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溶胶—凝胶法制备薄膜湿敏元件的研究 总被引:2,自引:1,他引:1
用溶胶-凝胶法制备了R2O-Al2O3-SiO2系(R=Li,Na,K)薄膜湿敏元件,研究了它们的感湿特性,对薄膜的结构、导电机理进行了讨论,获得的湿敏元件具有响应快、滞后小和灵敏度等优点。 相似文献
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采用共沉淀法制备出SnO2-LiZnVO4系纳米粉体,考察了烧结工艺对材料微结构、湿敏特性和电容特性的影响。实验结果表明,适当的烧结工艺可明显改善纳米材料的微结构和感湿特性,采用共沉淀法制备SnO2-LiZnVO4系纳米粉体并选择好烧结温度,可使材料具有棒状晶粒微结构及低湿电阻小、灵敏度适中的湿敏试样。 相似文献
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利用等离子体辅助物理气相沉积制备化合物薄膜(氧化物、碳化物、氮化物和硫化物等)技术已广泛应用于很多工业领域,包括微电子学、光学、磁学中介质膜的沉积;切削和成形刀具上超硬碳化物和氮化物薄膜的沉积;固体润滑中硫化物薄膜的沉积,以及固体电解质薄膜的沉积等领域。事实上,等离子体物理气相沉积技术在材料制备方面已开辟了一个新的 相似文献
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《化工新型材料》2016,(9)
良好的感湿性材料应具备优良的水蒸汽透过性和相对较低的吸水性,为了获得良好的感湿性材料,设计合成含二苯基芴结构的二胺(9,9′-双[4-(2-三氟甲基-3-硝基苯氧基)苯基]芴)(BFAPH),进而与3,3′,4,4′-联苯四甲酸二酐(BPDA)、3,3′,4,4′-二苯醚四甲酸二酐(ODPA)、4,4′-(六氟异丙烯)二酞酸酐(6FDA)缩聚制得3种聚酰亚胺(PI)薄膜(PI-1,PI-2,PI-3)。对以上3种PI薄膜进行热学、力学测试,结果表明,3种PI薄膜的5%(wt,质量分数)热损失温度都在520℃以上,均具有良好的耐热性能,其中,PI-2的玻璃化转变温度最高,为288.49℃。3种薄膜的水蒸汽透过性均在6.45g/h·m2以上,尤其PI-3的水蒸汽透过性可以达到9.80g/h·m2,说明二苯基芴基团的引入提高了薄膜对水蒸汽的透过能力,并且6FDA中的三氟甲基基团存在使得PI-3薄膜疏水性大大增强。PI-3薄膜完全符合良好感湿性材料所具备的条件。 相似文献
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本工作研究了用金属丝网作骨架浸渍能透水蒸汽的高分子材料的溶液,干后形成既能透水蒸汽、又能阻挡烟尘和有害气体透过的复合材料,用这种材料作过滤器封装湿敏元件,在最佳情况下,可使其漂移值减小到仅用铜丝网过滤器时的十分之一,而对湿滞和响应时间无明显的不良影响。 相似文献
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介绍了目前露点温度传感器领域的研究现状,阐述了光学式、谐振式、电学式、热学式、重量式、化学式露点温度传感器的原理及构造,指出光学式露点温度传感器测量精度极高,其中冷镜式露点仪可作为湿度计量标准;谐振式露点温度传感器具有体积小、成本低、响应时间短、灵敏度高、可靠性好的特点;电学式露点温度传感器灵敏度高、功耗小,便于实现小型化、集成化;重量法是准确度最高的湿度绝对测量方法;化学法常用来测量低湿环境下的有机混合气体。探讨了露点温度传感器在环境监测、工业制造、医疗诊断等领域的应用情况,指出未来露点温度传感器将会向高精度、高稳定性、高响应的方向发展,且应用范围将进一步拓展,以满足极端环境下的测量需求。 相似文献
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本文以聚苯乙烯磺酸钠为湿敏材料制备了高分子电阻型湿度传感器,研究了其在高温高湿环境下,施加交流电激励后的老化行为。考察了通电电压、通电时间等对传感器响应特性的影响,并对其老化机理进行了探讨。提出通电老化后,湿敏材料在不同湿度下的电阻变化决定于高温高湿环境造成的溶解效应和施加电压后引起的通道效应和离子破坏效应。研究表明,在较高湿度环境下(87~93%RH),施加800mv的电压可加速湿敏材料的老化过程,使湿度传感器响应信号较快达到稳定,从而有望改善湿度传感器的稳定性。 相似文献
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A humidity calibrator for measurements at pressures up to 15 MPa is designed. The effect of pressure on the characteristics
of capacitive humidity sensors is demonstrated. A method of taking this effect into account is proposed. A procedure for calibrating
humidity transducers with capacitive sensors at high pressure is described.
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Translated from Izmeritel’naya Tekhnika, No. 2, pp. 61–64, February, 2008. 相似文献
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刘若望 《材料科学与工程学报》2011,(3):437-440,385
本文以聚苯乙烯磺酸钠为湿敏材料,制备了以金叉指电极为基底的高分子电阻型湿度传感器。研究了电极基片材料和叉指电极构型对传感器湿敏响应特性的影响。研究表明,采用多孔结构的基片材料可降低传感器电阻,增强湿敏膜与基片的结合能力从而提高传感器的稳定性;叉指电极构型对传感器的电阻大小有一定影响,增加电极中心线间距离使传感器的稳定性提高。 相似文献
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R. B. Salikhov A. N. Lachinov R. G. Rakhmeev R. M. Gadiev A. R. Yusupov S. N. Salazkin 《Measurement Techniques》2009,52(4):427-431
A procedure is described for formation of a nano-structured organic-organic interface with increased conductivity at the interface
of two polymer films. It is established that conductivity is determined by the type and degree of external action. It is shown
that on the basis of this interface it is possible to create chemical sensors, and in fact sensors for the relative humidity
of air, ethanol vapor pressure, and pH readings.
Translated from Izmeritel’naya Tekhnika, No. 4, pp. 62–64, April, 2009. 相似文献
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《Journal of Experimental Nanoscience》2013,8(4):302-309
Humidity sensors have multi-walled carbon nanotubes (MWNTs) as the sensing material is demonstrated. The sensor was fabricated on a silicon dioxide coated silicon wafer with metal electrodes. MWNTs were deposited and interlinked with the electrodes by means of the dielectrophoresis technique. The sensing device has the function of a hygrometer when measuring resistance variations to the local relative humidity percentage (RH%) through MWNTs. By measuring the MWNT resistances, we find that higher RH% results in a decrease of conductivity. The results indicate that electron transports in MWNTs are affected by water molecules adsorption on the outermost nanotube surface. A miniature thermocouple sensor was also fabricated and integrated with the humidity sensor. This allowed us to simultaneously sense environmental humidity and temperature. Hence, accurate humidity measurements were achieved with this prototype by calibrating the electrical resistance and temperature levels to carry out the tests with the humidity percentages. 相似文献
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M. Stankova X. Vilanova E. Llobet J. Calderer M. Vinaixa I. Grcia C. Can X. Correig 《Thin solid films》2006,500(1-2):302-308
Thin films of either pure or doped tungsten oxide were grown by radiofrequency (rf) sputtering onto silicon micromachined substrates. Up to 7 different dopant materials (noble metals or metal oxides) were deposited by rf sputtering or by evaporation onto the tungsten oxide films. The responsiveness of the resulting micromachined sensors towards sulfur dioxide and hydrogen sulfide was studied. Other pollutants in CO2 such as ethylene and methane were also tested. It was found that Au-doped tungsten oxide sensors were highly sensitive to H2S, poorly sensitive to SO2 and almost insensitive to hydrocarbons. On the other hand, Pt-doped tungsten oxide was highly sensitive to SO2, poorly responsive to H2S and nearly insensitive to hydrocarbons. By applying a principal component analysis (PCA), we show that it would be possible to selectively detect traces of H2S and SO2 in a CO2 stream using doped WO3 microsensors. These sensors could be used in a low-cost analyzer of beverage-grade CO2. 相似文献