摘要：本文利用有限元软件DEFORM分析了初始厚度、轧辊温度、压下率及轧制速度对热辊轧制AZ31镁合金冷带材过程接触压力、速度、等效应力、等效应变及等效应变速率分布规律。结果表明:热辊对轧件起到了显著加热作用,轧件温度明显升高,表面与心部温差先增加后减小。接触压力在刚端与塑性交界面急剧增加然后降低,进入塑性变形区再次增加至前滑区降低,从入口端到出口端速度和等效应变呈近似S型增加,等效应力和等效应变速率整体变化趋势是先增加后降低。稳态轧制力随初始厚度、压下率和轧辊温度变化呈近似线性变化,随轧制速度增加呈指数增加。初始厚度增加加大了表面和心部变形速度差及等效应变和应变速率的不均匀分布。相比压下率较小时的压缩变形,随着压下率增加剪切变形量增大,且轧辊热量更易传递至心部,变形更均匀。当轧制速度较大时,表面和心部等效应力、等效应变与等效应变速率差值显著增加,不利于均匀性变形。

摘要：A transient three-dimensional（3 D） model was established to understand the bubble motion in an industrial electrolytic process. An anode with a new design was tested. It incorporates two slots that allow an efficient removal of gas bubbles. The electromagnetic fields were described by solving Maxwell＇s equations. The bubble movement was studied with two-way coupling Euler-Lagrange approach. The interplay of current density and bubble nucleation rate was included. The collision and coalescence of bubbles were considered. Random walk module was invoked for involving the chaotic effect of the turbulence. The numerical results were validated by experimental measurements. The results indicate that the current distribution and the bubble nucleation periodically change. Due to the slot, the bubble elimination heavily increases. The contribution of the slot to the bubble removal exceeds 50% in the case of three currents, and the promotion of the slot decays with increasing the current.

摘要：立德树人是教育的根本任务,课程思政是高校立德树人、实现“三位一体”和“三全育人”的重要举措。高职临床医学专业课程思政探索以培养医学生“爱党爱国爱人民、仁心仁术争上游”为目标,通过顶层设计、构建专业课程思政体系、培养和提升专业教师课程思政能力、积极建设课程思政资源库、改革思政教学模式、建立评价机制等路径,促进专业课程思政建设有特色、出效果、可推广。

摘要：居住建筑是城市的主体,其品质与设计方法需随时代变迁而不断更新。居住空间设计是一个多维度、跨尺度的复杂议题,在建筑学领域之外,也始终是一个不容忽视的话题。它不止于建筑学的美学与功能,更紧密联系着历史文化、社会民生、政策导向及科技发展;不止于中观尺度的建筑,还同宏观的城市与社区、微观的室内与设施等关联互动;不止于物质本体,还与人的需求感知、个体与集体的场所记忆密切相关。

摘要：石墨炔是一种同时含有sp和sp 2杂化碳的二维全炭材料,是目前为止继石墨烯之后受到关注最多的碳的同素异形体。由于其独特的电子结构,石墨炔具有很多潜在的应用和独特的性能。本文概述了石墨炔的概念及性质,综述了石墨炔的各种独特的性能及其潜在的应用,提出了合成设计的一些方案与思路,并对石墨炔研究的前景进行了展望。

摘要：二次雷达通常为固定站设计,可满足中国民航的正常空管业务需求。但对于重大活动、重大灾害和各种突发性事件,迫切需求一种能够快速安装、撤收、可用于执行机动性任务的移动式二次雷达。为此我们研制了高机动的移动二次雷达,通过创新设计,采用了标准的全尺寸天线,保证雷达的探测精度、覆盖范围均满足国际民航组织规范的要求,同时将二次雷达升级为S模式。研制成功的移动二次雷达为中国七个民航管理分局各配备了一套,七套移动式二次雷达现均投入义务运行,运行状态稳定可靠,并多次执行临时任务,为民航的雷达覆盖补盲和应急处理发挥了重要作用。

摘要：研究基于状态观测器的轮式移动机器人的路径跟踪控制问题.首先简要回顾了基于状态反馈的移动机器人的路径跟踪控制问题;进而通过适当的状态变换将移动机器人模型转换为合适的形式,并在移动机器人的位置可以测量的情况下设计了一种可保证状态观测误差指数收敛的状态观测器;最后结合状态反馈路径跟踪控制器和所设计的观测器得到了一种基于观测器的路径跟踪控制器,该控制器可以保证移动机器人的运动轨迹指数收敛到期望路径上.仿真结果证实了所提出的基于观测器的路径跟踪控制器的有效性.

摘要：基于Bragg反射光栅是一维光子晶体的一种特例结构,本文提出利用一维光子晶体带隙理论进行Bragg反射光栅设计.通过光学仿真软件OptiFDTD对Bragg反射光栅的宽度及倾斜角度误差的仿真分析,发现Bragg光栅齿刻槽宽度变化在10%范围、倾斜角度10°以内不会引起Bragg光栅衍射效率的明显变化,说明Bragg反射光栅具有较高的工艺误差容限;根据一维光子晶体带隙理论,设计了一种罗兰圆结构的Bragg衍射双光栅结构模型,实现了两个频段之间的衍射分光,优化分析结果表明:当第一套光栅中Bragg周期层数为6、第二套光栅Bragg周期层数为10时,两频段波长的衍射效率均可以达到70%左右,明显高于传统深刻蚀的衍射光栅.基于本设计的波分复用器是一种尺寸小、衍射效率高的新型EDG波分复用器,为未来高效密集型EDG波分复用器发展提供了一种新的设计思路.

摘要：Objective It is imperative to provide some consistent experimental results for the extraction of flavonid from Fructus Gardeniae. Methods The key extraction parameters that influenced the yield of flavonid from Fructus Gardeniae were optimized by employing an orthogonal experiment [L9（3）4], including the ratio of buffer solution （Na2B4O7· 10H2O） to raw material, concentration of Fructus Gardeniae in extracting solution, extraction time and pH of buffer solution. An UV/Vis detector was used to perform the qualitative and quantitative analyses of the extracted flavonid with the using of the standard sample. Results The maximum extraction yield of the crude extract was 5.0533 （mg/g） after 20 min when the mass ratio of Na2B4O7 · 10H2O to raw material was 0.4%, the concentration of Fructus Gardeniae in the extraction solution was 1/12 （g/mL）, and pH of buffer solution was 4.5. The positive reactions to the Molish and HCI-Mg tests suggested that the extracted compound was flavonoid, and FTIR measurements also identified the presence of flavonoid in the extracts. Conclusion This work is expected to provide a basis for further research, development, and utilization of Fructus gardenia in flavonid extraction.

摘要：我国直流输电线路及换流站的数量及发展速度在世界上处于领先地位,但是作为直流电网电量监测及保护的重要设备,直流电流互感器却存在许多问题,故障率很高。为此介绍一种采用饱和电抗器原理研制的SF6气体绝缘500kV直流电流互感器,设计上保证了内部直流电场强度与暂态电场强度分布合理,经过近2a的挂网试运行,各项电气性能稳定、可靠。