硬粒子对聚合物材料表面的冲击摩擦研究

冲击摩擦为接触面切向与法向冲量之比。用聚合物材料试件与弹簧钢片组成振动测试系统 ,硬粒子以一定入射角冲击试件水平面引起系统振动 ,接触冲量通过振幅反映出来 ,记录初始振幅值而计算出一个冲击过程的冲击摩擦因数。结果表明 ,当入射角α在 2 5°-60°变化时 ,冲击摩擦因数f从 0 .5降至 0 .2左右。文章同时分析讨论了摩擦对聚合物表面接触强度的影响。     

基于FLO-2D的泥石流工程治理效果分析——以都江堰银洞子沟泥石流为例

选取地震区典型泥石流沟银洞子沟作为研究对象,运用FLO-2D软件再现该沟2013年泥石流发生过程,验证了通过研究区雨量数据获取泥石流流量线方法的可靠性以及相关模拟参数选取的合理性。在此基础上,基于泥石流发生频率和暴雨爆发频率相同的假设,对不同爆发频率下的泥石流工程治理效果进行了分析。结果表明:工程治理后,当爆发频率为30,50 a时,工程治理效果显著;当爆发频率为100 a时,工程治理效果不显著。因此,建议相关管理部门加强极端降雨条件下泥石流的预警和防治工作。     

Aqueous and nonaqueous microemulsion systems with a palm oil-base emollient

Microemulsions with a palm oil-based emollient, i.e., medium-chain triglyceride (MCT), and water or glycerol, stabilized by two oppositely charged ionic surfactants and a medium-chain alcohol, were investigated. The results showed that only the water-in-MCT or the glycerol-in-MCT microemulsions were prominent. The maximum solubilization of the MCT emollient was higher in cetyltrimethyl ammonium bromide, i.e., the positively charged surfactant that contained a nitrogen atom, than the negatively charged surfactant sodium dodecyl sulfate. However, the results did not lend themselves for selecting any decisive factor that would explain the different solubilization behavior encountered in the investigated aqueous and nonaqueous systems.     

水轮发电机转子系统磁悬浮装置 结构优化设计

针对水轮发电机混合磁悬浮承重系统中电磁悬浮装置局部磁饱和问题,进行了结构优化设计,提出了适当增加推力盘及电磁铁顶部厚度的方法,有效地减轻了电磁悬浮装置局部磁饱和现象,同时也使总的磁浮力有所增加。从承载力与漏磁角度考虑,得出了推力盘及电磁铁顶部厚度的最佳设计值。     

基于晶闸管的直流可控避雷器关键技术

电网换相换流器(LCC)与模块化多电平换流器(MMC)级联系统具备诸多独特优势,但其低压端模块化多电平换流器(MMC)由多个电压源换流器(VSC)换流器并联组成,当发生交流侧故障时会引起低压端直流母线过电压。为抑制MMC过电压问题,提出在直流母线侧安装直流可控避雷器。对交流侧故障时MMC过电压机理进行了理论分析,提出了直流可控避雷器拓扑结构。在深入分析直流可控避雷器不同运行方式的基础上,给出了直流可控避雷器的直流混合可控开关所需的极限电流耐受能力。为实现开关触发的快速性,提出在直流混合可控开关中采用串联晶闸管阀组方案。通过晶闸管Cauer计算模型仿真研究了极限电流下晶闸管阀组瞬态结温,验证了设计方案的合理性。基于某规划直流工程进行直流可控避雷器设计,并给出了主设备布置方案。基于PSCAD/EMTDC平台搭建了系统的仿真模型,验证了所提出的直流可控避雷器拓扑抑制系统MMC过电压的有效性。     

Advanced Nanostructured Anode Materials for Sodium‐Ion Batteries

Sodium–ion batteries (NIBs), due to the advantages of low cost and relatively high safety, have attracted widespread attention all over the world, making them a promising candidate for large‐scale energy storage systems. However, the inherent lower energy density to lithium–ion batteries is the issue that should be further investigated and optimized. Toward the grid‐level energy storage applications, designing and discovering appropriate anode materials for NIBs are of great concern. Although many efforts on the improvements and innovations are achieved, several challenges still limit the current requirements of the large‐scale application, including low energy/power densities, moderate cycle performance, and the low initial Coulombic efficiency. Advanced nanostructured strategies for anode materials can significantly improve ion or electron transport kinetic performance enhancing the electrochemical properties of battery systems. Herein, this Review intends to provide a comprehensive summary on the progress of nanostructured anode materials for NIBs, where representative examples and corresponding storage mechanisms are discussed. Meanwhile, the potential directions to obtain high‐performance anode materials of NIBs are also proposed, which provide references for the further development of advanced anode materials for NIBs.     

城市轨交自动售检票车站管理系统的研究与实践

城市轨道交通自动售检票车站管理系统在轨道交通运营中直接面向乘客,并在线路自动售检票系统中承担着承上启下的关键作用。从车站管理系统的功能需求出发,结合自动售检票系统具有分层系统的结构特征,对车站管理系统的构架模式和参考模型进行研究和设计,提出关于XML规范接口协议简约与重构的技术思路,描述异构平台数据收发的处理流程,并给出基于WPF技术编程实现设备运营监控界面示例。     

Preparation,swelling properties,and displacement performance of functional amphiphilic microspheres

Because polymers containing benzyl chloromethyl groups are easily modified for functional production, the dispersion polymerization of acrylamide, 4‐vinylbenzyl chloride, and N,N‐methylene bisacrylamide in dimethylformamide initiated with α,α‐azobisisobutyronitrile was carried out to produce amphiphilic microspheres containing benzyl chloromethyl groups. The structure of the amphiphilic microspheres was determined by IR and ¹H‐NMR spectroscopy. The polymerization conditions, the temperature, amount of crosslinking agent, and initiator included, were optimized. The size distribution of the microspheres after swelling equilibrium ranged from 4 to 62 μm. The swelling behavior of the microspheres was also investigated. The increase in temperature and the decrease in salinity caused a gradual increase in the swelling ratio. The prepared microspheres were transported uniformly in porous media when the permeability was 0.436 μm². The oil displacement experiments indicated that amphiphilic microspheres had the ability to enhance oil recovery under homogeneous and heterogeneous conditions but was more suitable for heterogeneous formation. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41578.     

小套管井无油管采油技术的研究与应用

近年来,内径小于?101.6 mm的小套管井在临盘采油厂渐成规模,已成为原油生产的重要组成部分。但由于套管内径限制,该类油井泵径小、杆管间隙小,导致提液困难和杆管偏磨。本研究提出了小套管井无油管举升的技术理念,配套完成了小套管井无油管杆式泵锚定技术、空心杆注塑防偏磨技术、无油管采油井口出油系统及举升工具的设计与室内试验,形成了一套完整的小套管井无油管举升实用技术。现场试验表明,该技术满足了小套管井现场提液、防偏磨的需要,有效降低了生产成本,是一种技术可靠、使用简单、成本低廉的技术手段,对油田小套管井的高效开发具有重要意义。     

依赖多子群分层混合算法的云计算信息系统安全等级保护测评

基于多子群分层混合算法的云计算信息系统的概念和信息安全等级保护(Information security level protection,ISLP)的基本内涵,研究了云计算信息系统的系统结构和信息处理机制。其中,提出了一种多子群分层混合算法的云计算信息系统信息安全等级保护测评方法,即分布式配置与集中式云计算相结合,及其软硬件框架与感知检测集成,并提出了基于镜头原理的信息处理框架及其接收信息处理的流程。设计了多子群分层混合算法,利用镜头聚焦模型和五个阶段的信息处理序列,建立并解析了云计算的工作规律及其自反馈调整,验证了所提出思想的合理性和优势。