摘要：This paper presents the first phase of design, analysis, and simulation for the klystron coaxial radio frequency（RF）output window. This study is motivated by 800 kW continuous wave（CW）, 650 MHz klystrons for the future plan of circular electron–positron collider（CEPC） project. The RF window which is used in the klystron output section has a function to separate the klystron from the inner vacuum side to the outside, and high RF power propagates through the window with small power dissipation. Therefore, the window is a key component for the high power klystron. However, it is vulnerable to the high thermal stress and multipacting, so this paper presents the window design and analysis for these problems. The microwave design has been performed by using the computer simulation technology（CST） microwave studio and the return loss of the window has been established to be less than-90 d B. The multipacting simulation of the window has been carried out using MultiPac and CST particles studio. Through the multipacting analysis, it is shown that with thin coating of TiN, the multipacting effect has been suppressed effectively on the ceramic surface. The thermal analysis is carried out using ANSYS code and the temperature of alumina ceramic is lower than 310 K with water *** design result successfully meets the requirement of the CEPC 650 MHz klystron. The manufacturing and high power test plan are also described in this paper.

摘要：针对现有电容器放电开环控制产生的平顶脉冲磁场稳定度难以满足核磁共振要求这一问题,提出一种平顶磁场闭环连续微调控方案。在脉冲磁体中放置一个补偿线圈,其由蓄电池供电,采用前馈控制加反馈控制的策略,利用IGBT有源区对补偿线圈的磁场进行线性调控,补偿背景磁场的波动,形成高稳定度平顶磁场。为此,设计了IGBT工作于有源区的驱动电路,搭建了原型机进行实验,结果表明,该方法能够将磁场稳定度提升至50×10^(−6),验证了方案的可行性。

摘要：USB接口具备连接简单、即插即用和热插拔等特点,用USB接口取代传统的串口和并口已经成为设计新型计算机外设的趋势.文章讨论了新型USB输入部件的设计方法,并实现了用单片机和usb接口芯片pdiusbd12设计新型空白热键和数字小键盘。

摘要：本文将聚偏氟乙烯三氟氯乙烯(PVDF-CTFE)与聚偏氟乙烯(PVDF)以2∶3共混,采用正交实验设计方法对多孔膜的制备工艺进行优化研究.结果表明,当聚合物固含量为18%(质量分数,余同),复合添加剂总含量为18%,其中丙二醇:聚乙二醇400为1∶1时,多孔膜水接触角达到93.8°,拉伸断裂强度为2.63 MPa;当壁厚为150 nm时,多孔膜超滤水通量达到183 L/(m^(2)·h),透气系数达到0.8 mL/(m^(2)·s·Pa).

摘要：本文通过扫描条形码,实现动车组重要配件出入库、调拨、退库、回收等单品管理,提升了全段的配件管理水平和管理效率。同时,系统支持配件更换、自修、委外修、报废等环节的信息采集,全面掌握重要配件的生产和流通过程,实现配件履历信息查询和状态跟踪,保障配件全面有效的实时监控,最终实现配件全生命周期管理,有效保证了配件在运用中的维修质量,确保整个铁路局的检修生产质量和行车安全。

摘要：感染新冠病毒的病人在早期的临床表现以发热为主,检测人员通常以测温为检测依据来筛查病毒感染者,但传统的测温手段对大面积人群和流动人群均不能起到很好的检测作用。基于此,文章设计双光测温智能预警系统,采用非接触式高精度红外测温仪和可见光图像采集设备,通过在硬件上的有效组合,在软件上采用图像匹配定位技术、人脸智能识别技术以及自动报警,实现远距离精确测温筛查、快速锁定高温人员的功能。