提高液体中石英晶体传感器频率稳定度的方法

石英晶体传感器的动态阻抗显著增大,品质因数下降是液体阻尼负载作用的主要效果。本文从分析液体中石英晶体谐振器的相位平衡条件出发,研究了影响传感器频率稳定度的因素;由石英晶体谐振器的能量局部化效应,分析了传感器液体测头设计中的问题,并由此设计出在液体中工作的石英晶体传感器。实验结果表明,此传感器在液体中具有较高的频率稳定度。     

基于乙酸气体传感器的海洛因快速测定方法

研究并制作了石英晶体(谐振式)乙酸气体传感器。这种传感器利用晶体表面活性酶吸附乙酸气体引起石英晶体振荡频率的变化实现对海洛因分子的快速检测。实验结果表明:乙酸激酶(aceticacidki nase简称AK)膜石英晶体传感器对乙酸气体的灵敏度为10-4;而乙酰辅酶A(acetyl-COA)合成酶膜及聚赖氨酸膜石英晶体传感器对乙酸气体的灵敏度为10-5。     

压电石英晶体传感器在单链及乙肝病毒检测中的应用

建立压电石英晶体传感器检测乙肝血液样品的方法。在石英晶体表面固定单链DNA,构建压电晶体DNA生物传感器,然后,分别与乙肝病毒的特异性片段和处理过的乙肝血液样品进行杂交反应。DNA传感器能较好地诊断出血清中的HBV病毒基因。压电石英晶体传感器操作方便、省时,且具有较好的准确度,在临床诊断中有很好的前景。     

提高液体中石英晶体传感器频率稳定度的方祛

石英晶体传感器的动态阻抗显著增大, 品质因数下降是液体阻尼负载作用的主要效 果# 本文从分析液体中石英晶体谐振器的相位平衡条件出发, 研究了影响传感器频率稳定度 的因素) 由石英晶体谐振器的能量局部化效应, 分析了传感器液体测头设计中的问题, 并由 此设计出在液体中工作的石英晶体传感器 # 实验结果表明, 此传感器在液体中具有较高的频 率稳定度.     

提高液体中石英晶体传器频率稳定度的方法

石英晶体传感器的动态阻抗显著增大，品质因数下降是液体阻尼负载作用的主要效果。本文从分析液体中石英晶体谐振器的相位平衡条件出发，研究了影响传感器频率稳定度的因素；由石英晶体谐振器的能量局部化效应，分析了传器液体测头设计中的问题，并由此设计在液体中工作的石英晶体传感器，实验结果表明，此传感器在液体中具有较高的频率稳定度。     

生物医学石英晶体传感器的研究动向

生物医学石英晶体传感器是分子生物学与微电子学、电化学等相结合的产物，本文介绍了生物医学石英晶体传感器的结构原理及研究动向。     

用于液相检测的石英晶体传感器

本文介绍了用于液相检测的石英晶体传感器的基本原理,以及基于质量、粘度、电导率变化的液相检测分析方法.还对具有很大发展潜力和重要应用价值的新型石英晶体传感器也作了简要说明.     

压电石英晶体生物传感器技术要点及展望

简介了生物传感器的分类,重点介绍了压电石英晶体生物传感器的基本原理、基本构成、检测流程、振荡电路、检测池的设计、固定化技术等内容,分析了压电石英晶体生物传感器的特点及研究中存在的不足,并对今后的研究方向提出一些看法与展望.     

压电石英晶体生物传感器应用研究进展

压电石英晶体生物传感器是利用压电石英晶体振荡频率对晶体表面质量负载和表面性状如密度、粘度、电导、介电常数等的高度敏感性与生物识别分子的高度特异性相结合发展起来的一种新型传感器。它具有灵敏度高、特异性好 ;操作简单 ,不需任何标记 ;检测速度快 ,成本低廉 ;能实时检测等特点。近年来 ,压电石英晶体生物传感器在医学实验诊断、军事监控、环境监测、食品卫生检验、工业生产实时监测等野外流动作业和在线检测等领域得到广泛应用。     

快速检测大肠杆菌O157:H7的电化学阻抗免疫生物传感器

建立了一种采用电化学阻抗谱技术快速检测大肠杆菌O157∶H7的生物传感器,它是通过石英晶体金电极表面附着一层蛋白A膜来固定抗体的。该生物传感器采用了三电极系统-工作电极石英晶体金电极、Ag/AgCl/Cl-SAT参考电极和铂对电极。和以往的普通金电极不同,第一次采用了石英晶体金电极。试验结果说明抗体的固定以及大肠杆菌O157∶H7与抗体的结合都增加了石英晶体金电极表面的电子传递阻抗,在[Fe(CN)6]3-/4-氧化还原对存在的情况下,用电化学阻抗谱测量该阻抗。该免疫生物传感器的检测限是103cfu/mL,石英晶体金电极的电子传递阻抗变化值和大肠杆菌O157∶H7的浓度在一定范围内呈线性关系,检测时间少于10 min。     

Stability study of carbon graphite covered quartz crystal

This paper shows the properties and the possibilities of carbon graphite-covered quartz crystal as an organic gas-sensing device. The carbon graphite formed on a side of quartz plate was supported by Pt electrodes. The prepared quartz crystals were heat treated for the enhancement of stability in the temperature range from 100 to 450°C. Impedance analysis of the carbon graphite-covered quartz crystal showed a larger admittance value than that of a lipid coated quartz crystal, which was based on our previous method for detecting gas components. Using the adsorption and desorption responses, the reproducibility and sensitivity are presented for describing the merits of carbon graphite-covered quartz crystal in the detection of organic gas components. The comparison of sensitivity between commercially available alcohol sensor and carbon graphite-covered quartz crystal is provided for a ppm of ethanol injection. These results prove that the carbon graphite-covered quartz crystals are usable as an organic gas sensor and as an analytical device.     

石英晶体温度传感器的应用

介绍了石英晶体温度传感器的主要性能指标。分析了石英温度传感器非线性、频率不确定度、过热效应等因素对温度测量的影响。成功地研制了采用Y +5°切的石英晶体温度传感器的温度计 ,其温度分辨力达到 10 -4 ℃。     

基于PQCR-PSL的桥梁振动无线监测系统

基于压电式石英晶体谐振器与平面螺旋电感串联结构(PQCR-PSL),结合现场可编程门阵列(FPGA)、无线传感器网络(WSNs)和C#等技术,将一种结构简单、以频率为输出的数字化石英晶体电感传感器应用到桥梁振动等低频测量中,并以此为传感器探头搭建了整套无线监测系统.系统主要由传感器探头、FPGA系统、ZigBee网络、C#位机4部分组成,具有结构简单、稳定性好、数字化输出等特点,实现了对低频振动信号的非接触式无线实时监测.     

Dew point and relative humidity measurement using a quartz resonant sensor

A new dew point measurement device for humidity measurement in high temperature environment using a quartz crystal sensor was proposed. Combined with Peltier module and quartz crystal, active condensation occurs in the quartz surface to change the mass on the surface of quartz crystal, and use the shift of its resonant frequency identify the time of condensation. This quartz sensor does not require any absorbent material, and it is directly stuck on the Peltier element. The sensor system can also be achieved relative humidity measurement based on dew point and ambient-temperature measuring. It can operate in the range of dew point temperature from 50 to ?30 °C, and in the range of relative humidity from 1 to 90 % RH. The measured dew points values and relative humidity values showed very good agreement with reference values and were within ±0.3 °C, 1 % RH, respectively over the whole temperature range.     

涂敷脲醛树脂的石英晶体微天平湿度传感器

在碱性条件下预先合成脲醛树脂单体,然后在酸性条件下于石英晶体的电极上原位合成脲醛树脂高分子薄膜,制备了石英晶体微天平湿度传感器。同时考察敏感膜厚度对检测灵敏度的影响以及传感器的响应特性、重复性和稳定性。试验结果表明:涂敷脲醛树脂薄膜的传感器频率随测试的相对湿度变化明显,传感器具有良好的重复性和稳定性。制作的湿度传感器可应用于实际的生产、生活中。     

Microscopic verification of sensitive circuits of a quartz resonator applied in dew point recognition

This paper is aimed to carry out experimental verification of sensitive circuits of a quartz resonator applied in dew point recognition and it is proven at a microscopic level to be feasible in dew point recognition with great reliability and accuracy by using the high speed video. The sensor based on the sensitive circuits of a quartz resonator is composed of a quartz crystal and a Peltier module. Proactive approach is taken to produce condensation on the surface of the quartz crystal. The electrical parameters of the quartz crystal is changed due to dew condensation and then the resonant circuit stops oscillating. Initially, it needs to analyze the oscillation circuit and electrical characteristics of the quartz crystal, and then take photos of the surface of quartz electrodes with the high speed camera and microscope. Gray statistics is made for images of dew formation in its whole process. When the statistical results are analyzed in comparison to oscillation of the circuit, it shows that the time of the circuit oscillation stopping is roughly consistent with the time when moisture condensation occurs on the surface of the quartz electrode. And the time error of the two phenomena is less than 0.5 s, which is much less than response time of the platinum resistance sensor to the temperature. Furthermore, the results provide a strong theoretical basis for further measurement of the dew point temperature by this recognition method.     

Dew point measurement for organic vapor mixture using a quartz crystal sensor

A dew point measurement device for organic vapor mixtures using a quartz crystal sensor was proposed, and its performance was examined with acetone–methanol mixtures. The device has a sensor module to accommodate the quartz crystal sensor and a cooling system. The variation in resonant frequency of the sensor indicates the condensation of sample vapor, which tells the beginning moment of condensation, i.e., dew point. The measurement results with the proposed device were compared with the predicted dew points from the UNIQUAC equation and other experimental outcome to examine the performance of the device. Though some measurement error was yielded, it is proved that the proposed device is useful for measuring the dew points of organic vapors at different pressures.     

液体介质石英晶体谐振传感器

报导一种可以在液体介质中稳定振荡的石英晶体传感器，介绍其原理，探头结构以及振荡电路，并给出有关实验结果。     

High-precision low-power quartz tuning fork temperature sensor with optimized resonance excitation

This paper presents the design, fabrication, and characterization of a quartz tuning fork temperature sensor based on a new ZY-cut quartz crystal bulk acoustic wave resonator vibrating in a flexural mode. Design and performance analysis of the quartz tuning fork temperature sensor were conducted and the thermal sensing characteristics were examined by measuring the resonance frequency shift of this sensor caused by an external temperature. Finite element method is used to analyze the vibratory modes and optimize the structure of the sensor. The sensor prototype was successfully fabricated and calibrated in operation from 0 to 100 °C with the thermo-sensitivity of 70×10^?6/°C. Experimental results show that the sensor has high thermo-sensitivity, good stability, and good reproducibility. This work presents a high-precision low-power temperature sensor using the comprehensive thermal characterization of the ZY-cut quartz tuning fork resonator.