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31.
Iftikhar Ahmad M. Mohib Ur Rehman Masroor Khan Ahmad Abbas Sarmad Ishfaq Sohail Malik 《国际能源研究杂志》2019,43(10):5384-5391
Battery is the sole power source for Internet of thing (IoT) sensors. Due to limited shelf life, the batteries are required to be replaced intermittently. This periodic replacement of batteries is inflated in terms of both logistics and time. This article illustrates conceptual design, development, and characterization of a flow‐based electromagnetic‐type energy harvester (F‐EH) using microplanar coil for IoT sensors application. The F‐EH converts hydro energy into useful electrical energy utilizing electromagnetic transduction mechanism. The microfabrication and macrofabrication techniques adopted to manufacture harvester's components are presented. The F‐EH has been successfully characterized by laboratory scale experimental flow test loop commissioned for this work. Experimentation with associated uncertainty analysis prevails that at a matching impedance, the F‐EH can generate a 686 μW of maximum power at an operating flow rate of 12 L/min with an uncertainty of 8.1%. 相似文献
32.
Saeed Ur Rehman Ahmad Shaur Hye-Sung Kim Dong Woo Joh Rak-Hyun Song Tak-Hyoung Lim Jong-Eun Hong Seok-Joo Park Seung-Bok Lee 《International Journal of Applied Ceramic Technology》2021,18(2):511-524
A dense Ce0.9Gd0.1O2−d (GDC) interlayer is an essential component of the SOFCs to inhibit interfacial elemental diffusion between zirconia-based electrolytes (eg YSZ) and cathodes. However, the characteristic high sintering temperature of GDC (>1400°C) makes it challenging to fabricate an effective highly dense interlayer owing to the formation of more resistive (Zr,Ce)O2 interfacial solid solutions with YSZ at those temperatures. To fabricate a useful GDC interlayer, we studied the influence of transition metal (TM) (Co, Cu, Fe, Mn, & Zn) doping on the sintering and electrochemical properties of GDC. Dilatometry data showed dramatic drops in the necking and final sintering temperatures for the TM-doped GDCs, improving the densification of the GDC in the order of Fe > Co > Mn > Cu > Zn. However, the electrochemical impedance data showed that among various transition metal dopants, Mn doping resulted in the best electrochemical properties. Anode supported SOFCs with Mn-doped, nano, and commercial-micron GDC interlayers were compared with regard to their performance and stability levels. Although all of the SOFCs showed stable performance, the SOFC with the Mn-doped GDC interlayer showed the highest power density of 1.14 W cm−2 at 750°C. Hence, Mn-doped GDC is suggested for application as an effective diffusion barrier layer in SOFCs. 相似文献
33.
Zhong Minglong Xie Weicheng Rehman Sajjad Ur 《Journal of Superconductivity and Novel Magnetism》2022,35(5):1329-1335
Journal of Superconductivity and Novel Magnetism - Microstructure optimization is highly desirable for improving the magnetic properties of permanent magnetic materials. To optimize the... 相似文献
34.
Raja Aqib Sarang Kiani Shaher Bano Abdul Wadood Muhammad Atiq Ur Rehman 《International Journal of Applied Ceramic Technology》2021,18(3):544-562
In this study, we investigated surface and biological properties of Ag–Sr-doped mesoporous bioactive glass nanoparticle (Ag–Sr MBGN) loaded chitosan/gelatin coatings deposited by electrophoretic deposition (EPD) on 316L stainless steel. The EPD parameters, that is, deposition time, applied voltage, and distance between the electrodes was optimized by the Taguchi design of experiment (DoE) approach. Scanning electron microscopy (SEM) images illustrated the spherical morphology of the synthesized Ag–Sr MBGNs with the mean particle size of 160 ± 20 nm. Energy-dispersive X-ray (EDX) spectroscopy results confirmed the presence of Ag and Sr in the synthesized MBGNs. Optimum EPD parameters determined by DoE approach were 5 g/L of Ag–Sr MBGNs, deposition time of 5 min, and applied voltage of 30 V. SEM images confirmed that the coatings were fairly homogenous. Fourier-transform infrared spectroscopy and EDX results confirmed the presence of chitosan, gelatin, and Ag–Sr MBGNs in the coatings. Chitosan/gelatin/Ag–Sr MBGN composite coatings exhibited suitable wettability for the protein attachment and proliferation of osteoblast cells. The composite coatings exhibited suitable adhesion strength with the substrate. The coatings developed HA crystals upon immersion in simulated body fluid. The results of the turbidity test confirmed that the coatings are antibacterial to the Escherichia coli cells. 相似文献
35.
Kwan-Ho Park Sin-Wook You Soon-Chul Ur Il-Ho Kim Soon-Mok Choi Won-Seon Seo 《Journal of Electronic Materials》2012,41(6):1051-1056
The thermal stability of skutterudite-based thermoelectric modules is of great importance since they are used at elevated temperatures. This study examined the high-temperature stability of In-filled and Fe-doped skutterudites (In0.25Co3FeSb12) as a function of the following aging variables: atmosphere (vacuum and air), temperature, and time. Sb-based oxides are produced preferentially on exposure to high temperatures in air. The oxide layer produced during aging at 823?K in air was much thinner than that produced during aging at 723?K in air. The formation of InSb is believed to retard the oxidation of Sb and act as an obstacle to the growth of the oxide layer. The CoSb3-based skutterudites were stable at 823?K if they were not exposed to air, and InSb phases were not produced in the In0.25Co3FeSb12 skutterudites. 相似文献
36.
Intermittent drying may be of interest in the future to address energy issues. Such drying conditions are also likely to help stress relaxation through mechanosorptive creep. The influence of applying oscillations of temperature and relative humidity during the drying of beech timber on time and drying stresses is discussed in the paper by means of nonsymmetrical and loaded drying. Experimental data were used to validate a numerical model in the case of intermittent drying. The model was then used to perform a numerical investigation of the possibility of using an intermittent energy source to dry wood. 相似文献
37.
Multimedia Tools and Applications - Performances of speech enhancement algorithms depend greatly on the accuracy of the estimated noise. In this paper, we explain in details the relationship... 相似文献
38.
This study offers new insights into two-lift deposition of mature fine tailings under atmospheric drying. The interaction of newly added lift and former lift(s) was evaluated using column experiments in terms of volumetric water content, electrical conductivity (EC), hydraulic conductivity, geochemistry and microstructure. Water content and EC followed the same trend and decreasing of water content appears to be responsible for significant reduction in EC. Evaporation on top of the column reduced the water content to almost zero. The obtained results support the coupling between the hydraulic and chemical processes that should be considered by active operators. 相似文献
39.
Senggam Wakhet S. S. Sagiri S. S. Ray Arfat Anis 《Polymer-Plastics Technology and Engineering》2016,55(5):530-541
The present study describes the encapsulation of vegetable fats (cocoa butter and mango butter) within chitosan microparticles by double emulsion technique to prevent leaching of the internal apolar phase. Leaching studies suggested negligible leaching of the internal phase (~12–14%) when the fats were encapsulated as compared to the control (~40%). Fourier transform infrared spectroscopy and differential scanning calorimeter studies confirmed the successful encapsulation of fats. The release of drug (ciprofloxacin) from the microparticles was diffusion and erosion mediated and were capable to elicit antimicrobial activity against Escherichia coli. The study suggests that the developed microparticles have the potential for controlled delivery of antimicrobials. 相似文献
40.