Ru (dip ) 2+ 3 络合物氧敏感膜的光降解特性研究

氧指示剂的光降解是影响荧光猝灭氧传感器光稳定性的主要因素.本文研究了Ru(dip)\+\{2+\}\-3络合物氧敏感膜光降解模型,给出了敏感膜光降解速率与激励光波长、强度及膜环境温度的依赖关系.     

光学氧传感器氧敏感膜的光降解

简要介绍基于荧光猝灭原理的光学氧传感器研制开发中的关键问题 ,氧敏感膜光降解的概念及其研究状况     

钌络合物合成氧敏感膜的光学与传感特性研究

基于钌络合物Ru(dpp)3Cl2的发光特性,制备了一种化学稳定性好、使用寿命长、荧光激发性能高的氧敏感膜.研究了敏感膜的透光特性,重点分析了荧光试剂浓度、液体温度、pH值、电路参数等因素对敏感膜荧光发射强度的影响,同时探讨了不同激发光源对敏感膜荧光性能及其使用寿命的影响,在此基础上,实现了氧敏感膜的特异性和对溶解氧的响应度检测.实验结果表明:制备的氧敏感膜对水体中的溶解氧响应度较好,检测误差保持在1％左右,在溶解氧/葡萄糖含量测定、微生物传感检测等方面有着较好的应用前景.     

光纤0_2/CO_2复合传感器的研制

本文报导一种新型的光纤氧、二氧化碳复合传感器.通过在同一敏感膜载体上固定两种不同的荧光试剂——芘丁酸及羟基芘三磺酸,制作了一种对氧和二氧化碳敏感的复合敏感膜.该传感器在医学临床检验范围内具有良好的线性,其测氧的分辩率是0.1％,测二氧化碳的分辩率是0.5％,响应时间短于1min.文中还讨论了三种敏感膜载体的比较及复合传感器测量进程中氧和二氧化碳的相互干扰问题.     

四对溴苯基铂卟啉PVC敏感膜氧传感器的研究

该文研制了一种新型氧敏感膜,其敏感物质为四对溴苯基铂卟啉,支持体系为PVC粉.该敏感膜是基于四对溴苯基铂卟啉在不同氧气浓度的环境中的荧光强度的变化而工作的.其最大激发波长与发射波长分别为515 nm和664 nm.文中检测了该敏感膜的稳定性,重现性等性质,发现其对分子氧的响应值I0/I100=52,其中I0是敏感膜在纯氮气氛围中的荧光强度,I100为其在纯氧气氛围中的荧光强度.该敏感膜具有良好的重现性及稳定性.     

光纤O2/CO2复合传感器的研制

本文报导一种新型的光纤氧 、 二氧化碳复合传感器。通过在同一敏感膜载体上固定两 种不同的荧光试剂—跪丁酸及狂基龙三磺酸, 制作了一种对‘氧和二羲化破敏感的复合敏感 膜( 该传感器在医学临床检脸范围内具有良好的线性, 其测氧的分辫率是# ( ?? ) , 测二氧化 破的分辫率是# ( ? 写, 响应时间短于+ , ?. 。文中还讨论了三种敏感膜载体的比较及复合传感 器浏量进程中氧和二氧化谈的相互干扰问题(     

Pt/LaF3敏感膜MIS型固态氧传感器研制

研究了可在室温下工作，且具有Ｐｔ／ＬａＦ３敏感膜的ＭＩＳ型固态氧传感器，讨论了它的敏感机理，测试并分析了传感器的响应特性。     

2002年《传感技术学报》第15卷1-4期总目录

第一期基于 Duffing方程参数敏感性提取谐振型传感器频率的仿真研究赵向阳 ,刘君华 ( 1 )………………………机器人触觉传感器力学建模与仿真李　嘉 ,刘文江 ,胡军 ,邱祖廉 ( 5 )…………………………………………一种新颖的光纤光栅位移传感的研究童峥嵘 ,黄勇林 ,蒙红云 ,董新永 ,开桂云 ,董孝义 ( 1 0 )…………………一种新型绝对式鉴幅型动态测角系统的研究郭　新 ,冯汝鹏 ( 1 4)………………………………………………Ru( dip) 2 + 3 络合物氧敏感膜的光降解特性研究杨建华 ,侯　宏 ,王　磊 ( 1 9)…………………………………梯度功能…     

用于挥发性有机气体测定的化学阻抗传感器

该文以碳粉掺杂的聚合物为敏感膜,以叉指电极为基底制作了测定挥发性有机气体的化学阻抗传感器.当敏感膜吸附有机气体时,敏感膜膨胀,导致膜中导电性的碳粉粒子距离增加,电阻也增加.同时.有机气体的吸附还引起敏感膜的介电常数改变,从而导致电阻、电容改变.通过传感器电阻电容的变化可以实现有机气体的定量测定.考察了敏感膜厚度、敏感膜中碳粉含量、及测定频率对传感器电阻电容响应的影响.该文还探讨了电阻和电容响应的机理.     

一种硅微谐振式压力传感器的敏感膜片设计

根据正方形膜片的变形和应力分布情况,提出了一种硅微谐振式压力传感器敏感膜片的设计方法,设计了两种正方形间接连接式压力敏感膜片.在相同的膜片面积下,新膜片与原有矩形间接连接式压力敏感膜片性能相近,为内部谐振器的多样化提供了基础.最后,就压力敏感膜片的工艺设计进行了探讨,认为采用正方形凸角补偿结构的〈110〉硅岛和采用边长补偿的〈100〉硅岛最适合间接连接式压力敏感膜片.     

Optochemical hydrogen peroxide sensor based on oxygen detection

A novel hydrogen peroxide sensor based on an optochemical oxygen sensor is presented. An oxygen sensitive membrane is covered with an additional layer containing inorganic catalysts which decompose hydrogen peroxide to water and oxygen. The oxygen is detected in the underlying oxygen sensitive membrane via luminescence quenching. The investigated concentration range for the reported sensor was between 0.1 and 2 wt.% hydrogen peroxide in water. Several catalysts were tested for this application with manganese dioxide being the preferred material. In addition to this, it was shown that by coating the sensor with a proper polymer layer, the hydrogen peroxide sensitivity could be improved up to five times compared to an uncoated sensor. The response times of the sensors depends on the type of covering layer, with the shortest response times being similar to that of uncoated sensors (t₉₅ was approximately 1 min for a change from 0 to 0.2 wt.% hydrogen peroxide in water).     

Optimisation of a polymer membrane used in optical oxygen sensing

A method for detection of viable cells utilises a sensor based on the optical measurement of oxygen consuming by cells. Changes in the oxygen level were measured via quenching of the fluorescence of an oxygen-sensitive fluorophor (Ru(dpp)₃Cl₂). The fluorescence lifetime changing was measured in accord with Stern–Volmer equation, using a phase-shift method. The fluorophor was embedded into a polysulfone membrane that is in contact with the cell medium. The sensitivity of oxygen sensor depends on behaviour of polysulfone membrane. Manufacturing method, type of polysulfone and concentration of fluorophor can also change this behaviour. These parameters were explored to obtain the optimum analytical performance, and the optimum sensitive membrane was chosen for 3 mmol/l concentration of fluorophor, when a linear plot was obtained with R=0.99987 for a sensitivity of 12.11±0.11 mV/% O₂ (n=5).     

Prolonged sensitivity of immobilized thylakoid membranes in cross-linked matrix to atrazine

Freshly prepared pea thylakoid membranes were immobilized in bovine serum albumin-glutaraldehyde cross-linked matrix (BSA-GA matrix) and their stability under long term storage was analyzed by Pulse-Amplitude-Modulated (PAM) chlorophyll fluorescence and photosynthetic oxygen evolution measured by oxygen rate electrode. The thylakoid membranes stored at 4 °C showed prolonged stability in BSA-GA matrix and additional adsorption on nitrocellulose membrane filters gave them more stability. The sensitivity of the parameters of the oxygen evolution of thylakoid membranes to atrazine increased with immobilization. The half-inhibition time for oxygen evolution and quantum efficiency of photosynthesis could be prolonged to more than 15 days. These results suggest that the immobilized thylakoid membranes in BSA-GA matrix can be used as biological receptor in biosensors for a long period of time (up to 25 days) applying the proposed new method for atrazine detection by using polarographic oxygen rate electrode. This method is more sensitive, faster and easier to use than other methods for detection of herbicides based on determination of the photochemical activity of photosystem II.     

Rationalization of the behaviour of a bi-label oxygen optical sensor

An oxygen optical sensor with two luminophores embedded in a polymeric matrix was prepared. The aim was to improve oxygen quantification by optimizing precision in the whole concentration range. The two luminophores behaved as if they were independent giving to the sensing layer enlarged working range with respect to the most sensitive membrane and improved precision with respect to the less sensitive membrane. Platinum(II) 5,10,15,20-tetraphenyl-21H,23H-porphyrin, palladium(II) 5,10,15,20-tetrakis(pentafluorophenyl)-21H,23H-porphyrin, ruthenium(II) (4,7-diphenyl-1,10- phenanthroline)₃(octylsulfate)₂ were used as luminophores and they were embedded either in polyvinylchloride or in polysulfone matrices. Their different life-times allowed preparing sensing membranes having optimized precision in the required concentration interval by proportioning luminophores amounts. A working curve indicated the most suitable membrane composition.     

一个基于粗集的决策树规则提取算法

决策树是数据挖掘任务中分类的常用方法。在构造决策树的过程中,分离属性的选择标准直接影响到分类的效果,传统的决策树算法往往是基于信息论度量的。基于粗糙集的理论提出了一种基于属性重要度和依赖度为属性选择标准的决策树规则提取算法。使用该算法,能提取出明确的分类规则,比传统的ID3算法结构简单,并且能提高分类效率。     

掺杂PdO敏感电极对丙烯的气敏性能研究

为了研究并提升氧化钯(PdO)敏感电极的气敏性能,采用Ni,La和Mg元素对PdO进行掺杂.通过掺杂前后PdO的表征实验对比,发现掺杂作用不仅改变晶格参数,同时也影响晶体中的缺陷.在对丙烯气敏测试中,Ni和La掺杂的PdO敏感电极提高了传感器气敏灵敏度.对于掺杂提高气敏响应的机理,我们根据不同元素掺杂对PdO气敏反应的不同作用,讨论了氧化物缺陷对PdO催化活性的影响.晶体中的氧缺陷可以提高氧化物的催化活性,使传感器具有较高的灵敏度.具有掺杂PdO敏感电极对氧气和多种气体的选择性测试,表现出对丙烯气体具有较高的选择性.     

Nonlinear MPC for the airflow in a PEM fuel cell using a Volterra series model

The particular industrial interest in fuel cells is based on the possibility to generate clean energy both for stationary and automotive applications. Performance and safety issues of fuel cells are closely related to the control strategy used for the fuel and oxidant supply. In PEM (polymer electrolyte membrane or proton exchange membrane) fuel cells the oxygen excess ratio expresses the proportion between oxygen reacting in the cells and oxygen entering the stack and represents a decisive variable for the mentioned issues. This work is focused on the design of a nonlinear model predictive control (NMPC) strategy manipulating the air flow rate in order to maintain the oxygen excess ratio in a desired value, both for safety and performance reasons. The designed NMPC, based on a second order Volterra series model, was implemented on a commercial fuel cell. The proposed NMPC strategy is validated in experiments and compared to a linear model predictive controller and to the original built-in controller.     

聚3—己基噻吩及其掺杂TiO2材料对NO2的气敏特性

制作了一种工作于室温下的NO2气体传感器。该传感器以有机聚合物聚3—己基噻吩(P3HT)为敏感材料,以聚对苯二甲酸乙二醇酯(PET)薄膜为柔性衬底。对敏感膜进行了SEM表征。室温下,对不同体积分数的NO2进行了测试,对器件尺寸的影响进行了分析,并对响应规律进行了总结。经实验,对NO2测试下限可达到0.2×10-6。为提高敏感性、减小恢复时间,尝试对敏感膜掺杂TiO2,并同未掺杂的敏感膜进行实验比较,发现对体积分数1.5×10-6的NO2,掺杂TiO2可将敏感性提高8%,恢复性也有明显改善,对周期为1060 s的循环测试表明:掺杂TiO2下阻值基本能完全恢复。