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34CrNiMo6钢曲轴轴颈感应淬火硬化微观机理

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金属热处理 2024年第1期49卷 242-248页

作者：汪英芝谢波纪超王红霞郑留伟梁伟太原理工大学材料科学与工程学院山西太原030024 山西柴油机工业有限责任公司山西大同037036 太原理工大学分析测试中心山西晋中030600

利用显微硬度计测试了34CrNiMo6钢曲轴轴颈在460、480、500 V淬火电压下,经中频表面感应淬火+300℃回火后的硬度值。利用光学显微镜(OM)、扫描电镜(SEM、EBSD)、X射线衍射分析仪(XRD)观察不同淬火电压下轴颈组织演变,研究了组织演变对... 详细信息

利用显微硬度计测试了34CrNiMo6钢曲轴轴颈在460、480、500 V淬火电压下,经中频表面感应淬火+300℃回火后的硬度值。利用光学显微镜(OM)、扫描电镜(SEM、EBSD)、X射线衍射分析仪(XRD)观察不同淬火电压下轴颈组织演变,研究了组织演变对曲轴钢表面硬度的影响机制。结果表明,在460、480、500 V电压感应淬火后,各试样表层硬度均有明显提高,并在次表层硬度达到最大。这主要是由于经不同电压表面感应淬火后,各试样不同区域组织不同,相的含量不同、位错密度不同造成的。根据组织及硬度分布的不同,轴颈由表及里可分为淬硬层、过渡层及心部。淬硬层深度、硬度与淬火电压呈正相关。

关键词： 34CrNiMo6钢曲轴感应淬火显微组织硬度

Crystal structures and thermal expansion properties of Y_(2-x)Er_xMo_4O_(15) (x=0.0-2.0) solid solutions

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Rare Metals 2007年第5期26卷 426-434页

作者： YU Zhouxiang CHEN Dongfeng WANG Hui PENG jie CHENG yingzhi WU Meimei HU Zhongbo China Institute of Atomic Energy Beijing 102413 China College of Chemistly and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A new series of rare earth compounds,Y2-xErxMo4O15 （x=0.0-2.0）,were synthesized and their structures were determined by powder X-ray diffraction （XRD）. Rietveld analysis of XRD patterns reveals that the compounds of this series crystallize in monoclinic system with space group P21/c. The lattice parameters a,b,c,β and the unit cell volume V de-crease linearly with increasing Er content. The thermal expansion properties of these compounds were studied under high-temperature XRD. Positive thermal expansions of compounds Y2-xErxMo4O15 are found to be anisotropic along the three crystallographic directions where a and c axes expand while b axis contracts in the whole temperature range. By analysis of data,the expansion of weak band Mo2-O14 with rising temperature should be responsible for positive thermal expansion.

关键词： thermal expansion crystal structure molybdate XRD

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张照与衍圣公家族的姻亲关系及相关书事考论

聊城大学学报（社会科学版） 2024年第2期 47-55页

作者：梁骥淮阴师范学院美术学院江苏淮安223001

张照女儿张应芝适孔子六十九代孙孔继涑,子张应田娶孔子七十一代女孙孔德荣,张家与衍圣公家族结成姻亲关系。虽然张应芝因病早殇,孔继涑仍然与张家保持密切联系,向张照学习笔法,请张照为其祖父孔毓圻遗集作序。张照逝后将张照书迹入石成... 详细信息

张照女儿张应芝适孔子六十九代孙孔继涑,子张应田娶孔子七十一代女孙孔德荣,张家与衍圣公家族结成姻亲关系。虽然张应芝因病早殇,孔继涑仍然与张家保持密切联系,向张照学习笔法,请张照为其祖父孔毓圻遗集作序。张照逝后将张照书迹入石成帖,同时搜集张照书法题跋资料成《天瓶斋书画题跋》。孔继涑保存了大量的张照书学文献,为其书名的传播发挥了重要作用。张孔两家的姻亲关系,也得到了乾隆皇帝及皇后的关注。乾隆临幸阙里,命孔继涑以张照字体作书。张应田妻孔德荣三次朝见太后。乾隆召见张照孙张鑑时,垂问孔德荣近况,这些都是张、孔两家姻亲对其家族子弟带来的影响。

关键词：张照衍圣公姻亲书法乾隆

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基于灰色预测的驾驶员-汽车系统侧翻预测

中国机械工程 2018年第9期29卷 1009-1016页

作者：赵又群金颖智季林南京航空航天大学能源与动力学院南京210016

为了保证高速行车安全性,研究了基于预瞄-预测模型的汽车侧翻评价指标估计问题,提出了一种基于预瞄-预测驾驶员模型的侧翻预测方法。以高重心汽车为研究对象,建立了三自由度汽车模型和预瞄驾驶员模型;基于预瞄-跟随理论和灰色预测理论,... 详细信息

为了保证高速行车安全性,研究了基于预瞄-预测模型的汽车侧翻评价指标估计问题,提出了一种基于预瞄-预测驾驶员模型的侧翻预测方法。以高重心汽车为研究对象,建立了三自由度汽车模型和预瞄驾驶员模型;基于预瞄-跟随理论和灰色预测理论,搭建了预瞄-预测驾驶员模型;根据汽车侧翻的机理提出了能反映侧翻情况的指标——横向载荷转移率,并在此基础上提出了汽车侧翻指标估计-预测模型;基于主动转向控制策略和汽车侧翻指标估计-预测模型构建了汽车侧翻预测系统,并进行了不同工况下的仿真分析,从而验证了侧翻预测系统的有效性。

关键词：侧翻横向载荷转移率驾驶员建模灰色预测

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水压光面爆破在济莱高铁寨山隧道中的应用

中国高新科技 2024年第4期 73-75页

作者：秦晓鹏梁英智赵松壮王树栋济南轨道交通集团有限公司山东济南250000 济南交通发展投资有限公司山东济南250000

水压光面爆破是近几年在隧道爆破施工中应用的技术,该技术在济莱高铁寨山隧道开挖过程中进行了广泛应用。通过对比普通光面爆破与水压光面爆破的技术指标与经济效益,该技术可提高整个隧道爆破施工中的效率,对隧道的超欠挖实现了有效控制... 详细信息

水压光面爆破是近几年在隧道爆破施工中应用的技术,该技术在济莱高铁寨山隧道开挖过程中进行了广泛应用。通过对比普通光面爆破与水压光面爆破的技术指标与经济效益,该技术可提高整个隧道爆破施工中的效率,对隧道的超欠挖实现了有效控制,节省了施工成本,提高了施工效率,最大限度地降低了爆破粉尘和噪声的产生,改善了工人作业的环境,对周边环境的影响降到了最低,确保了施工进度,实现了更高的经济效益。

关键词：水压光面爆破隧道超欠挖环境影响经济效益

Oxidation State as a Descriptor in Oxygen Reduction Electrocatalysis

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CCS Chemistry 2022年第11期4卷 3587-3598页

作者： Ning Qin Sicen Yu Zongwei ji Yanfang Wang yingzhi Li Shuai Gu Qingmeng Gan Zhenyu Wang Zhiqiang Li Guangfu Luo Kaili Zhang Zhouguang Lu Department of Materials Science and Engineering Shenzhen Key Laboratory of Interfacial Science and Engineering of MaterialsSouthern University of Science and TechnologyShenzhen 518055 Department of Mechanical Engineering City University of Hong KongKowloonHong Kong 999077 Guangdong Provincial Key Laboratory of Computational Science and Material Design Southern University of Science and TechnologyShenzhen 518055

Electrocatalysts for the oxygen reduction reaction(ORR)are critically important in the development of fuel cells and metal-air *** research interests have been devoted to improving the electrocatalytic performance by tuning the morphology and defect-active ***,we demonstrate that the oxidation state can also serve as an effective strategy for designingORR *** of silver with gradient chemical valence from zero valence to trivalence were successfully *** oxidation states were evaluated by cryo-X-ray photoelectron spectroscopy,X-ray absorptionfinestructure,and electron paramagnetic resonance *** the first time,our results demonstrated that the electrocatalytic activities of silver species can be improved by increasing their valence,conforming the orderofAg

关键词： silver oxides high valence oxygen reduction oxidation state electrocatalysis

Potential targets for protecting against hippocampal cell apoptosis after transient cerebral ischemiareperfusion injury in aged rats

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Neural Regeneration Research 2014年第11期9卷 1122-1128页

作者： Xiangyu ji Li'na Zhang Ran Liu yingzhi Liu jianfang Song He Dong Yanfang jia Zangong Zhou Department of Anesthesiology Affiliated Hospital of Qingdao University Department of Anesthesiology Qingdao Municipal Hospital Department of General Surgery Affiliated Hospital of Qingdao University

Mitochondria play an important role in neuronal apoptosis caused by cerebral ischemia, and the role is mediated by the expression of mitochondrial proteins. This study investigated the involvement of mitochondrial proteins in hippocampal cell apoptosis after transient cerebral ischemia-reperfusion injury in aged rats using a comparative proteomics strategy. Our exper-imental results show that the aged rat brain is sensitive to ischemia-reperfusion injury and that transient ischemia led to cell apoptosis in the hippocampus and changes in memory and cognition of aged rats. Differential proteomics analysis suggested that this phenomenon may be mediated by mitochondrial proteins associated with energy metabolism and apoptosis in aged rats. This study provides potential drug targets for the treatment of transient cerebral isch-emia-reperfusion injury.

关键词： nerve regeneration cerebral ischemia reperfusion injury hippocampus cognitivefunction apoptosis mitochondria differential proteomics rats aged neural regeneration

Effects of Exposure Conditions on the Spectral Characteristics of Uniform Fiber Bragg Gratings

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The Journal of China Universities of Posts and Telecommunications 1999年第1期6卷 12-15,78页

作者： Manuscript receivedBai Baohua Sun yingzhi and Qian Ying (Department of Telecommunication Engineering, Changchun Institute of Posts and Telecommunications, Changchun 130012, P R. China)ji Yuefeng and Lin jintong(Institute of Telecommunication Engineering,

During the fabrication of uniform fiber gratings, the exposure conditions have effects on the reflection and transmission spectral characteristics of gratings. The reflectivity of fiber gratirgs is nonlinear as a function of both the exposure fluency and exposure time. The shorter-wavelength loss, the change of the bandwidth and the shift of the center wavelength are also investigated in this paper.

关键词： fiber Bragg grating refractive-index reflective characteristics fluency

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《祖堂集》校读札记一则--“王莽则位”辨

宗教学研究 2008年第1期 176-177页

作者：梁嘤之四川大学文新学院汉语言文字学硕士研究生

本文从文献、语词、字体结构等角度,对《祖堂集》中"则位"这一说法作了考证,疑该说乃写本在传抄中因形近而出现的讹误。

关键词：祖堂集则位即位