掺铁碳化硅陶瓷的制备及其吸波性能

将羰基铁和液态聚碳硅烷(LPCS)反应生成的铁(Fe)溶胶与固态聚碳硅烷(PCS)混合,合成出不同Fe质量分数的PCS先驱体,然后经氧化交联和高温热解制备了不同Fe质量分数的磁性碳化硅陶瓷(Fe/SiC),系统地研究了Fe元素的引入对SiC陶瓷的组成、结构、磁性能和介电性能的影响规律。研究发现,当Fe质量分数小于8.94%时,在热解过程中,Fe元素可以显著促进SiCxOy的分解,生成β-SiC,且随着Fe质量分数的增加,β-SiC的结晶峰越来越强;但随着Fe质量分数继续增加,达11.78%时,则主要生成Fe3Si;Fe/Si C陶瓷均呈铁磁性,其饱和磁化强度随着Fe质量分数的增加而呈指数形式增加;当Fe质量分数为4.19%时Fe/SiC陶瓷在12.4 GHz具有最小的反射损耗,为-9.4 dB,同时低于-5 dB的带宽为2.4 GHz,Fe质量分数为8.94%时,低于-5 dB的带宽则为3.7 GHz,可用作良好的微波吸收材料。国家自然科学基金(51603175);;中央高校基本科研业务费(20720150082)资助项目~

从中国非甲-庚型肝炎病人中克隆到TT病毒样DNA序列

从中国非甲－庚型肝炎病人中克隆到ＴＴ病毒样ＤＮＡ序列张军１杨海杰１苏智军２张奕返２林长青１黄鹤１郭庆１王颖１曾定１夏宁邵１（１厦门大学肿瘤细胞工程国家专业实验室厦门３６１００５２福建省泉州市第一医院泉州３６２０００）肝炎是严重危害我国人民身体健康的疾..

Topology optimization for important components of sausage packaging vision detection equipment

介绍了常用的连续体结构拓扑表达方式和材料插值方法以及求解算法,并比较彼此的优缺点,实现了基于SIMP材料插值方法的最小柔度的数学模型建立,并用优化准则法进行了迭代公式的推导,建立了结构拓扑优化设计的流程图。结合工程实际应用情况,以研发的火腿肠视觉检测设备为对象,采用HyperWorks软件对设备中的重要支撑件进行拓扑优化设计。仿真表明,在满足实际生产强度要求的情况下,零部件体积减少,材料分布更加合理,对零部件实现了轻量化设计,从而为设备的结构改进和优化提供一定的参考依据

Reliability Sensitivity Sequencing of Rotor System with Oil Whip Fault

从可靠性理论的角度出发,根据转子系统发生油膜振荡的规律和油膜振荡故障的特征,应用随机摄动技术和四阶矩技术研究了转子系统油膜振荡故障的可靠性问题,并结合灵敏度技术,提出了转子系统油膜振荡故障的可靠性灵敏度分析方法,给出了可靠性灵敏度的变化规律,研究了随机设计参数改变对转子系统可靠度的影响,并对随机参数对转子系统可靠度的贡献率进行了排序,为转子系统结构的优化设计提供了理论依据

Removing device of ham-sausage appearance on-line vision detecting equipment

本实用新型涉及食品检测设备,具体地说是一种火腿肠外观在线视觉检测设备的剔除装置,该剔除装置倾斜地安装在输送火腿肠的胶辊传送带的上方、包括伺服电机、同步皮带、同步带轮、剔除片及支架,其中支架倾斜地安装在胶辊传送带的上方,同步带轮可转动地安装在支架上、并由安装在支架上的伺服电机驱动,所述同步皮带连接在同步带轮上,在同步皮带上设有剔除片。本实用新型可将经在线检测装置检测存在外观质量问题的火腿肠剔除,自动化控制,反应速度快,作业效率高,剔除速度可达到10根/秒

Reversing device of online visual detection equipment of appearance of ham sausages

本发明涉及食品检测设备，具体地说是一种火腿肠外观在线视觉检测设备的换向装置，包括换向转轮、挡板、支架及伺服电机，其中换向转轮可旋转地安装在支架之间、并通过安装在支架上的伺服电机驱动，在换向转轮的圆周表面均布有多个拨片，相邻拨片之间留有容置火腿肠的空间；所述支架位于火腿肠进入的一侧开有入肠口，在支架之间、换向转轮的一侧设有挡板，该挡板的底端与所述入肠口相对应。本发明通过挡板上的圆锥板与换向转轮之间的间距逐渐减小，可以使火腿肠减速；进入换向装置的火腿肠由换向转轮带动，由沿火腿肠轴向运动改变为垂直火腿肠轴线运动，并可以使火腿肠依次、整齐地落到火腿肠视觉检测设备上，以适于火腿肠的外观视觉检测

Methods and application on research of structural topology optimization

This article reviews the history of the development of topology optimization, also describes main material interpolation schemes of continuum structures including homogenization method, variable density method and variable thickness method. Secondly, introduces two optimization algorithms such as Optimality Criteria and Mathematics Programming, each other's strengths and weaknesses are studied. According to our own practical experience, important support structure was used for topology optimization design based on HyperWorks, the results showed the feasibility of topology optimization. Finally, the prospects of development are proposed from above theory and engineering practice. © 2012 Huazhong Univ of Sci & Tec

Ham sausage sequential conveying device

本实用新型涉及食品加工生产线上的设备,具体地说是一种火腿肠排序输送装置,包括支座、固定板、围板、转盘、驱动机构、刷辊机构及上下水平加速带机构,固定板倾斜地安装在支座上,固定板上设有围板,围板内设有通过驱动机构带动旋转的转盘;在固定板高的一侧安装有刷辊机构及上下水平加速带机构,刷辊机构包括刷辊及第二传动电机,刷辊通过第二传动电机驱动、位于转盘的上方,刷辊及第二传动电机距离转盘的高度可调;上下水平加速带机构包括上下并排设置的两条传送带、分别通过两个传动电机驱动,位于上方的传送带高度可调,两条传送带之间为火腿肠输送通道。本实用新型具有自动化程度高、工作效率高、工作可靠、稳定性好、适应范围广等优点

Electrorheological Characters of Polyaniline Suspensions

将聚苯胺（ＰＡｎ）作为分散粒子，电绝缘油作为分散介质组成电流变流体（ＥＲＦ），研究了电场强度（Ｅ），温度（Ｔ）等因素与ＥＲＦ的静态屈服应力（τＳ）和电流密度（ｉ）的关系．结果表明：τＳ和ｉ随电场强度的变化皆成指数关系（τＳ∝Ｅ０．７，ｉ∝Ｅ２．１８）．而当施加一个恒电压于ＥＲＦ时，由于极化作用ＥＲＦ将发生介质吸收，电流的衰减速度方程可表示为：ｉ＝（Ｅ／Ｒ）ｅｘｐ（－ｔ／ＲＣｄ）Polyaniline (PAn) as the dispersive particles and insulating oil as the dispersive medium, the electrorheological fluid (ERF) is constituted. Relations between the factors of electric field strength ( E ), temperature ( T ) and the static yield stress ( τ S ), current density ( i ) of ERF are investigated. The results show that the changes of τ S and i with electric field intensity have emerged in the exponential relation, i.e, τ S∝E 0.7 , i∝E 2.18 . Otherwise, when exert a constant voltage on ERF, owing to the polarization, the absorption of medium of ERF have taken place. Therefore, the attenuation rate equation of current can be show as i=(E/R) exp (-t/RC d)作者联系地址：湘潭大学化学系Author's Address: Dept. of Chem., Xiangtan Univ., Hunan 41110

Vibration reliability sensitivity analysis of general system with correlation failure modes

The vibration problem of the general system is the main object of research. The material properties and geometry of general system are random parameters because of the manufacturing environment, technical conditions, manufacturing and installation errors, multiphase materials, features and other factors. According to the relation criterion that the difference between the natural frequency and the driving frequency of general systems is not beyond a specific value, the vibration reliability mode and vibration reliability of general systems are defined considering the correlation of the multi-order natural frequency and the random characteristics of structure size and material, and the vibration reliability analysis method for avoiding the resonant is carried out. The second-order joint failure probability is obtained by using the numerical integration method. Based on the reliability design theory and sensitivity analysis method, the vibration reliability sensitivity of the general system with correlation failure modes is extensively discussed and a numerical method for vibration reliability sensitivity design is presented. The variation regularities of vibration reliability sensitivity are obtained and the effects of random parameters on vibration reliability of the general system are studied. The presented method provided the theoretic basis for the reliability design of the general system. A numerical example demonstrated that the proposed method is effective