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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.

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.

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.

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.

Microalgae have shown great potential as a source of biofuels, food, and other bioproducts. More recently, microfluidic devices have been employed in microalgae‐related studies. However, at small fluid volumes, the options for controlling flow conditions are more limited and mixing becomes largely reliant on diffusion. In this study, we fabricated magnetic artificial cilia (MAC) and implemented them in millimeter scale culture wells and conducted growth experiments with Scenedesmus subspicatus while actuating the MAC in a rotating magnetic field to create flow and mixing. In addition, surface of MAC was made hydrophilic using plasma treatment and its effect on growth was compared with untreated, hydrophobic MAC. The experiments showed that the growth was enhanced by ten and two times with hydrophobic and hydrophilic MAC, respectively, compared with control groups which contain no MAC. This technique can be used to investigate mixing and flow in small sample volumes, and the enhancement in growth can be beneficial for the throughput of screening studies. Moreover, the methods used for creating and controlling MAC can be easily adopted in labs without microfabrication infrastructures, and they can be mastered by people with little prior experience in microfluidics., Magnetically actuated microscopic artificial cilia were implemented in millimeter‐scale culture wells for Scenedesmus subspicatus, and they were able to increase the growth rate of the microalgae by nearly ten times. Hydrophobicity of the cilia surface was also found to significantly influence the enhancement of growth. The technique of creating and controlling the artficial cilia can be easily mastered and adopted in labs without microfabrication infrastructure.

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.

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.

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.

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.

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.

Fibreglass, foam, mineral fibres and their composites are the conventional materials used in applications that require absorption of sound. However, due to the health risks associated with the trad...

The paper presents the results of an experiment on the effect of cold plasma (He + O2 and He + Air) generated in a radio frequency cold atmospheric plasma jet on the process of germination of onion cv. Wolska (Allium cepa L.) seeds. In order to determine the impact of the gas flow on the seed surface, CFD simulations and Schlieren imaging were performed and surface characteristics were studied using a digital microscope. Plasma treatment of the seeds was carried out four times (2, 5, 10 and 15 s) with one control group. Pre-sowing plasma stimulation of seeds improved the germination capacity and germination energy for all tested groups in comparison to the control. The best germination capacity and energy were obtained for seeds stimulated with 10 s of plasma treatment. Analysis of the data showed a statistically significant impact of plasma treatment on the onion seed’s germination parameters. Plasma treatment did not induce significant changes on the seed surface, as microscope images showed but length of all plasma-treated seedlings increased in comparison to control.

Fibers obtained from fruits, stem, and plant leaves are nature-based fibers and are known as natural fiber. Due to their versatile properties such as good mechanical behavior, low cost, eco-friendly, less dense, biodegradable, etc. natural fibers are getting focus amongst researchers. Since the density of bio-composites reinforced by natural fiber is significantly inferior to other traditional materials they satisfy the automotive need of high-performance vehicle parts/components of lightweight. To decrease the cost and weight of the vehicle automotive manufacturers are extensively utilizing the natural fibers (as interior insulation, seat bottom, door panels, dashboard, body panels, boot liner, etc.). Although, the composite of natural fiber has few shortcomings like poor chemical and fire resistance, poor interfacial bonding among matrix and fiber, moisture intake. Thus, natural fiber is required to be surface treated. Among the finest method for physical treatment is plasma treatment. Herein plasma which participates within surface modification directly is produced within the vacuum chamber by the ionization of the gas. The improved interfacial bonding in fiber composite is obtained as a result of surface treatment of plasma, which results in increase mechanical strength. Effect of surface treatment of plasma on several natural fiber is included in this paper and the aim of this review paper is to occupy the literature gap through this paper.

A selective photoelectrochemical (PEC) sensor has been designed for the signal-on detection of H2S using g-C3N4 nanosheets that were treated with N2 plasma for depositing Cd probes. It was discovered that the yielded Cd/N@g-C3N4 nanocomposites could present enhanced photocurrents of specific responses to H2S under visible light irradiation, in contrast to the ones without the pretreatment of N2 plasma showing no H2S response. Herein, the Cd probes deposited on g-C3N4 nanosheets might react with H2S to generate CdS on Cd/N@g-C3N4, forming the efficient heterojunctions. Especially, the plasma-derived N contents might act as the "bridge" to promote charge transfer between the generated CdS and g-C3N4, resulting in the "signal-on" PEC responses to H2S. A selective PEC sensor was thereby developed for sensing H2S of concentrations linearly ranging from 40.0 to 10,000 pM, with a detection limit of about 21 pM. Also, the feasibility of sensing H2S in industrial waste gas was demonstrated by recovery tests. More importantly, this N2 plasma treatment route for g-C3N4 nanosheets may open a new door toward the construction of a Cd probe-based heterojunction for the signal-on PEC sensing platform, which is promising for the wide application in the fields of environmental monitoring, food safety, and biomedical analysis.

This work introduces a novel method of low-temperature (70 °C) ambient-air plasma treatment for the rapid fabrication of mesoporous titania/polysiloxane thin films in perovskite solar cells. The me...

The objective of the study was to investigate the bactericidal effectiveness of atmospheric pressure nonthermal plasma (NTP) on biofilms of Staphylococcus aureus and Escherichia coli formed on the surface of surgical sutures. Tests were carried out for polyamide nonabsorbable monofilament sutures and mid-term absorbable synthetic monofilament sutures made of glyconate. Dielectric barrier discharge reactor providing atmospheric air plasma and constant discharge power density of 70 mW/cm2 was used in the experiments. The colonization/decontamination efficacy was quantified by colony-counting assay. It was shown that decontamination efficacy of the studied surgical sutures was time-dependent i.e. the effect was more visible for longer exposure times ranging from 60 to 360 s. It was proposed to combine plasma treatment with washing the biofilms with a phosphate buffered saline to to allow the plasma to interact with cells in the deeper layers of bacterial biofilm. The application of the original method of treatment of biofilms was more effective than the separate plasma treatment. As a result, the lethal effect was most often achieved after 300 s regardless of the type of suture and biofilm. The results of the comparative studies on the decontamination efficiency of polymeric surgical suture surface by disinfectants and NTP technique have shown unequivocally that plasma treatment is the most effective way to deactivate bacterial cells and ensures a lethal effect for most of the tested cases.

Zinc oxide nanoparticles (ZnO-NPs) were in situ synthesized on the polyester fabric with different alkaline and plasma treatment orders. Diverse alkaline in various percentages along with different...

Cherry samples were treated with cold plasma under different voltages (40, 60, 80 kV) and different treatment durations (60, 80, 100, 140 s), then stored in a refrigerator at 0 ℃. Data on the decay rate, respiration rate, and physiological properties of the cherries and their correlational relationships after different treatments of cold plasma were collected under the conditions of ambient temperature and dry air. The decay rate, respiration rate, total soluble solids, total phenol, flavonoids, anthocyanin, VC, titratable acidity, firmness, and a* value were investigated at regular intervals to analyze the quality of the cherries under different treatment conditions. Additionally, the total colony number was estimated at the end of storage. The results indicated that cold plasma treatment under moderate conditions was effective for prolonging cherry storage, inactivating microorganisms, decreasing the decay rate, and inhibiting respiration with either no compromise on the cherry quality or only a slightly noticeable influence. A significant positive correlation was found between the decay rate and respiration rate, as well as between the VC content and titratable acidity. Antioxidant contents and firmness were found to be negatively correlated with the a* value. In conclusion, this study demonstrated that cold plasma has potential applications in the storage and preservation of cherries.

Background Superwettability is a particular state of wettability that has recently contributed to many technological breakthroughs. Nowadays, lots of artificial superwettability systems are fabricated biomimetically, wherein hierarchical micro–nano structures play a substantial role. Scope and approach There are several procedures for manufacturing super(-non)-wettable surfaces, all of which aim to develop surface micro-protrusions with specific average distance and aspect ratio, on which nanoscale roughness is situated. The most common types of these methods are templating, layer-by-layer assembly, electrospinning, plasma treatment, etching, lithography, sol–gel method and coating. Contact angle (CA) and CA hysteresis are two critical measurements that are taken to evaluate the superwettability systems. The development of superwettability strategy in the food engineering is still in the preliminary stages and can be categorized into two main groups: Ⅰ. Superwettability associated with solid–liquid interfaces, which could be gainfully employed in food packaging technology, food coating technology, food processing equipment and liquid–liquid separation; Ⅱ. Food-grade superwetting agents for colloidal systems. Key findings and conclusions superwettability-based systems have recently attracted much attention due to their potential applications in the food industry, including self-cleaning, anti-fogging, anti-icing, anti-bacterial action, anti-fouling, fluidic drag reduction, anti-corrosion, oil–water separation and so on. Superwettability strategy could play a prominent role in the future of food processing and preservation.

Seed modification by atmospheric pressure non-thermal plasma treatment was tested on pine species. The Diffuse Coplanar Surface Barrier Discharge (DCSBD) with expose times of 0 s, 1 s, 3 s, 5 s, 10 s, 30 s, 60 s was used on seed treatment of Pinus sylvestris, Pinus nigra and Pinus mugo. The effect of plasma treatment on the chemical bonds on the seed surface was studied using the Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR). Characteristics of seed germination and early growth were measured. ATR-FTIR surface diagnostics did not show any damage. Changes in the peak intensities indicated the presence of oxygen and nitrogen-containing groups, or a reduction of the lipid layer on the surface. Various statistically significant effects of the three species of seeds treated with DCSBD treatment were recorded. No significant differences were found between control sample and plasma treated ones, but some positive trends were obtained. Positive trends were recorded in germinated and growing seeds of all three species mainly after 3 s exposures. Exposure times from 10 s had an inhibitory effect. Based on the results obtained, it can be recommended that forest nurseries performance of nonthermal plasma modification of seeds should be evaluated to measure the durability of the observed growth characteristics.

This investigation highlights argon plasma treatment on Poly-aryl-ether-ketone (PAEK) and carbon fibre (CF) surface. The PAEK and CF surface is modified for 300 sec and the change in physiochemical and mechanical properties were investigated through Fourier Transform Infrared Spectroscopy (FTIR), Dynamic Contact angle, Atomic Force Microscope (AFM) and Tensile Test. FTIR of surface modified PAEK revealed the stretching of C-H, C=C and C=O functional groups. A reversal phenomenon of increased surface energy was observed through dynamic contact angle study of CF and to further examine the surface energy effect, AFM analysis on CF was carried out revealing increased roughness with numerous micro dents formation. PAEK/CF composite samples were fabricated through compression moulding technique. The change in mechanical properties due to surface modification were analysed through Tensile testing on surface modified PAEK/CF sample and untreated PAEK/CF samples. The surface treated PAEK/CF showed increased tensile strength than untreated PAEK/CF. The argon plasma treatment helped in creating depth striations that lead to better interlocking of resin matrix with the reinforced CF. The fracture surface was examined through Filed Emission Scanning Electron Microscope (FE-SEM) wherein the Micrographs of the tensile tested samples indicated failure of composite due to fibre breakage.

The harmless treatments of medical waste have significantly drawn people’s attention owing to their risks to health-care staff, the public, and the environment. The traditional thermal technology for processing medical waste may cause indispensable secondary pollution such as dioxin, furan, and heavy metals, and infectious materials that may remain in the solid residual. Thermal plasma technologies offer advantages of effectively treating medical waste due to its high temperature and energy density, lower pollutant emissions, rapid start-up and shut-down, and smaller size of the installation. These benefits play roles in the treatment of medical waste on-site or off-site, especially when somewhere encounters an abnormally sharp increase in medical waste. This paper mainly introduces the typical thermal plasma processes of medical waste and its central component, plasma furnace. Meanwhile, how process parameters influence the formed gaseous and solid products, the performances of mass and volume reduction, pathogen destruction, and energy recovery, are discussed in detail. Finally, the mechanism of the thermal plasma process is also analyzed.

The impacts of a low temperature plasma treatment on wheat seed germination and field growth were investigated using a plasma system about the first generation (T0), the second generation (T1) and the third generation (T2). Untreated wheat seeds were set as the control (CK). Plasma treatments of 80 W and 100 W were employed during the experiments. Germination characteristics, seedling growth parameters, biological characters and yield components were measured following the plasma treatments. The wheat seed germination index, plant height, tiller, growth and grain number obviously changed significantly after the low-temperature plasma treatment. Furthermore, the moderate-intensity plasma had an active impact on wheat seed germination and growth. The results showed that the theoretical yield of T0 significantly increased by 8.92% and 8.14%, while the actual yield increased by 8.12% and 6.10% compared with untreated. The theoretical yield of T1 increased by 5.69% and 6.62%, while it increased by 3.70% and 0.45% for T2. The actual yield of T1 increased by 5.75% and 4.94%, while it increased by 3.81% and 0.82% for T2. Plasma treatment exhibited the following trend of increasing: T0 > T1 > T2 > CK. We conclude that the effects of low-temperature plasma on the biological characteristics and yield components of wheat seeds exhibited a consistent trend from T0 to T1 to T2.

合成气是一种CO和H2的混合气, 是工业上生产烯烃、液体 燃料、聚合物、药物等产品的重要原料. 通过电化学还原的方法 将CO2转化为合成气, 不仅能够减少大气中的CO2含量, 同时还能 缓解能源危机. 但是目前仍然缺乏廉价高效的电催化剂来实现可 控比例CO/H2的合成. 因此, 我们发展了一种简易的等离子体处理 策略, 利用氮掺杂碳纳米管阵列作为电催化剂, 通过电化学CO2-H2O还原制备CO/H2比例可控的合成气. 在不同的等离子体处理条 件下, CO/H2比例的范围可达0.55–3.03, 符合下游化工生产的原料 气标准. 通过优化等离子体处理条件, CO的法拉第效率最高可达 75%, 并且能够维持稳定性长达10 h. 通过研究氮掺杂的碳纳米管 的结构随处理条件的变化, 并结合其CO2还原活性, 我们推断出氮 掺杂碳纳米管中的吡啶氮有利于CO2转化为CO, 而吡咯氮和sp2平 面外的碳则有利于氢气的产生. 利用等离子体处理的方法能够有 效调节催化剂中各活性组分的比例, 从而调控CO2还原反应和析氢 反应的速率, 最终实现CO/H2比例可控的合成气制备.

Thermodynamic calculations and experiments on plasma gasification of wood waste have been conducted. On the basis of a verified TERRA universal thermodynamic-calculation program, the authors have conducted an experiment on plasma recycling of agricultural waste. No detrimental impurities were found in the products of plasma recycling.

Global food production sustainability and the demand for fresh and nutritious food necessitate the development of novel technologies to provide food with a long shelf life. Hurdle technologies combing several interventions can ensure microbial safety without inducing notable changes to food quality. Cold plasma, as a promising nonthermal technology, has increasingly attracted attention in food industry. Recently, cold plasma–based hurdles have been proposed as novel intervention strategies for microbial decontamination. This review summarizes currently existing cold plasma–based hurdle strategies, including thermal treatment and nonthermal techniques (e.g., organic acids, essential oils, ultrasound) that have been reported in the literature. In addition, we highlight some critical issues, including the microbial stress response, the processing parameters, and the effects on food quality, that need to be taken into account during the optimization and implementation of cold plasma–based hurdles. Cold plasma–based hurdles overcome certain limitations of individual cold plasma treatment to improve the inactivation efficacy and retain the maximum food quality attributes.

Monolayer two-dimensional transition-metal dichalcogenides, such as tungsten disulfide (WS2), are regarded as promising candidates for optoelectronic and electronic applications. Although theoretic...

Plasma treatment of mulberry silk fabric was carried out in an indigenously developed plasma reactor in the mixture of helium (He) and commercial fluorocarbon gas at atmospheric pressure. Optical e...

The co-modulation of the oxygen-containing and amino groups in the polymeric semiconductor graphitic carbon nitride (g-CN) has increasingly become a common concern toward advanced catalysis, energy and biomedicine applications. The intensive understanding of the existence state of oxygen-containing and amino groups in the polymeric structure of g-CN and the controllable methods of modulating these groups is highly desirable. Herein, a rational industrially applicable plasma strategy was designed and applied for controllable modulation of oxygen-containing and amino groups in g-CN within 10 min. X-ray diffractometry, Fourier transform infrared spectrometry, and X-ray photoelectron spectroscopy results indicated that the oxygen-containing and amino groups were controllably introduced after plasma treatment. Transmission electron microscopy, atomic force microscopy and N2 adsorption-desorption measurements verified the ultra-thin and two-dimensional in-plane mesoporous morphology of the optimized g-CN-O-NH2. As a result, the rational g–CN–O-NH2 performed well in Cr(VI) photoreduction, photocatalytic bacterial disinfection and inactivation of tumor cells. The remarkable extensively applicable photocatalytic activity can be ascribed to the fast charge carrier transfer benefiting from the enriched preferable internal edge sites and ideal joint effect of internal –NH2 and OH- groups, as confirmed by the significantly weakened PL fluorescence intensity and prolonged fluorescence lifetime of the excited states under visible light irradiation. This work provides an impressive industrially applicable strategy for the structure optimization and functional groups modulation of polymeric materials towards enhanced electronic and catalytic performances.

A low equivalent-oxide-thickness of 0.58 nm and a low gate leakage current density of $\sim 2\times 10^{-{5}}$ A/cm2 at VG = VFB – 1 V in p-substrate Ge (pGe) MOS device can be simultaneously achieved by a hydrogen plasma (H*) treatment on GeO2 interfacial layer (IL). It is found that the removal of GeOx with low oxidation state in GeO2 IL play crucial roles on electrical characteristics of pGe MOS device. Through a H* treatment, the electrical and reliability characteristics are improved by a GeO2 IL with high oxidation state. Therefore, a GeO2 IL with H* treatment is promising for high performance pGe MOS devices.

We studied the effects of nonthermal plasma (NTP) treatment on various parameters of early germination stages of Pinus nigra seeds. In the experiment, the diffuse coplanar surface barrier discharge (DCSBD) with treatment time periods of 0, 1, 3, 5, 10, 30, and 60 s was used. Changes on the plasma-treated seed surface were studied by attenuated total reflectance-Fourier transform infrared spectroscopy. Seed germination, germination rate, germination index, length of seedling, dry seedling weight, and seedling vigor index I and II were determined in a growth test under laboratory conditions. Various statistically significant effects of seed exposure to DCSBD plasma treatment were recorded. A positive reaction was observed in the germinated seeds after exposure for 1- and 5-s. Longer exposure time periods had a rather inhibitory effect. The performance of forest nurseries of NTP modification of seeds should be evaluated in order to measure the durability of the observed growth characteristics. The potential of NTP treatment on seeds in plant ecology in future is highlighted.

The effect of an electrolytic-plasma treatment on the structure of steel 45G is studied. The possibilities of computer technologies for description of steel structures are considered.

Electromagnetic wave shielding effectiveness of the nonwoven fabrics was measured in the wide operating frequency range, namely 0.4GHz to 20GHz. The shielding effectiveness of the nonwoven fabric was below 45dB in the range of 0.04GHz to 15GHz and then it increased to above 45dB in the range of 15GHz to 20GHz. To enhance the electromagnetic wave shielding effectiveness of the nonwoven fabrics, 3 minutes H2 plasma treatment of the nonwoven fabrics was carried out under the microwave plasma-enhanced chemical vapor deposition system. By H2 plasma treatment, the shielding effectiveness of the nonwoven fabrics was greatly enhanced in the whole operating frequency range. The surface electron conductivity of the nonwoven fabrics was also enhanced from 2.11×103 S/m to 3.02×103S/m by H2 plasma treatment. The surface and cross sectional morphologies of the nonwoven fabrics with or without H2 plasma treatment were investigated and compared with each other. Crystal structure variation of the nonwoven fabrics by H2 plasma treatment was also investigated. Based on these results, the cause for the enhancement of the shielding effectiveness of the nonwoven fabrics by H2 plasma treatment was suggested and discussed.

Plasma treatment of porous polymer materials is a promising method for creating new materials that can be widely applied, in particular, in medicine and for development of new types of biocompatible and biodegradable polymer materials. In this work, plasma treatment of porous polymer materials is studied to reveal the breakdown conditions and to optimize this method of treatment. Experiments have been performed to determine the breakdown voltage in the discharge gap of a pulse barrier discharge at different air pressures and different gaps in the region of the minimum of the Paschen curve. An approximation of the Paschen curve with the variable γ is proposed, which provides good agreement with the experimental results. A technique of barrier discharge treatment of the inner surface of pores in a dielectric material based on optimizing the pressure inside the pores is proposed. The treatment of few-micron pores requires pressures substantially above atmospheric. The first results demonstrating the possibility of modifying the bulk of the polymer material by means of the barrier discharge treatment at the time when the gas pressure in the discharge chamber drops are obtained.

Pd-doped SnO2 nanofibres were prepared by electrospinning and magnetron sputtering. It was found that the efficiency of gas sensing properties in these fibres depends primarily on the density of oxygen vacancies, which can be regulated by plasma treatment. We demonstrated that moderate plasma treatment can increase the oxygen vacancy as well as improve the gas sensing performance of SnO2. However, excessive plasma treatment led to the production of other substances that deteriorated the gas sensing performance. Furthermore, the best results for hydrogen gas sensing were obtained when the nanofibres were subjected to plasma treatment for 1 min. The fabricated material demonstrated a response of more than 53 for 500 ppm hydrogen at the optimum temperature (130 °C), which is a significant improvement as compared to sensors without plasma treatment. Evidently, plasma treatment is an effective method to further enhance the sensing properties of the fabricated nanofibres.

There are growing advantages of using electrospun poly(ethylene terephthalate) (PET) mats for tissue engineering purposes. However, because of poor surface physicochemical properties, using PET as a biomaterial may have some serious problems, such as poor wettability, inappropriate surface roughness and consequently weak cell attachment. To avoid such complications, in the present study, a combination of nanosecond pulsed plasma surface modification and chitosan coating was used as a versatile solution for tackling the mentioned problems. The effects of plasma treatment and chitosan coating were characterized by scanning electron microscopy, goniometry, weight loss study and X-ray photoelectron spectroscopy. The results showed that plasma modification resulted in the introduction of active polar oxygen (O)-containing functional groups onto the PET surface. The PET mat exhibited over 30 and 25% enhancement of hydroxyl and carboxyl groups after plasma treatment, respectively. Consequently, the oxygen/carbon (C) ratio increased from 0·36 to 0·73. These modifications led to improvement of physical properties, such as a significant increase in wettability and chitosan deposition. Chitosan coating introduced new nitrogen (N)-containing functional groups, which were absent in the uncoated PET. Plasma treatment increased the nitrogen/carbon ratio of chitosan-coated samples by a factor of 2. The obtained results suggest an enhancement in surface physicochemical properties with noteworthy potential applications in tissue engineering scaffolds.

Silicon nanowires (SiNWs) are fabricated by Ag assisted chemical etching and are treated with hydrogen plasma created by electron cyclotron resonance (ECR) plasma system at 600 watts microwave power for various time durations (0–30 min). The hydrogen plasma exposure on the surface of the SiNWs reduced the surface roughness and increased the crystalline nature. SEM analysis revealed that the diameter of the SiNWs decreased on plasma exposure. The electrical conduction measurements suggested that the hydrogen plasma exposure for 5 min on the SiNW surface enhanced the electrical conductivity when compared to as fabricated SiNW surface. The hydrophobic nature of fabricated SiNWs was transformed to hydrophilic at plasma exposure for lower time duration. On plasma exposure of NWs for 30 min the sample turned hydrophobic. Study of different properties of the SiNWs before and after plasma treatment revealed that there is pronounced effect of plasma on the nature of SiNWs.

In this paper, the results of decolourisation of Reactive Orange 16 (RO 16), Reactive Blue 19 (RB 19) and Direct Red 28 (DR 28) textile dyes in aqueous solution by plasma needle are presented. Treatment time, feed gas flow rate (1, 4 and 8 dm3 min-1) and gas composition (Ar, Ar/O2) were optimized to achieve the best performance of the plasma treatment. An artificial neural network (ANN) was used for the prediction of parameters relevant for the decolourisation outcome. It was found that more than 95 % decolourisation could be achieved for all three dyes after plasma treatment, although the decolourisation of DR 28 was much slower than those of the other two dyes, which could be explained by the complexity of its molecular structure. It was concluded that the oxidation was very dependent on all three mentioned parameters. The ANN predicted the treatment time as the crucial factor for decolourisation performance of RO 16 and DR 28, while the Ar flow rate was the most relevant for RB 19 decolourisation. The obtained results suggest that the plasma needle is a promising tool for the oxidation of organic pollutants and that an ANN could be used for optimization of the treatment parameters to achieve high removal rates. [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172023 and Grant no. III43007]

Triboelectrification is a novel technology to harvest electricity from unexploited environmental energy. Its efficiency depends on the area, morphology and charges on the in-contact surfaces. Many studies are carried out in order to increase the efficiency of the triboelectric generators by increasing the surface area or varying the morphology but the charge density is not properly focused until date. Herein, we will discuss the effect of the artificial charges induced on the in-contact surface. For that purpose, plasma treatment was used to increase the surface charge density of the in-contact surface. The increment in the charge density actually helped us to increase the efficiency of triboelectric generator even without changing the dimensions of the device. The output power was increased up to two folds as compared to the untreated device. At the end, we also charged the capacitor in order to compare the charge storing efficiencies of both devices. We found that the untreated device and the plasma treated device (15 min and 30 min) stored voltages up to 6 V, 9 V and 12 V respectively. This type of study will surely support the researchers to enhance the triboelectric current generation efficiency even without increasing the size of the device.

The paper investigates the effect of plasma treatment of basalt fiber on its wettability, which is determined by the ability to absorb water. As the treatment time increases the wettability becomes higher, up to 10 minutes. The wettability-treatment power dependence passes through a maximum. The highest value is observed at a treatment power of 0.6 kW both on the day of treatment and after a 5-day rest period. A further growth in power not only does not increase this value, but in fact decreases it. The retreatment after a 5-day curing period yields lower results, but remains sufficiently high. The highest wettability is observed at a treatment power of 0.6 kW, gas flow rate of 0.04 g/s, chamber pressure of 20 Pa, air/argon mixture (1:1) as plasma support gas. The strength of concrete specimens BST V40 P2 was tested with two treatment modes: in mode 1 the treatment time was 10 minutes, the treatment power was 1.5 kW; and in mode 2 the treatment time was 5 minutes, the treatment power was 0.6 kW, with the addition of plasma treated basalt fiber (0.5 and 3 mass percent). Concrete has the highest strength when basalt fiber (3 mass percent) is subjected to plasma treatment in mode 2. In addition, the strength increases by 18 mass percent in comparison with the reference.

The influence of the surface preparation method of fiberglass VPS–53K on the adhesive strength is researched. To prepare the surface, both standard methods (degreasing, sanding, sandblasting, sacrificial layers) and ultraviolet and normal-pressure plasma treatment are used. The strength of adhesive joints is evaluated by measuring peel resistance according to GOST (State Standard) R 57832–2017 (ASTM D3167). It is shown that the most effective surface preparation method for bonding is normal-pressure plasma treatment. Through this process the fiberglass surface becomes activated, the fiberglass roughness changes conditionally warpwise and fillingwise, which, together with the ongoing physicochemical processes on the fiberglass surface, leads to an increase in the strength of adhesive joints. The application of normal-pressure plasma improves the wettability of the treated surface with cold-setting liquid adhesives.

Cardiovascular diseases, especially ones involving narrowed or blocked blood vessels with diameters smaller than 6 millimeters, are the leading cause of death globally. Vascular grafts have been used in bypass surgery to replace damaged native blood vessels for treating severe cardio- and peripheral vascular diseases. However, autologous replacement grafts are not often available due to prior harvesting or the patient's health. Furthermore, autologous harvesting causes secondary injury to the patient at the harvest site. Therefore, artificial blood vessels have been widely investigated in the last several decades. In this review, the progress and potential outlook of small-diameter blood vessels (SDBVs) engineered in vitro are highlighted and summarized, including material selection and development, fabrication techniques, surface modification, mechanical properties, and bioactive functionalities. Several kinds of natural and synthetic polymers for artificial SDBVs are presented here. Commonly used fabrication techniques, such as extrusion and expansion, electrospinning, thermally induced phase separation (TIPS), braiding, 3D printing, hydrogel tubing, gas foaming, and a combination of these methods, are analyzed and compared. Different surface modification methods, such as physical immobilization, surface adsorption, plasma treatment, and chemical immobilization, are investigated and are compared here as well. Mechanical requirements of SDBVs are also reviewed for long-term service. In vitro biological functions of artificial blood vessels, including oxygen consumption, nitric oxide (NO) production, shear stress response, leukocyte adhesion, and anticoagulation, are also discussed. Finally, we draw conclusions regarding current challenges and attempts to identify future directions for the optimal combination of materials, fabrication methods, surface modifications, and biofunctionalities. We hope that this review can assist with the design, fabrication, and application of SDBVs engineered in vitro and promote future advancements in this emerging research field.

International audience; In this study, a flexible multifunctional fibrous membrane for heterogeneous Fenton-like removal of organic and pathogenic contaminants from wastewater was developed by immobilizing zerovalent iron nanoparticles (Fe-NPs) on an amine/thiol grafted polyester membrane. Full characterization of the resulting polyester membranes allowed validation of successful grafting of amine/thiol (NH 2 or SH) functional groups and immobilization of Fe-NPs (50-150 nm). The Fenton-like functionality of iron immobilized fibrous membranes (PET-Fe, PET-Si-NH 2-Fe, PET-NH 2-Fe, and PET-SH-Fe) in the presence of hydrogen peroxide (H 2 O 2) was comparatively studied in the removal of crystal violet dye (50 mg L À1). The effect of pH, amount of iron and H 2 O 2 concentration on dye removal was systematically investigated. The highest dye removal yield reached 98.87% in 22 min at a rate constant 0.1919 min À1 (R 2 ¼ 95.36) for PET-SH-Fe providing 78% toxicity reduction assessed by COD analysis. These membranes could be reused for up to seven repeated cycles. Kinetics and postulated mechanism of colour removal were proposed by examining the above results. In addition, the resultant membranes showed substantial antibacterial activity against pathogenic bacteria (Staphylococcus epidermidis, Escherichia coli) strains studied through disc diffusion-zone inhibitory and optical density analysis. These findings are of great importance because they provide a prospect of textile-based flexible catalysts in heterogeneous Fenton-like systems for environmental and green chemistry applications.

Cold plasma technologies are an efficient approach to improve the germination properties of seeds, especially in a stacking configuration within a dielectric barrier device. In such dry atmospheric plasma priming process, we show that a He-N2 plasma treatment of 20 min can reduce the median germination time of lentil seeds from 1420 min to 1145 minutes, ie a gain in vigor of 275 min (or +19.4 %). Considering that this result depends on the plasma-seed interaction and therefore on the contact surfaces between the seeds and the plasma, a topographic modeling of a 100 seeds-stack is performed in the dielectric barrier device. This model drives to the distinction between the seed-seed contact surfaces (276 contacts standing for a total area of 230.6 mm2) and the seed-wall contact surfaces (134 contacts standing for a total area of 105.9 mm2). After a single plasma treatment, the outer envelope of each seed is 92% exposed to plasma: a value high enough to support the relevance of the plasma process but which also opens the way to process optimizations. In this outlook, we propose to replace the single 20-minute plasma treatment by a "plasma sequence", ie a succession of shorter plasma treatments whose total duration remains 20 min. Between two successive plasma treatments, the seeds can follow either a trapping procedure (seeds in same positions and orientations) or a randomizing procedure (seeds in same positions but reoriented) or a stirring procedure (seeds vigorously shaken). A sequence of 10 plasma treatments (upon 2 min) separated by short stirring procedures leads to a gain in vigor as high as 405 min vs 275 min for a single plasma treatment of 20 min. We propose to understand these results by correlating the gain in vigor with the water uptake of the seeds and the wettability state of their coating., Comment: 16pp

Fe3Si films are deposited onto the Si(111) wafer using sputtering with parallel facing targets. Surface modification of the deposited Fe3Si film is conducted by using a microwave plasma treatment under an Ar atmosphere at different powers of 50, 100 and, 150 W. After the Ar plasma treatment, the crystallinity of the coated Fe3Si films is enhanced, in which the orientation peaks, including (220), (222), (400), and (422) of the Fe3Si are sharpened. The extinction rule suggests that the B2–Fe3Si crystallites are the film’s dominant composition. The stoichiometry of the Fe3Si surfaces is marginally changed after the treatment. An increase in microwave power damages the surface of the Fe3Si films, resulting in the generation of small pinholes. The roughness of the Fe3Si films after being treated at 150 W is insignificantly increased compared to the untreated films. The untreated Fe3Si films have a hydrophobic surface with an average contact angle of 101.70°. After treatment at 150 W, it turns into a hydrophilic surface with an average contact angle of 67.05° because of the reduction in the hydrophobic carbon group and the increase in the hydrophilic oxide group. The hardness of the untreated Fe3Si is ~9.39 GPa, which is kept at a similar level throughout each treatment power.

Selective altering of surface wettability in microfluidic channels provides a suitable platform for a large range of processes, such as the phase separation of multiphase systems, synthesis of reaction controlled, nanoliter sized droplet reactors, and catalyst impregnation. Herein we study the feasibility to tune the wettability of a flexible cyclic olefin copolymer (COC). Two methods were considered for enhancing the surface hydrophilicity. The first is argon/oxygen plasma treatment, where the effect of treatment duration on water contact angle and COC surface morphology and chemistry were investigated, and the second is coating COC with GO dispersions of different concentrations. For enhancing the hydrophobicity of GO-coated COC surfaces, three reduction methods were considered: chemical reduction by Hydroiodic acid (HI), thermal reduction, and photo reduction by exposure of GO-coated COC to UV light. The results show that as the GO concentration and plasma treatment duration increased, a significant decrease in contact angle was observed, which confirmed the ability to enhance the wettability of the COC surface. The increase in hydrophilicity during plasma treatment was associated with the increase in surface roughness on the treated surfaces, while the increase during GO coating was associated with introducing oxygen-containing groups on the GO-coated COC surfaces. The results also show that the different reduction methods considered can increase the contact angle and improve the hydrophobicity of a GO-coated COC surface. It was found that the significant improvement in hydrophobicity was related to the reduction of oxygen-containing groups on the GO-coated COC modified surface.