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991.
The new enhancement in the determination of pH using optical fiber system is described here. This work uses the membrane made of cellulose acetate membrane for reagent immobilization and congo red (pKa 3.7) and neutral red (pKa 7.2) as pH indicators. An effective covalent chemical binding procedure is used to immobilize the indicators. The response time, reversibility, linear range, reproducibility, and long-term stability of fiber optic sensor with congo red as well as neutral red have been determined. The linear range measured for the sensor based on the congo red and neutral red is 4.2-6.3 and 4.1-9.0, respectively. The response time of sensor membrane is measured by varying the substance pH values between 11.0 and 2.0. 相似文献
992.
993.
B. G. M. Vandeginste G. Kateman J. K. Strasters H. A. H. Billiet L. de Galan 《Chromatographia》1987,24(1):127-134
Summary The mathematical resolution of overlapped chromatographic peaks obtained in HPLC with a diode array UV detector has received
considerable attention recently. The purpose of the proposed methods is the quantitation and identification of unknown solutes
in complex mixtures by an efficient use of all available data.
Basically two approaches have been proposed: the first one resolves the concentration profiles and calculates the pure spectra
by applying a minimal number of assumptions, which is denoted self-modeling-curve resolution. The second one is based on a
match of pure spectra available in a spectral library with the measured mixture spectra.
In this paper both approaches are evaluated with respect to their performance to provide the pure spectra and an accurate
quantitation of the concentrations. 相似文献
994.
WANG Jian-ya FANG Zhao-lun . Research Center for Analytical Sciences Northeastern University Shenyang P. R. China . School of Petrochemical Engineering Shenyang University of Technology Shenyang P. R. China 《高等学校化学研究》2006,22(3):287-291
Introduction Determinationofglucoseisrequiredinmedicine industry,foodindustry,clinicaldiagnosisaswellas variousresearchfields.Therefore,intensiveefforts havebeendirectedtothedevelopmentofanalytical methodsfordeterminationofglucose,suchasthose basedonbiose… 相似文献
995.
996.
997.
Simon Johnstone John I. Sachinidis Richard D. Shalders Peter A. Tregloan 《Journal of solution chemistry》1995,24(8):795-811
The design and operation of a computer controlled continuous dilution dilatometer utilizing a diode array detection system is presented. To test the accuracy and reproducibility of the technique, apparent molar volumes of dilute aqueous solutions of potassium ferricyanide and potassium ferrocyanide have been measured. To provide supporting data for high pressure studies of reaction volumes and molar volume change in solutions of high ionic strength, study of these electrolytes was extended by dilution into 0.1M and 1.0M potassium nitrate solutions rather than extrapolation to zero ionic strength as is normal. In addition, the system has been used to determine reaction volumes of some acid-base reactions by direct measurement, using the equipment as an automatic titration dilatometer. 相似文献
998.
基于4400系统,通过引入光电二极管列阵作为传感器,构造了具有光学多道分析功能的信号处理系统。利用该系统对实际的激光空间分布进行了描绘,给出了高斯场分布的相应参数。通过进一步观测p偏振光在K9玻璃上下表面反射光强比(γ)的角度调制曲线,获得了玻璃表面层的光学参数。实验结果表明,该系统测量精度高,可应用在激光时间信号及空间场分布的表征与测量领域。 相似文献
999.
Jean-Luc Tissot 《Comptes Rendus Physique》2003,4(10):1083-1088
The emergence of uncooled detectors has opened new opportunities for IR detection for both military and commercial applications. Development of such devices involves a lot of trade-offs between the different parameters that define the technological stack. These trade-offs explain the number of different architectures that are under worldwide development. The key factor is to find a high sensitivity and low noise thermometer material compatible with silicon technology in order to achieve high thermal isolation in the smallest area as possible. Ferroelectric thermometer based hybrid technology and electrical resistive thermometer based (microbolometer) technology are under development. LETI and ULIS have chosen from the very beginning to develop first a monolithic microbolometer technology fully compatible with commercially available CMOS technology and secondly amorphous silicon based thermometer. This silicon approach has the greatest potential for reducing infrared detector manufacturing cost. After the development of the technology, the transfer to industrial facilities has been performed in a short period of time and the production is now ramping up with ULIS team in new facilities. LETI and ULIS are now working to facilitate the IRFPA integration into equipment in order to address a very large market. Achievement of this goal needs the development of smart sensors with on-chip advanced functions and the decrease of manufacturing cost of IRFPA by decreasing the pixel pitch and simplifying the vacuum package. We present in this paper the technology developed by CEA/LETI and its improvement for being able to designs 384×288 and 160×120 arrays with a pitch of 35 μm. Thermographic application needs high stability infrared detector with a precise determination of the amount of absorbed infrared flux. Hence, infrared detector with internal temperature stabilized shield has been developed and characterized. These results will be presented. To cite this article: J.-L. Tissot, C. R. Physique 4 (2003). 相似文献
1000.