β"-Al2O3固体电解质CO2传感器气敏性能的研究

采用β-Al2O3作为固体电解质,BaCO3-Li2CO3二元复合碳酸盐作为辅助电极,组成了一种开放型的CO2传感器.在CO2浓度为1.6×10-22%～2%的范围内对传感器进行了气敏性能测试,400℃、450℃及500℃时测得的传感器电动势与能斯特方程符合得很好,并且响应迅速.另外,在CO2浓度固定不变的情况下,还观察了O2和N2的浓度对传感器的影响.     

制备参数对碱式碳酸铜形成过程的影响

采用IR、XRD、SEM、摄相等技术详细研究了以碳酸钠和硫酸铜为反应原料,2者的物质的量之比、反应温度、溶液pH、原料滴加顺序和滴加速度等参数对碱式碳酸铜(Cu2(OH)2CO3)形成过程的影响。结果表明,当 Na2CO3与CuSO4的物质的量之比为1.2~1.4、温度328~353 K、以CuSO4滴入Na2CO3溶液(正滴,滴速2.0 mL/min)时可以得到浅绿色Cu2(OH)2CO3,反应体系的最终pH为8.90~9.15。反应过程中溶液pH的控制、原料滴加顺序及滴加速度对生成产品物相有重要的影响。当溶液pH控制为7时可以得到Cu2(OH)2CO3。当溶液控制pH为8~9时得不到Cu2(OH)2CO3。在与正滴顺序相反的情况下,即将Na2CO3滴入CuSO4溶液、滴速为2.0 mL/min得不到Cu2(OH)2CO3,但当Na2CO3滴加速度降为0.5 mL/min可得到纯相Cu2(OH)2CO3。     

全固态穿刺复合Sb/Sb_xO_y-pH传感器的制备及性能研究

报道了一种直接测定固体、半固体及糊状物表面和内部pH的全固态复合Sb/SbxOy-pH传感器,研究了该传感器的制备工艺、性能、测试条件等。该pH传感器线性范围2～12,响应斜率-58.98mV/pH,响应时间≤30s,漂移≤0.1pH/24h,用于实际样品与pH玻璃电极对照,ΔpH≤0.1。通过交流阻抗技术,探讨了电极的动力学机理。     

金属有机化学气相沉积法制备SnO2/MCM-41半导体传感器及其性能研究

采用金属有机化学气相沉积(MOCVD)法制备了SnO2/MCM-41半导体传感器, 考察了沉积时间和沉积温度对SnO2/MCM-41半导体传感器的SnO2沉积量、比表面积和孔径的影响; 研究发现, 随着SnO2沉积量的增加, 孔径有规律地下降, 说明SnO2较均匀地沉积在介孔分子筛MCM-41的孔道之中. SnO2/MCM-41半导体传感器对CO和H2具有较高的传感性能, 其传感性能的大小与CO和H2的浓度成正比.     

基于负温度系数热敏电阻的催化燃烧型一氧化碳传感器

介绍一种能检测0.0232 g/m3CO的新型催化燃烧型传感器。这种传感器使用电阻温度系数高的负温度系数热敏电阻(NTCT)代替传统的铂丝线圈。传统的催化燃烧型传感器只能检测百分浓度的可燃气体,而基于NTCT的催化燃烧型CO传感器可以检测到0.0232 g/m3CO气体。当桥电压为9 V时,传感器输出信号与CO浓度在0.0232~0.58 g/m3之间具有良好的线性关系。传感器对0.58 g/m3CO的响应和恢复时间分别为50和120 s。考察了传感器的选择性和长期稳定性,结果表明:传感器对甲烷等气体具有较好的选择性,老化处理后的传感器,连续观察100 d,对CO的响应强度未发生明显下降。     

醇胺溶液吸收二氧化碳的实验研究

CO2的减排和有效利用受到人们的广泛关注.以二乙醇胺(DEA)、三乙醇胺(TEA)、N-甲基二乙醇胺(MDEA)溶液为对象,采用鼓泡吸收装置考察了醇胺的种类及浓度对CO2吸收速率和吸收容量的影响,研究了吸收前后溶液pH的变化,以及醇胺溶液再生后的情况.实验表明,醇胺溶液浓度增大有利于CO2的吸收,相同条件下DEA和TEA的吸收效果好于MDEA,醇胺溶液吸收CO2后pH由接近于11降至7左右,TEA的再生效果好于DEA.     

键合法制备高亲水性光化学pH传感器敏感膜及性能研究

采用丙烯酰胺为偶合剂,以Fe2+/H2O2为引发剂,将邻甲酚红通过表面接枝聚合固定于交联聚乙烯醇膜表面,制备了一种可用于光化学pH传感器的pH敏感膜。性能测试表明,此膜具有pH响应范围宽(pH7.97～12.26)、响应时间快(<25s)、耐盐性好、可逆重复性及光和贮存稳定性良好,制备方法简单的优点。实验表明,此膜可用于光化学pH传感器。     

二氧化碳缓冲溶液缓冲原理的数字化解析实验*

利用传感器数字化技术,分析室温下碳酸氢钠稀溶液直接吸收或释放二氧化碳气体的行为、pH及其变化趋势,设计数字化实验,为碳酸氢钠溶液在生物上作为二氧化碳缓冲液的行为提供化学实验验证。进行热力学计算,为其缓冲原理提供化学理论支撑。实验证明,碳酸氢钠稀溶液是构建二氧化碳缓冲液的充要条件,其作用原理是通过自偶电离建立碳酸氢钠碳酸钠缓冲对,从而与环境中的二氧化碳建立溶解平衡,其总方程式为:2HCO-3(aq)CO2-3(aq)+H2O(l)+CO2(g)。     

CO2-水-页岩相互作用的研究现状及展望

简要综述了CO2、水和页岩间矿物的相互作用,分析了CO2注入到地下进入页岩层后,地下含水层pH值的变化,并根据页岩层的矿物学组成分为黏土矿物和脆性矿物,较为详细地描述了CO2与黏土矿物和脆性矿物之间发生的地球化学反应,概述了此反应对页岩层孔隙度和渗透率的影响。同时,也讨论了CO2增强页岩气开采的现实问题及发展趋势,为今后的研究提供了参考。     

全固态复合Ir/IrOx-pH传感器的研制及应用

报道了一种用于直接测定固体、半固体及糊状物表面和内部pH的新型全固态复合pH传感器,建立了原位无破损pH测定的新方法。详细地探索了pH传感器的制备工艺、性能、测试条件和干扰物的影响。pH传感器线性范围1.0~13.0,响应斜率56±1.0 mV/pH,温度系数-0.782 mV/℃,与pH玻璃电极结果对照,△pH≤0.1。该pH传感器的实际应用结果令人满意。     

A Multivariate Liner Model for Calculating Response Feature Parameters of Chemical Sensor Based on Fluorescence Quenching for Analytes

The chemical membrane sensors based on fluorescence quenching are the important field of the chemical sensors, it is conducive to the development of the chemical sensors to inquire into their fluorescence quenching mechanism and evaluate their response parameters.     

Phthalocyanines as Sensitive Materials for Chemical Sensors

This paper provides a review of phthalocyan- ines suitable for the development of chemical sensors. Phthalocyanines may be utilized for different types of chemical sensors, including in particular electronic conductance sensors [such as semiconductive, field-effect transistor (FET), solid-state ionic and capacitance sensors], mass-sensitive sensors utilizing a quartz crystal microbalance (QCM) and surface acoustic-wave (SAW) sensors, and optical sensors. The phthalocyanines used are discussed in terms of their physical and chemical properties, as well as their sensitivity, selectivity and reversibility towards the detection of NO₂ and organic solvent vapours. The interaction mechanism between phthalocyanine films and analyte molecules is also discussed.     

An attempt to create stable biomimetic sensors for express analysis of hydrogen peroxide in water solutions

The physico-chemical properties of a new type catalase sensor, the so-called biomimetic sensors, modulating some of the catalase biosensor functions were investigated. These sensors have technological advantages over their biological analogs because of properties usually attributed to chemical sensors. The developed electrochemical system lies between bio- and chemical sensors.     

Multi-Analyte Sensing: From Site-Selective Deposition to Randomly-Ordered Addressable Optical Fiber Sensors

In this report we review the progress in the development of imaging fiber chemical sensors. Emphasis is placed on the chemical sensor component and the fabrication of architectures appropriate for multi-analyte sensing, such as optical fiber sensors. Two main approaches in the fabrication of such sensors will be highlighted: first, sensors made with spatially-resolved sensing sites by site-selective polymerization, second, sensors prepared by random distribution of microsphere sensors on an optical imaging fiber containing thousands of μm-scale wells. Examples of each are given.     

非质量效应压电化学传感的应用与发展

压电化学传感器在学术界通常称为压电石英微平天,归属于质量传感器范围,但是在液相中,这种传感器还要受到液相物理化学特性参量的影响,据此,提出与发展了区别于常规质量响应型压电传感的另一类非质量响应型压电传感检测技术,本文论述了在相应领域中的应用研究,其中不少领域,传统的微天平型压电传感器根本不适用,或者传感性能不如新型的基于非质量效应响应机理的压电传感器。     

Fluorescent sensors for the detection of chemical warfare agents

Along with biological and nuclear threats, chemical warfare agents are some of the most feared weapons of mass destruction. Compared to nuclear weapons they are relatively easy to access and deploy, which makes them in some aspects a greater threat to national and global security. A particularly hazardous class of chemical warfare agents are the nerve agents. Their rapid and severe effects on human health originate in their ability to block the function of acetylcholinesterase, an enzyme that is vital to the central nervous system. This article outlines recent activities regarding the development of molecular sensors that can visualize the presence of nerve agents (and related pesticides) through changes of their fluorescence properties. Three different sensing principles are discussed: enzyme-based sensors, chemically reactive sensors, and supramolecular sensors. Typical examples are presented for each class and different fluorescent sensors for the detection of chemical warfare agents are summarized and compared.     

基于荧光猝灭原理的光纤化学传感器定量分析模 型的建立与应用

根据光纤化学传感器的结构与信号传输特征,推导并建立了适合于定量描述基于荧光猝灭原理的光纤化学传感器对待测物响应的非线性数学模型。以此为基础,为更加简捷、直观地反映响应信号与待测物浓度的函数关系,建立可线性化的回归方程,准确预报待测物的浓度,提出了多模型回归技术建立此类光纤化学传感器定量分析模型的方法。为难定量分析模型的适用性,将该法应用于芘丁酸光纤化学传感器对甲硝唑、呋喃妥因和氧氟沙星等待测物响应的最佳数学模型的选择之中。结果表明,所选的数学模型对各待测物在一定范围内的浓度都能进行准确的预报。     

Chemical sensors and their systems

The review presents a short record of the evolution of chemical sensors (ion selective electrodes) and multisensor systems of an electronic tongue type, based on the organization principles similar to those of biological sensors. The main types of chemical sensors and multisensor electronic tongue combinations elaborated today are considered along with sensitive materials used in them. Recent advances in chemical sensors, for example, lower detection limits and so-called true selectivity are scrutinized. Also, some widespread analytical applications of electron tongues, including those for the identification and classification of liquid media, for the quantification of various components in there, for the control of industrial processes, as well as the type and intensity evaluation of the taste of food and medications are discussed.     

Optical sensors for dissolved ionic chemical species

The sensing of ions in various media is a continuing problem that often requires new techniques as existing sensors may be inadequate for a particular example. Chemical sensors based on fibre optics have recently been the subject of considerable interest, as they have a number of advantages over conventional systems. This paper reviews those optical fibre chemical sensors that have been developed for the sensing of ionic chemical species in solution.     

Biological and chemical sensors based on graphene materials

Owing to their extraordinary electrical, chemical, optical, mechanical and structural properties, graphene and its derivatives have stimulated exploding interests in their sensor applications ever since the first isolation of free-standing graphene sheets in year 2004. This article critically and comprehensively reviews the emerging graphene-based electrochemical sensors, electronic sensors, optical sensors, and nanopore sensors for biological or chemical detection. We emphasize on the underlying detection (or signal transduction) mechanisms, the unique roles and advantages of the used graphene materials. Properties and preparations of different graphene materials, their functionalizations are also comparatively discussed in view of sensor development. Finally, the perspective and current challenges of graphene sensors are outlined (312 references).