Electronic devices sensors

The modification of electrode surfaces with electroactive polymer films provides a means to control interfacial characteristics. With such a capability, one can envisage numerous possible applications, in areas as diverse as electronic devices, sensors, electrocatalysis, energy conversion and storage, electronic displays, and reference electrode systems [1, 2]. With these applications in view, a wide variety of electroactive polymeric materials have been investigated. These include both redox polymers (by which we imply polymers with discrete redox entities distributed along the polymer spine) and conducting polymers (by which we imply polymers with delocalised charge centres on the polymer spine). 

Their unique properties predestine them for both very specific applications and broad use in the field of polymer composites. They not only enhance mechanical properties but also electrical and thermal properties, act as flame retardants, etc. Thus their positives can be successfully exploited from simple or advanced polymer matrix reinforcement, through electronic devices, sensors and actuators, to electrorheological fluids, to name just the most important applications. 

Products that result from these processes include micro-electronic devices, sensors, membranes, batteries and fuel cells, coatings and films, metals, gases, chemicals, and ceramics. 

Nanoelements have generated much interest due to their potential use in devices requiring nanoscale features such as new electronic devices, sensors, photonic crystals, advanced batteries, and many other applications. The reaUzation of commercial applications, however, depends on developing high-rate and precise assembly techniques to place these elements onto desired locations and surfaces [62],... 

Scientists have learned that the electric and optical properties of certain nanometer-size particles can be timed by adjusting the particle size or shape. Their properties are therefore of interest for applications in optical data-storage devices and ultra-fast data communications systems. Although such applications are stUl years from commercial fruition, they nevertheless offer the promise of dramatically changing not only the size of electronic devices, sensors and many other items, but also the way they are manufactured. It suggests that such devices might be assembled from simpler, smaller components such as molecules and other nanostructures. This approach is similar to the one nature uses to construct complex biological architectures. 

Synthesis of Building Blocks for Opto-electronic Devices, Sensors and Self-assembled Superstructures... 

Fig. 4. Some electronic device applications using amorphous silicon (a) solar cell, (b) thin-fiLm transistor, (c) image sensor, and (d) nuclear particle detector.

In recent years further concepts have been developed for the construction of polymer-based diodes, requiring either two conjugated polymers (PA and poly(A-methyl-pyrrole) 2 > or poly(A-methylpyrrole in a p-type silicon wafer solid-state field-effect transistor By modifying the transistor switching, these electronic devices can also be employed as pH-sensitive chemical sensors or as hydrogen or oxygen sensors 221) in aqueous solutions. Recently a PPy alcohol sensor has also been reported 222). 

It can be expected that, in the future, other organic electronic devices and circuits, such as sensors [72], radio-frequency identification tags (RFIDs) [73], and ring oscillators [74] may be fabricated using dissipative structures. 

A large number of possible applications of arrays of nanoparticles on solid surfaces is reviewed in Refs. [23,24]. They include, for example, development of new (elect-ro)catalytical systems for applications as chemical sensors, biosensors or (bio)fuel cells, preparation of optical biosensors exploiting localized plasmonic effect or surface enhanced Raman scattering, development of single electron devices and electroluminescent structures and many other applications. 

Let us start with a definition. Semiconductor chemical sensor is an electronic device designed to monitor the content of particles of a certain gas in surrounding medium. The operational principle of this device is based on transformation of the value of adsorption directly into electrical signal. This signal corresponds to amount of particles adsorbed from surrounding medium or deposited on the surface of operational element of the sensor due to heterogeneous diemical reaction. 

M. Barbara, A. Bonfiglio, L. Raffo, A. Alessandrini, P. Facci, and I. Barak, A SMOS fully integrated sensor for electronic detection of DNA hybridization. IEEE Electron Device Lett. 27, 595-597 (2006). 

A reed sensor is mounted either above or underneath the spray-arm, outside of the washing area, while a magnet is placed on the spray-arm. The reed sensor counts the revolutions of the spray-arm. If for any reason the spray-arm is not working (Dishes inside the dishwasher could block the movement, or the spray-arm is faulty, etc.), the sensor will indicate on a small outside light or display that service is needed. An additional electronic device could also be activated with this reed sensor to stop the machine, so that the dishes or the machine itself will not be damaged. 

Nearly all domestic appliances are using more and more electronics. Mechanical functions are replaced by electronic devices, mainly sensors and electromechanical actuators (such as pumps or electromotors) and microelectronic control systems. 

Thermoelectric flame failure detection Analog burner control systems Safety temperature cut-out Mechanical pressure switch Mechanic/pneumatic gas-air-ration control Thermoelectric flame supervision Thermal combustion products, discharge safety devices Electronic safety pilot Electronic burner control systems Electronic cut-out with NTC Electronic pressure sensor/transmitter Electronic gas-air-ration control with ionisation signal or 02 sensor Ionisation flame supervision Electronic combustions product discharge safety device... 

Measurements can contain any of several types of errors (1) small random errors, (2) systematic biases and drift, or (3) gross errors. Small random errors are zero-mean and are often assumed to be normally distributed (Gaussian). Systematic biases occur when measurement devices provide consistently erroneous values, either high or low. In this case, the expected value of e is not zero. Bias may arise from sources such as incorrect calibration of the measurement device, sensor degradation, damage to the electronics, and so on. The third type of measurement... 

Buried sensors are electronic devices that are designed to detect potential intruders. The sensors are buried along the perimeters of sensitive assets and are able to detect intruder activity both aboveground and belowground. Some of these systems are composed of individual, stand-alone sensor units, while other sensors consist of buried cables. 

The sensors must determine and quantify these changes and specify the nature of change and transmit or store information in a logical manner for proper countermeasures. An efficient and a reliable detector of a person wearing cologne or perfume is the nose. Can an electronic device be designed to mimic this property ... 

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