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Energy storage systems with non-metallic charge carriers such as ammonium-ion (NH4 +) are inherently safe and enable large-scale storage. Unlike metal ions with spherical symmetry, the intercalation of ammonium ions with a tetrahedral structure is symmetry-specific, leading to high power density and long-term cycling stability. However, developing suitable electrode materials that can reversibly host NH4 + ions to improve electrochemical performance is challenging. To address these issues, here we synthesized a sandwichstructured ammonium vanadate (NH4V4O10) and MXene (Ti3C2Tx) composite for the first time and employed it as a high-performance electrode for ammonium ion storage. Benefiting from the unique nanoarchitecture, the developed NH4V4O10/MXene electrode delivered an areal capacitance of 229 mF cm2 at a specific current of 1 mA cm-2 with -98% retention after 5000 charge--discharge cycles. Electrochemical analyses, supplemented with Raman spectroscopy and X-ray diffractometry, reveal the superior charge kinetics and structural stability of the NH4V4O10/MXene electrode under harsh operation conditions. The cell-type ammonium ion asymmetric capacitor (AIC) assembled using NH4V4O8/MXene as the positive electrode and MXene as the negative electrode delivered an energy density of 17.3 W h kg1 with excellent capacitance retention after 10 000 charge--discharge cycles. These results provide new insights for the development of safe and reliable next-generation clean energy technologies based on unconventional, nonmetal- ion-based charge storage mechanisms. [ABSTRACT FROM AUTHOR]

The present study indicates the impact of different arrangements of dielectric barrier discharge (DBD) plasma actuators on temperature field in a channel flow. The modified lumped circuit element electro-static model was used to calculate induced Lorentz body force and plasma dissipation of the actuators. Different distributions of temperature in the modeled channel flow for each arrangement of actuators (one, two, and three attached actuators) are discussed. According to the numerical simulation, DBD plasma actuators are beneficial devices for increasing temperature in the channel flow, especially near the location of the actuators that can be considered for related applications. The actuators are modeled under an incompressible flow regime with low Reynolds number of 335, and the configurations of the actuators are set to be 3 KV for the peak voltage amplitude, 10,000 Hz for the voltage frequency, and Kapton as the dielectric. [ABSTRACT FROM AUTHOR]

This study deals with an empirical investigation on the convective heat transfer of Cu/oil nanofluid flow inside a concentric annular tube with constant heat flux boundary condition and suggests a correlation to predict the Nusselt number. The average size of particles was 20 nm and the applied nanofluid was prepared by Electrical Explosion of Wire technique with no nanoparticle agglomeration during nanofluid preparation process and experiments. The nanofluid flowing between the tubes is heated by an electrical heating coil wrapped around it. The effects of different parameters such as the flow Reynolds number, tube diameter ratio, and nanofluid particle concentration on heat transfer coefficient are studied. Using the acquired experimental data, a correlation is developed for the estimation of the Nusselt number of nanofluid flow inside the annular tube. This correlation has been presented by using the exponential regression analysis and least-squares method. The correlation is valid for Cu/base oil nanofluid flow with weight concentrations of 0.12, 0.36, and 0.72 in the hydrodynamically full-developed laminar flow regime with Re <140, which is applicable in mini- and microchannel heat exchangers, and it is in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

In this study, thermo-physical properties including thermal conductivity, viscosity, density and specific heat capacity of an oil based nanofluid including silver as to be nanoparticles have been experimentally studied. The results indicate an enhancement in thermal conductivity which was depended on bulk temperature and volume fraction of utilized nanofluids. Viscosity data show a significant increment through volume fraction increasing. In addition, the specific heat capacity and density of nanofluids were studied experimentally and it was found that, all measured rheological properties of these nanofluids, were not in agreement to published correlations. [ABSTRACT FROM AUTHOR]

An oil based nanofluid including silver as to be nanoparticles was created by EEW method as a one-step method in three different volume fractions have been experimentally studied. Assessing the stability and viscosity of the nanofluids was involved in this work. The results show that the nanofluids behave in both of Newtonian and non-Newtonian in different volume concentrations. Also, an enhancement in viscosity of nanofluids has been recognized. In addition, based on the experimental results of this study and the other previous published studies on the oil based nanofluids, a correlation for predicting viscosity of oil based nanofluids has been developed and a good agreement between the experimental viscosity of applied nanofluids in this study and the predicted one has been achieved. [ABSTRACT FROM AUTHOR]