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51.
A vibration isolator with energy harvesting abilities is presented in this work. The developed device is able to isolate the environment from vibration of appliances, such as household electrical generators, domestic refrigerators, microwave oven, and automobile's engine, and at the same time convert the vibration to electrical energy. The resulting energy produced by the device can be utilized to operate the wireless condition monitoring units. The developed device composed of piezoelectric disc embedded in silicone rubber and is able to exhibit a resonance at 56‐Hz frequency. When subjected to a sinusoidal force, an open circuit voltage of 1.7 V is generated by the devised harvester. Furthermore, the device generated an optimum power of 2.12 mW at a matching load of 340 kΩ and frequency (resonant) of 56 Hz. However, while operating in the isolation region, it is capable of producing a load voltage of 0.87 and 0.25 V and power of 1.8 and 0.51 mW at 1.4 and 3.5 frequency ratios, respectively. 相似文献
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Wireless Networks - Wireless sensor network (WSN) consists of small sized devices containing different sensors to monitor physical, environmental and medical conditions during surveillance of... 相似文献
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Water Resources Management - A rainfall forecasting method based on coupling wavelet analysis and a novel artificial neural network technique called extreme learning machine (ELM) is proposed. In... 相似文献
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A method is described for the estimation of individual polyphenols of tea leaf. Polyphenols separated by two-way paper chromatography of a methanolic extract of the material were located under ultra-violet light. The excised spots were eluted with water and estimated from extinctions at 275 nm. Three of the polyphenols, (?)-epigallocatechin gallate, (?)-epigallocatechin and (?)-epicatechin gallate, which comprise 10-19% of the dry matter of tea shoots from Assam, are partly consumed during the manufacture of black tea. Seasonal variation in the polyphenolic content of some jats and clones grown in North East India are described. The phenolic content of the tea shoots was higher during rains. Changes in the phenolic pattern during the growth and development of tea flower, fruit and seed are described. Organs of tea, such as sepals, petals and pericarp with closer morphological affinities to the leaf, showed a greater degree of similarity in their phenolic pattern compared with other organs such as stigma, style, carpel, anther and testa. The gallates were mostly confined to the chlorophyll-bearing organs. 相似文献
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Sr2La3Nb1?x Ta x Ti4O17 (0 ≤ x ≤ 1) ceramics were processed via a solid-state mixed oxide route. Sr2La3Nb1?x Ta x Ti4O17 (0 ≤ x ≤ 1) solid solutions were single phase in the whole range of x values within the x-ray diffraction (XRD) detection limit. The microstructure comprised elongated and needle-shaped grains. The ceramics exhibit relative permittivity (ε r) of 73 to 68.6, product of unloaded quality factor and resonant frequency (Q u f 0) of 7100 GHz to 9500 GHz, and temperature coefficient of resonant frequency (τ f) of 78.6 ppm/°C to 56.6 ppm/°C. 相似文献
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Khan Afrasyab Sanaullah Khairuddin Spiridonov E. K. Podzerko A. V. Khabarova D. F. Ali Ahmad Hasan Farooqi Ahmad Salam Zwawi Mohammed Algarni Mohammed Felemban Bassem F. Bahadar Ali Ullah Atta Abdullah Bawadi 《Instruments and Experimental Techniques》2021,64(5):785-785
Instruments and Experimental Techniques - An Erratum to this paper has been published: https://doi.org/10.1134/S0020441221050249 相似文献