112 research outputs found

    行星齿轮减速器可靠性优化设计研究

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    为了减轻行星齿轮减速器的重量,提高承载效率,取行星齿轮减速器的太阳轮和齿圈的齿数、模数和齿宽为设计变量,以减速器体积最小化为优化目标,利用MATlAb优化工具箱对行星齿轮减速器进行优化设计计算。计算结果表明,采用可靠性优化设计方法可以缩短设计周期并减小体积

    Romax软件在行星齿轮机构中的应用

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    本文介绍了四档拉维娜行星齿轮机构换挡工作规律和速比计算。在rOMAX软件中建立四档拉维娜行星齿轮机构的虚拟样机模型,仿真分析得到了拉威娜齿轮机构各档的输出转速,与理论计算值完全吻合,传动比的一致性也同时得到验证

    知情交易概率能够测度信息风险吗?——以并购公告前后的信息效应为例

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    本文利用2004~2008年的86起并购重组事件考察了并购公告前后信息结构的变化。发现在并购公告之前,存在显著的信息泄漏。本文检验了并购公告前后知情交易概率(PIN)的变化,发现并购公告前的PIN低于并购公告后的PIN,从而表明PIN无法准确地反映信息不对称程度,因而PIN并不是衡量信息不对称的很好指标。另外,买卖价差在并购公告之前逐渐上升,并购公告之后逐渐下降,因此,买卖价差能够较好地反映信息结构的变化

    基于工况风险评估的叉车门架多工况拓扑优化

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    以某3T型内燃叉车的标准门架为例,实现了典型工况下门架系统的整体非线性有限元分析;基于工况数据(工作时长、结构应力及形变位移),提出了工况风险评估方法及工况风险指标(RI)的概念;依据工况风险指标,提出了一种分配多工况拓扑优化权重系数的方法;采用折中规划法,以多工况下门架加权柔度最小为目标函数对门架结构进行拓扑优化;根据优化结果对门架结构进行改进设计,并进行了有限元分析。研究结果表明:风险评估法较传统平均分配法能得到更优的目标值;与原门架结构相比,新门架结构在3种典型工况下的最大应力分别减小10.05%、10.25%和1.58%,最大位移分别减小13.17%、12.93%和8.28%,质量减小7 kg。福建省科技重大专项(2016HZ0001-9

    Study on Tomato Transformation with Human Keratinocyte Growth Factor-1

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    人角质细胞生长因子在组织的损伤修复中起着重要的作用.以番茄子叶为外植体,通过根癌农杆菌介导法,将人kgf-1导入番茄中,共获得12株独立的抗性转化植株,PCr和dnA斑点杂交结果表明:kgf-1基因整合入番茄基因组中,为获得植物源表达的kgf-1蛋白打下了基础.Keratinocyte growth factor plays an important role in the tissue damage repair.Using sterile tomato cotyledons as explants,the human KGF-1 gene had been introduced into the tomato genome by Agrobacterium-mediated transformation method.As a result,a total of 12 independent putative transgenic tomato plantlets were obtained.The results of PCR and DNA dot-blot hybridization showed that KGF-1 gene was integrated into the tomato genome.This work has laid a foundation for further studies on the development of KGF-1 proteins expressed in tomatoes.福建省自然科学基金(2010J01240

    Expression of Modified H5N1 Avian Influenza Virus M2 Gene and the Recombinant M2 Protein Immunogenicity Assay

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    禽流感的发生不仅会造成禽类的大量死亡,而且也严重地威胁着人类健康,接种疫苗是控制禽流感发生的主要措施之一.M2基因的保守性使其成为基因工程亚单位疫苗的目标抗原.本研究将M2基因的跨膜区删除后,构建原核表达载体PET32A-△M 2,IPTg诱导后,收获的细菌总蛋白SdS-PAgE电泳结果表明修饰的M2基因在原核表达系统中得到高效表达,表达蛋白以可溶性形式存在,WESTErn杂交和动物免疫结果表明重组蛋白具有抗原性和免疫原性.本研究结果为利用M2重组蛋白开发具有交叉保护作用的禽流感疫苗奠定了基础.The present vaccination is one of main strategy for control of avian influenza virus that critically threatened human health.Recent investigations of subunit component vaccine focused on M2 gene because M2 gene possessed a highly structurally conserved property among influenza viral strain.In this study,the recombinants prokaryotic expression plasmid pET32a-△ M2 harboring the deletion of the transmembrane segment of M2 gene was constructed.SDS-PAGE electrophoresis showed that modified M2 gene was highly expressed as fusion protein in a soluble form after genetic modified E.coli BL21(DE3) bacteria were induced with IPTG.The fusion protein of M2 possessed antigenicity and immunogenicity properties by Western Blotting analysis of fusion protein with standard antibody against M2(H5N1) and mouse vaccination of purified fusion protein respectively.The results laid a foundation of further study on the development of cross-protection avian influenza vaccine.福建省科技厅重点项目(2009N0051);福建省教育厅A类科技项目(JA09168

    Electrocatalytic Oxidation of Formic Acid on Pd/Ni Heterostructured Catalyst

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    通过两步还原法制备了Pd/Ni双金属催化剂.由于金属Pd原子在先行还原的Ni纳米粒子表面的外延生长以及其在Ni表面及Pd表面生长表现出的吉布斯自由能差异,最终导致了异结构Pd/Ni纳米粒子的形成.高分辨电子透射显微镜结果证实了异结构的存在,然而X射线衍射测量表明Pd/Ni纳米粒子具有类似于Pd的面心立方结构.制备的Pd/Ni纳米粒子与同等条件下合成的Pd纳米粒子相比对甲酸氧化呈现了更高的电催化活性,而且电催化稳定性也要明显优于纯Pd纳米粒子,证明Pd/Ni双金属催化剂是可选的直接甲酸燃料电池阳极催化剂.双金属催化剂对甲酸氧化电催化活性和稳定性增强可能是Ni原子的修饰改变了Pd粒子表面配位不饱和原子的电子结构所致.A Pd/Ni bimetallic nanostructured electrocatalyst was fabricated via a two-step reduction route. Owing to an epitaxial growth of Pd atoms on the surface of Ni nanoparticles, heterostructured Pd/Ni nanocomposites were formed and verified by high resolution transmission electron microscopy combined with energy-dispersion X-ray spectroscopy. X-ray diffraction confirmed that the as-prepared Pd/Ni nanocomposites possessed a single face-centered-cubic (fcc) Pd structure, probably due to a weaker diffraction intensity of metallic Ni and/or overlapping by that of Pd. The intrinsic catalytic activity on the Pd/Ni is higher than that on the Pd. Moreover, the durability of formic acid oxidation on the Pd/Ni was much enhanced over the Pd nanoparticles. The change in electronic structure of the surface coordination unsaturated Pd atoms and the possible dissolution of Ni species from the Pd/Ni heterostructure may account for such an improved durability for formic acid oxidation.This work was supported by the National Basic Research Program of China (973 Program) (No. 2012CB932800), the Natural Science Foundation of China (No. 21073219), Shanghai Science and Technology Committee (No. 11DZ1200400) and the Knowledge Innovation Engineering of the CAS (No. 12406, 124091231).This work was supported by the National Basic Research Program of China (973 Program) (No. 2012CB932800), the Natural Science Foundation of China (No. 21073219), Shanghai Science and Technology Committee (No. 11DZ1200400) and the Knowledge Innovation Engineering of the CAS (No. 12406, 124091231).作者联系地址:1. 中国科学院上海高等研究院,上海 201210;2. 中国科学院研究生院,北京 100039Author's Address: 1. Shanghai Advanced Research Institute, Chinese Academy of Sciences CAS, Shanghai 201210, China; 2. Graduate School of the CAS, Beijing 100039, China通讯作者E-mail:[email protected] & [email protected]

    侵害名誉权的精神损害赔偿研究

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    人的权利是人类追求的目标之一。人的权利应当得到尊重和保护。名誉权作为人格权利之一,已受到了我国立法机关和司法机关的高度重视,侵害名誉权的精神损害赔偿法律制度已得到了初步的建设。本文拟从精神损害赔偿这一角度谈谈对名誉权的保护。 全文具体内容安排如下: 第一章.名誉权的基本理论部分。介绍了有关名誉问题的几种说法,认为名誉是一个主客观相结合的概念。论述了名誉权的概念、特征,阐述了公民死亡以后名誉保护与名誉权的存留之间的关系,最后把名誉权和容易与之相混淆的荣誉权、肖像权作了比较。 第二章.精神损害赔偿。阐述了精神损害不包括精神利益的损失,以及法人不可能产生因侵权行为而造成的精神损害。接着,回顾了...学位:法学硕士院系专业:法学院法律系_法学学号:X199908025

    Protective effects of icariin extracted from epimedii herba on fetal rat hippocampal neurons

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    published_or_final_versionBiological SciencesMasterMaster of Philosoph
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