Sensor principle

Adequate techniques to accurately and selectively detect concentration levels are available, but are mostly expensive, slow, and complex. Cheaper sensors are available, but the working principle is usually not very selective. A wealth of different sensing techniques exists where typical sensor principles rely on changes in... 

Another way to achieve high detergency performance while keeping environmental impacts low is by making intelligent products with built-in sensor functions. In these applications, the products can respond to external stimuli and fulfil their task. The inherent sensoric principles of two recent innovations, detergent tablets and dishwashing tablets with built-in rinse aid, will be discussed. 

The sensoric principle of the dynamic bubble-pressure tensiometer is based on the differential Laplace pressure between two capillaries from which a controlled gas flow is released. At the lower end of a capillary which points into the liquid, a gas bubble is formed which increases its radius with increasing gas pressure (see... 

Depending on the gas type and application, different gas detection and sensor principles may be suitable. Beside the price, there are other parameters like accuracy, power consumption, long-term stability, lifetime, selectivity and sensitivity which have to be taken into account. However, whether a sensor is developed into a product depends on the relation between additional functionality and additional cost. In the subsequent chapters we intend to give an overview of common sensor principles and their potential use in household appliances. In order to give some information about existing (commercialized) sensors and sensor systems each subchapter is completed by an amendment listing a selection of relevant gas sensor products. 

In this sub-chapter we intend to give an overview of household appliances using the different gas sensor principles mentioned in the previous chapters. The appliances can be divided into two categories gas sensors for safety and for comfort. Natural gas and CO-alarm systems for example are safety-relevant whereas air quality measurement, control of self-cleaning of ovens etc. are more or less a matter of comfort or energy-saving. 

This patented sensor principle allows the integration of the sensor inside a compact friction damper. Compared with the limited space inside the damper, a maximum usable measuring range could be achieved. 

Gauglitz, G., Direct optical sensors principles and selected applications, Anal. Bioanal. Chem. 2005, 381, 141 155... 

TMM handles thin metallic films as well, as they are used in lO-sensors based on surface-plasmon-polaritons (SPP). SPPs appear at the dielectric-metal interface for TM polarization, exclusively. The sensor principle is to have a waveguide mode and the SPP close to resonance, and screen the resonance vs. angle or vs. wavelength to detect refractive index changes of the cladding. Figure 4 shows the resonance of the absorption vs. the... 

The predictive power of the luminescent PET sensor principle is again apparent here. Further, the benzocrown ether and the amine receptors would selectively bind Na" and H, respectively. A remarkable feature here is that no molecular wiring is needed to allow the human operation of this two-input molecular device. The device self-selects its own ion inputs into the appropriate signal channels by means of the chemoselective receptor modules. Since the output signal is fluorescence, even a single molecule can interface with detectors in the human domain, including the dark-adapted eye. Tanaka s 45 is another example where fluorescence quenching is achieved only when Ba and SCN are present. This was mentioned in Section 6. Similarly, several sensor systems—1,17, and 21—could be employed... 

Type of Sensor Principle of Operation Accuracy, Range, etc. Comments... 

Design of Sensitive Drug Sensors Principles and Practice... 

J. C. Owicki, L.J. Bousse, D.G. Hafeman, G.L. Kirk, J.D. Olson, H.G. Wada and J.W. Parce, The light-addressable potentiometric sensor principles and biological applications, Anna. Rev. Biophys. Biomol. Struct., 23 (1994) 87-113. 

Fluorescent PET (photoinduced electron transfer) sensors are considered to be those molecular systems where the binding of ions and other species leads to the perturbation of the competition between the de-excitation pathways of fluorescence and electron transfer. The early developments in this field are traced and the design logic of these sensors is detailed. A variety of examples drawn from different areas of chemistry are classified according to the fluorophore-spacer-receptor format and their photophysical behaviour is rationalized in terms of fluorescent PET sensor principles. Cases are pointed out where such experimental data are unavailable but desirable. During these discussions, the relevance of twisted fluorophore-receptor systems and the contrast with integrated fluorophore-receptor systems is noted. The utility of the fluorescence on-ofP phenomenon in these PET sensors for the area of molecular photoionic devices is pointed out. 

Grieshaber D, MacKenzie R, Voros J, Reimhult E (2008) Electrochemical biosensors -sensor principles and architectures. Sensors 8 1400-1458... 

Sensor Principles Based on High-Refractive-Index Optical Waveguides... 

High-refractive-index materials enable the investigation of bioreactions at the surface within the evanescent field. Various sensor systems were developed with the advantage of high sensitivity and measurement in the presence of the sample without any rinsing. The sensor principles can be divided into label-free sensor systems where the determination of the effective refractive index is the pivotal parameter and systems based on surface-confined fluorescence excitation where the marker molecule is solely detected. 

Amperometric Sensors Principle and Evolution of Enzyme Electrodes... 

Figure 1.1 Sensor principles. (Top) Schematic diagram of a sensor that produces an electrical output in response to the presence of an input quantity. (Bottom) Biosensor ctnn-prising the generic device shown at top with a molecular recognition layer that has a highly selective response.

These devices are conveniently small, relatively inexpensive, quite sensitive, and inherently capable of measuring a wide variety of different input quantities. It is because of these far-reaching characteristics that we have written this book in order to bring a diverse audience of readers an understanding of acoustic sensor principles. 

Volume 558— Flat-Panel Displays and Sensors—Principles, Materials and Processes, F.R. Libsch,... 

Hauptman, P. Pownall, T. Sensors principles and applications Prentice-Hall New York, NY, 1993... 

Characteristics of the Screen Printed Electrode Sensor Principle and Performance Criteria... 

CHARACTERISTICS OF THE SCREEN PRINTED ELECTRODE SENSOR PRINCIPLE AND PERFORMANCE CRITERIA... 

Grieshaber, D., MacKenzie, R., Voros, J., Reimhult, E. (2008). Electoochanical biosensors sensor principles and architectures. Sensors, 8, 1400-1458. 

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