一种新型悬臂棒条筛的设计与应用

介绍了一种新型悬臂棒条筛分机械,论述了其结构、工作原理和技术特性。从理论和实践两方面论证了它的结构、处理能力、筛分效率、返矿率都明显优于普通悬臂棒条筛分机械,可广泛应用于高炉槽下烧结矿的筛分作业。     

减震垫铁在普通车床上的使用效果分析

机床安装时采用减震垫铁代替普通垫铁具有方便、迅速，减震、隔振等优点，但应用于普通车床时存在着明显的振动。通过在CA6140车床上的激振对比试验及车削试验，发现在130Hz附近，车床导轨水平方向的振幅明显加大。从而得出结沦：普通车床床身的刚性对减震垫铁的使用有一定的影响。     

基于震动信号HHT的车辆分类

震动传感器是智能监控传感器系统的重要组成部分。震动信号是一种非线性非平稳信号。相比于传统的时频分析方法,对希尔伯特-黄变换是一种更有效地处理非平稳信号的时频分析方法。将希尔伯特-黄变换引入到车辆分类中,提取震动信号特征信息,利用经验模态分解(EMD)获得车辆行驶引起的地面震动信号的固有模态函数(IMF),通过选取的固有模态函数得到相应的希尔伯特谱,然后在希尔伯特谱的基础上根据谱峰对车辆进行分类。仿真测试结果表明方法具有很高的正确率。     

振弦式力传感器一带二接线技术试验研究

大坝安全监测所用的振弦式测力监测仪器一般采用四芯屏蔽电缆实现信号输入和输出。”一带二”技术是在实际工作中根据施工现场的需要总结出来的一种应急补救措施。当振弦式仪器的信号电缆在埋设施工后,发生电缆故障时可以采取该技术措施来进行补救处理。试验结果表明监测信号完整且相互之间无干扰。     

A resonating rheometer using two polymer membranes for measuring liquid viscosity and mass density

A resonating sensor for mechanical liquid properties facilitating measurements at two different modes of operation is presented. One mode is more sensitive to liquid viscosity the other to mass density. A sample liquid is subjected to time-harmonic shear stress induced by two opposed vibrating polymer membranes. These membranes, placed in an external static magnetic field, carry two conductive paths each. The first path is used to actuate the membranes by means of Lorentz forces while the second acts as a pick-up coil providing an induced voltage representing the movement of the membrane. From the resulting frequency response the liquid's viscosity and mass density can be deduced. This double membrane based setup allows examining the test liquid at adjustable frequencies in the low kilohertz range from 500 Hz to 20 kHz by varying the gap between both membranes. The sensor is suitable, e.g., for low cost handheld devices with inline capabilities and disposable sensor elements for measuring Newtonian liquids such as, e.g., oils and aqueous solutions.     

一种高精度气压式高度表的设计

采用振动筒式压力传感器,结合单片机技术设计了一种高精度的数字式气压高度表,文中详细的论述了硬件设计,给出了软件设计流程,并从硬件上和软件两方面对引起测量压力的温度误差、静压误差和非线性误差进行了补偿,进一步提高了气压高度表的实际精度,该气压高度表与传统膜盒式气压高度表相比,具有精度高、结构简单、体积小和重量轻等优点。     

带有摩擦阻尼振动给料机的动力学仿真分析

本文介绍了带有摩擦阻尼的振动给料机的结构特点，建立了振动给料机在既有粘性阻尼又有摩擦阻尼的情况下受简谐激励振动时的力学模型。通过将运动微分方程中的理想干摩擦阻尼力展开为Fourier级数，取级数展开的第一项作为近似，求出了振幅及相位差角的一般表达式。最后应用Matlab语言实现了振幅、相位的参数计算，绘制出不同粘性阻尼和摩擦阻尼时幅频特性曲线和相频特性曲线。并与之结合，分析讨论了理想干摩擦阻尼对幅频特性和相频特性的影响，指出了摩擦阻尼与粘性阻尼结合可以有效降低共振时的振幅，且共振时，若摩擦力按线性增加则振幅按线性衰减；而粘性阻尼较小时．理想干摩擦阻尼力对相频特性的影响极为明显。     

Dielectric behavior and magnetical response for porous BFO thin films with various thicknesses over Pt/Ti/SiO2/Si substrate

A novel sol–gel method has been developed to deposit multiferroic nanocrystalline bismuth ferrite (BFO) thin films over Pt/Ti/SiO₂/Si substrate by spin-coating technique with various thicknesses. It is found that the deposition parameters significantly influence the quality and the thickness of BiFeO₃ films. The films are all uniform and adherent to Pt/Ti/SiO₂/Si substrate. The spin-coated films are characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Atomic force microscope (AFM), photoluminescence spectroscopy (PL) and Fourier transform infrared spectroscopy (FTIR). Rhombohedral structure of BFO is confirmed from the XRD and FT-IR studies. The SEM image shows a porous structure formation of BFO over Pt/Ti/SiO₂/Si substrate. The surface outgrowth for the films at various thicknesses is measured from root mean square (RMS) and surface roughness through AFM. The step height and the RMS are found to be high for the film at 500 nm in comparison with thickness of 200 nm. The influence of the dielectric properties of the porous BFO at different thicknesses is studied using LCRQ meter. Finally, the magnetic behavior of film is compared with M–H hysteresis loop and Magnetoresistance (MR) studies.     

沙曲选煤厂技术改造方案探讨

针对沙曲选煤厂、旧系统存在问题,对选煤工艺改造方案进行探讨,即采用预脱泥有压两产品重介旋流器主再洗、毛煤动筛排矸、浮选精煤加压过滤机回收、尾煤压滤回收工艺.通过试运行,设备状况良好,基本达到设计生产能力.     

振动放矿设备结构优化设计探讨

国内生产厂家所生产的振动放矿机适于其后续设备为汽车、矿车等断续设备，对于矿石性质变化大又要求恒定给矿的带式输送机如何均匀放矿，国内尚无应用。本文从优化振动放矿机几何结构、增设变频器、设置反扇形闸门等措施，使给矿均匀、矿流平稳，并对矿石性质的变化适应性强，防止和减少了溜井跑矿的危害。