光纤NH_3气体传感器

设计开发了一种光纤NH3气体传感器．其探头结构采用指示剂＋内充液型。将指示剂吸附于阴离子交换膜上,敏感膜固定于光纤末端,气体穿过透气膜进入探头,使探头内部电解质溶液的pH值发生变化,从而改变了内充液中指示剂的共轭酸碱异构体的浓度比,检测限为2μmol／L．     

有害气体检测的光纤传感技术发展

光纤气体传感器具有易于小型化、可遥测、灵敏度高、响应快等诸多优点.根据传感原理,概述了有害气体检测的光纤传感器,包括折射率变化型光纤气体传感器、倏逝波光纤气体传感器、表面等离子共振光纤气体传感器、光声光纤气体传感器、多孔光纤气体传感器,以及吸收型光纤气体传感器、荧光型光纤气体传感器、染料指示剂型光纤气体传感器.简要介绍了光纤气体传感器的发展.     

光纤pH传感器

本文叙述了一种在光纤端面放置固定化pH染料指示剂的反射式光纤传感器,其探头结构是通过共价结合法把酚红、溴酚兰和百里酚兰等三种染料固定在丙烯酰胺微球上形成亲水凝胶状指示剂,用聚四氟乙烯网膜定位放置,同光纤端面间留有一定缝隙,便于指示剂与被测溶液的离子交换,反应。文中给出这种光纤传感器的全部性能参数,其测试范围3.0—5.0pH(溴酚兰指示剂);7.0—8.5pH(酚红指示剂)和8.0—10.0pH(百里酚兰指示剂);灵敏度66.6mV/pH;精度优于0.05pH;相关系数达99.9％;重复性0.013mV;响应时间(90％)对酚红指示剂为2min,对百里酚兰1min;滞后为0.52％;稳定性为0.015pH/h,该器件性能优良、制造简单,具有实用价值。     

高分子功能材料及在传感器中的应用─气体传感器(连载二)

介绍了有机高分子气体传感器的敏感材料种类、结构特征、检测方式，并重点介绍了几种气体传感器的性能、特点。对今后研究方向提出了看法。     

高分子功能材料及在传感器中的应用

介绍了有机高分子气体传感器的敏感材料种类，结构特征，检测方式，并重点介绍了几种气体传感器的性能，特点，对今后研究方向提出了看法。     

厚膜气体传感器的研究

本文报导采用典型的微电子学工艺一丝网漏印法制备以SnO_2为基的厚膜气体传感器。研究了不同掺杂剂和玻璃料对厚膜气敏材料性能的影响,结果显示ZrO_2掺杂有助于提高厚膜气体传感器对一氧化碳和乙醇的选择性,而且气体传感元件的厚膜工艺设备筒单,便于生产。     

金属氧化物微气体传感器制备技术的研究进展

阐述了金属氧化物微气体传感器制备技术的最新研究进展,介绍了气体传感器的气敏膜表面化学处理、气氛沉积、复合气敏膜、热氧化成膜技术、异形电极技术、显微铸造微传感器阵列技术和溶胶凝胶提拉成膜技术,分析了各自的特点,并提出了存在的问题和今后的发展方向。     

光纤CO气体检测系统的研究

基于CO气体的光谱吸收特性,设计了一种带有参比气室的光纤CO气体在线实时检测系统。采用双波长差分检测技术,有效消除了由光源、光纤和探测器的不稳定所引起的检测误差,提高了检测灵敏度。给出了该光纤CO气体检测系统的实验结果,结果表明：该传感器结构简单、外形尺寸小、性能稳定、抗干扰能力强,具有广阔的应用前景。     

光纤氧传感器的传感膜制备及弱荧光检测

研制了一种基于荧光猝灭原理的光纤氧气传感器。制备了醋酸纤维素传感膜并研究了其性能,结果表明,该传感膜均匀、稳定、响应快。采用锁相放大技术,实现了对荧光信号的检测。该传感器具有较高的检测精度、较好的重复性和稳定性。     

光纤氧气传感器的传感膜制备及弱荧光检测

研制了一种基于荧光猝灭原理的光纤氧气传感器。制备了醋酸纤维素传感膜并研究了其性能,结果表明,该传感膜均匀、稳定、响应快。采用锁相放大技术,实现了对弱荧光信号的检测。该传感器具有较高的检测精度、较好的重复性和稳定性。     

光纤传感器进展

重点描述了医学和航空工业中的几种光纤传感器,以及气体和温度分布传感器的目前状况。     

Miniature interferometric humidity sensors based on silica/polymer microfiber knot resonators

In this paper, two fiber-optic interferometric humidity sensors based on silica/polymer microfiber knot resonators (SMKR/PMKR) are reported. These tiny humidity sensors are directly fabricated by using silica/polymer microfibers without any humidity-sensitive coating. The silica microfiber knot resonator sensor has a humidity sensitivity of ∼12 pm/10%-RH within a linearity range from 15%-RH to 60%-RH, while the polymer microfiber knot resonators sensor has a humidity sensitivity of ∼88 pm/10%-RH, with a linearity range from 17%-RH to 95%-RH. The temporal response of the PMKR sensor is <0.5 s. Such types of humidity sensors have advantages of easy fabrication, fast response, extremely compact size, stable and low cost, they would find potential applications in micro-scale humidity sensing.     

飞行器健康管理中传感器的应用及趋势分析

传感器技术是飞行器健康管理实现的基本使能技术。详述了光纤传感器、微机电传感器在飞行器健康管理中的应用现状,并讨论了传感器在该领域中的发展趋势。     

Low-cost fiber-optic waveguide sensor for the colorimetric detection of ammonia

We present the development and characterization of a low-cost fiber-optic colorimetric gas sensor for ammonia combined with the electronic circuitry for measurement control and RFID communication. The gas sensor detects ammonia using a 300?μm polyolefin fiber coated with a gas-sensitive polymer film. The spectral and time-dependent sensitivity of various polymer films was tested in transmission measurements at λ?=?590?nm. A prototype of the gas sensor was tested under realistic measurement conditions, i.e. battery-driven and in a completely autonomous mode. The sensor system showed good sensitivity to the ammonia concentrations and response times in the order of minutes. The achievable power consumption was below 100?μW. Bromophenol blue-based films showed a strong reaction to ammonia, with saturation concentrations around 1,000?ppm and response times of about 15?s to 100?ppm. The colorimetric reaction was simulated using a simple kinetic model which was in good agreement with the experimental results.     

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.     

Irreversible sensing of oxygen ingress

Absorption-based opto-chemical sensors for oxygen are presented that consist of leuco dyes (leuco indigo and leuco thioindigo) incorporated into two kinds of polymer matrices. An irreversible and visible color change (to red or blue) is caused by a chromogenic chemistry involving the oxidation of the (virtually colorless) leuco dyes by molecular oxygen. The moderately gas permeable copolymer poly(styrene-co-acrylonitrile) and a highly oxygen-permeable polyurethane hydrogel, respectively, are used in order to increase the effective dynamic range for visualizing and detecting oxygen. We describe the preparation and properties of four different types of such oxygen sensors that are obtained by dip-coating a gas impermeable foil made from poly(ethylene terephthalate) with a sensor layer composed of leuco dye and polymer.     

具有快速响应的pH光纤传感器

研制出一种利用高分子聚合物薄膜作为基底材料的光纤pH传感器,它是将刚果红染料试剂固定化到经化学处理过的高聚物薄膜上而制成的。实验中,运用了双臂反射传感方式和流动注射进样法。该传感器具有灵敏度高,牢固耐用,尤其是响应时间短(<0.03min)等特点。     

现代军用MEMS惯性传感器技术进展

现代化军事需求小型惯性传感器。技术已成熟的惯性导航和制导系统包括机械陀螺、环形激光陀螺(RLGs)、光纤陀螺(FOGs)以及半球共振陀螺(HRGs)。现在主要用于军事的还有微机电系统(MEMS)陀螺仪和加速计。采用光子晶体光纤(PCFs)的干涉光纤陀螺(IFOGs),即PC—IFOGs。重点阐述MEMS/集成光(IO)波导惯性传感器技术进展。分析小型陀螺仪和加速计技术发展前景及在未来快速反应,精确打击中的作用。     

基于SAW表面气液相效应和GC分离柱的气敏传感器

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。     

A low-power micromachined MOSFET gas sensor

This paper reports on the design, fabrication, and characterization of the first low-power consumption MOSFET gas sensor, The novel MOSFET array gas sensor has been fabricated using anisotropic bulk silicon micromachining. A heating resistor, a diode used as temperature sensor, and four MOSFETs are located in a silicon island suspended by a dielectric membrane. The membrane has a low thermal conductivity coefficient and, therefore, thermally isolates the electronic components from the chip frame. This low thermal mass device allows the reduction of the power consumption to a value of 90 mW for an array of four MOSFETs at an operating temperature of 170°C. Three of the MOSFETs have their gate covered with thin catalytic metals and are used as gas sensors. The fourth one has a standard gate covered with nitride and could act as a reference. The sensor was tested under different gaseous atmospheres and has shown good gas sensitivities to hydrogen and ammonia. The low-power MOSFET array gas sensor presented is suitable for applications in portable gas sensor instruments, electronic noses, and automobiles