Narrow Results

This paper is devoted to investigate the cold plasma wave properties outside the event horizon of the Schwarzschild planar analogue. The dispersion relations are obtained from the corresponding Fourier analyzed equations for nonrotating and rotating, nonmagnetized and magnetized backgrounds. These dispersion relations provide complex wave numbers. The wave numbers are shown in graphs to discuss the nature and behavior of waves and the properties of plasma lying in the vicinity of the Schwarzschild event horizon.

By applying the Hamilton’s quaternion algebra, we propose the generalized electromagnetic-fluid dynamics of dyons governed by the combination of the Dirac–Maxwell, Bernoulli and Navier–Stokes equations. The generalized quaternionic hydro-electromagnetic field of dyonic cold plasma consists of electrons and magnetic monopoles in which there exist dual-mass and dual-charge species in the presence of dyons. We construct the conservation of energy and conservation of momentum equations by equating the quaternionic scalar and vector parts for generalized hydro-electromagnetic field of dyonic cold plasma. We propose the quaternionic form of conservation of energy is related to the Bernoulli-like equation while the conservation of momentum is related to Navier–Stokes-like equation for dynamics of dyonic plasma fluid. Further, the continuity equation, i.e. the conservation of electric and magnetic charges with the dynamics of hydro-electric and hydro-magnetic flow of conducting cold plasma fluid is also analyzed. The quaternionic formalism for dyonic plasma wave emphasizes that there are two types of waves propagation, namely the Langmuir-like wave propagation due to electrons, and the ’t Hooft–Polyakov-like wave propagation due to magnetic monopoles.

In this paper, we investigate the wave properties of cold plasma in the vicinity of Schawarzchild–de Sitter black hole horizon using 3 + 1 formalism. The general relativistic magnetohydrodynamical equations are formulated for this space–time with the use of Rindler coordinates. We consider both the rotating and nonrotating surroundings with magnetized and nonmagnetized plasmas. Linear perturbation and Fourier analysis techniques are applied by introducing simple harmonic waves. We derive complex dispersion relation from the determinant of Fourier analyzed equations for each case which provides real and complex values of the wave number. From the wave number we determine the phase and group velocities, the refractive index etc., which are used to discuss the characteristics of the waves around the event horizon.

Over the past decade, considerable progress has been made in the applications of TiO₂nanoparticles to get the multifunctional textiles. This paper presents the consequences of pretreatment of polyester fabric using cold plasma in the presence of oxygen — which might be beneficial for bonding nanoparticles over the polyester cotton blended curtains. Moreover, this paper presents the primary technique for suspending titanium dioxide (TiO₂) nanoparticles into nanosilica sol for nanocoating of polyester cotton blended curtains. In addition, the detailed characterization of nanocoating has been made using Field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD); and the consequences of nanocoating with and without plasma treatment for enhancing the different properties i.e. antistatic, anti UV and antibacterial property are discussed. Furthermore, the consequences of nanocoating with and without plasma treatment on the mechanical properties have also been discussed.

The hot aqueous extract of E. camaldensis leaves as a degradable agent and copper nitrate as a copper source with cold plasma was used in this work to present an easy and green technique for copper oxide nanoparticles (CuO NPs) synthesis. UV-Vis absorption spectroscopy, X-ray diffraction (XRD), Atomic Force Microscopes (AFM), and Scanning Electron Microscopes (SEM) were all used to determine the production of copper oxide nanoparticles (SEM). The energy gap was 4.9eV, and the average crystalline size of CuO NPs evaluated using the Scherrer equation was 15.06nm, according to the X-ray diffraction pattern (XRD). CuO NPs had a grain size of 70.63 nanometers, according to AFM morphology study. Finally, the effect of copper oxide nanoparticles on Gram-positive and Gram-negative bacteria, as well as fungi, was studied.

The cold atmospheric plasma in liquid (CAPL) technique was carried out in DI water as the solution to create Fe₃O₄-doped ZnO nanoparticles by adjusting the concentration (0.01, 0.02 and 0.03) M at ($V=13$kV, $I=1.66$mA and flow rate = 3L/min), while the exposure period was 3min. A UV-Vis. spectrophotometer, X-ray diffraction and field emission spectroscopy (FE-SEM) were used. The energy of the bandgap was discovered to be (2.95–2.85) eV. The form and dimensions obtained by FE-SEM have not changed much. All materials were tested against inactivated positive and negative gram bacteria (S. aureaus and E. coli) and showed promising antibacterial capabilities, especially Fe₃O₄-doped ZnO, which can inactivate bacteria under typical laboratory light.

In this paper, core–shell structured (ZnSe) is prepared bio synthesis by cold plasma technique under atmospheric pressure with an exposure time of 3min and a gas flow rate of 3L/min. Films’ structural characteristics and morphological characterization were investigated by X-ray diffractometer, atomic force microscopy (AFM) and scanning electron microscopy (FE-SEM). In addition, parameters like crystal size were calculated. Results showed XRD patterns exhibit structure of polycrystalline of preferential orientation (111) direction. SEM technique shows that the nanoparticles presented are spherical. AFM image verified film-formed spherical particles distribute uniformly. The antibacterial diffusion method property of these nanoparticles was performed against Gram-negative bacteria of Escherichia coli and Gram-positive bacteria of Staphylococcus aureus, showing good control of said bacteria. The maximum level of inhibition was found in coli form bacteria with an average inhibition zone diameter with S. aureus, implying an increasing trend with increasing/decreasing loading volume of NC volume. Therefore, these nanomaterials, which can be prepared in a simple and cost-effective way, may be suitable for new types of germicidal materials.

In recent years, plasma surface treatment has seen tremendous breakthroughs, which have revolutionized both the field of material engineering and the procedures used to modify surfaces. This paper offers a thorough discussion of the most recent discoveries and developments that have been made in the field of plasma surface treatment. It investigates cutting-edge technologies, innovative plasma sources and sophisticated process control approaches, all of which have greatly improved the effectiveness and adaptability of the therapy. The research also explores how these breakthroughs solve earlier obstacles, provide new opportunities for industrial applications and pave the way for future developments in the area. Moreover, the study looks at how these advancements open the door for future developments in the sector. This study gives useful insights into the emerging landscape of plasma surface treatment and its potential influence on a variety of sectors by summarizing and assessing current research. These insights may be found in this paper.

This research is devoted to the fabrication of zinc selenide nanostructures using the pulsed laser deposition (PLD) technique in a vacuum under a pressure of $2.5\times 10^{-2}$ mbar. The structure and structural properties were studied, as it was observed that it had polycrystalline structures and showed peaks for zinc and selenium and peaks belonging to the compound zinc selenide. As for the morphological characteristics of the nanostructures, the structures showed the nature of the surface and the roughness to identify its surface properties. Photocatalysis was carried out using several techniques (visible light, ultraviolet radiation and cold plasma), where a plasma jet system produced under normal atmospheric pressure was used in the treatment, with an exposure time of 4min and an argon gas flow rate of 3l/min. The hydrophilic properties were studied to apply these compositions in the self-cleaning process and photocatalytic activity. The results show that the ZnSe nanostructures have high wettability under UV light which has been shown to have excellent catalysis in the UV region, making its application as a self-cleaning material an attractive option.

The cold plasma technique, developed especially in recent years, opens the door to new materials with unique properties. This is related both to the plasma deposited thin films, which constitute integrally new materials, and to the plasma surface treatments, which drastically change the surface properties of conventional materials. Looking for novel solutions for innovative energy systems, it has been found that the both types of plasma activity are very useful for this purpose. The objective of this paper is to demonstrate the possibilities of the cold plasma technique for preparation of new materials for energy systems. A few examples of recent studies on such materials are presented. A special attention is focused on plasma deposited optoelectronically active thin films for solar cells, nanocatalytic thin films for fuel cells and plasma treated carbon electrodes for supercapacitors. These examples confirm the important role of the cold plasma technique in the development of modern and advanced energy systems.

This research aims to develop a novel approach, employing cold plasma technology for preparing nanoparticles of silver oxide by Anethum graveolens (dill) leaf extract as a natural reducing agent. This investigation evaluated the properties of antibacterial and antibiofilm-prepared nanoparticles. Initially, dill leaf extract was prepared to stabilize and reduce the size of silver oxide nanoparticles. Improved synthesis and optimal conditions for nanoparticle formation were achieved through the application of cold plasma technology. The results obtained showed that the prepared silver oxide nanoparticles have strong antibacterial properties and that they have antibacterial activity against a different group of bacteria that cause diseases such as Klebsiella pneumoniae (K. pneumoniae), Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The results also showed the effectiveness of nanoparticles in preventing the formation of bacterial biofilms, as the highest rate of inhibition was for gram-positive bacteria S. aureus. This study demonstrated the effectiveness of plant extracts and cold plasma technology when combined in producing nanoparticles with improved properties, which may push toward the employment of these materials in developing innovative and sustainable solutions in various scientific and applied fields.