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Funding Information: The authors acknowledge Mogorychnaya A.V. for assistance with spectroscopic experiments. The research was supported by the Russian Science Foundation , grant RSF21-72-20050 (spectroscopic measurments and analysis of carbon nanotubes films). D.S.K. and A.G.N. acknowledge Russian Foundation of Basic Research project No. 20-03-00804 (synthesis, characterization and plasma treatment of carbon nanotubes). A.P.T. acknowledges the EDUFI Fellowship (No. TM-19-11079) from the Finnish National Agency for Education and the Magnus Ehrnrooth Foundation (the Finnish Society of Sciences and Letters ) for personal financial support. Publisher Copyright: © 2021 Elsevier Ltd We investigated terahertz-infrared electrodynamic properties of wafer-scale films composed of plasma-treated single-walled carbon nanotubes (SWCNTs) and films comprising SWCNTs grown with different lengths. The spectra of complex conductance of the films were measured at frequencies 5–20 000 cm−1 and in the temperature interval 5–300 K. Terahertz spectral response of films of pristine SWCNTs is well described with the Drude conductivity model and a plasmon resonance located at ≈100 cm−1. Stepwise treatment of the films with oxygen plasma led to a gradual suppression of the Drude spectral weight from the low-frequency side. For films with the nanotubes shorter than 1 μm, i.e., close to electrons mean free path and localization length, scattering of charge carriers at the nanotubes edges is shown to additionally contribute to the carriers scattering rate and to the damping of plasmon resonance. The temperature coefficient of ac resistance (ac TCR) in both kinds of films is found to strongly increase in amplitude during cooling and frequency decrease. The values of ac TCR increase in films with longer time of plasma treatment and nanotubes with shorter length but reach saturation in films with exposure time longer than ≈100 s or composed from SWCNTs shorter than 1 μm.

An efficient approach for tailoring surface properties of polymers is presented, which enables rapid modification leading to superhydrophilic properties. The approach is based on vacuum-ultraviolet radiation (VUV) pretreatment of the surface to create reactive dangling bonds. This step is followed by a second treatment using neutral oxygen atoms that react with the dangling bonds and form functional groups. The beneficial effect of VUV pretreatment for enhanced functionalization was clearly demonstrated by comparing VUV pretreatment in plasmas created in different gases, i.e., hydrogen, nitrogen, and oxygen, which differ in the intensity of VUV/UV radiation. The emission intensity of VUV radiation for all gases was measured by vacuum ultraviolet spectroscopy. It was shown that VUV has a strong influence on the treatment time and final surface wettability. A superhydrophilic surface was obtained only if using VUV pretreatment. Furthermore, the treatment time was significantly reduced to only a second of treatment. These findings show that such an approach may be used to enhance the surface reaction efficiency for further grafting of chemical groups.

Non-thermal atmospheric pressure plasma treatment has emerged as a promising potential seed quality enhancement method over recent years. This study focuses on the effect of atmospheric pressure plasma treatment on seed germination and growth of Long Bean-KPN (Vigna unguiculata L.) seeds under laboratory conditions. In this study, the Long Bean seeds were exposed to a dry air non-thermal atmospheric pressure plasma for different periods between 4 and 10 min to study its effect on seed germination and growth behavior. It was observed that Germination percentage and Seed Vigor Index were negatively affected by plasma treatment for more than 6 min. The performance of seeds treated for 4 min had a slight improvement in germination over the control specimen, while it showed a significant improvement in average seed vigor index. The study confirmed that non-thermal atmospheric pressure plasma treatment can be stimulatory for seed germination and growth of Vigna unguiculate L. seeds if exposed to plasma for periods less than 4 min and it can be inhibitory for the purpose if exposure time exceeds 6 min.

In this work, the solution plasma-assisted method was used to prepare NiMnAl-LDO (layered double oxides) catalysts with different treatment times, which were used for the CO2 methanation reaction. Solution plasma treatment can enhance the dispersibility of the catalyst, create oxygen defects and improve the chemical adsorption capacity of the catalyst. The results show that the low-temperature activity of the catalyst has been improved after the solution plasma treatment. We demonstrate that the NiMnAl-LDO-P(20) catalyst with high dispersion has the highest catalytic activity in CO2 methanation (81.3% CO2 conversion and 96.7% CH4 selectivity at 200 °C). Even though working for 70 h, the catalyst is still highly stable. This work provides a great promise for improving the low-temperature activity of Ni-based catalysts.

Use of synthetic dyes for dyeing of textile fabrics is most problematic environmental concerned for textile industry. The demand of natural colourants for the dyeing of textile fabrics has been increasing. Thus, sustainable novel technologies for textile dyeing are needed that utilize improved colour strength and enhanced performance characteristics of the fabric. This study attempts to highlight the possibility of using cochineal natural dye in the printing of polyester fabrics after surface modification by O2/Ar plasma treatment. The colour strength, air permeability, crease recovery angle of printed fabrics, colour fastness to rubbing, washing and light, were also studied. The surfaces of untreated and plasma-treated polyester fabrics were analysed by SEM to compare the morphological changes. Surface roughness and cracks were indicated after the plasma pretreatment. The results indicated that plasma treatment could improve the printability of polyester fabric compared with untreated samples, with enhanced the adhesion and penetration of printing paste to the surface. The air permeability of printed fabrics has decreased, while the angle of crease recovery has increased. The fastness properties of printed samples were found suitable to very good.

The continuous electrolytic copper plating process traditionally includes degreasing and acid baths before copper plating baths. These baths add difficult-to-control parameters to the process. Besides they contain various alkaline chemicals and acids that are harmful to the environment. The plasma surface treatment is a controllable alternative surface cleaning method which is used in various fields. Also it can be used for surface activation to improve plating performance. Another important aspect of the plasma process is its environmental friendliness. It has a high potential to make plating preparation stages environmentally friendly and efficient. In this study a plasma surface treatment system is attached on a traditional copper plating line which is used for cold rolled low carbon steel sheets. It was determined that plasma surface treatment had a positive effect on the quality of copper plating.

In the method of nitriding elements, various methods of their thermal heating are used. The simplest heating method in ion-plasma nitriding is heating by bombarding the surface first with low-energy gas ions and then with metal ions with energies up to several kiloelectronvolt. Elements exposed to ion bombardment have a welldeveloped surface that is free from contaminants and facilitates the diffusion of nitrogen into the depth of the metal during nitriding. The paper studies the effect of various preliminary heating methods on the nitriding depth in the complex ion-plasma hardening technology of 25CrMoVA steel. A JSM 7000-1F scanning electron microscope equipped with an X-ray spectral energy dispersive microanalysis attachment was used to diagnose changes occurring on the surface of the samples and at depth; the hardness was measured using a Nanoindentor G200 device. The preliminary heating of the samples was carried out both with the use of bombardment with Ti or Mo ions, and without its direct effect on the heated surface. In the experiment, differences in the depth of hardening of the nitrided layer of steel are observed when it is heated in different ways. When bombarded with Mo ions, the greatest depths of hardening were obtained in comparison with other preliminary heating conditions. It is shown that these differences are associated with the features of the morphology of the steel surface formed as a result of sputtering processes. The formation of nitride compounds in its surface layer can serve as a barrier that slows down the penetration of nitrogen into the metal. It is shown that with complex treatment in the process of deposition of a nitride coating on the surface of nitrided steel, an additional increase in the depth of hardening of the nitrided layer occurs.

The aim of this study was to evaluate the effect of atmospheric cold plasma (ACP) on dentinal tubule penetration of EndoSequence BC. Sixty premolars were divided into four groups according to the obturation technique and plasma treatment. Root canals were filled with single cone in Group 1 (SC), single cone after ACP application in Group 2 (SC-P), warm vertical compaction in Group 3 (WVC), warm vertical compaction after ACP application in Group 4 (WVC-P). Horizontal sections were imaged using confocal laser scanning microscopy. The maximum penetration and percentage of penetration values were measured. These data were statistically analysed (P

2-D layered MoS2 is considered as a promising candidate for novel nanoelectronic devices in recent years. However, a large number of structural defects in MoS2 have been widely reported, which will greatly degrade the electrical performance of MoS2 devices. In this work, it is demonstrated that the structural defects in MoS2 can be repaired by a reasonable-power O2-plasma treatment, e.g., a 30-W O2-plasma treatment on MoS2 results in an enhanced carrier mobility of 69.82 cm2/Vs, which is 2.5 times higher than that of the untreated devices, a reduced subthreshold swing of 131.27 mV/dec, and a high ON/OFF current ratio of $3.18\times 10^{{6}}$ . These are attributed to the fact that the suitable-power O2-plasma treatment can effectively repair the structural defects in MoS2 and reduce the scattering centers, improving the electrical performance of MoS2 FETs. However, a high-power O2 plasma will generate high-energy oxygen ions to bombard the MoS2, introducing more new defects and deteriorating the electrical performance of MoS2 FETs.

This work shows the results of research of the fine and dislocation structure of the transition layer of 18CrNi3Mo low-carbon steel after the influence of electrolytic plasma. Conducted research has shown that the modified steel layer, as a result of carbonitriding, was multiphase. Quantitative estimates were made for carbonitride М23(С,N)6 in various morphological components of α-martensite and on average by material in the transition layer of nitro-cemented steel. It was established that α-phase is tempered martensite after nitrocementation. Released martensite is represented by batch, or lath and lamellar low-temperature and high-temperature martensite. Inside the tempered martensitic crystals, lamellar cementite precipitates are simultaneously present, and residual austenite is found along the boundaries of the martensitic rails and plates of low-temperature martensite. It was determined that inside the crystals of all morphological components of α-martensite there are particles of carbonitride М23(С,N)6.

A series of CoPt/ZrO2 catalysts using plasma treatment to modify ZrO2 support and/or to decompose the cobalt precusor were prepared. The nanostructure and properties of the supports and catalysts were characterized by N2-physisorption, SEM, TEM, XRD, XPS, H2-TPR and H2-TPD, and the catalytic performance of four catalysts was evaluated by Fischer-Tropsch synthesis (FTS) reaction. Characterization results showed that defects were created and morphology change was achieved on ZrO2 support by plasma modification. The synegetic effect of plasma support modification and precursor decomposition resulted in extremely high dispersion of cobalt species (∼ 1 nm), these highly dispersed cobalt particles also had improved reduction ablibity, and thus a plentiful number of active sites were generated, despite its lower TOF value, a highest apparent FT activity was presented.

In this study, we describe an atmospheric pressure plasma jet (APPJ) device made of four-bore tubing operable in inhospitable humid environments and introduce two potential applications of liquid material processing: decomposition of aqueous phosphorus compounds and solution-plasma polymerization. A four-bore tube was used as the plasma transfer conduit and two diagonal bores contained metal wires. In the proposed APPJ device, the metal wires serving as electrodes are completely enclosed inside the holes of the multi-bore glass tube. This feature allows the APPJ device to operate both safely and reliably in humid environments or even underwater. Thus, we demonstrate that the proposed electrode-embedded APPJ device can effectively decompose aqueous phosphorus compounds into their phosphate form by directly processing the solution sample. As another application of the proposed APPJ device, we also present the successful synthesis of polypyrrole nanoparticles by solution plasma polymerization in liquid pyrrole.

The role of plasma functionalization of multi-walled carbon nanotubes (MWCNTs) for room-temperature ammonia gas sensors was investigated. Plasma functionalization of MWCNTs with maleic anhydride was carried out at various durations. The active material of the gas sensor was investigated by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. It was shown that the formation of functional groups on the surface of carbon nanotubes led to an increase in the ammonia sensor response by two to four times. The increase in functionalization duration induced the rise of O/C from 0.28 to 0.335, an increase in sensor resistance, and the distortion of the shape of the I-V curves.

Biomaterials have been widely used as substitutes for diseased tissue in surgery and have gained great success and attention. At present, the biocompatibility of biomaterials such as PET woven fabrics is often evaluated both in vitro and in vivo. However, the current experimental methods cannot reveal the relationship between material surfaces and cell adhesion, and few research works have focused on the mechanisms of how the surface morphology of biomaterials affects cell adhesion and proliferation. Thus, it is meaningful to find out how the altered surfaces could affect cell adhesion and growth. In this study, we employed Ar low-temperature plasma treatment technology to create nano-grooves on the warp yarn of PET woven fabrics and seeded human umbellar vein endothelial cells (HUVEC) on these fabrics. We then assessed the O-glycan and N-glycan profiles of the cells grown on different structures of the polyester woven fabrics. The result showed that the surface morphology of polyester woven fabrics could affect the O-glycan profile but not the N-glycan profile of cultured HUVEC. Taken together, the study describes the effects of the surface morphology of biomaterial on the biosynthesis of cellular glycans and may provide new insights into the design and manufacture of biomaterials used as blood vessels based on the expression profiles of O-glycans on cultured cells.

Three different mulberry silk fabrics were modified with low temperature plasma using helium and oxygen gases. Dyeing properties of plasma treated fabrics were investigated. The dye adsorption capa...

Nine groups of knitted woolen fabrics for sportswear with different technical characteristics were treated with oxygen low-temperature plasma, and the changes in the surface morphology and chemical composition of wool fibers before and after plasma treatment, as well as the changes in the applicability indexes of knitted woolen fabrics, were studied. Finally, the comfort performance of the fabrics was evaluated by combining the concentration mapping method and the function evaluation value method. The analysis found that the surface scales of wool fibers were seriously etched after oxygen low-temperature plasma treatment, and the anti-felting, bursting strength and moisture absorption of the knitted woolen fabrics were improved. At the same time, the quick-drying index of the fabric has also been improved to a certain extent. This research provides a basis for the development of knitted woolen fabric for sportswear with excellent performance.

Carbon dioxide reforming of methane can reduce emissions of greenhouse gases, and has been extensively studied. The conventional Ni-based catalysts easily coke, sinter, and deactivate in the CRM reaction. The studies suggested that the cold plasma treatment can improve the structure of Ni-based catalysts, and so enhance coke resistance of the catalysts. The review summarized the effect of cold plasma treatment on the coke resistance of Ni-based catalysts for the CRM reaction. The main goal of the paper was to illuminate: the structure change of catalysts treated by cold plasma, such as crystal planes of Ni particles, the particles size of Ni, the Ni dispersion, the metal-support interaction, and CO2 absorption capacity; the correlation between plasma treatment conditions (treatment way and parameters) and coke resistance of the catalyst treated by cold plasma; and the mechanism of plasma treatment to improve the coke resistance of the catalysts.

This work are presented the research results of pulse plasma treatment influence on the phase composition, hardness, roughness and element composition of coatings on the bases of Fe-TiB2-CrB2. The Fe-TiB2-CrB2 coating was deposited by detonation method. The following pulse-plasma treatment was used to modify the structure and properties of the surface layers of the sprayed coating. The results of mechanical experiments showed that the hardness of Fe-TiB2-CrB2 coating increased after the treatment. On the basis of the X-ray analysis, it has been established that the increase of coating hardness is connected with phase transformations in a surface layer, in particular, with formation of oxide phases and increase of carbide particles quantity.

Mask usage has increased over the last few years due to the COVID-19 pandemic, resulting in a mask shortage. Furthermore, their prolonged use causes skin problems related to bacterial overgrowth. To overcome these problems, atmospheric pressure cold plasma was studied as an alternative technology for mask disinfection.Different microorganisms (Pseudomonas aeruginosa, Escherichia coli, Staphylococcus spp.), different gases (nitrogen, argon, and air), plasma power (90-300 W), and treatment times (45 seconds to 5 minutes) were tested.The best atmospheric pressure cold plasma treatment was the one generated by nitrogen gas at 300 W and 1.5 minutes. Testing of breathing and filtering performance and microscopic and visual analysis after one and five plasma treatment cycles, highlighted that these treatments did not affect the morphology or functional capacity of the masks.Considering the above, we strongly believe that atmospheric pressure cold plasma could be an inexpensive, eco-friendly, and sustainable mask disinfection technology enabling their reusability and solving mask shortage.

This research was targeted to investigate the effect of oxygen plasma treated graphene nanosheets (tGNSs) on the thermal stability of benzoxazine resin and to have a further and deeper mechanistic understanding of thermal decomposition kinetics of such nanocomposites in 0.5, 1 and 3 wt% of tGNS. The samples were prepared as reported in our previous study. The quality of dispersion of tGNSs within benzoxazine was investigated by X-Ray diffraction (XRD) and scanning electron microscopy (SEM) technique. Also, to ensure the complete curing of samples the differential scanning calorimetry (DSC) analysis was performed. Using thermogravimetric analysis (TGA), it was found that the addition of tGNS improved the char yield and thermal stability parameter of benzoxazine nanocomposites and this improvement was more prominent at 1% and higher amount of nanoparticles. Moreover, the first stage of thermal degradation kinetic of benzoxazine was disappeared above 1 wt% of tGNS. The samples were kinetically analyzed through Kissinger, Flynn-Wall-Ozawa and Friedman and Coats-Redfern method. It was revealed that the overall activation energy was enhanced from 168 to 224 kJ mol−1 and 275 to 420 kJ mol−1 for the second and third stage of degradation using 1 and 3 wt% of tGNS.

Atmospheric pressure cold plasma treatment on pearl millet ( Pennisetum glaucum ) with air as feed gas at an input voltage of 40 and 45 kV for 5, 10, and 15-min exposure time was studied. The influence of cold plasma on the physical, nutritional, hydration, and pasting properties of pearl millet was assessed. There was no significant difference in loose and tapped bulk density, whereas the color intensity $(\Delta E)$ and the delta chroma ( ${\Delta }C$ ) have significantly differed with the treatment. The nutritional properties, such as crude fat (3.46% ± 0.25%–4.71% ± 0.07%) were increased, whereas crude fiber (2.21% ± 0.02%–1.32% ± 0.02%), protein (10.064% ± 0.43%–8.89% ± 0.50%), and moisture (11.92% ± 0.10%–10.25% ± 0.03%) had significantly diminished. The results of hydration properties, such as swelling capacity (0.213 ± 0.003–0.320 ± 0.008 g/g), solubility (183% ± 1.00%–212% ± 2.00%), and water absorption (1.11 ± 0.02–1.51 ± 0.01 g/mL) have shown significant increment with treatment time and voltage. Besides, the pasting properties of the treated millet were significantly improved. The infrared thermal imaging was used and observed a maximum of 7 °C rise in the plasma treatment zone’s temperature throughout the treatment time. It can be concluded that the plasma treatment ameliorates hydration and pasting properties of pearl millet, paving the path for their usage in a wide range of convenient foods.

The effect of the presowing treatment of Lactuca sativa L. “Lollo Bionda” lettuce seeds with dielectric-barrier discharge plasma in air on the quality of seeds and the morphogenesis and productivity of plants grown from them has been studied. It has been found that the plasma treatment of Lactuca sativa seeds for 10 and 15 s is optimal in terms of time because the germination energy of experimental seeds increased by 11–23% relative to the reference control and laboratory germination increased by 1–2%.

This article is intended to provide a comprehensive review of the experimental studies conducted to understand the effect of several parameters involved in the discharge plasma-based nitrogen oxides (NO $_{X}$ ) removal from real diesel engine exhausts, be it stationary or automobile, in addition to simulated ones. In the last two decades, much progress has occurred in the electric discharge-based nonthermal plasma (NTP) treatment of exhaust gas with or without cascading any additional treatment technique, such as catalysts or adsorbents. Most of these studies were conducted with the aim of enhancing the removal of NO $_{X}$ or studying the efficacy of a particular parameter on NO $_{X}$ removal or both. It is now timely to collage the findings of these studies in a way to help the present researchers to understand the effect of various parameters/measures associated with stand-alone and cascaded NTP treatments for NO $_{X}$ removal. It is also intended that the current review helps in moving closer to realizing the application of NTP in the cleansing of gaseous pollutants of diesel exhaust.

This work aims at providing a simple and effective method to optimize and improve the nitrogen-based defects into intrinsically N-doped carbon-based electrospun nanofibers (CNFs) for achieving highly active catalysts for the oxygen reduction reaction (ORR). To reach this goal, plasma treatments are investigated as an effective method to tune the distribution of the N-doping sites that are vital to improve the ORR catalytic activity of the material. Morphological, physical, chemical as well as electrochemical characterizations were performed on plasma-treated CNFs to demonstrate the effectiveness of such treatments to improve the catalytic behavior of CNFs toward ORR. Finally, Microbial Fuel Cells (MFCs) were selected to test the plasma-treated nanofibers as the cathode catalyst layer demonstrating an increase of the overall performance of the MFCs with respect to the devices using the Pt-based reference catalyst.

The Purpose of paper is to conduct studies to assess the possibility of increasing the hardness of the surface layer of steel St3 grade by plasma heating of the applied surface coating containing powder alloy PR-N80X13S2R. Mixtures of pasta were divided into 2 groups: for furnace chemical-thermal treatment and plasma surface melting. The study of the microstructure showed a difference in the depth of the saturated layer, depending on the processing method, during chemical-thermal treatment-1 mm, plasma fusion - 2 mm. The results of measuring the surface micro-hardness showed that, the obtained coating from a mixture of PR-N80X13S2R + Cr2O3 + NH4Cl has a uniform high surface hardness (31-64 HRC), from a mixture of only PR-N80X13S2R - the surface hardness varies in a wide range (15-60 HRC). The study of the microhardness of the cross section of the surface layer showed that, the diffusion region: from a mixture of powder PR-N80X13S2R + Cr2O3 + NH4Cl has uniform hardness (450-490 HV); from a mixture of PR-N80X13S2R - hardness increases in the depth of the molten region (from 300 to 600 HV), and sharply decreases in the heat affected zone (210-170 HV). The use of PR-N80X13S2R alloy powder as the main component in the composition of the paste deposited on the St3 surface during plasma treatment leads to the formation of a doped surface layer with high hardness.

OBJECTIVE: In recent years many researchers applied cold plasma for wound healing. The cold plasma is irradiated on the surface of wound. In this paper the effect of irradiation of cold plasma on the skin for healing of injured tissue which is located inside body, such as tendon, is evaluated. METHODS: The male, white New Zealand, (20-week-old) were selected. Aloxan injection induced for diabetes induction and a week later the blood glucose level was measured. The standard tendon injury was created. The rabbits was divided in 3 groups. Control group, Plasma treated group at 5 kv, plasma treated group at 10 kv. Cold plasma was applied to the rabbits for 21 days. RESULTS: After 21 days the tendon tissue were considered histologically. The results show that inflammatory cells were significantly lower in the tendon treated with cold plasma at 10 kv than the others, which confirms that cold plasma treatment reduce the inflammation phase. Cold plasma treatment led to increase neovascularation and collagen production. CONCLUSION: The results of this study confirm that the cold plasma treatment of skin has positive effect on healing of tissue inside body.

The results of the analysis of various methods of refining aluminum alloys from dissolved gases and non-metallic inclusions are presented. The influence of a number of technological features of each method on the quality of the melt has been studied. Examples of equipment for the implementation of processes are presented. To analyze the effectiveness of the use of various technologies for refining aluminum alloys, their ranking was carried out. The results of the analysis are in correlation with the trends in the spread of various processes for the refining of aluminum alloys in foundries. It is shown that blowing the melt with inert gases through a rotating impeller is the most effective in terms of a set of indicators in comparison with other methods.

In this study, the research results of the influence of pulsed plasma treatment on phase composition, hardness, and roughness of Cr3C2-NiCr coatings are presented. The Cr3C2-NiCr coating was applied to substrate 12Kh18N10T stainless steel by detonation spraying method. To change the physical and mechanical properties of sprayed coating’s surface layers, subsequent pulse-plasma treatment was used. The pulse-plasma treatment leads to changing the roughness of Cr3C2-NiCr coating. The results of mechanical tests showed that after pulsed plasma treatment, the hardness of Cr3C2-NiCr coating is increased. Based on X-ray diffraction analysis, it was found that the hardness increasing of coating is associated with phase transformations on the surface layer, in particular, the formation of the oxide phase and an increase in the number of carbide particles.

The authors examined the efficiency of plasma-pulse-driven dielectric barrier discharge oxidation of a solution of methylene blue (C16H18ClN2S) and wastewater from dye-producing plants, in which the main component is 2,4-dinitrotoluene (CH3C4H3(NO2)2), as well as models of the organic component of wastewater of nuclear power plants, the main constituent of which is a phosphate (PO4 3−)-based detergent with a 26.8% surfactant content. Water films with a thickness of 0.1 mm were processed with a discharge voltage equal to 3 × 1011 V/s. The energy efficiency of water treatment was studied against the specific energy input, the frequency of the repetition of the discharge pulses and the parameters of the fluid and gas going through the discharge chamber. The highest energy output was reached at an air velocity in the discharge chamber of ∼1 cm/s, which provides a concentration of ozone (O3) of ∼1.5 mg/l. The highest energy output, the processing of 87 g of wastewater with 1 kWh, was obtained by treating an aqueous solution of methylene blue with an initial concentration of 50 mg/l at 65% decomposition. An energy consumption of 10 J is the most efficient value for treatment of the tested 10 ml wastewater samples.

Polylactic acid (PLA) and polyglycolic acid (PGA) have been widely used in the acupoint catgut embedding therapy (ACET) field. However, some defects such as hydrophobicity, poor swelling and cell adhesion properties which significantly limit their further applications. Herein, we report a strategy for developing ACET materials via 3D fabrication and plasma treatment. The results showed that modified samples showed rougher surface morphology and better hydrophilicity. Sample L4G0 (PLA strands: PGA strands=4:0) showed the largest tensile strength and elongation values at 32.15±5.26 cN/dtex and 56.37±4.38 %, respectively. Samples were proved to be non-toxicity and had better cell attachment and tissue growth ability after modification. In sum, the strategy of plasma modified PLA/PGA is deserved to be further studied with outstanding clinical efficacy.

The aims of this work were to study growth, isothiocyanate (ITC), bioactive content, antioxidant activity and anticancer activity of mustard green (MG) microgreens grown from seeds treated with cold plasma at 21 and 23 kV for 5 min. Microgreens from plasma-treated seeds at 23 kV showed almost 2-fold increased ITC content (1.57 ± 0.05 mmol/100 g DW) compared to MG from seeds without plasma (control), showed the highest total phenolic content (TPC) (6.76 ± 0.14 mg GAE/g DW) and total flavonoid content (TFC) (0.16±0.01 mg RE/g DW). However, MG plasma-treated seeds at 21 kV showed the highest antioxidant activity from 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay (3.51 ± 0.38 mg TE/g DW). Allyl isothiocyanate and 3-butenyl isothiocyanate were the dominant ITCs in MG. The highest cytotoxicities using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against MCF-7 (IC50 of 32.44 ± 1.64 μg/mL) and HepG2 (IC50 of 28.58 ± 1.04 μg/mL) after 72 h exposure were found in MG from plasma-treated seeds at 23 kV and MG from control seeds, respectively. However, MG from plasma-treated seeds at 21 kV exhibited the highest antiproliferative effect against MCF-7 (IC50 of 23.23 ± 0.23 μg/mL) and HepG2 (IC50 of 20.44 ± 0.56 μg/mL) for 14 days and also the most potent antimigratory effect. MG from cold plasma inhibited MMP-9 protein expression in both cancers indicating antimigratory property. MG from cold plasma also significantly reduced MMP-9 mRNA expression in both cancers when compared to the control and untreated cells. In conclusion, cold plasma treatment on seeds seemed to be an innovative tool to enhance ITC, TPC, TFC and anticancer properties of MG microgreens for better health implications. © 2021 Friends Science Publishers

Background Aflatoxins are one of the maximal menaces to food safety and public health and can contaminate food during the entire process from field to table, which can then be digested by the consumer, causing irreversible negative impacts such as immunotoxic, carcinogenic, and mutagenic effects. Therefore, development of novel technology to decontaminate aflatoxins is obviously important for the food industry. Cold plasma (CP) is an emerging novel nonthermal technology with eco-friendliness, high-efficiency and low cost, which has recently been widely studied for inactivating microorganisms and mycotoxins. Scope and approach This review presents a brief overview of aflatoxins and cold plasma treatment (CPT) and provides detailed information on the blocking and degradation of aflatoxins by CPT and its potential mechanisms. Furthermore, the superiority of CPT in purifying aflatoxins is highlighted by comparison with conventional methods including physical, chemical and biological treatments. Finally, the limitations and challenges of CPT are also discussed. Key findings and conclusions Recent studies show that CPT is an alternative technique to conventional methods for aflatoxins decontamination. However, the effective components and exact sites where CPT works are not completely clear, and the types of food researched are also few. Further researches should focus on breaking through these bottlenecks and provide a theoretical basis for the promotion of CPT applications.

Herein, we propose a transparent high-performance extended-gate ion-sensitive field-effect transistor (EG-ISFET) using an electrospun indium-tin-oxide (ITO) nanofiber sensing membrane with a high specific surface area. Electrospinning is a simple and effective technique for forming nanofibers. Nevertheless, one-step calcination, such as conventional thermal annealing or microwave annealing, cannot sufficiently eliminate the inherent defects of nanofibers. In this study, we efficiently removed residual polymers and internal impurities from nanofibers via a two-step calcination process involving combustion and microwave annealing. Moreover, Ar plasma treatment was performed to improve the electrical characteristics of ITO nanofibers. Conformally coated thin-film sensing membranes were prepared as a comparative group and subjected to the same calcination conditions to verify the effect of the nanofiber sensing membrane. The characteristics of the ITO nanofiber and ITO thin-film sensing membranes were evaluated using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), optical transmittance, and conductivity. Moreover, the sensor operation of the EG-ISFETs is evaluated in terms of sensitivity and non-ideal behaviors. The optimized process improves the sensor characteristics and sensing membrane quality. Therefore, the ITO nanofiber sensing membrane improves the sensitivity and stability of the EG-ISFET, suggesting its applicability as a high-performance biochemical sensor.

The cooling performance of nanoparticle (NP)-doped radiative cooling materials depends on the dispersion of the NPs in the polymer matrix. However, it is a technical challenge to suppress agglomeration of NPs due to their high surface energy, resulting in poor dispersion of the NPs in the polymer matrix. In order to optimize the dispersion of zinc oxide (ZnO) NPs in low-density polyethylene (LDPE), NPs were treated with atmospheric pressure plasmas for 30, 60 and 90 s. The ZnO NPs were dispersed in LDPE using a xylene solution method. The dispersion of the NPs was progressively improved as the plasma-treatment time increased, likely due to the roughened and perhaps also activated NP surfaces by the plasma treatment. This made the transmittances of the films decrease in the solar-radiation band and absorptivity increased monotonically in the high-energy band as the plasma-treatment time increased, while in the mid-infrared band, the films maintained a similar high transmittance to the untreated sample. The differential scanning colorimetry analysis revealed that the crystallinities of the plasma-treated NP-doped samples were similar to those of the untreated sample. The cooling-performance tests showed that the maximum temperature reductions of the films with NP plasma-treated for 0 s, 30 s, 60 s and 90 s were 6.82, 7.90, 9.34 and 10.34 °C, respectively, corresponded to the intrinsic temperature reductions of 7.27, 8.23, 10.54, and 11.40 °C, respectively, when calculated using Cui’s Model. The results of the current study show that a simple one-step atmospheric pressure plasma treatment to the ZnO NPs can indeed improve dispersion of the NPs in LDPE and lead to the greatly improved passive-cooling performance of the film.

The use of nonthermal air plasma is rapidly becoming a novel technology as an alternative source of nitrites in the meat industry. As egg white is a versatile and cost-effective ingredient commonly used to improve the texture of meat products, the effect of its addition after plasma treatment (PTEW) on the yield, pH, residual nitrite, nitrosyl hemochrome, TBARS, color, texture parameters, and aroma profile of pork liver pâtés was studied. The nitrite ion content of plasma-activated egg whites was adjusted to the positive controls containing 60 ppm (PC1) and 120 ppm (PC2) sodium nitrite by modifying the duration of their plasma treatment (PTEW1 and PTEW2, respectively). A group without the addition of nitrites was also manufactured (NC). Each treatment (NC, PC1, PC2, PTEW1, PTEW2) was analyzed on days 1, 3, 5, and 7 of storage at 4 °C. The results showed that liver pâtés containing plasma-treated egg whites had a similar nitrite and nitrosyl hemochrome content compared to samples containing the same amount of nitrite ions derived from sodium nitrite (p ≥ 0.05). In addition, 40 ppm nitrite ions, regardless of the source, was sufficient to achieve the desired reddish-pink color of the product over the entire storage period. Both nitrites from sodium nitrite and plasma-treated egg whites also significantly reduced lipid oxidation compared to the NC group (between 10% and 23% reduction on the last day), but had no significant effect on yield, pH, and texture parameters of the products. Based on the principal component analysis (PCA), the aroma profile of pâtés differed significantly between the groups with and without nitrites, with the largest differences observed on the first day (approx. 88%). Importantly, PTEW1 and PTEW2 aroma after production was similar to group PC2. The results of our study suggest that plasma-activated egg whites can be used as a potential source of nitrite in liver pâté production without adversely affecting the technological properties and shelf life of the final product.

The effect of argon (Ar) and oxygen (O2) gases as well as the treatment times on the properties of modified bamboo fibers using dielectric barrier discharge (DBD) plasma at generated power of 180 W were investigated. The plasma treatment of bamboo fibers with inert gases leads to the generation of ions and radicals on the fiber surface. Fourier transform-infrared spectroscopy (FTIR) confirmed that the functional groups of lignin and hemicellulose were reduced owing to the removal of the amorphous portion of the fibers by plasma etching. X-ray diffraction analysis (XRD) results in an increased crystallinity percentage. X-ray photoelectron spectroscopy (XPS) results showed the oxygen/carbon (O/C) atomic concentration ratio increased with increasing treatment time. The fiber weight loss percentage increased with increased treatment time. Scanning electron microscopy (SEM) images showed that partial etching of the fiber surface led to a higher surface roughness and area and that the Ar + O2 gas plasma treatment provided more surface etching than the Ar gas treatment because of the oxidation reaction of the O2 plasma. The mechanical properties of fiber-reinforced epoxy (FRE) matrix composites revealed that the F(tr)RE-Ar (30) samples showed a high tensile strength, whereas the mechanical properties of the F(tr)RE-Ar + O2 sample decreased with increased treatment time.

A silica/epoxy hydrophobic coating (water contact angel (WCA) = 130°) was prepared on a glass substrate and further treated in a low-temperature plasma (PL) condition, which surprisingly resulted i...

Cold plasma (CP) treatment for enhancing functional and cooking properties has been investigated on less rice varieties and delays the industrial adoption of this technology. This study treated three types (short-, medium-, and long-kernel) of milled rice from six Chinese varieties with helium plasma (Radio frequency, 13.56 MHz, 140 Pa) at a combination of watt and time, and evaluated the cooking properties, cooked rice texture, kernel appearance quality, and surface morphology, as well as flour thermal and thermomechanical properties. CP treatment at 120 W for 20 s significantly decreased the cooking time and the hardness of cooked rice while increasing adhesiveness, elasticity, and gruel solid loss. CP did not significantly change the appearance of milled rice, except for chalky rice rate, and kept the peak temperature and enthalpy of gelatinization in rice flour. 120W–20s CP significantly increased rice dough development and stability time, starch gelatinization maximum torque, and starch breakdown, but decreased the stability of protein network and starch retrogradation. As CP power strength increased from 120 to 520 W; the surface rupture of a rice kernel became more severe, and small particles aggregated on the rough surface. Compared with the 0 h sample of 120W–20s CP treatment, the repeating CP treatments at 24 h, 48 h, and 30 d significantly decreased water contact angle and free fatty acid content, but increased water absorption rate and chalky rice rate. These results suggest that 120W–20s helium CP improved the cooking properties of milled rice via leading to the rough kernel surface, higher water absorption rate, weak protein network, and a higher speed of starch gelatinization.

Silver nanowire (Ag NW) films are the promising next-generation flexible, transparent conductors, but their transport properties are greatly deteriorated by the insulating polyvinylpyrrolidone (PVP...

In rice (Oryza sativa L.), seeds exposed to heat stress during grain filling exhibit delayed germination because of DNA methylation levels at promoters of abscisic acid (ABA, a germination-inhibiti...

The study involves the processing of a novel poly [1, 4-phenylene-cis-benzobisoxazole] (PBO) fibre reinforced high-temperature thermoplastic composite with polyaryletherketone (PAEK) as the matrix. The PBO fibre and the PAEK film surface was modified using the method of argon and nitrogen plasma treatment. The investigation primarily focuses on evaluating the tensile properties of the fabricated laminates and correlating it with the effect of plasma treatment, surface characteristics, and its fracture surface. A 5% decrease in tensile strength was observed post argon plasma treatment while a 27% increase in strength was observed post nitrogen plasma treatment. The morphology of the failure surface was investigated by scanning electron microscopy and an interfacial failure was observed. Furthermore, the effect of plasma on the wettability of PBO fibres and PAEK film surface was confirmed by the Dynamic Contact Angle analysis and sessile drop method respectively. FTIR spectral analysis was done to investigate the effect of plasma treatment on the chemical structure on the surface. The results of the wettability study showed that the argon plasma treatment of the fibre surface increased its hydrophobicity while nitrogen plasma treatment resulted in the reduction of contact angle.

We have previously developed a poly(L-lactic) acid (PLLA) bioengineered anterior cruciate ligament (ACL) matrix that has demonstrated enhanced healing when seeded with primary ACL cells prior to implantation in a rabbit model, as compared with the matrix alone. This suggests that improving cell adhesion on the matrix may beneficially affect the healing response and long-term performance of the bioengineered ACL matrix. One regenerative engineering approach involves enhancing the surface properties of the matrix to support cell adhesion and growth in combination with point-of-care stem cell therapy. Herein, we studied the cell adhesion properties of PLLA braided microfiber matrices enhanced through the physical adsorption of fibronectin and air plasma treatment. We evaluated the kinetics and binding efficiency of fibronectin onto matrices at three time points and three fibronectin concentrations. Incubating the matrix for 120 min in a solution of 25 mg mL−1 fibronectin achieved the greatest binding efficiency to the matrix and cellular adhesion. Exposing the matrices to air plasma treatment for 5 min before fibronectin adsorption significantly enhanced the cell adhesion of rabbit bone marrow-derived mesenchymal stem cells (R-BMMSCs) 24 h post cell seeding. Finally, cellular proliferation was monitored for up to 21 d, the matrices were exposed to air plasma treatment, and fibronectin adsorption was found to result in enhanced cell number. These findings suggest that exposure to air plasma treatment and fibronectin adsorption enhances the cellular adhesion of PLLA braided microfiber matrices and may improve the clinical efficacy of the matrix in combination with point-of-care stem cell therapies.