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Interface characteristics between TiN and matrix and their effect on solidification structure

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Journal of Iron and Steel Research International 2021年第9期28卷 1149-1158页

作者： Tian-peng Qu De-yong Wang Hui-hua Wang Dong hou Jun Tian Shao-yan Hu Li-juan Su Shagang School of Iron and Steel Soochow UniversitySuzhou215021JiangsuChina

Heterogeneous nucleation is an effective way to promote the dispersion and precipitation of second-phase particles in steel and refine the grain size of the solidification *** only refining as-cast structure grain size,but TiN in ferritic stainless steel can also pin grain boundaries and restrain the overgrowth of grains during *** interface characteristics between TiN and heterogeneous phases(high-melting inclusions and ferrite phase)were studied based on the wetting angles between molten steel with different compositions and TiN substrate,and on the matching degree between TiN and ferrite *** was found that,for the molten steel with the same composition,the wetting angle with the TiN substrate was significantly smaller than the contact angles with the other three substrates,while the wetting angle between ferrite phase and TiN was the *** lattice matching was compared among MgAl_(2)O_(4),TiN andδmatrix by means of a high-resolution transmission electron microscope,which revealed that a coherent or semi-coherent interface was formed between the crystal plane(400)of MgAl_(2)O_(4)and the crystal plane(200)of TiN,as well as between the crystal plane(200)of TiN and the crystal plane(110)ofδmatrix,with a lattice misfit of 5.1%and 3.4%,***,these two characteristics between TiN and ferrite phase were both explained from the perspective of interfacial *** microstructure refinement mechanism from high temperature to room temperature can be better reflected by the proposed wetting–lattice misfit theory.

关键词： TiN Heterogeneous nucleation Interfacial wetting Lattice matching Grain refinement

Accumulation of glycolipids in wheat grain and their role in hardness during grain development

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The Crop Journal 2019年第1期7卷 19-29页

作者： Haixia Qin Dongyun Ma Xin Huang Jie Zhang Wan Sun Gege hou Chenyang Wang Tiancai Guo National Engineering Research Center for Wheat College of Agronomy Henan Agricultural University The National Key Laboratory of Wheat and Maize Crop Science Henan Agricultural University College of Food Science and Technology Henan University of Technology

Grain hardness is an important parameter for wheat quality. To understand the role of glycolipids in the formation of grain hardness, the glycolipid contents in wholegrain wheat flour and the starch granule surfaces of oven-dried and freeze-dried hard and soft wheat grain were analyzed. Changes in endosperm structure and amyloplast membrane integrity during grain development were also examined by electron microscopy. The monogalactosyldigylcerol(MGDG) and digalactosyldigylcerol(DGDG) contents of the starch surface were significantly higher in soft wheat than in hard wheat, regardless of the drying method or developmental stage. Throughout grain development, MGDG content was significantly higher in the starch surface of freeze-dried hard wheat than in the starch surface of oven-dried hard wheat. In contrast, the MGDG content of the starch surface was significantly higher in freeze-dried soft grain at 14 and 35 days after anthesis. No significant difference was observed in puroindoline protein(pin) accumulation in wholegrain flour from wheat that was dried using the two methods, whereas pin accumulation on the starch surface of freeze-dried grain was lower than that on the starch surface of oven-dried *** gap between the amyloplast membrane and starch granules was larger in hard wheat than in soft wheat, as shown by transmission electron microscopy. For the same wheat cultivar, this gap was larger for oven-dried than for freeze-dried grain. The content of polar lipids in the starch surface was closely related to grain hardness, and the breakdown of the amyloplast membrane may determine the location of polar lipids on the starch surface.

关键词： Amyloplast membrane Endosperm microstructure Grain hardness Polar lipid Wheat

冲击波作用下LY12铝合金结构毁伤的数值模拟

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爆炸与冲击 2012年第5期32卷 470-474页

作者：侯日立周平彭建祥空军第一航空学院河南信阳464000 中国工程物理研究院流体物理研究所四川绵阳621900

针对冲击波作用下的结构毁伤判据问题,利用LS-DYNA软件,对LY12铝合金平板结构的损伤过程进行了数值模拟。讨论了冲击波超压、正压作用时间、材料屈服强度和结构自振频率等因素对结构破坏的影响规律,提出了一个以超压为函数,以正压作用... 详细信息

针对冲击波作用下的结构毁伤判据问题,利用LS-DYNA软件,对LY12铝合金平板结构的损伤过程进行了数值模拟。讨论了冲击波超压、正压作用时间、材料屈服强度和结构自振频率等因素对结构破坏的影响规律,提出了一个以超压为函数,以正压作用时间、材料屈服强度和结构自振频率为参量的破坏判据,与实验结果比较,该判据吻合程度较高。

关键词：固体力学结构毁伤 LS-DYNA LY12铝合金冲击波

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粉煤灰中灰颗粒的摩擦带电特征

煤炭学报 2007年第7期32卷 757-761页

作者：侯新凯徐品晶徐德龙刘辉杨圣玮曾汉侯西安建筑科技大学材料科学与工程学院陕西西安710055

利用电位差计配合法拉第圆筒测量2种材料的摩擦电势差及电性符号,对10种材料进行了摩擦带电研究,确定了它们的摩擦静电序列为Pb,Zn,A l,Fe,C,Mn,Cu,SiC,Ag,粉煤灰;选出了Mn,Cu,SiC,Ag四种作为粉煤灰摩擦带电电选机的荷电摩擦材料.用0.5 ... 详细信息

利用电位差计配合法拉第圆筒测量2种材料的摩擦电势差及电性符号,对10种材料进行了摩擦带电研究,确定了它们的摩擦静电序列为Pb,Zn,A l,Fe,C,Mn,Cu,SiC,Ag,粉煤灰;选出了Mn,Cu,SiC,Ag四种作为粉煤灰摩擦带电电选机的荷电摩擦材料.用0.5 MPa除水压缩空气在铁管中进行气力输送摩擦带电试验,研究了气体流速、管道形式和长度、以及摩擦管道内固气比等因素对粉煤灰摩擦带电量的影响,增大气体流速能显著提高粉煤灰的带电量,而管道长度对灰颗粒的荷质比影响不大.

关键词：粉煤灰电选摩擦静电序列碳粉荷质比气力输送摩擦带电

Influence of Different Connection Types on Mechanical Behavior of Girder Trusses

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Journal of Bioresources and Bioproducts 2019年第2期4卷 89-98页

作者： Zeli QUE Tongyu hou Yifan GAO Qicheng TENG Qiuyun CHEN Changju WANG Cheng CHANG Department of Wooden Structure Construction Engineering Nanjing Forestry UniversityNanjing 210037China

The static test of two single light wood trusses and two girder trusses were carried out to explore theperformance enhancement effect of girder trusses and the influence of different connection types on the mechanicalbehavior, which was studied through the comparison of the test results of four trusses. It is found that the girder trussescan show better load-carrying capacity and anti-deforming ability compared with which simply increases the cross-sectionsize of the members. Because of the advantage of the connection materials and the non-fastening connection mechanism,the wood pin-connected truss has more ultimate bearing capacity which is 2.6 times of single truss, and better deformationresistance which is only 66.2% of the nailed one’s creep value.

关键词： girder truss multiple combination connection node design static load test wood pin

垃圾填埋场渗滤液灌溉及覆土土质对填埋场氧化亚氮释放的影响

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应用生态学报 2008年第7期19卷 1591-1596页

作者：何品晶陈淼张后虎邵立明污染控制与资源化研究国家重点实验室长江水环境教育部重点实验室同济大学环境科学与工程学院上海200092

采用静态箱法,现场监测黏土和砂土覆盖层生活垃圾填埋场N2O释放通量的春夏季节及昼夜变化,研究渗滤液灌溉、覆土土质对填埋场N2O释放的影响.结果表明:砂土和黏土覆盖层填埋场N2O夏季的释放通量均值分别为(242±576)和(591±767)μgN2O-N... 详细信息

采用静态箱法,现场监测黏土和砂土覆盖层生活垃圾填埋场N2O释放通量的春夏季节及昼夜变化,研究渗滤液灌溉、覆土土质对填埋场N2O释放的影响.结果表明:砂土和黏土覆盖层填埋场N2O夏季的释放通量均值分别为(242±576)和(591±767)μgN2O-N·m-2·h-1,是春季[分别为(74.4±314)和(269±335)μgN2O-N·m-2·h-1]的3.2(P>0.05)和2.2倍(P0.05).渗滤液灌溉的砂土覆盖层填埋场N2O春夏两季释放通量均值[(211±460)μgN2O-N·m-2·h-1]仅为无渗滤液灌溉的黏土覆盖层填埋场[(430±605)μgN2O-N·m-2·h-1]的1/2(P>0.05).无论渗滤液灌溉与否,选择贫瘠的砂性覆盖土均有助于减少生活垃圾填埋场N2O释放.

关键词：生活垃圾填埋场 N2O释放通量渗滤液灌溉覆土土质

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三维重建上肢解剖结构的计算机模拟手术

生物医学工程学杂志 2000年第3期17卷 292-294页

作者：陈伟南侯春林苟三怀陆平解放军第一○一医院骨科无锡214044 第二军医大学附属长征医院骨科上海200433 上海医疗器械研究所上海200003

探索三维重建后计算机模拟手术过程的实现。将上肢新鲜标本经 CT扫描后连续切片 ,把 CT图像和大体断面图像同时输入计算机 ,用 Borland C 语言编制三维重建和模拟手术程序 ,建立上肢三维解剖数据模型 ,将临床实际手术操作过程转化为计... 详细信息

探索三维重建后计算机模拟手术过程的实现。将上肢新鲜标本经 CT扫描后连续切片 ,把 CT图像和大体断面图像同时输入计算机 ,用 Borland C 语言编制三维重建和模拟手术程序 ,建立上肢三维解剖数据模型 ,将临床实际手术操作过程转化为计算机可接受的指令 ,实现模拟手术操作。结果表明 :上肢模拟手术可分三段进行 ,手术部位及切口方向可任意选择 ,逐层“切开”并三维显示。因此 ,模拟手术系统可运用于手术方案的设计、选择最佳手术入路、术前模拟手术操作和手术、解剖教学。它能在 5

关键词：上肢解剖结构三维重建计算机模拟手术

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含纵向裂纹飞机内压壁板裂纹扩展行为研究

机械强度 2024年第3期46卷 559-567页

作者：秦剑波王锋吕品侯成范学领中航工业第一飞机设计研究院西安710000 西安交通大学航天航空学院机械结构强度与振动国家重点实验室西安710000

飞机机身壁板裂纹扩展分析是飞机损伤容限设计的重要任务之一。从损伤容限试验与有限元仿真两方面分析了含纵向裂纹飞机机身内压壁板的裂纹扩展行为与剩余强度特征。采用卧式自平衡试验装置对机身壁板施加内压载荷,以分析壁板的损伤容... 详细信息

飞机机身壁板裂纹扩展分析是飞机损伤容限设计的重要任务之一。从损伤容限试验与有限元仿真两方面分析了含纵向裂纹飞机机身内压壁板的裂纹扩展行为与剩余强度特征。采用卧式自平衡试验装置对机身壁板施加内压载荷,以分析壁板的损伤容限特性。并基于有限元方法模拟内压壁板裂纹尖端的应力场分布,基于断裂力学理论计算得到不同长度裂纹的等效应力强度因子和裂纹扩展分析结果。将裂纹扩展结果与试验结果进行对比,证明了分析方法的可行性,为飞机机身内压壁板的损伤容限分析提供参考。

关键词：裂纹扩展损伤容限机身内压壁板应力强度因子

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基于多参数约束的MTD滤波器迭代优化设计

现代雷达 2021年第3期43卷 25-29页

作者：缪惠峰李品侯义东南京电子技术研究所南京210039

动目标检测(MTD)滤波器作为动目标检测雷达的核心部件,其杂波抑制性能将对雷达动目标探测能力起着决定性的影响。文中同时考虑滤波器期望频率响应和信噪比增益,通过构建多参数约束条件,在满足阻带衰减、零陷深度和杂波宽度的条件下,提出... 详细信息

动目标检测(MTD)滤波器作为动目标检测雷达的核心部件,其杂波抑制性能将对雷达动目标探测能力起着决定性的影响。文中同时考虑滤波器期望频率响应和信噪比增益,通过构建多参数约束条件,在满足阻带衰减、零陷深度和杂波宽度的条件下,提出MTD滤波器组的迭代优化设计算法。首先固定滤波器通带宽度,将优化问题转换为二次规划凸问题,再通过二分法迭代求解出满足基本设计条件的最小通带宽度滤波器。设计实例表明:所提算法在不同杂波环境下均具备较高的鲁棒性,尤其当杂波与通带存在重合区域时,所设计的滤波器性能更加优越。

关键词：动目标检测滤波器凸优化多参数约束