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101.
102.
Alan Pasha Tabatabai Daniel S. Seara Joseph Tibbs Vikrant Yadav Ian Linsmeier Michael P. Murrell 《Advanced functional materials》2021,31(10):2006745
Unlike nearly all engineered materials which contain bonds that weaken under load, biological materials contain “catch” bonds which are reinforced under load. Consequently, materials, such as the cell cytoskeleton, can adapt their mechanical properties in response to their state of internal, non-equilibrium (active) stress. However, how large-scale material properties vary with the distance from equilibrium is unknown, as are the relative roles of active stress and binding kinetics in establishing this distance. Through course-grained molecular dynamics simulations, the effect of breaking of detailed balance by catch bonds on the accumulation and dissipation of energy within a model of the actomyosin cytoskeleton is explored. It is found that the extent to which detailed balance is broken uniquely determines a large-scale fluid-solid transition with characteristic time-reversal symmetries. The transition depends critically on the strength of the catch bond, suggesting that active stress is necessary but insufficient to mount an adaptive mechanical response. 相似文献
103.
Yaseen K.R. Shariff Harish K. Choudhary Vijay Khopkar Ankit Yadav R. Madhusudhana Balaram Sahoo 《Ceramics International》2021,47(10):14907-14912
We report the mechanism involved in sol-gel auto-combustion synthesis of Ba–Sr-hexaferrite (Ba1-xSrxFe12O19; x = 0, 0.25, 0.5, 0.75 and 1, BSFO) ceramic powders through the analysis of the phases evolved during annealing of the as-synthesized powders, along with their structure and morphological studies. The XRD patterns of the as-synthesized samples indicate the formation of barium/strontium monoferrite ((Ba/Sr)Fe2O4) and maghemite (γ-Fe2O3) phases along with a minute amount of hematite (α-Fe2O3) phase. Annealing of these samples facilitates formation of BSFO phase through the solid state reaction between BaFe2O4 and γ-Fe2O3 phase. Interestingly, after annealing the samples with x = 0, 0.5 and 1, at 1000 °C for 2 h, we observed that phase pure Ba–Sr hexaferrite structure forms, but for samples with x = 0.25 and 0.75, high amount of hematite (α-Fe2O3) phase is observed, especially for x = 0.75. The reason associated with this could be the large difference between the ionic radii of Ba2+ and Sr2+ ions occupying the oxygen site. Furthermore, our study on annealing dependent phase evolution confirms that, this difference in ionic radii forbids the formation of a single phase Ba–Sr hexaferrite. The growth of clear hexagonal-shaped plate-like particles with varied particle sizes was observed for all the samples. The particle size variation may be due to the influence of the ionic radii difference on the sinterability of the samples. Our study provides a better understanding of synthesis mechanism of Ba–Sr hexaferrite samples. 相似文献
104.
105.
Chandra Sekhar Yadav G. V. P. Ghali V. S. Baloji N. R. 《Russian Journal of Nondestructive Testing》2021,57(6):486-499
Russian Journal of Nondestructive Testing - Characterization of various industrial components without impairing their future utility increases the necessity of nondestructive testing (NDT)... 相似文献
106.
Wireless Personal Communications - The paper reports the performance of an energy harvesting cognitive radio network under primary user emulation (PUE) attack. A secondary user (SU) can harvest... 相似文献
107.
Devinder Yadav Yakun Yuan Venkatraman Gopalan Rishi Raj Seohyeon Jo 《Journal of the American Ceramic Society》2023,106(1):46-52
A single-crystal specimen of rutile (titania) was flashed repetitively, while increasing the electric field after each cycle. As expected, the flash onset temperature continued to drop modestly at higher fields. However, when the field was increased from 400 to 450 V cm–1, the flashed onset fell dramatically down to room temperature. We have investigated the electrical and optical properties of this room temperature flashed specimen (called SZ). The specimen was electronically conducting. Optical absorption spectroscopy revealed a narrow band of new energy levels that were generated just below the conduction band. The gap between the conduction band and this flash-induced energy level agreed with the peak in the electroluminescence spectrum. Optical second harmonic generation (SHG) is reported. The flash-on condition significantly lowered the SHG, which rebounded when the flash was turned off. This result suggests that the structure becomes more centrosymmetric in the state of flash, which may represent a disordered state of defects. The possibility of studying flash behavior at room temperature, without a furnace (as in SZ type specimens), opens a considerable simplification for in-situ characterization of flash behavior. For example, a possible relationship between memristor physics and the flash phenomenon can be studied. 相似文献
108.
Vanita Vanita Aamir Iqbal Waidha Sandeep Yadav Jörg J. Schneider Oliver Clemens 《International Journal of Applied Ceramic Technology》2023,20(1):236-250
All-solid-state lithium-ion batteries (ASSLIBs) are promising alternatives to conventional organic electrolyte-based batteries due to their higher safety and higher energy densities. Despite advantages, ASSLIBs suffer from issues like high charge transfer resistances due to the brittleness of the inorganic solid electrolyte and chemical instabilities at the lithium/electrolyte interface. Within this work, we investigate composite electrolytes (CEs) based on garnet-type Li6.4La3Zr1.4Ta0.6O12 (LLZTO), polyethylene oxide, and lithium bis(trifluoromethanesulfonyl)imide, prepared via a solvent-free cryo-milling approach in contrast to conventional solvent-mediated synthesis. Compositions ranging from polymer-rich to garnet-rich systems are investigated via X-ray diffraction, Raman spectroscopy, and Fourier transform infrared spectroscopy in order to determine the compatibility of the cryo-milling process toward membrane fabrication along with the possible chemical interactions between the composite membrane components. Electrochemical impedance spectroscopy is used to study the role of ceramic to polymer weight fraction on ionic conductivity. It is shown that the addition of succinonitrile (SCN) to the garnet-rich CEs can significantly improve the ionic conductivity compared to the SCN-free CEs. 相似文献
109.
Sidharth Kumar Sethi Rupesh Raina Shyam Bihari Bansal Anvitha Soundararajan Maninder Dhaliwal Veena Raghunathan Meenal Kalra Kritika Soni Samit Kumar Mahato Ananya Vadhera Dinesh Kumar Yadav Timothy Bunchman 《Hemodialysis international. International Symposium on Home Hemodialysis》2023,27(3):308-317
110.
Higher order elastic constants have been calculated in ZnS at 300 K and 500 K following the interaction potential model. Ultrasonic attenuation, velocity and other related parameters have been calculated using the higher order elastic constants for the different size of the material at 500 K. The size dependency of the ultrasonic properties is discussed in correlation with elastic, thermal and electrical properties. It has been found that the thermal conductivity is the main contributor to the behaviour of the ultrasonic attenuation as a function of the size and the responsible cause of attenuation is phonon-phonon interaction. The semiconducting nature of ZnS film has been achieved with the study of size variation of thermal relaxation time and ultrasonic attenuation. 相似文献