单片集成MEMS电容式压力传感器接口电路设计

介绍了一种单片集成电容式压力传感器接口电路,该电路基于电容-频率转化原理,并通过差频消除了温度变化和工艺波动对电路性能的影响。使用Pspice对接口电路的误差特性进行了分析,并依据仿真结果确定了电路的相关参数。最后给出电路的测试结果,测试结果与仿真结果一致,在80~110kPa量程内,接口电路的分辨率为3.77Hz/hPa。     

Measurement of Slug Length and Slug Velocity in Pneumatic Conveying Using Capacitive Sensing

This paper describes a capacitive flow sensor and the development of a suitable algorithm for the determination of the slug length and the slug velocity in pneumatic dense phase conveying. The flow meter makes use of novel electrode topology. The algorithm is based on a two‐step approach using Fourier transformation. It allows for robust operation and features sub‐sample resolution for the flow parameters obtained. A process model for dense phase conveying is used to validate the proposed algorithm. Practical experiments are conducted to demonstrate the applicability of both the capacitive flow sensor and the algorithm in pneumatic dense phase conveying.     

Structural,dielectric and conductivity behaviours of cetyltrimethylammonium bromide/ethylene glycol-based quenched lyotropic mesophases

The present study highlights the effect of quenching on the structural, textural and dielectric dynamics of cetyltrimethylammonium bromide/ethylene glycol binary mixtures of varying concentrations 30:70, 50:50 and 75:25 wt.%. No mesomorphism is seen in the as-prepared binary mixtures as X-ray diffraction and polarisation optical microscopy studies reveal the crystalline-like structures for the studied concentrations. With the effect of quenching, lyotropic hexagonal phase is obtained at 30:70, 50:50 wt.% concentration; however, mixture with higher 75:25 wt.% concentrations exhibit crystalline-like phase. The obtained hexagonal lyotropic phases restrain the mesomorphism up to ≈340 K and then show crystalline-like structures with the further increase in the temperature. Dielectric and relaxation behaviours of hexagonal lyotropic phases are presented in this study. The relaxation parameters of lyotropic phases are also discussed. Interestingly, the hexagonal lyotropic phases obtained for 30:70 and 50:50 wt.% concentrations exhibit ac conductivity of the order of 10^–5 S/m, which can be seen as a significant result of this study.     

四旋翼飞行器姿态估计方法

针对四旋翼飞行器姿态估计中传感器由于旋翼振动带来的测量误差,通过卡尔曼滤波方法融合加速度计和陀螺仪的测量数据来提高姿态估计精度,减少因载体振动带来的噪声并解决陀螺漂移问题。先分析了惯性器件误差类型,然后建立了三自由度的系统模型并用Matlab进行仿真分析,再利用带有螺旋桨的实验台验证方法的可行性。实验结果表明,姿态估计误差在2°以内且没有随时间的增长而增大,基本满足四旋翼飞行器姿态估计的实时性、廉价性、高精度等要求,该方法可以成功应用于四旋翼飞行器的姿态控制,抑制噪声干扰,为稳定的自主飞行创造条件。     

Single‐Step Synthesis of Mesoporous Carbon Nitride/Molybdenum Sulfide Nanohybrids for High‐Performance Sodium‐Ion Batteries

Molybdenum disulfide (MoS₂) is a promising candidate as a high‐performing anode material for sodium‐ion batteries (SIBs) due to its large interlayer spacing. However, it suffers from continued capacity fading. This problem could be overcome by hybridizing MoS₂ with nanostructured carbon‐based materials, but it is quite challenging. Herein, we demonstrate a single‐step strategy for the preparation of MoS₂ coupled with ordered mesoporous carbon nitride using a nanotemplating approach which involves the pyrolysis of phosphomolybdic acid hydrate (PMA), dithiooxamide (DTO) and 5‐amino‐1H‐tetrazole (5‐ATTZ) together in the porous channels of 3D mesoporous silica template. The sulfidation to MoS₂, polymerization to carbon nitride (CN) and their hybridization occur simultaneously within a mesoporous silica template during a calcination process. The CN/MoS₂ hybrid prepared by this unique approach is highly pure and exhibits good crystallinity as well as delivers excellent performance for SIBs with specific capacities of 605 and 431 mAhg^?1 at current densities of 100 and 1000 mAg^?1, respectively, for SIBs.     

基于光声光谱法气体探测传声器的研究进展

光声光谱法气体探测技术具有灵敏度高、选择性高、不消耗被测量气体等优点,在现代工农业、环境监测,生物技术等领域发挥着重要的作用.随着这些领域的发展,人们对气体探测器的综合性能要求越来越高,因而光声气体探测器得到了良好的发展和应用.基于光声光谱法探测气体是利用气体光声效应原理,其中传声器是气体探测系统的一个重要声电转换器件...     

四元并行电容性Frisch栅肖特基CdZnTe探测器

由于CdZnTe(CZT)探测器尺寸和能量分辨率受到工艺限制,采用电容性Frisch栅探测器结构,将多个薄的单元探测器并行叠加使其等效为大体积的探测器,用于克服单元小探测器探测效率低的缺点,同时单极电荷的几何结果有效克服了载流子的复合.探测器的电极接触为肖特基接触( In-p/CZT-AuCl3),进一步压缩了权重势,...     

ITO Film应用于投射式电容触控面板的趋势分析

薄膜式投射电容及玻璃式投射电容是投射电容式触控面板的两种主要技术。当前随着ITO Glass的供不应求,越来越多的厂商投身于ITO Film技术的开发与应用。文章主要介绍了两种投射电容式触控技术的现况、优缺点及未来市场发展趋势。     

基于STM32的双轮平衡车

针对市场上的平衡车售价过高,功能单一,失去平衡后不能自动恢复平衡的问题,提出了基于STM32的平衡车,它采用实时操作系统uCOS-II,借助陀螺仪、加速计、舵机控制器、编码器构成一个自平衡系统。此系统可遥控控制LCD显示方向,自动恢复平衡。通过观测陀螺仪数据、功能测试、价格比较,证明此系统运行平稳,功能丰富,成本低廉。     

微型加速计全差分Σ-Δ接口IC

主要描述一种加速度感应系统全差分Σ-ΔCMOS接口IC。电容传感器接口由一个前端可配置开关电容(SC)电荷放大器和一个末端,一阶SCΣ-Δ调制器组成。本设计采用开关双采样技术(CDS)来消减低频噪声,能有效地隔离高性能Σ-Δ调制器和MEMS传感器。采用0.35μm CMOS技术,在3.3 V电源环境下能够理想工作。仿真结果显示该设计能达到0.55 V/g的精度。