Mariya Aleksandrova
Abstract
Portable and smart electronic devices are powered by batteries whose life is limited. On the other hand, in recent years the idea of renewable energy and methods of its obtaining by environmentally friendly technologies gained popularity. The conversion of energy from various sources in the surrounding ...
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Portable and smart electronic devices are powered by batteries whose life is limited. On the other hand, in recent years the idea of renewable energy and methods of its obtaining by environmentally friendly technologies gained popularity. The conversion of energy from various sources in the surrounding environment (energy harvesting) solves the problem of battery-less power supply and satisfies the modern concepts of "clean" energy. One of the mechanisms for electrical energy generation is the piezoelectric effect, which relies on mechanical activation (vibrations, pressure, force) and the corresponding devices are piezoelectric energy harvesters. This article has overviewed the global situation, efforts, and prospects of the development of piezoelectric materials and harvesting devices in terms of research interest, industrial implementation, sectors of application and market forecasts.
Sebastian Micus; Hans-Helge Böttcher; Sibylle Schmied; Michael Haupt; Götz T. Gresser
Abstract
A drawback of the Personal Protective Equipment (PPE) providing firefighters protection under extreme conditions is their insufficient dissipation of heat and sweat. As a result the body core temperature increases to dangerous levels. At the German Institutes for Textile and Fiber Research Denkendorf ...
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A drawback of the Personal Protective Equipment (PPE) providing firefighters protection under extreme conditions is their insufficient dissipation of heat and sweat. As a result the body core temperature increases to dangerous levels. At the German Institutes for Textile and Fiber Research Denkendorf (DITF), intensive research is being conducted on cooling materials to protect firefighters from heat related deaths. For this purpose, an active water cooling textile, consisting of different layer constructions and absorption materials has been developed. The cooling mechanism is based on evaporation of the stored water in the absorption material. Two different constructions (an open and a closed system) with various nonwoven water absorption structures, which have been integrated into a textile layer structure, have been developed. We used superabsorbents polymer fleeces and natural viscos fleeces with different weights. In preparation the exact grammage and the absorptive capacity were measured. In addition we visualized the stream in the air-conveying layer. As main test method a special thermos-physiological measurement system has been used to measure the cooling ability of the different layer constructions. Moreover possible cooling effects can be calculated.
José Figueroa; Yunqi Cao; Tongyu Wang; David Torres; Nelson Sepúlveda
Abstract
The programmability of emissivity states in a monolithically integrated micro window based on vanadium dioxide (VO2) thin film is demonstrated. The 400 window features a VO2 thin film with integrated electrodes for actuation and sensing. The phase transition was induced by resistive heating, while ...
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The programmability of emissivity states in a monolithically integrated micro window based on vanadium dioxide (VO2) thin film is demonstrated. The 400 window features a VO2 thin film with integrated electrodes for actuation and sensing. The phase transition was induced by resistive heating, while the electrical resistivity and optical transmittance (for near IR wavelength of 1550 nm) of the VO2 thin film were monitored simultaneously. Abrupt drops in electrical resistance and optical transmittance confirmed the quality of the VO2 thin film. Electronic pulses were used to program emissivity states in the VO2 window. The emissivity programmed state was shown for a specific DC current over imposed with the programming pulse; but any emissivity state that belongs to the minor hysteretic curves can be obtained by choosing different electronic inputs. The fully monolithically integrated device presented here can be used for IR cloaking applications, where different emissivity values can be programmed with electronic pulses.
Tomasz Blaszczyk; John Aa. Sørensen; Per Lynggaard; Kristian Larsen
Abstract
The rapidly growing demand for even more detailed low-cost measurements of weather and environmental conditions, including wind flow, asks for self-sustained energy solutions that eliminate the need for external recharge or replacement of batteries. Today’s wind measurement market is ...
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The rapidly growing demand for even more detailed low-cost measurements of weather and environmental conditions, including wind flow, asks for self-sustained energy solutions that eliminate the need for external recharge or replacement of batteries. Today’s wind measurement market is limited to traditional anemometers, ultrasonic measurement or expensive LIDAR (Light Imaging, Detection and Ranging) systems. This paper presents the initial design considerations for a low-cost combined air speed and wind direction sensor, which harvests energy to drive it and to power the wireless transmission of system configurations and measurements. An energy-budget for this transmission is included.
Sachin B Undre; Shivani R. Pandya; Vinod Kumar; Man Singh
Abstract
Developing new smart materials and tracking their structural potential have been in focus for curing disease and other applications such as catalyzing biomolecules like proteins and selective bioremediation of toxic metals, dyes, pesticides have been thrust areas of research in the field of materials ...
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Developing new smart materials and tracking their structural potential have been in focus for curing disease and other applications such as catalyzing biomolecules like proteins and selective bioremediation of toxic metals, dyes, pesticides have been thrust areas of research in the field of materials and biomaterials sciences. Since materials are most important need of the society which develops somewhere food, drug, fuel, protective cover, defense materials, fire resistant and acoustic mechanism, UV sensitive, UV absorbing, solar radiation trapping activities. In this context, the dendrimers have been considered as ideal and smart materials to be applied for wider applications and directly, indirectly or catalyze modulator and many others. Thus, the dendrimers act as smart materials and the synthesis of such architectural and potential molecules is being considered as a new thrust area for multitasking materials with better activities to catalyze chemical and biochemical processes. The multifunctional materials of multipurpose uses with several dendrimeric branching, having innumerable binding sites and are in high demands for their drug binding, loading potential and bio coatings.
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