基于固体电解质的CH_4电化学传感器评述

基于固体电解质的电化学传感器可以在高温条件下实时、原位地检测气体组成。固体电解质和电极材质的不同会直接影响传感器的灵敏度、选择性以及响应时间。根据测量原理的不同,固体电解质基CH4电化学传感器通常分为电流型CH4传感器和电势型CH4传感器,对这两类传感器进行了详细的介绍,并对固体电解质基CH4电化学传感器在海底火山、热液喷口区等高温高压极端环境的研究与应用进行了展望。     

固体电解质电位型甲烷传感器的气敏性能研究

研究了甲烷浓度和工作温度对氧化锆基混合电位型传感器响应值的影响.以氧化钇稳定的氧化锆(YSZ)为固体电解质,氧化锡(SnO2)为工作电极的传感器对(200~1000)×10 -6浓度的甲烷具有良好的传感性能,传感器响应值与甲烷浓度的对数值呈良好的线性关系,传感器在650℃时具有良好的传感性能,其中响应时间和恢复时间均低至5 s.     

固体电解质氧传感器的发展趋势

固体电解质氧传感器在国防科研领域有着广泛应用,尤其在精密的航天仪器中,固体电解质氧传感器扮演着不可替换的角色.介绍了固体电解质氧传感器的工作机理与分类,结合国内外研究现状总结了固体电解质氧传感器的发展趋势,对氧传感器数值仿真与实验相结合的研究方法提供了参考,并对固体电解质氧传感器在国防科研领域的应用前景进行了概述.     

混合位型NOx传感器的研究与进展

混合位型NOx传感器是新近发展起来的一种NOx传感器。主要介绍了混合位型NOx传感器的研究情况及固体电解质材料（ZrO2）的工作机理。简要分析了传感器研究的发展方向。     

固体电解质化学传感器的进展

<正> 固体电解质电化学传感器是化学传感器的一个重要门类。随着各种固体电解质材料的不断研制和改性提高,固体电解质传感器品种正在日益增多,应用领域也在不断扩大,其研制开发十分活跃并取得许     

发明与专利

一种采用复合固体电解质膜的CO传感器 【摘要】CO传感器包括：气体过滤器、CO进气隔板、上气体扩散层、绝缘密封圈、密封胶圈、电解质膜组件、下气体扩散层、空气进气隔板和传感器壳体;电解质膜组件是质子交换膜燃料电池用的复合固体电解质膜电极组件,膜电极组件由复合固体电解质膜和催化剂层构成,     

基于YSZ的混合电动势型NO2传感器的研究进展

YSZ作为一种固体电解质,因其优异的离子导电率和热稳定性而被广泛应用到气体传感器中.该文简要介绍了YSZ的结构、特性以及基于YSZ的混合电动势型NO2传感器的研究进展,讨论了影响传感器性能的主要因素,分别从三相界面、敏感材料的种类以及敏感材料的形貌3方面进行综述.增大三相界面面积、合成新型敏感材料、改变敏感材料的微观结...     

极限电流型氧传感器的研究

极限电流型氧传感器工作原理是基于稳定ZrO2固体电解质的氧泵作用,通过气体扩散控制供给阴极的氧而得到极限电流。基于该原理,研制了用ZrO2固体电解质和多孔陶瓷基片作为扩散层构成的多孔层型氧传感器。在N2-O2混合气体中,对传感器的性能进行测试,结果表明:传感器的测量范围为0~10%氧摩尔分数时,灵敏度为0.5mA/10-2,工作温度为650~800℃,线性度为±5%。     

新型电化学传感器的研究进展

在电化学传感器的发展过程中,曾经出现过水液体电解质电化学传感器、有机溶剂电解质电化学传感器和离子液体电解质电化学传感器等类型。其中,水液体电解质电化学传感器的电解液易蒸发,传感器的寿命较短;有机溶剂电解质电化学传感器的电解质易燃,反应体系复杂;离子液体电解质电化学传感器容易出现漏液、腐蚀电极等问题。为了彻底解决以上问题,人们将研究的重点放在了固体电解质的开发,并取得了较大的进展。     

平面型内加热式固体电解质 CO2传感器的静态特性

利用固体电解质材料制成的CO_2传感器响应速度快、对水汽和其他气体干扰的抗力强,应用前景乐观.但这种传感器都属外热形式,以致体大、价高、功耗大,不利使用,需要改进.为此,本实验把它改成为:将加热用的铂丝置入元件体内,经压制成平板型结构.这样,不但消除了上述所说的不足处,而且获得了基本不受共存氧的影响.     

卟啉传感器检测挥发性有机化合物的研究进展

卟啉与金属卟啉具有优良的气敏性能,是检测挥发性有机化合物(VOCs)的理想敏感材料。卟啉与金属卟啉传感器已成功地应用于VOCs的检测。基于不同类型传感器的传感原理,对目前国内外用于VOCs检测的几类卟啉传感器的研究进展进行了分类介绍,并对卟啉传感器在VOCs检测领域的研究方向和发展前景做了展望。     

Environmental gas sensing

Solid-electrolyte sensors for detecting air pollutants are urgently needed for the sake of environmental protection. Rapid progress is being marked in the development of sensors for CO₂, NO₂, NO, SO₂, ozone and fluorocarbons. Some of them, such as the CO₂ sensor, have almost reached a stage of practical application, while others are very promising. Most of these sensors have been fabricated with ceramic materials that are solid electrolytes and oxide semiconductors. The current status of research and development for air-pollutant sensing is described briefly.     

Optimization of single mode fibre sensors to detect organic vapours

The construction of single mode optical fibre (SMF) sensors to handle with volatile organic compounds (VOCs), has been optimized to operate at the third telecommunication window (1550 nm). The main motivation is to take advantage of the photonic devices used in telecommunication systems that makes easier sensors multiplexing. Moreover, the low transmission attenuation at that wavelength offers the possibility of remote sensing. The sensing materials used suffer reversible structural alterations in the presence of VOC, such as colour change, which are detectable with a photonic system. Following the Electrostatic Self Assembly method (ESAm), a nanostructure is constructed onto cleaved ended SMF, which is doped with a sensing material. The fabrication of this type of sensors was focused on multimode fibres (MMF) and in the visible spectral range (VIS) so far. The implementation has been adapted to SMF and to operate around 1550 nm, specifically, by easing the adsorption of the VOCs molecules. It has been observed that the sensing material affects the morphology of the nanostructures as well and so, to the sensors response. The devices implemented show a potential use in the identification of single and complex mixtures of VOCs.     

Effect of trace residual ionic impurities on the response of chemiresistor sensors with dithiol-linked monolayer-protected gold (nano)clusters as sensing interfaces

Column liquid–solid chromatography was used to remove residual impurities of isolated n-octanethiol (C₈H₁₇SH) monolayer-protected gold nano-clusters (MPCs) which were synthesized by a Brust two-phase method. Three-dimensional (3D) cross-linked MPC films were prepared directly on interdigitated electrodes to form chemiresistor sensors through the exchange reactions of the chromatographically purified MPCs with 1,6-hexanedithiol (HDT) or 1,4-benzenedimethanethiol (BDT). Ionic current induced by trace residual ionic impurities in MPCs was qualitatively detected by comparing the resistance responses of the sensors interfaced with the chromatographically purified and unpurified MPC films by employing volatile organic compounds (VOCs) and water vapor as probes, respectively. The existence of the ionic current significantly decreases the sensor sensitivities to VOCs. As for water vapor with high permittivity, the ionic current totally distorted the resistance responses from positive to negative with increasing humidity. Capacitance was also measured to characterize the permittivity change. The effect of ionic current on capacitance was not obvious. The humidity effects on the sensor responses to VOCs were also investigated. Fewer effects were observed on the higher hydrophobic compounds. A ternary sensor array was constructed with C₈Au MPCs, HDT and BDT cross-linked MPC films as sensing interfaces. The response pattern showed that the sensor array could discriminate VOCs with different functional groups. The as-prepared sensor showed the same sensitivities as the acoustic wave sensors.     

Monitoring of melanoma released volatile compounds by a gas sensors array: From in vitro to in vivo experiments

The analysis of the volatile organic compounds (VOCs) released by bio-systems represents a promising approach for the diagnosis of human diseases including cancers. Experimental results suggested the possibility to detect tumors in vivo through the analysis of released VOCs from different body compartments, such as breath and skin. This paper illustrates the results obtained measuring VOCs mixtures released by well-characterized tumor cells derived from human malignancies by using an array of broadly selective chemical sensors. The patterns of VOCs emitted by two different melanoma tumorigenic cell lines transplanted ad hoc in a mice model were investigated. The recorded sensors signals are compatible with the existence of a distinguishable tumor specific pattern of VOCs evolving during the exponential phase of tumor growth.     

Optical VOCs detection using poly(3-alkylthiophenes) with different side-chain lengths

The use of conjugated polymers in the gas and volatile organic compounds (VOCs) detections represents an advance in the development of the electronic noses. Polythiophenes show good thermal and environmental stability, are easily synthesized and they have been studied as gas and VOCs sensors using different principles or transduction techniques. Among these techniques, optical sensing has been attracted attention, mainly due to its versatility. However, conjugated polymer-based optical sensors are still less studied. This paper describes the use of two poly(3-alkylthiophenes) for VOCs optical detection. The sensing measurements were carried out using visible spectroscopy. Both polymers showed good sensitivity to the VOCs, showing fast and reversible responses with some hysteresis, and were unable to detect hydroxylated samples. Furthermore, it was demonstrated that the thickness of polymer films influences the intensity of the optical response. Although there is similarity in the superficial composition of the polymers films, demonstrated by their surface energies, they showed significant differences in their optical properties upon exposure to the VOCs.     

硅纳米线制成的纳米传感器

最新的研究表明:采用硅纳米线作为检测部件,利用其自身所特有的电学性质及高表面活性可制成有实用前途的纳米传感器。介绍了硅纳米线在合成纳米传感器方面的最新应用进展,对检测NH3气、水蒸汽、pH值、Ca2+及DNA等方面的应用做了较详细地阐述。     

常见浮选液位测量装置的分析及对比

为了解决浮选控制过程中的液位计选型问题,从现场应用出发,分析对比了常用的浮力式液位计、激光液位计、静压液位计、超声波液位计等浮选液位测量装置的基本结构、工作原理及现场应用情况。分析认为因传感器性能、附属装置稳定性、测量介质等不同,各测量装置均有优缺点,实际应用时应综合考虑现场浮选生产过程具体情况、维修条件、装置性能、安装使用费用等因素,选择合适的浮选液位测量装置。     

卟啉和金属卟啉配合物的合成及其在传感器中的应用

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。     

无线传感器网络被动红外目标跟踪技术研究

无线传感器网络的目标跟踪技术是目前研究的热点之一。被动红外传感器对活动的人具有较高的灵敏度,而目前被动红外多用于双元目标检测,并未实现目标定位,限制了被动红外的应用。本文提出了无线传感器网络的被动红外目标跟踪模型PITM。在该模型中,多个红外传感器节点通过协同可以确定目标的位置和运动速度。仿真实验表明,当节点密度为每1000m224个节点时,定位平均误差在0.5m左右,且节点密度越大,定位误差越小。