共查询到17条相似文献,搜索用时 237 毫秒
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限于传统涂敷敏感膜的声表面波(SAW)气敏传感器存在成膜困难和选择性差、重复性差以及再生性差等问题,本研究提出一种基于压电基底表面气体气液相转换效应机理的瑞利波传感器。在此基础上开发了一种基于瑞利声表面波传感器和气相色谱(GC)分离柱的便携式气体检测系统。最后实验论证了方案的可行性,初步的实验结果表明该系统具有分析时间短、选择性好、灵敏度高,可检测ppb(10^-9)浓度的混合VOCs以及成本低等优势,显示其在痕量挥发性有机气体检测和分析应用上有良好的潜力和前景。 相似文献
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声表面波(SAW)传感器阵列具有体积小、功耗低、反应灵敏等优点,在食品检测、环境治理、气体鉴别等领域有广泛的应用前景。结合声表面波传感器阵列的原理及特点,建立和优化了声表面波传感器阵列的数学模型,并对数据进行预处理、主成分分析(PCA)以及BP神经网络分析处理,实现了对气体的鉴别分类,取得了好的实验结果。 相似文献
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气敏材料是气体(化学)传感器的核心部位,直接影响传感器的稳定性、选择性、灵敏度和响应时间等各种性能。卟啉与金属卟啉配合物具有优良的气敏性能,目前国内外卟啉与金属卟啉传感器已应用于VOCs的检测。该文介绍了卟啉及其结构、合成方法、卟啉和金属卟啉配合物的合成及影响因素;卟啉和金属卟啉在传感器中的应用和对挥发性有机气体的检测原理。 相似文献
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I. SayagoAuthor Vitae M.J. FernándezAuthor VitaeJ.L. FontechaAuthor Vitae M.C. HorrilloAuthor VitaeC. VeraAuthor Vitae I. ObietaAuthor VitaeI. BusteroAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(1):1-5
Surface acoustic wave (SAW) gas sensors based on polyisobutylene (PIB) and composites (PIB and carbon nanotubes) as sensitive layers were investigated for the detection of octane and toluene (volatile organic compounds) and other atmospheric pollutants (H2, CO, NO2 and NH3) at room temperature. In order to study the effect of nanotubes in the response of SAW sensors, several composites based on PIB with different percentages of multiwalled carbon nanotubes (MWNTs) were tested and compared to the response obtained from PIB SAW sensors. Sensors exhibit high responses and selectivity to volatile organic compounds (VOCs) with fast response and recovery times as well as good repeatability and reproducibility. Experimental results show as small percentages of nanotubes improve the response to octane. 相似文献
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为实现高灵敏度、低温漂的高性能电流传感器,提出将声表面波技术与磁致伸缩效应相结合的电流检测方法,分析了其敏感机理并改善其温度特性.这种声表面波电流传感器采用128°YX-LiNbO3作为压电基片,表面覆盖SiO2薄膜来改善器件温度稳定性,并溅射超磁致伸缩TbDyFe薄膜以响应电流.在电流作用下,TbDyFe薄膜会发生磁致伸缩效应和ΔE效应,引起声表面波相速度的改变.结合层状介质中声传播理论,分析了给定电流下层状结构中声表面波的传播特性,特别分析了TbDyFe和SiO2膜厚对传感器响应的影响.计算结果表明,TbDyFe和SiO2薄膜厚度分别为0.5μm、2μm时,该声表面波电流传感器具有最大检测灵敏度58.2 kHz/A,有良好温度稳定性和较高的灵敏度,从而为高性能声表面波电流传感器的研制奠定理论基础. 相似文献
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基于声表面波(SAW)技术的化学毒剂传感器在检测下限、响应速度以及减小温度、湿度交叉敏感等方面还需进一步提高。提出了在SAW双端口谐振器上涂敷超支化聚合物的方法提高传感器的检测下限和灵敏度。通过建立Van Dyke模型,分析了敏感膜对SAW化学毒剂传感器Q值、插入损耗以及电路阻抗匹配的影响。利用谐振器代替延迟线,确保了器件具有插入损耗、高Q值的特点。实验证实,在谐振器的中心栅结构上涂覆聚合物可以减小粘弹性聚合物对谐振器插损、Q值以及输入输出阻抗的影响。对设计的化学毒剂传感器进行了沙林毒剂检测实验,采用315MHz的SAW谐振器结合超支化聚合物膜,检测沙林气体浓度为5.0mg/m^3。实验表明:这种传感器的灵敏度可达到600Hz/mg/m^3,响应时间为50s,恢复时间约为60s。 相似文献
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The power consumption of a surface acoustic wave (SAW) sensor system was investigated using ANSYS and PSPICE. Simulation results show that several design parameters of the surface acoustic wave sensor, such as the center distance between two interdigital transducers (IDT), the thickness of the piezoelectric substrate, the finger space of the IDT, etc., can greatly affect the power consumption of the whole system. The results of this study will be helpful to optimum design and fabricate the SAW sensor systems with very low-power consumption. 相似文献
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A surface acoustic wave (SAW) piezoelectric device with a dual-path SAW delay line oscillator configuration has been developed to detect nitrogen dioxide (NO2) gas. One delay line is coated with a Langmuir-Blodgett (LB) film of copper tetrasulphonated phthalocyanine (CuTsPc), while the other is uncoated. NO2 gas can be selectively abosorbed by the CuTsPc LB film and then alters the SAW characteristics, which in turn causes the oscillation frequency to change. The concentration of NO2 can be detected by measuring the relative change in the frequency of the two oscillators. The CuTsPc LB film-coated SAW device has been demonstrated to be sensitive to low concentrations of NO2 gas. There is a linear relationship between NO2 concentration and frequency change under 12 ppm NO2 concentration. The sensitivity of the device is about 128 Hz/ppm NO2. The response time is 10 min, and the recovery is 40 min. It can be applied as a small, inexpensive and sensitive NO2 gas sensor. 相似文献