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A comment on the paper "Diffraction of Plane Waves by an Impedance Half-plane in Cold Plasma" is presented. The continuity conditions were written in the case of the surrounding medium that was free space instead of cold plasma. [ABSTRACT FROM AUTHOR]

This paper reports the optical characterization of a controlled atmospheric-pressure dielectric barrier discharge (DBD) plasma source in air and Ar environments. In this study, Ar flow rate is held constant at 1 L/min while the operating voltages varied from 6.5 kV to 12.7 kV. Under these conditions, a calibrated commercial compact spectrometer covering the range from 200 to 850 nm was used to record the emission spectra of DBD plasma operating at different voltages, gap distances, and gas types. Using the Boltzmann distribution, we calculated the electron density ( $ n_e $ ne) and excitation temperatures in the plasma of air and Ar DBD at 2 mm gap distance . The emission spectra lines of the hydroxyl radicals (OH), $ {{N_{2}}} $ N2, and Ar ions are acquired at different operating conditions. According to the findings, the light intensity of Ar DBD is significantly higher than that of air DBD under the same conditions of operation. The intensity of the generated plasma spectrum is also shown to rise with both an increase in the input voltage and a decrease in the gap distance. The measurements also showed that the average temperature of the excited electrons is around 1.1 eV for air DBD and 0.11 eV for Ar DBD, while $ n_e $ ne for both is on the order of $ {10^{16}}\,{{\rm cm}^{-3}} $ 1016cm−3. These results show that as the working voltage increases, the plasma changes from a filamentary state to a homogeneous mode. Knowing the DBD parameters increases its chance to compete with traditional methods in many fields, such as water, polymers, and biomedical treatments. [ABSTRACT FROM AUTHOR]

Meat quality is damaged by traditional technologies. Researchers devised a revolutionary technique called plasma technology to meet the requirement for an effective cold processing method. Cold plasma (CP) used for meats and its products decontamination and storability extension has shown to be highly successful. The influence of CP on meat quality is important to its acceptability as an alternative meat processing technology. CP treatments have had effects on the color, pH, lipid oxidation, and microbial quality of different meat products. CP treatment offers crucial benefits over traditional processing methods because of its design adaptability, non-thermal behavior, relatively inexpensive, and environmental friendliness. CP processing is currently in its infancy and requires further investigation in meat and meat products to achieve its best extent. This paper discusses the fundamentals of CP technology, its effects on the quality of meats such as color, pH value, lipid oxidation, and microbial quality, and future perspectives. [ABSTRACT FROM AUTHOR]

The main objective of this paper was to illustrate the enhancement of the sensitivity of the ELISA titration of Tau proteins while reducing other non-specific adsorptions that could increase the optical densities and could lead to false positives. This goal was obtained thanks to the association of cold plasma and wet chemistries of the inner surface of the titration well. The PP surface was cold plasma-activated, then coated with different amphiphilic molecules bearing either ionic charges and/or long hydrocarbon chains. The support treated and coated with hexatrimethylammonium bromide improves the signal detection of proteins while reducing the background due to non-specific associations of biomolecules such as hyperphosphorylated Tau protein. However, coating with 3-butenylamine hydrochloride could also be suitable. [ABSTRACT FROM AUTHOR]

In this paper, cold plasma (CPTAS), formaldehyde (FTAS), and microwave radiation treated (MTAS) acorn shell obtained from Quercus petraea tree as biosorbent was characterized and its dye removal ability at different dye concentrations was studied. The isoelectric point, functional groups and morphology of acorn shell was investigated as adsorbent surface characteristics. Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and UV–Vis spectrophotometry were used. Methylene blue (MB) was used as model cationic dye. The Langmuir and Freundlich adsorption isotherm models were applied to describe the equilibrium isotherms. The results indicated that the data for adsorption of MB onto treated acorn shell fitted well with the Langmuir isotherm model. Comparison of adsorption capacities of CPTAS with FTAS has shown a significant increase by as much as about 30 mg/g (33.32%) in MB adsorption.The pseudo-first order, pseudo-second order kinetic models were examined to evaluate the kinetic data, and the rate constants were calculated. Adsorption kinetic of dyes followed pseudo-first order kinetics. Thermodynamic parameters such as free energy, enthalpy, and entropy of dye adsorption were obtained. The results indicated that acorn shell could be used as a natural biosorbent for the removal of cationic dyes. [ABSTRACT FROM PUBLISHER]

Classical stabilization techniques (thermal treatments) usually involve food to be packed after being processed. On the contrary and increasingly, novel food processing methods, such as high pressure or microwaves, imply that both packaging and foodstuff undergo the stabilization treatment. Moreover, novel treatments (UV light, irradiation, ozone, cold plasma) are specifically used for disinfection and sterilization of the packaging material itself. Therefore, in the last several years a number of papers have focused on the effects of these new treatments on food-packaging interactions with a special emphasis on chemical migration and safety concerns. New packaging materials merged on the market with specific interest regarding the environment (i.e. bio-sourced materials) or mechanical and barrier properties (i.e. nanocomposites packaging materials). It is time to evaluate the knowledge about how these in-package food technologies affect food/packaging interactions, and especially for novel biodegradable and/or active materials. This article presents the effect of high pressure treatment, microwave heating, irradiation, UV-light, ozone and, cold plasma treatment on food/packaging interactions. [ABSTRACT FROM AUTHOR]

Upon contacting with water, cold plasma should produce numerous ozone molecules and free electrons at room temperature. In this study, a cold plasma generator was used to break the walls of residual activated sludge obtained from domestic sewage. The impact was mainly influenced by the ozone generated. With 800 W power, sludge wastewater pH of 12.0, and under continuous treatment for 10 h, the system's reduction efficiency for the dry sludge was ≈90%. Furthermore, the organic matter content (especially protein) of the upper layer of the sludge solution increased a lot after the sludge digestion. This observation proved the reduction of sludge from both sides. Moreover, when the cold plasma technique was compared with thermal acid hydrolysis, thermal alkali hydrolysis, and ultrasonication for extracting protein from activated sludge, cold plasma wall-breaking sludge exhibited the highest efficiency, reaching 38.2% under ambient temperature. After the analysis, the toxic metal content in the extracted protein was near zero, which is a level other protein extraction methods via sludge breaking have not achieved to date, we attribute this efficiency to free electrons the cold plasma produce. These species promote the transformation of metal ions into atomic metals, thereby facilitating their removal. [ABSTRACT FROM AUTHOR]

Due to the advances in surface treatments, it is possible to obtain excellent cutting tools. However, the field for wood cutting tools still needs to be further investigated. In this work, titanium nitride was deposited on bandsaw blades by the cold plasma technique to increase the lifespan of the wood cutting tool, improving the coated surface. Tests were performed by varying the conditions in the amount of nitrogen and time. In addition, the industrial physical vapor deposition technique was also performed as a comparison. The morphology, structural changes and chemical mapping of the coated samples were investigated with a focus on their mechanical properties by nanoindentation and tribology tests. The surfaces were coated uniformly, with a well-adhered TiNx layer identified by X-ray diffraction and Raman spectroscopy and the electron-dispersive X-ray spectroscopy technique, it was possible to identify the presence of nitrogen in all deposited films. Although no significant differences were observed in hardness values for cold-plasma treated surfaces compared to the uncoated, their friction coefficients and wear values were lower. Physical vapor deposition coated samples had the lowest friction coefficient and wear values. In field trials, the coated cold plasma bandsaw blades had the lowest deviation when cutting the wood and show that this technique can be used for this purpose. [ABSTRACT FROM AUTHOR]

Cold plasma is one of the techniques used in recent years to improve the functionality and interfacial attributes of biopolymers. Employing cold plasma for the treatment and modification of biopolymers possesses several advantages including its biocompatibility, elimination of toxic solvents usage, treatment consistency, and appropriateness for heat-sensitive ingredients. Most studies have presented the efficacious use of cold plasma treatment in improving structural, mechanical and thermal properties of film composites. In addition, cold plasma improves the film surface characteristics, particularly in protein-based films, through bringing up the polar functional groups onto the bio-composite surface, consequently increasing roughness, improving printability, increasing adhesion, and reducing contact angle; while it is not effective in the improvement of water vapor permeability of edible films. Cold plasma-treated edible packaging films experienced significant improvement where exposed to microbial contaminations, mainly due to the non-thermal nature of cold plasma technology leading to the protection of antimicrobial potency of bioactive compounds and antimicrobial constitutes. Therefore, it can be concluded that cold plasma treatment is an innovative strategy to strengthen the edible film characteristics as a promising alternative to the currently used chemical and physical modification approaches. [ABSTRACT FROM AUTHOR]

Electrohydrodynamic (EHD) drying is a novel nonthermal technique using cold plasma in high electric field for dewatering of heat-sensitive foods. It is highly acclaimed for energy efficiency, environment-friendly nature, and low capital investments. The most important attribute of EHD drying is the minimal effect on food quality compared to thermal drying. This review provides a comprehensive overview of physicochemical, nutritional, and sensory properties of EHD-dried foods. The effect of different drying conditions, pretreatments, and combination techniques on food quality is discussed. The need for a more detailed study on the interaction between cold plasma and food is also emphasized. [ABSTRACT FROM AUTHOR]

Meat and seafood products present a viable medium for microbial propagation, which contributes to foodborne illnesses and quality losses. The development of novel and effective techniques for microbial decontamination is therefore vital to the food industry. Water presents a unique advantage for large-scale applications, which can be functionalized to inactivate microbial growth, ensuring the safety and quality of meat and seafood products. By taking into account the increased popularity of functionalized water utilization through electrolysis, ozonation and cold plasma technology, relevant literature regarding their applications in meat and seafood safety and quality are reviewed. In addition, the principles of generating functionalized water are presented, and the safety issues associated with their uses are also discussed. Functionalization of water is a promising approach for the microbiological safety and quality of meat and seafood products and possesses synergistic effects when combined with other decontamination approaches. However, functionalized water is often misused since the active antimicrobial component is applied at a much higher concentration, despite the availability of applicable regulations. Functionalized water also shows reduced antimicrobial efficiency and may produce disinfection by-products (DBPs) in the presence of organic matter, especially at a higher concentration of active microbial component. Utilization should be encouraged within regulated guidelines, especially as hurdle technology, while plasma functionalized water which emerges with great potentials should be exploited for future applications. It is hoped that this review should encourage the industry to adopt the functionalized water as an effective alternative technique for the food industry. [ABSTRACT FROM AUTHOR]

Cold plasma (CP) is a promising novel technology, which can widely be applied to accelerate the drying process and preserve the nutritional values in the foodstuff. Therefore, the aim of this study was to explore the effect of CP pretreatments on hot air drying of shiitake mushroom. Direct CP and cold plasma-activated water (CPAW) was used to treat the mushrooms before drying at 50, 60, and 70 °C. Scanning electron microscopic reports exhibited that both CP and CPAW pretreatment significantly changed the surface topography of shiitake by generating intracellular spaces, larger cavities, and less density, which in turn facilitated the drying process of shiitake. Both CP and CPAW pretreatment accelerated the mass transfer during the drying process, resulting in lower activation energy, drying time and energy requirement compared to Control. Mathematical modeling studies revealed that Page, Parabolic, Logarithmic as well as Midilli and others were the best models to adequately describe the drying kinetics of shiitake. Furthermore, CP pretreatments were better capable of preserving the phenolics, flavonoids, and antioxidant activity than Control. While CP-pretreated mushrooms preserved the highest amount of phenolics (463.30 mg/100 g), flavonoids (100.70 mg/100 g), and DPPH-relative inhibition activity (0.201). Conclusively, CP, as an effective pretreatment strategy, can repeatedly be applicable for the drying of agro-products in terms of improving the drying parameters, energy management as well as protecting the nutritional compounds. [ABSTRACT FROM AUTHOR]

Food contaminants are challenging the food industry due to the inefficiency of conventional decontamination techniques. Cold plasma as an emerging technique for the degradation of food contaminants attracted notable attention. The current study overviews the plasma-induced degradation of food contaminants, discusses the mechanisms involved, points its benefits and drawbacks out, highlights the research needed in this area, and explores future trends. According to the literature, cold plasma efficiently degraded many common pesticides (e.g. parathion, paraoxon, omethoate, dichlorvos, malathion, azoxystrobin, cyprodinil, fludioxonil, cypermethrin, and chlorpyrifos) and food allergens (e.g. tropomyosin, b-conglycinin, glycinin, trypsin inhibitor, and Kunitztype trypsin inhibitor). These degradations occurred primarily due to the presence of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the plasma that attack the chemical bonds of food contaminants. The type of pesticide degrades are highly dependent on the concentrations of plasma-generated ROS and RNS. Research showed that several parameters, such as plasma generation device, plasma exposure time, plasma power, and the carrier gas composition, influence the type and concentration of reactive species (e.g. ROS and RNS) and the overall efficiency of cold plasma degradation for a specific pesticide or allergen.HighlightsCold plasma can be used for degradation of many types of pesticides and allergens.Plasma-generated reactive species and UV can interact with pesticides and allergens.The scaled up removal of pesticides and allergens by plasma can be challenging. [ABSTRACT FROM AUTHOR]

Cold plasma has emerged as a non-thermal technology for microbial inactivation in the food industry over the last decade. Spore-forming microorganisms pose challenges for microbiological safety and for the prevention of food spoilage. Inactivation of spores induced by cold plasma has been reported by several studies. However, the exact mechanism of spore deactivation by cold plasma is poorly understood; therefore, it is difficult to control this process and to optimize cold plasma processing for efficient spore inactivation. In this review, we summarize the factors that affect the resistance of spores to cold plasma, including processing parameters, environmental elements, and spore properties. We then describe possible inactivation targets in spore cells (e.g., outer structure, DNA, and metabolic proteins) that associated with inactivation by cold plasma according to previous studies. Kinetic models of the sporicidal activity of cold plasma have also been described here. A better understanding of the interaction between spores and cold plasma is essential for the development and optimization of cold plasma technology in food the industry. [ABSTRACT FROM AUTHOR]

Interest in the development and adoption of nonthermal technologies is burgeoning within the food and bioprocess industry, the associated research community, and among the consumers. This is evident from not only the success of some innovative nonthermal technologies at industrial scale, but also from the increasing number of publications dealing with these topics, a growing demand for foods processed by nonthermal technologies and use of natural ingredients. A notable feature of the nonthermal technologies such as cold plasma, electrohydrodynamic processing, pulsed electric fields, and ultrasound is the involvement of external fields, either electric or sound. Therefore, it merits to study the fundamentals of these technologies and the associated phenomenon with a unified approach. In this review, we revisit the fundamental physical and chemical phenomena governing the selected technologies, highlight similarities, and contrasts, describe few successful applications, and finally, identify the gaps in research. [ABSTRACT FROM AUTHOR]

The inner polymeric surface of an ELISA titration well is plasma-modified and coated with different surfactant molecules. The titration of neurodegenerative proteins markers (prion. Tau and α-synuclein), previously demonstrated as more efficient with such modified tubes, is related to the adhesion behaviour of these proteins and their corresponding capture antibodies. The adhesion process is studied in terms of anchoring and specific mechanisms. The proteins and antibodies binding onto such modified surfaces is related to the substrate hydrophilic character calculated from the angle contact measure, to the polymer surface charge measured through the streaming potential determination at different pH and the inner surface roughness determined from AFM images. Furthermore, the influence of the blocking agent used during the ELISA titration is also studied. [ABSTRACT FROM AUTHOR]

2024 aluminium alloy is commonly used for the fuselage of aircraft or helicopters because of its high strength. The fuselage bears the weight of the movers of the aircraft and the oil or petrol tanks. It works where the climatic conditions are very harsh, i.e. very low temperature and salt fog, and in presence of aggressive chemical agents. The aluminium fuselage needs to be protected from water, heat and aggressive chemical agents, such as hydrocarbons, lubricating oils or salt fog, by a paint coating. It is important that the adhesion between the paint and the aluminium alloy remains strong for a long time. A complex and critical process is industrially used to enhance both wettability and adhesion of paint to the aluminium alloy. Cold plasma represents an efficient, non-polluting and economical alternative to clean and activate aluminium surfaces. The present work describes the possibility to use an aluminium alloy, pre-treated by cold plasma and then protected by a paint coating, in the presence of water or high temperature, as well as aggressive environmental conditions. Adhesion between the paint and the aluminium surface was characterized by a set of mechanical and physical-chemical tests. Many experimental tests were carried out in order to understand the interaction between plasma and workpiece material. The results obtained by the cold plasma treatment and the commonly used industrial process have been compared. Also, the nature of the relationship between wettability and adhesion was investigated. The results show that cold plasma allows to eliminate cleaning by a solvent and to reduce the quantity of Alodine 1200® or XPD® primer applied and, therefore, to reduce the use of polluting substances and the weight of the whole helicopter or aircraft. [ABSTRACT FROM AUTHOR]