Active control of strain in a composite plate using shape memory alloy actuators     

Ermira J. Abdullah  Dayang L. Majid  Fairuz I. Romli  Priyanka S. Gaikwad  Lim G. Yuan  Nurul F. Harun 《International Journal of Mechanics and Materials in Design》2015,11(1):25-39

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Chanhyuk Choi;Junghyun Lee;Shuvaraj Ghosh;Malkeshkumar Patel;Junsik Lee;Priyanka Bhatnagar;Naveen Kumar;Chidingozi Emeka Osigwe;Joondong Kim; 《Solar RRL》2024,8(4):2300936

Is it possible to achieve efficient energy control without it being visible? If it could, it would enable human to produce energy in a transparent manner and manage energy usage intelligently by reducing consumption through building and vehicle windows, and other structures. Herein, thin films are created that are highly transparent and can filter light by selecting specific wavelengths. The films consist of multiple layers of ITO/Ag/ITO/Ag/ITO (IAIAI) that are designed to reflect light selectively using the Bragg reflection effect. These films are able to block an average of 89.6% of near-infrared light in the 800–1400 nm range, while maintaining a high optical transparency of 69.2% (±0.1%) at 550 nm with an excellent sheet resistance value of 1.06 Ω □−1. The IAIAI structure is also used as electrodes for transparent photovoltaic (TPV) devices, allowing for the collection of photogenerated carriers while ensuring overall optical transparency. ZnO/NiO-based TPV devices using IAIAI films as transparent conducting electrodes are found to have a high open-circuit voltage value of 271 mV with a short-circuit current density value of 1.55 mA cm−2. Thus, the multifunctional IAIAI films offer a range of possibilities for transparent energy devices.  相似文献   

    

Priyanka Rade;Shubhangi Swami;Varsha Pawane;Ranjit Hawaldar;Vijaya Giramkar;Shany Joseph;Bharat Kale; 《Polymer Engineering and Science》2024,64(5):2202-2213

Digital light processing (DLP) based three-dimensional (3D) printing technology which uses photocurable resin has been a center of interest due to its printing accuracy and printing speed. In our research, we have synthesized and modified the bisphenol A-based epoxy acrylate resin for the DLP 3D printer having a printing accuracy of 50 μm. As the viscosity plays an important role in printing accuracy, the resin was modified with mono-functional, di-functional, tri-functional, and combination of di-tri functional acrylate diluents as well as with photoinitiator to achieve the desired level of viscosity. The process parameters like curing time and intensity were optimized using the DLP 3D printer. The uncured and UV-cured samples were characterized using FTIR-ATR, 1HNMR, UV–VISIBLE, and TGA techniques. The analysis of the uncured and UV-cured samples was carried out using viscosity, gel content, water absorption, and chemical resistance test. The mechanical properties of the UV-cured samples were determined using hardness and tensile strength test. The 3D-printed samples were observed under high-resolution microscope to confirm the printing quality and resolution. The resulting outcome confirmed that the proper selection of diluents is an important parameter for achieving the good quality and resolution of samples printed using the DLP 3D printer technology.  相似文献   

    

Priyanka Yadav;Sudhir G. Warkar;Anil Kumar; 《Polymer Engineering and Science》2024,64(10):4816-4833

The present study describes the facile synthesis of graphene oxide (GO) and GO/carboxymethyl tamarind kernel gum (CMTKG)-based hydrogel composite. The synthesized GO/CMTKG/PAM hydrogel composite was applied as an adsorbent for the selective sequestration of toxic crystal violet (CV) and methylene blue (MB) from an aqueous medium. The impact of various controlling parameters such as contact time, pH, concentration, adsorbent dosage, and temperature was studied. The experimental data obtained from the isotherm and kinetics modeling showed a good correlation with the Langmuir isotherm and pseudo-second-order kinetics model, respectively. The optimized concentration of dye was 40 mg L−1 for CV and 20 mg L−1 for MB, and the adsorption capacity (qmax) was calculated to be 111 mg g−1 for CV dye and 25 mg g−1 for MB dye. The synthesized adsorbent exhibits excellent recyclability for dye uptake after six consecutive cycles. Furthermore, the simultaneous adsorption of CV and MB from the binary system was carried out to ascertain the utility of the adsorbent in a wide range of adsorption systems. The adsorbent was also found to act as a proficient adsorbent in various water samples. These results demonstrated that synthesized hydrogel can be successfully applied as an adsorbent for the sequestration of dye effluents in real-time applications.  相似文献   

    

Priyanka Sharan  Abdallah Daddi-Moussa-Ider  Jaime Agudo-Canalejo  Ramin Golestanian  Juliane Simmchen 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(36):2300817

Due to the intrinsically complex non-equilibrium behavior of the constituents of active matter systems, a comprehensive understanding of their collective properties is a challenge that requires systematic bottom–up characterization of the individual components and their interactions. For self-propelled particles, intrinsic complexity stems from the fact that the polar nature of the colloids necessitates that the interactions depend on positions and orientations of the particles, leading to a 2d − 1 dimensional configuration space for each particle, in d dimensions. Moreover, the interactions between such non-equilibrium colloids are generically non-reciprocal, which makes the characterization even more complex. Therefore, derivation of generic rules that enable us to predict the outcomes of individual encounters as well as the ensuing collective behavior will be an important step forward. While significant advances have been made on the theoretical front, such systematic experimental characterizations using simple artificial systems with measurable parameters are scarce. Here, two different contrasting types of colloidal microswimmers are studied, which move in opposite directions and show distinctly different interactions. To facilitate the extraction of parameters, an experimental platform is introduced in which these parameters are confined on a 1D track. Furthermore, a theoretical model for interparticle interactions near a substrate is developed, including both phoretic and hydrodynamic effects, which reproduces their behavior. For subsequent validation, the degrees of freedom are increased to 2D motion and resulting trajectories are predicted, finding remarkable agreement. These results may prove useful in characterizing the overall alignment behavior of interacting self-propelling active swimmer and may find direct applications in guiding the design of active-matter systems involving phoretic and hydrodynamic interactions.  相似文献   

    

Priyanka B.N.  Jayaparvathy R 《International Journal of Communication Systems》2023,36(15):e5561

A wireless body area network (WBAN) enables the continuous monitoring of health conditions including heart rate, temperature, and glucose levels. It is composed of several sensors that are placed on the body. The network's performance is significantly affected by the unpredictable movements of the human body. Due to the varying proximities between them, the existence of several WBANs creates a challenge when mobility is involved. In this fictitious scenario, we consider a park area with both mobile and static WBANs or WBAN-equipped individuals passing through the park who have varying degrees of mobility. When a mobile WBAN passes a static WBAN and is within a minimum distance of the static WBAN, they pair up and immediately interfere. Inter-interference caused by WBANs operating in a limited area causes packet loss and performance deterioration. In this work, static WBAN locations are optimised to minimise interference and system inter-interference problems are addressed by a game theoretic method. This paper formulates a flexible game theoretic framework to study WBAN coexistence using the expected pay-off function considering a two-player game. It is observed from the results obtained that the probability of interference caused by fast mobile WBANs is reduced to a maximum of 50% compared with that caused by slow mobile WBANs thereby reducing the need for relocation of static WBANs.  相似文献   

    

Bhrigu K. Kalita  Rita Choudhury 《亚洲传热研究》2023,52(2):2117-2136

The quintessence of this article encompasses the effect of diffusiophoresis, chemical reaction, and varying viscosity as well as thermal conductivity on a fully developed dissipative flow through an upright channel. The fluid is electrically conducting undergoing mixed convection. The governing equations, after transfiguring into dimensionless formation, are solved through a numerical procedure for boundary value problems incorporating MATLAB solver. Imperative scrutiny is made to visualize associative impacts of flow parameters, namely, magnetic parameter, the Brinkmann number, the Schmidt number, variable viscosity parameter, variable thermal conductivity parameter, chemical reaction parameter, diffusiophoretic parameter, and particle diffusion parameter, on the flow. The velocity field, the temperature field, the solute concentration field, the particle concentration field, the skin friction, the Nusselt number, the Sherwood number, and the particle concentration gradient are assessed in view of alteration of the aforesaid parameters with the help of visual illustrations in graphical form and tabular form. Solute mass transposition and colloidal particle locomotion are the fresh inclusions to the scrutiny of upright channel flow in light of solving scheme of bvp4c. Chemical reaction engulfs both solute and particle concentration. Growing viscosity hinders the fluid velocity and heats up the flow encouraging interlayer friction.  相似文献   

    

Priyanka Das  Kaushik Mandal 《International Journal of Numerical Modelling》2023,36(1):e3027

In this article, novel designs of two different types of graphene-based absorbers of arbitrary geometry have been investigated. The first absorber uses a graphene sheet and an array of metallic patches on silicon substrate for dual-band absorption without the application of chemical potential. The second absorber is formed of a combination of graphene and metallic patches on the same substrate and is tunable over the frequency range 6.2–6.6 THz. Tunability is employed by electrostatic biasing of graphene patches from 0.4 to 1 eV. Using only a single layer of patterned graphene patches of two different sizes loaded around a square-shaped metallic patch on SiO₂ substrate, an absorption bandwidth of 500 GHz is exhibited. The proposed absorbers are analyzed rigorously by an equivalent circuit model (ECM). The validation of ECM analysis is done through full-wave simulations in CST 2021.  相似文献   

    

Kangkana Kalita;Binglin Zeng;Jae Bem You;Yifan Li;Anotidaishe Moyo;Ben Bin Xu;Xuehua Zhang; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(33):2400849

Liquid organic hydrogen carrier is a promising option for the transport and storage of hydrogen as a clean energy source. This study examines the stability and behavior of organic drops immobilized on a substrate during an interfacial hydrogen-evolution reaction (HER) at the drop surface and its surrounding aqueous solution. Hydrogen microbubbles form within the drop and rise to the drop apex. The growth rate of the hydrogen in-drop bubble increases with the concentration of the reactant in the surrounding medium. The drop remains stable till the buoyancy acting on the in-drop bubble is large enough to overcome the capillary force and the external viscous drag. The bubble spontaneously rises and carries a portion drop liquid to the solution surface. These spontaneous rising in-drop bubbles are detected in measurements using a high-precision sensor placed on the upper surface of the aqueous solution, reversing the settling phase from phase separation in the reactive emulsion. The finding from this work provides new insights into the behaviors of drops and bubbles in many interfacial gas evolution reactions in clean technologies.  相似文献   

    

Kamlendra Vikram  Uvaraja Ragavendran  Kanak Kalita  Ranjan Kumar Ghadai  Xiao-Zhi Gao 《计算机、材料和连续体（英文）》2021,66(2):1771-1784

In this work, diamond-like carbon (DLC) thin film coatings are deposited on silicon substrates by using plasma-enhanced chemical vapour deposition (PECVD) technique. By varying the hydrogen (H₂) flow rate, CH₄−Argon (Ar) flow rate and deposition temperature (T_d) as per a Box-Behnken experimental design (BBD), 15 DLC deposition experiments are carried out. The Young’s modulus (E) and the coefficient of friction (COF) for the DLCs are measured. By using a second-order polynomial regression approach, two metamodels are built for E and COF, that establish them as functions of H₂ flow rate, CH₄-Ar flow rate and T_d. A non-dominated sorting genetic algorithm (NSGA-III) is used to obtain a set of Pareto solutions for the multi-objective optimization of E maximization and COF minimization. According to various practical scenarios, evaluation based on distance from average solution (EDAS) approach is used to identify the most feasible solutions out of the Pareto solution set. Confirmation experiments are conducted which shows the efficacy of the polynomial regression—NSGA-III—EDAS hybrid approach. The surface morphology of the DLCs deposited as per the optimal predictions is also studied by using atomic force microscopy.  相似文献