First-principles calculations engaging density functional theory (DFT) are employed to systematically study the optical characteristics of monolayer and bilayer boron nitride (BN) triphenylene-graphdiyne (Tp-BNyne) structures featuring varying lengths of C-chains. The thermal stability of Tp-BNyne structures at temperatures up to 1000 K is verified. The weak van der Waals interactions due to the small binding energies and significant interlayer distances maintain the cohesion between the layers.
View Article and Find Full Text PDFTheoretical and micromagnetic simulation studies of magnetic nanospheres with vortex configurations suggest that such nanostructured materials have technological advantages over conventional nanosystems for applications based on high-power-rate absorption and subsequent emission. However, full experimental evidence of magnetic vortex configurations in spheres of submicrometer size is still lacking. Here, we report the microwave irradiation fabrication of FeO nanospheres and establish their magnetic vortex configuration based on experimental results, theoretical analysis, and micromagnetic simulations.
View Article and Find Full Text PDFPolymorphic phases of copper pyrovanadate (α- and β-CuVO) were synthesized by solid state reaction and the mechanisms governing the phase transitions have been highlighted by the ThermoGravimetric Analysis (TGA) and the Differential Scanning Calorimetry (DSC). The thermal evolution of the lattice parameters was determined by high temperature X-ray Diffraction revealing negative thermal expansion coefficients. The thermogravimetric analysis coupled with differential scanning calorimetry was also used to determine the optimal conditions to obtain a dense target in order to produce thin films by the Pulsed Laser Deposition (PLD) technique.
View Article and Find Full Text PDFIn this article, the adsorption of NO ( = 1, 2) gas molecules on the (001) surface of CoFeMnSi quaternary Heusler alloys has been investigated theoretically with density functional theory (DFT) calculations. The adsorption strength was estimated with adsorption energy ( ), magnitude of charge transfer (Δ), charge density difference (CDD), minimum distance between molecule and surface (), and adsorption mechanism was analyzed with density of states. The results showed that unlike half-metallic nature of the bulk phase, the pristine CoFeMnSi(001) surface exhibited metallic character caused by the emergence of electronic states of the atoms in the top-most layer of the surface.
View Article and Find Full Text PDFAmmonia (NH) is a main environmental pollutant related to global warming, and reduction of its emission is the subject of multiple international agreements and regulations. Accordingly, the development of highly precise detectors to monitor its content in the environment is essential to track and limit its emission. This work examines the influence of modifying of armchair-graphene nanoribbon (AGNR) by zirconium (Zr) and its oxides on its adsorption for NH gas.
View Article and Find Full Text PDFBiomolecular detection methods have evolved from simple chemical processes to laboratory sensors capable of acquiring accurate measurements of various biological components. Recently, silicon nanowire field-effect transistors (SiNW-FETs) have been drawing enormous interest due to their potential in the biomolecular sensing field. SiNW-FETs exhibit capabilities such as providing real-time, label-free, highly selective, and sensitive detection.
View Article and Find Full Text PDFIEEE Trans Nanobioscience
July 2022
DNA sequencing techniques are critical in order to investigate genes' functions. Obtaining fast, accurate, and affordable DNA bases detection makes it possible to acquire personalized medicine. In this article, a semi-empirical technique is used to calculate the electron transport characteristics of the developed z-shaped graphene device to detect the DNA bases.
View Article and Find Full Text PDFComposite polymer membranes of poly(vinyl alcohol) (PVA) and iron oxide (FeO) nanoparticles were produced in this work. X-ray diffraction measurements demonstrated the formation of FeO nanoparticles of cubic structures. The nanoparticles were synthesized by a coprecipitation technique and added to PVA solutions with different concentrations.
View Article and Find Full Text PDFIn this article, a zigzag graphene nanoribbon (ZGNR)-based sensor was built utilizing the Atomistic ToolKit Virtual NanoLab (ATK-VNL), and used to detect nitric oxide (NO), nitrogen dioxide (NO), and ammonia (NH). The successful adsorption of these gases on the surface of the ZGNR was investigated using adsorption energy (E), adsorption distance (D), charge transfer (∆Q), density of states (DOS), and band structure. Among the three gases, the ZGNR showed the highest adsorption energy for NO with -0.
View Article and Find Full Text PDFAcetone is a well-known volatile organic compound that is widely used in different industrial and domestic areas. However, it can have dangerous effects on human life and health. Thus, the realization of sensitive and selective sensors for recognition of acetone is highly important.
View Article and Find Full Text PDFBiosens Bioelectron
November 2018
DNA (deoxyribonucleic acid) is the blueprint of life as it encodes all genetic information. In genetic disorder such as gene fusion, copy number variation (CNV) and single nucleotide polymorphism, DNA sequencing is used as the gold standard for successful diagnosis. Researchers have been conducting rigorous studies to achieve genome sequence at low cost while maintaining high accuracy and high throughput, as such sequencer devices have been developed which led to the evolvement of this technology.
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