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In solar energy systems, manufacturing solar absorbers also includes an important section. A one‐perfect design is constructed in three layers to develop a good solar absorption rate and a graphene layer is used in this developed structure. Titanium (Ti) is in the base layer, Stannic selenide (SnSe2) is in the substrate layer, and Ferric Oxide (Fe2O3) is a resonator. The absorption rates can be presented between the overall wavelength range of 0.2–3 µm and divided into three segments. The absorption percentage is above 90% for 2800 nm, more than 95% is in the half region of 0.2–2 µm (1800 nm), and the perfect absorption result of 97% is between 0.2 and 1.5 µm (1300 nm), respectively. AM 1.5 section and graphene results can be calculated by using the numerical equations. To indicate the fewer and greater parameters of the present number, parameter variation sections can be presented. According to the symmetrical design of the developed structure, TE and TM results are almost identical and can be configured in color representation. The greater the amount of light intensity, the greater the number of absorption rates. The polarization can be checked between 0° and 50° changes. [ABSTRACT FROM AUTHOR]

In this study, the transfer matrix method is used to analyze the optical properties of a layered structure, {Air(SrTiO3/BSCCO)20Substrate}, consisting of air, SrTiO3, BSCCO (bismuth strontium calcium copper oxide) bilayers, and a substrate. This paper aims to investigate the transmittance spectra of two proposed one-dimensional (1D) structures, including a conventional superconductor photonic crystal (PC) and a gyroidal superconductor PC at infrared (IR) wavelengths. A comprehensive analysis has been carried out to provide useful insights into the optical properties and the behavior of the proposed structure, highlighting the impact of many parameters, such as refractive index, filling fraction, and layer thickness. The numerical findings showed that the permittivity of the BSCCO superconductor of a gyroidal geometry takes a different response compared to the conventional one. Notably, the filling fraction and refractive index of the host material have a significant control on both real and imaginary parts of the gyroidal BSCCO permittivity through the considered wavelengths. Thus, the proposed design provides high transmittivity outside the obtained photonic band gap compared to the conventional one. We believe that the designed one-dimensional gyroidal BSCCO photonic crystals could act as an efficient reflector through near IR for optoelectronics and energy applications. [ABSTRACT FROM AUTHOR]

This manuscript presents high performance dual polarized eight-element multiple input multiple output (MIMO) fifth generation (5G) smartphone antenna. The design consists of four dual-polarized microstrip diamond-ring slot antennas, positioned at corners of printed circuit board (PCB). Cheap Fr-4 dielectric with permittivity 4.3 and thickness of 1.6mm is used as substrate with overall dimension of 150 × 75 × 1.6 mm3. In mobile system due to limited space mutual coupling between nearby antenna elements is an issue that distort MIMO antenna performance. Defected ground structure is used to control coupling. The defected ground structure has advantages like ease of fabrication, compact size and high efficiency as compare to other techniques. Less than 30dB coupling is achieved for adjacent elements. The -10 dB impedance bandwidth of 700 MHz is achieved for all radiating elements ranging from 3.3 GHz to 4.1 GHz. The value is about 900MHz for -6dB. The proposed antenna offers good results in terms of fundamental antenna parameters like reflection coefficient, transmission coefficient, maximum gain, total efficiency. The antenna achieved average gain more than 3.8dBi and average radiation efficiency more than 80% for single dual polarized element. The antenna provides sufficient radiation coverage in all sides. The MIMO antenna characteristics like diversity gain (DG), envelope correlation coefficient (ECC), total active reflection coefficient (TARC) and channel capacity are calculated and found according to standards. Furthermore, effect of user on antenna performance in data-mode and talk-mode are studied. Proposed design is fabricated and tested in real time. The measured results shows that proposed design can be used in future smartphones applications. The design is compared with some of the existing work and found to be the best one in many parameters and can be used for commercial use. [ABSTRACT FROM AUTHOR]

Detecting of the levels of greenhouse gases in the air with high precision and low cost is a very urgent demand for environmental protection. Phononic crystals (PnCs) represent a novel sensor technology, particularly for high-performance sensing applications. This study has been conducted by using two PnC designs (periodic and quasi-periodic) to detect the CO2 pollution in the surrounding air through a wide range of concentrations (0–100%) and temperatures (0–180 °C). The detection process is physically dependent on the displacement of Fano resonance modes. The performance of the sensor is demonstrated for the periodic and Fibonacci quasi-periodic (S3 and S4 sequences) structures. In this regard, the numerical findings revealed that the periodic PnC provides a better performance than the quasi-periodic one with a sensitivity of 31.5 MHz, the quality factor (Q), along with a figure of merit (FOM) of 280 and 95, respectively. In addition, the temperature effects on the Fano resonance mode position were examined. The results showed a pronounced temperature sensitivity with a value of 13.4 MHz/°C through a temperature range of 0–60 °C. The transfer matrix approach has been utilized for modeling the acoustic wave propagation through each PnC design. Accordingly, the proposed sensor has the potential to be implemented in many industrial and biomedical applications as it can be used as a monitor for other greenhouse gases. [ABSTRACT FROM AUTHOR]

This study proposes a novel hybrid computational approach that integrates the artificial dragonfly algorithm (ADA) with the Hopfield neural network (HNN) to achieve an optimal representation of the Exact Boolean kSatisfiability (EBkSAT) logical rule. The primary objective is to investigate the effectiveness and robustness of the ADA algorithm in expediting the training phase of the HNN to attain an optimized EBkSAT logic representation. To assess the performance of the proposed hybrid computational model, a specific Exact Boolean kSatisfiability problem is constructed, and simulated data sets are generated. The evaluation metrics employed include the global minimum ratio (GmR), root mean square error (RMSE), mean absolute percentage error (MAPE), and network computational time (CT) for EBkSAT representation. Comparative analyses are conducted between the results obtained from the proposed model and existing models in the literature. The findings demonstrate that the proposed hybrid model, ADA-HNN-EBkSAT, surpasses existing models in terms of accuracy and computational time. This suggests that the ADA algorithm exhibits effective compatibility with the HNN for achieving an optimal representation of the EBkSAT logical rule. These outcomes carry significant implications for addressing intricate optimization problems across diverse domains, including computer science, engineering, and business. [ABSTRACT FROM AUTHOR]

Coronavirus disease (COVID-19) pandemic outbreak is being investigated by severe respirational syndrome coronavirus-2 (SARS-CoV-2) as a global health issue. It is crucial to propose sensitive and rapid coronavirus detectors. Herein, we propose a biosensor based on surface plasmon resonance (SPRE) for the detection of SARS-CoV-2 virus. To achieve improved sensitivity, a BiFeO3 layer is inserted between a metal (Ag) thin film and a graphene layer in the proposed SPRE device so that it has the structure BK7 prism/ Ag/ BiFeO3/ graphene/ analyte. It has been demonstrated that a small variation in the refractive index of the analyte can cause a considerable shift in the resonance angle caused by the remarkable dielectric properties of the BiFeO3 layer, which include a high index of refraction and low loss. The proposed device has shown an extremely high sensitivity of 293 deg/RIU by optimizing the thicknesses of Ag, BiFeO3, and the number of graphene sheets. The proposed SPRE-based sensor is encouraging for use in various sectors of biosensing because of its high sensitivity. [ABSTRACT FROM AUTHOR]

To construct photodetector and photovoltaic devices, light absorption is crucial. Herein, the absorption properties of a photonic crystal (PhC) consisting of high‐ and low‐index dielectric materials and a metamaterial defect layer are investigated. Two graphene sheets are assumed to surround the metamaterial layer. The study is theoretically investigated and numerically simulated in the gigahertz region. The metamaterial negative permittivity and permeability are assumed to follow the Drude model. The number of unit cells, graphene chemical potential (GCP), graphene phenomenological scattering rate (GPSR), and the metamaterial layer thickness are varied to examine the PhC tunable absorption properties. The following points are demonstrated: 1) the number of absorbance peaks increases as the number of unit cells increases; 2) when the GCP increases, the absorbance peaks dramatically decay; 3) the number of absorbance peaks in the absorption spectrum is independent of the GCP and GPSR; and 4) the absorbance peaks exhibit a significant enhancement with increasing GPSR. The proposed PhC can be used to design optical devices based on graphene and metamaterials, such as sensors, filters, and absorbers in the GHz range. [ABSTRACT FROM AUTHOR]

The tuning of a defect mode in a photonic crystal (PC) is of high significance for filter and sensor applications. We here investigate the tuning of the defect mode of a defective ternary PC with a semiconductor and high critical-temperature superconductor layers. A ternary photonic crystal with the heterostructure (semiconductor/superconductor/dielectric) is assumed. The transfer matrix method is employed to investigate the transmission of transverse electric waves. The refractive indices of the semiconductor and superconductor layers can be tuned by changing the operating temperature and the hydrostatic pressure. The defect mode and transmission properties can be controlled by using the hydrostatic pressure, operating temperature, frequency and thicknesses of the heterostructure layers. The analysis is performed in the frequency range of 20–65 THz. The proposed structure can be utilized as a biosensor and a narrowband transmission peaks filter. [ABSTRACT FROM AUTHOR]

This article presents a surface plasmon resonance (SPR) sensor based on a hybrid (Ag/BaTiO3/BP) structure designed to improve sensitivity and cancer prediction capabilities. A comprehensive evaluation of the sensor’s performance is conducted using transfer matrix method (TMM)-based analysis. To validate this approach, simulation has also been done using finite element method (FEM)-based COMSOL Multiphysics software. The sensor was structured for angular analysis via the attenuated total reflection (ATR) method, targeting the detection of various cancer types through refractive index (RI) changes. A shift in resonance angle was observed due to differences in the RI of normal and cancerous cells. The RI values ranged from 1.36 to 1.399 across five cell types. Sensitivities for different cancer cells were measured as 214 deg/RIU for skin (basal), 269.58 deg/RIU for cervical (HeLa), and 340.71 deg/RIU for adrenal gland (PC12). Additionally, the sensitivities were 284.29 deg/RIU for blood (Jurkat) and 412.14 deg/RIU for breast cancer cells (MDA-MB-231). Besides that, detection accuracy (DA), figure of merit (FOM), and signal-to-noise ratio (SNR) were calculated at 1.06 /°, 352.26 RIU-1, and 6.41, respectively. In addition, achieving a linear regression coefficient (R²) of 0.9685 and 2nd order polynomial coefficient (R²) of 0.9975 indicates high linearity. Overall, the sensor demonstrated greater sensitivity compared to previously reported studies. [ABSTRACT FROM AUTHOR]

The need for renewable energy is increasing as the energy demand is surging day by day. Industrial heaters can be operated using solar thermal heaters which can be used as renewable energy source. We proposed the new design of an effective solar thermal absorber with a graphene addition in three-layer constructions by using titanium (Ti) in three cylinder-shaped resonators, iron (Fe) for the substrate layer, and ferric oxide (Fe2O3) in the ground layer construction. The design is able to absorb the heat of solar and convert it to thermal energy which can be used for industrial heaters. The constructed design can evaluate the resulting absorption percentages in the four regions of ultraviolet area (UV), violet layer (V), and near and middle regions (NIR and MIR) layers effectively. The best four wavelengths (in micrometers) are also distinguished to show the distinct amount of absorption in this design such as 1.3, 1.5, 2, and 2.5, respectively. The solar absorption rate for an overall band of 2800 nm (between 0.2 and 3 µm) is 90.25% (more than 90%). Moreover, the absorption percentage explored is 96.97% (above 95%) at the 1800 nm bandwidth and 97.84% (greater than 97%) at the bandwidth range of 1000 nm, respectively. The constructed design can also be demonstrated in step by step improving solar rates, and analysis of the parameter changing can be solved. Then, the polarization section in TE and TM from the degree range 0 to 60, the electric amount in color expression, and a comparison table can also be studied in this paper. [ABSTRACT FROM AUTHOR]

Even low concentrations of pollutants in water, particularly heavy metals, can significantly affect the ecosystem and human health. Adsorption has been determined to be one of the most effective techniques of removing pollution from wastewater among the various strategies. To remove heavy metals such as Zn 2+ and Pb 2+ , we prepared a silica-coated CuMgFe 2 O 4 magnetic adsorbent using sol-gel method and tested it for wastewater treatment. X-ray diffraction investigation validated the creation of cubic spinel structure, while morphological analysis showed that silica coating reduces the particle size but boosts the surface roughness of the nanoparticles and also reduces the agglomeration between particles. UV-visible spectroscopy indicates a rise in bandgap and magnetic characteristics analysis indicates low values of magnetization due to silica coating. The kinetic and isotherm parameters for heavy metal ions adsorption onto silica-coated Cu 0.50 Mg 0.50 Fe 2 O 4 nanoparticles are calculated by applying pseudo-first-order, pseudo-second-order, Langmuir and Freundlich models. Adsorption kinetics revealed that the pseudo-second-order and Langmuir models are the best fit to explain adsorption kinetics. Synthesized adsorbent revealed 92% and 97% removal efficiencies for Zn 2+ and Pb 2+ ions, respectively., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Organic compound-based sensors are used in a variety of significant fields, including medical research, azeotropic calibration, vegetable oil extraction, the shoe industry and geothermal power plants. Here, a high-performance, two-dimensional material-based organic compound sensor has been proposed using a surface plasmon resonance (SPR) nanostructure consisting of a BK7 glass prism, Ag, BaTiO 3 , Ag, graphene and sensing layer. The reflectivity curves of the SPR device have been investigated when the sensing media are Pentane, n-Hexane, n-Heptane and n-Octane. The thickness of the BaTiO 3 layer and the number of graphene sheets have been optimized to maximize the sensitivity. The highest sensitivity attained is 220.83 deg/RIU for n-Octane with 45 nm silver/10 nm BaTiO 3 /8 nm silver and four layers of graphene. We believe that the SPR-based sensors are simple and can replace the spectrometry, chromatography and electrochemical based sensors. The proposed design is extremely effective for diverse applications in biological, industrial and chemical detection because of its simple structure and great performance., Competing Interests: The authors declare that they have no competing interests., (© 2023 The Authors.)