivial bulk *** the superconducting phase transition,we find that HfRuP belongs to a Weyl semimetal phase with 12 pairs of type-II Weyl points,while ZrRuAs,ZrRuP and HfRuAs belong to a topological crystalline insulating phase with trivial Fu-Kane Z_(2) indices but nontrivial mirror Chern ***-quality single crystal samples of the noncentrosymmetric superconductors with these two different topological states have been obtained and the superconductivity is verified *** wide-range band structures of ZrRuAs have been identified by ARPES and reproduced by theoretical *** with intrinsic superconductivity,the nontrivial topology of the normal state may generate unconventional superconductivity in both bulk and *** findings could largely inspire the experimental searching for possible topological superconductivity in these compounds.

关键词： nontrivial superconductors topological

生物基环氧化天然橡胶形状记忆复合材料的制备与性能

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合成橡胶工业 2024年第3期47卷 233-239页

作者：崔刘富田晓慧元以中孙金煜华东理工大学材料科学与工程学院上海200237

以壳聚糖作为填料、脱蛋白环氧化天然橡胶(ENR)作为基质材料,制备了生物基形状记忆复合材料,通过傅里叶变换红外光谱、原子力显微镜、电子万能试验机等研究了该形状记忆复合材料的微观结构、力学性能及形状记忆性能。结果表明,加入壳聚... 详细信息

以壳聚糖作为填料、脱蛋白环氧化天然橡胶(ENR)作为基质材料,制备了生物基形状记忆复合材料,通过傅里叶变换红外光谱、原子力显微镜、电子万能试验机等研究了该形状记忆复合材料的微观结构、力学性能及形状记忆性能。结果表明,加入壳聚糖后ENR的有序结晶相以更小、更均匀的尺寸分散在整个体系中;由于壳聚糖的增强增韧作用,该形状记忆复合材料的耐磨性能增强、力学性能逐渐提高。此外,壳聚糖的加入进一步提高了ENR的形状记忆性能。

关键词：壳聚糖环氧化天然橡胶生物基复合材料形状记忆性能力学性能微观结构结晶性

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地下水年龄及其在含水层封闭性评价中的应用

矿物岩石地球化学通报 2024年第3期43卷 489-501,I0001页

作者：赵雅静黄天明昝朝耀龙吟李义曼张艳祁生文庞忠和中国科学院地质与地球物理研究所北京100029 中国科学院大学地球与行星科学学院北京100049

针对目前地下水年龄和地下水滞留时间概念混用、地下水年龄分类缺乏依据及地下水定年方法复杂多样的问题,本文给出了地下水年龄和地下水滞留时间的严格定义,考虑不同定年方法的测年范围以及人类活动影响程度等因素,进行了地下水年龄的... 详细信息

针对目前地下水年龄和地下水滞留时间概念混用、地下水年龄分类缺乏依据及地下水定年方法复杂多样的问题,本文给出了地下水年龄和地下水滞留时间的严格定义,考虑不同定年方法的测年范围以及人类活动影响程度等因素,进行了地下水年龄的合理分类。本文还总结了已有地下水的定年方法,主要包括物理上的水动力模拟计算方法和化学上的示踪剂方法,提出了不同定年示踪剂存在的主要问题以及定年方法选择的原则。最后以鄂尔多斯高原为例,利用地下水年龄判断含水层封闭性,提出了CO_(2)地质封存工程选址的地下水年龄标准(大于3万年),评价结果表明,除补给区和排泄区外,中部的白垩系地层以下满足CO_(2)相态要求、有连续盖层的绝大多数区域满足CO_(2)地质封存的安全要求。

关键词：地下水年龄地下水定年同位素含水层封闭性 CO_(2)地质封存

Experimental investigation of tubing collar's influence on hydrodynamic behavior of annular duct flow

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Petroleum Science 2022年第5期19卷 2326-2342页

作者： yi-Su Zhou zhong-Wei Huang Zhuang-Zhuang Zhang tian-Wen Jiang Rui-Yue Yang Ming-He Zhang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum ChangpingBeijing 102249China China University of Petroleum(Beijing) ChangpingBeijing 102249China

Tubing collars’influence on hydrodynamic behavior of annular duct flow has been investigated using particle Image Velocity(PIV)*** has become an efficient method for complex transient flows visualization.A water flow loop with two replaceable variable cross-sections(VCS),75-90 mm and 90-110 mm,in a 129 mm inner diameter(ID)pipe was *** whole field of the variable cross-section annulus(VCSA)was visualized,including forward-facing step(FFS),narrow annulus(NA),and backwardfacing step(BFS)*** VCSA ratio and Reynolds(Re)number influence on streamline distribution,velocity distribution,and turbulence intensity were *** showed that the recirculation is easier to form in BFS than FFS flow under the same *** VCSA ratio affects the formation of recirculation zones and the location of the reattachment *** number mainly affects BFS flow by influencing the main velocity component-axial *** turbulence intensity is relatively high in BFS than FFS flow and is larger at y/h>1.0 than y/h<***,the streamwise cohere nt structures reveal that the first two modes are predominant and represent the main characteristics of the flow by proper orthogonal decomposition(POD)method.

关键词： Variable cross-section annulus flow Sudden contraction and expansion Hydrodynamic behavior PIV POD

Effects of Post-weld Heat Treatment on Microstructure, Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

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Acta Metallurgica Sinica(English Letters) 2019年第6期32卷 684-694页

作者： Deng-Kui Zhang Guo-Qing wang Ai-Ping Wu Ji-Guo Shan Yue Zhao tian-yi Zhao Dan-Yang Meng Jian-Ling Song zhong-Ping Zhang Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China China Academy of Launch Vehicle Technology Beijing 100076China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationTsinghua UniversityBeijing 100084China tianjin Long March Launch Vehicle Manufacturing Co. Ltd.Tianjin 300462China

In as-welded state,each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second *** the post-weld heat treatment,both the amount and the size of the eutectic structure orθphases ***,both the Cu content inα-Al matrix and the microhardness increased to a similar level in each region of the joint,and the tensile strength of the entire joint was greatly ***-weld heat treatment played the role of solid solution strengthening and aging *** the post-weld heat treatment,the weld performance became similar to other regions,but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff *** joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties,and the specimens randomly crack in the weld zone.

关键词： 2219 Aluminum alloy Tungsten inert gas arc welding Post-weld heat treatment Weld reinforcement Digital image correlation technique

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多指标评价阳春砂不同部位的差异性

中国中药杂志 2024年第5期49卷 1217-1224页

作者：黄贵发罗毓钟文峰陈清怡邓成程莫日江林伟雄田清清广东一方制药有限公司广东佛山528244 湖南一方天江药业有限公司湖南常德415000

为研究阳春砂种仁和果壳的质量差异,探讨砂仁去壳使用的合理性,测定原儿茶酸、香草酸、表儿茶素、槲皮苷、挥发油、水浸出物、醇浸出物含量,并采用DPPH、ABTS和羟自由基法评价种仁和果壳的抗氧化活性。以正交偏最小二乘法判别分析(OPLS-... 详细信息

为研究阳春砂种仁和果壳的质量差异,探讨砂仁去壳使用的合理性,测定原儿茶酸、香草酸、表儿茶素、槲皮苷、挥发油、水浸出物、醇浸出物含量,并采用DPPH、ABTS和羟自由基法评价种仁和果壳的抗氧化活性。以正交偏最小二乘法判别分析(OPLS-DA)和层次分析(AHP)结合熵权法评价种仁和果壳的质量差异。10个指标在种仁和果壳中均有显著性差异(P<0.05)。表儿茶素、槲皮苷、挥发油在种仁中含量更高;原儿茶酸、香草酸、水浸出物和醇浸出物含量在果壳中含量更高。种仁在DPPH和ABTS自由基上表现更强的清除能力,果壳在羟自由基上表现更好的清除效果。OPLS-DA结果表明种仁和果壳有明显的区分度,且变量投影重要性指标(VIP)筛选出挥发油、水浸出物、DPPH自由基清除率、槲皮苷、ABTS自由基清除率、羟自由基清除率和香草酸为主要差异指标。以AHP法结合熵权法计算得到的综合得分表明种仁质量更优。总体而言,阳春砂种仁质量更佳,但果壳中存在优势成分且有一定的抗氧化功效,故建议砂仁一定程度带壳使用,或将果壳进行其他的开发利用。

关键词：阳春砂不同部位含量测定抗氧化活性综合评价