Sensor technology applications

H. Baltes, W. Gopel, and J. Hesse, Sensors Update Sensor Technology - Applications - Markets. (Series eds.), VCH-Wiley, Weinheim, Vol. 1,19%, Vol. 2,1996... 

Gdpel, W. and Reinhardt, G. Metal oxide sensors new devices through tailoring interfaces on the atomic scale. In Sensors Update Sensor Technology —Applications — Markets, Baltes, H., Gdpel, W, and Hesse, J., Eds. VCH Weinheim, 1996, Vol. l,pp. 49-120. 

Committee on New Sensor Technologies Materials and Applications, National Materials Advisory Board, Commission on Engiueeriug and Technical Systems, National Kesearch Council Keport Expanding the Vision of Sensor Materials, National Academy Press, Washiagton, D.C. 1995, pp. 33-45. 

Titanium dioxide exists in nature as three different polymorphs rutile, anatase and brookite. This material has been extensively studied during the last few decades due to its interesting physical properties and numerous technological applications. Rutile and anatase (a popular white pigment) are widely used in photocataly s and as sensors. Both of them have had new structural and electronic applications suggested recently (see for a review). 

Guizard, C., Bac, A., Barboiu, M. and Hovnanian, N. (2001) Hybrid organic-inorganic membranes with specific transport properties. Applications in separation and sensors technologies. Separation and Purification Technology, 25, 167-180. 

Over the last several years, the number of studies on application of artificial neural network for solving modeling problems in analytical chemistry and especially in optical fibre chemical sensor technology, has increase substantially69. The constructed sensors (e.g. the optical fibre pH sensor based on bromophenol blue immobilized in silica sol-gel film) are evaluated with respect to prediction of error of the artificial neural network, reproducibility, repeatability, photostability, response time and effect of ionic strength of the buffer solution on the sensor response. 

As opposed to conventional analytical techniques, optical sensors and biosensors, particularly those employing absorption and fluorescence-based sensing materials potentially allow for measurement through transparent or semi-transparent materials in a non-destructive fashion4, 5> 9 10. Chemical sensor technology has developed rapidly over the past years and a number of systems for food applications have been introduced and evaluated with foods. 

It should be noted, however, that applicability of the thin-film optic-fiber sensor technology to pipelines for leak detection is still a challenge because pipelines are hundreds (even thousands) mile long. Additional research is needed to identify and develop sensors technologies for hydrogen leak detection along the pipeline. 

Temperature control is one of the longest established and most important functions in household appliances. One example of modern thin film fabrication technology of platinum temperature sensors with application examples in the kitchen in hot plates and ovens is given in Chapter 5.1. 

One of the key trends of sensor technology will he in modularisation of the technology steps in order to provide quasi-customized solutions without the need for a complete development. A modularisation of the sensor hardware in combination with standardization attempts are also being followed, but are deemed too expensive for the use in many applications, without a significant customisation advantage. 

Among all Fe(II) spin crossover compounds known to date, the extensively studied polymeric [Fe(4-R-l,2,4-triazole)3](anion)2 systems (R=amino, alkyl, hydroxyalkyl) appear to have the greatest potential for technological applications, for example in molecular electronics [1, 24, 25] or as temperature sensors [24, 26]. This arises because of their near-ideal spin crossover characteristics pronounced thermochromism, transition temperatures near room temperature, and large thermal hysteresis [1, 24, 27]. 

In this chapter we begin by discussing these atmospheric limitations, since they permeate the whole technology of MMW, sub-MMW, and THz technology. We then discuss MMW and THz sources, detectors, and systems in separate sections. Finally, we present some results obtained using sensors operating in these bands. These results show the connection between this sensor technology and applications to security. 

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