液压碳石墨密封环激光辅助车削的加工性能研究

为了实现液压碳石墨密封环的高效车削加工,采用激光辅助加工方法,进行了碳石墨密封环材料的激光辅助车削加工研究.考虑到碳石墨密封环材料具有高强度、高硬度等特点,利用激光束对工件进行局部加热,以提高加工效率、减小切削力和刀具磨损.针对碳石墨M104密封环的车削加工过程,进行了常规切削和激光辅助切削的对比实验研究.设计了激光辅助加工的实验流程,并进行了工艺参量的合理选择,得到了较高的切削效率.结果表明,激光辅助切削的主切削力和径向力分别比常规切削下降了23.5%和19.9%;激光辅助切削的切削区温度分布与常规切削相近;刀具磨损和破损的程度较小,能获得较好的表面加工质量.     

20万t/a硫磺回收装置运行优化

针对普光气田高含硫净化装置20万t/a硫磺回收装置的运行情况,对不足之处进行优化。通过增加热启动程序,解决了装置恢复生产及运行工作中的克劳斯炉长明灯积硫、硫封堵塞、尾气SO2排放量较高等一系列复杂的难题,节约了大量开工及运行成本,实现了装置恢复生产及运行期间零事故率及环保生产的目标。     

利用寻线传感器的物流车设计

以制造装配类企业的车间物流、大型仓储物流和港口码头物流方式的柔性化为基础,基于物流车的智能化控制要求,对小型车间引导物流车进行研究和设计,介绍物流车的总体结构、运动过程及控制系统。该物流车以Arduino MEGA1280为主控制器,在车间环境中能按指定轨道寻线行走,实现车辆的行走、物件抓放、升降、旋转和伸缩等功能,可自动搬运工件,定位准确,操作灵敏,从而提高了车间物流方式的智能化、柔性化,有利于提高劳动生产率。     

L-Phe印迹P(AN-co-AA)纤维的制备与性能研究

以丙烯腈聚合物为载体,以印迹分子L-Phe纤维为研究对象,采用气流静电纺丝方法制备出具有L-Phe印迹性能的P(AN-co-AA)超细纤维,通过对该纤维在不同pH值溶液中的印迹性能研究,得到了最佳制备工艺参数,成功制备出了L-Phe印迹纤维。     

智能封堵器水上通信中单片机系统电路的设计

为了实现封堵器海洋工作环境中的无线遥控动作,封堵器在海底工作中采用了水声通信技术.文章首先介绍了水声通信系统的整体设计.在前期工作中,从影响水声通信的因素出发,对水声通讯频率的选择及水声换能器的选型进行了研究,确定了水声通讯的载波频率.在此基础上提出了基于单片机的水声Modem的制作方案,设计了单片机系统电路.并对单片...     

真空碳酸盐法焦炉煤气脱硫工艺优化

根据焦化厂脱硫现状,对脱硫系统及相关工序的工艺流程进行优化,对相关设备进行改造,使脱硫工序的开工率大幅度提高,硫产量得到大幅度提升。     

A RF receiver frontend for SC-UWB in a 0.18-μm CMOS process

正A radio frequency(RF) receiver frontend for single-carrier ultra-wideband(SC-UWB) is presented. The front end employs direct-conversion architecture,and consists of a differential low noise amplifier(LNA),a quadrature mixer,and two intermediate frequency(IF) amplifiers.The proposed LNA employs source inductively degenerated topology.First,the expression of input impedance matching bandwidth in terms of gate-source capacitance, resonant frequency and target S_(11) is given.Then,a noise figure optimization strategy under gain and power constraints is proposed,with consideration of the integrated gate inductor,the bond-wire inductance,and its variation.The LNA utilizes two stages with different resonant frequencies to acquire flat gain over the 7.1-8.1 GHz frequency band,and has two gain modes to obtain a higher receiver dynamic range.The mixer uses a double balanced Gilbert structure.The front end is fabricated in a TSMC 0.18-/im RF CMOS process and occupies an area of 1.43 mm~2.In high and low gain modes,the measured maximum conversion gain are 42 dB and 22 dB,input 1 dB compression points are -40 dBm and -20 dBm,and S_(11) is better than -18 dB and -14.5 dB.The 3 dB IF bandwidth is more than 500 MHz.The double sideband noise figure is 4.7 dB in high gain mode.The total power consumption is 65 mW from a 1.8 V supply.     

A multi-mode multi-band RF receiver front-end for a TD-SCDMA/LTE/LTE-advanced in 0.18-μm CMOS process

正A fully integrated multi-mode multi-band directed-conversion radio frequency(RF) receiver front-end for a TD-SCDMA/LTE/LTE-advanced is presented.The front-end employs direct-conversion design,and consists of two differential tunable low noise amplifiers(LNA),a quadrature mixer,and two intermediate frequency(IF) amplifiers.The two independent tunable LNAs are used to cover all the four frequency bands,achieving sufficient low noise and high gain performance with low power consumption.Switched capacitor arrays perform a resonant frequency point calibration for the LNAs.The two LNAs are combined at the driver stage of the mixer,which employs a folded double balanced Gilbert structure,and utilizes PMOS transistors as local oscillator(LO) switches to reduce flicker noise.The front-end has three gain modes to obtain a higher dynamic range.Frequency band selection and mode of configuration is realized by an on-chip serial peripheral interface(SPI) module.The frontend is fabricated in a TSMC 0.18-μm RF CMOS process and occupies an area of 1.3 mm~2.The measured doublesideband (DSB) noise figure is below 3.5 dB and the conversion gain is over 43 dB at all of the frequency bands. The total current consumption is 31 mA from a 1.8-V supply.     

节材节能的模锻工艺——小飞边模锻

一般的闭式锻造要求下料精度很高,限制了它的应用范围。为了克服上述缺陷,作者通过选用合适的毛坯尺寸、设计了混合型飞边槽、又针对环类锻件设计,带有自动开启的飞边槽的结来实现小飞边模锻。小飞边模锻节材20％以上,模具寿命几乎提高一倍。     

食品中杏仁过敏原成分的检测

目的：建立检测食品中桃仁、杏仁过敏原成分的荧光PCR 方法,比较国外3 种ELISA 试剂盒效果。方法：针对杏仁Pru du1 基因设计引物及探针,建立荧光PCR 方法。利用杏仁过敏原参考物质对3 个品牌的ELISA试剂盒的回收率进行比较。结果：建立的荧光PCR 方法,具有很好的特异性;灵敏度为10mg/kg。结论：桃仁及杏仁过敏原成分荧光PCR 检测方法特异性好、灵敏度高,对食品中过敏原的检测有重要的实际意义。