Nano Research & Applications

Description

The great success of graphene has encouraged tremendous interest in searching for new two-dimensional (2D) carbon allotropes. Based on first-principles calculations, we proposed new 2D carbon allotropes obtained from the assembly of fenestrane molecule unit, named as Four-Penta-Graphenes (FPG). The fPG monolayers are energetically more favorable than pentagraphene and show excellent dynamical, thermal, and mechanical stability. They exhibit exotic mechanical properties including anisotropic in-plane stiffness and auxetic behavior with sign-tunable Poisson's ratio. Their electronic properties are diverse, ranging from narrow band gap semiconductors to metal. The electronic band gap and band edge positions of the fPG semiconductors can be flexibly modulated by strain engineering. Indirect-to-direct band gap and semiconductor-to-metal transitions can be achieved by applying compressive and tensile strains, respectively. High mobility and anisotropic effective mass of carriers make these materials promising for nanoelectronics. Using many-body GW0+BSE approximations, we reveal that the fPG semiconductors exhibit strong excitonic effects with distinct optical absorption peaks in the visible range. These remarkable optical properties make them also promising devices for optoelectronics. In the paper, innovative CNT based encoder and two priority encoders have been designed, simulated and compared with conventional CMOS encoder and priority encoders at 32 nm technology node. As the CMOS technology is continuously scaling down to physical limits of the device, several challenges come out related to scalability, reliability, short channel effects, leakage etc. To solve these issues of CMOS, CNT is one of the promising new technologies without sacrificing reliability and performance. The proposed CNT based encoder and priority encoders substantially outperformed CMOS based counterparts in Power, Delay and Power-Delay-Product. Air heaters are extensively used for various applications like space heating, drying of agricultural products etc. Air heaters are low efficient due to poor heat transfer properties of air.

Four-Penta-Graphenes

Flow obstructions enhances the heat transfer coefficient of air by disturbing the formation of the laminar sub-layer. In this work, the effect of a modified inclined delta obstruction (inclined in the direction of flow (α) and in the direction perpendicular to flow (β) on the thermal and hydraulic performance parameters of an air heater (Nusselt number-Nu, friction factor-f and Thermal Enhancement Factor-TEF). In this study initially, performance parameters of a smooth air heater (size: 30 mm × 50 mm × 300 mm, constant heat flux: 800 W/m2) are analysed using Computational Fluid Dynamics (CFD) at different air flow rates (Re = 5000,10,000,15,000 and 20,000). In the second stage, experiments are conducted on a bench-scale setup using the same conditions to validate the results obtained from CFD. Results from the CFD study were also validated by using empirical correlations (Dittus – Boelter equation and Modified Blasius equation). In third stage, the effect of orientation (α: orientation in the direction of flow, β: orientation in the direction perpendicular to flow) of the modified delta flow obstructions was studied using CFD. From the present study, it is observed that the thermo-hydraulic performance of modified delta obstruction is found to be superior to conventional delta flow obstructions. Modified delta obstructions enhance Nu by 4 to 6 times and increase pressure drop by 6 to 10 times in comparison to the air heater without obstruction. From the numerical study, it was observed that the modified delta flow obstruction improves the performance of the air heater in comparison with conventional delta obstruction and the maximum TEF of 1.99 was obtained at Re =5000, α = 300 and β = -450. Despite the fact that smart dust networks (SDNs) were in usage for more than ten years, numerous contemporary activities, including emergency management, environmental sensing, and healthcare observation, largely rely on them today. In besides having a small channel transmission rate, this form of system has a limited power capacity and a restricted existence. Because of the significant impact that communication costs have on the energy consumption of smart dust nodes, connectivity is one of these systems' greatest problems. Among the most effective methods for conserving SDN energy has indeed been demonstrated to be clustering. Among the most essential sensor network clustering protocols is LEACH (low energy adaptive clustering hierarchy). Furthermore, there are significant issues with this protocol, particularly when Cluster head (CH) is chosen randomly during setup. The purpose of this research is to improve smart dust environment by selecting a CH based on its energy consumption level. The outcomes show how effective this work is at enhancing IE2-LEACH and EESR while extending the lifespan and enhancing SDN effectiveness.

Captive Diesel Generator

As the clamour for a Net Zero carbon energy economy increases, it is necessary to harness the potential of renewable energies in powering buildings to lower fossil power plants' contributions to the overall energy mix. This paper aims to present an energy balance load sensitivity analysis and multicriteria method for sizing a green energy system for powering two office complexes that house space research laboratories. The energy component considered includes Battery Storage (BAT), captive Diesel Generator (DG), fuel cell (FC), Hydrogen Storage (H2T), solar Photovoltaic (PV), and wind turbine. Using HOMER, the techno-economic features and the hourly operational details of the energy components were obtained. The efficacy of Entropy- Additive Ratio Assessment was deployed on the outputs from HOMER to obtain the most preferred energy system based on more than one criterion. The result of the study indicates that the most preferred energy system for Abuja is a PV, WD, FC, DG, and BAT, having a total net present cost (TNPC) of $220,930.