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Purpose: To investigate the influence of contamination and different cleaning methods on resin bonding to cobalt-chromium (CoCr) alloy disks. Materials and Methods: A total of 160 CoCr disks were divided into 3 groups. The first group (N = 64) was air abraded with alumina particles; the second group (N=64) was air abraded and contaminated with silicone disclosing agent and saliva; the third group (N=32) was neither air abraded nor contaminated. The first two groups were divided into 4 subgroups (N = 16) according to the cleaning method: ultrasonic bath in 99% isopropanol, use of a cleaning suspension of zirconium oxide particles, use of a cleaning suspension based on 10-MDP salt, and treatment with atmospheric plasma. The third group was divided into 2 subgroups (N = 16): treatment with atmospheric plasma and no treatment. All CoCr specimens were bonded to plexiglas tubes filled with a bonding resin that contained phosphate monomer. Tensile bond strength (TBS) was examined by tensile testing after 3 and 150days of water storage plus 37,500 thermal cycles (N = 8). Results: After contamination, TBS was significantly reduced after 150days of water storage. Groups without air abrasion showed initially low TBS and debonded spontaneously after 150days of water storage. Conclusion: None of the cleaning methods was able to remove saliva and silicone disclosing agent on CoCr-alloy surfaces. Surface activation by plasma treatment has no long-term effect on the bond strength. [ABSTRACT FROM AUTHOR]

The polyester fabric was subjected to atmospheric plasma and impregnated with commercially available 3‐hydroxyphenyl phosphinyl‐propanoic acid (3HPP) as flame retarding agent by high‐temperature high pressure (HTHP) dyeing method. Various concentrations of 3HPP in water, up to 4% w/v, were applied using the HTHP method. It was observed that the plasma treatment not only enhanced wettability and wicking but also facilitated increased pickup of 3HPP onto the polyester. The treatment exhibited a noteworthy enhancement in the limiting oxygen index (LOI), rising from 20.8% for the untreated control fabric to 30% for the fabric treated with plasma and a 4% 3HPP solution. Additionally, the application of 3HPP without plasma treatment did not yield significant improvements in flame‐retardant (FR) properties. The combined treatment of plasma and 3HPP resulted in an LOI of 29% with a 2% 3HPP treatment, while at the same concentration without plasma treatment, the LOI value was 26.8%. The heightened LOI was primarily attributed to the presence of phosphorus, as confirmed by high‐performance liquid chromatography and energy‐dispersive X‐ray spectroscopy. Additionally, the wash durability assessment of plasma‐processed and 3HPP‐treated samples demonstrated sustained flame retardancy, with an LOI of approximately 28% even after undergoing 20 wash cycles. Vertical flammability and cone calorimetry also confirm improved FR properties after treatment. Remarkably, the mechanical properties and surface morphology of the fabric remained unaltered following both plasma and chemical treatments. Highlights: Easy and cost‐effective technique for the downstream process for FR polyester fabric.FR agent during polymerization has the disadvantage of lower molecular weight.Potential for producing FR industrial polyester fabric.Post‐plasma treatment improves the washing fastness.The mechanical and comfort properties remain intact during the process. [ABSTRACT FROM AUTHOR]

An experimental study was conducted to test the effect of changing the frequency of a 10 kV alternating voltage source on the properties of a plasma jet. Optical emission spectra of the plasma were recorded and analyzed. In plasma physics, the electron temperature and density are key parameters. These were determined using a Boltzmann plot and the Stark broadening of the argon line at 763.153 nm, respectively. As the frequency of the alternating voltage source was increased from 10 to 30 kHz (in increments of 5 kHz), the electron temperature increased from 0.995 to 1.357 eV and the electron density rose from 12.027 × 1017 to 12.838 × 1017 cm−3. A strong correlation between the plasma parameters and the frequency of the alternating voltage source was evident. Measurements were also taken on the length of the plasma torch, which was found to grow from 0.041 to 0.051 m as the frequency of the supply voltages was increased. Furthermore, the effect of plasma on the temperature of a silicon target was investigated for a range of frequencies of the supply voltage. It was observed that a slight increase in temperature occurred with increasing frequency, at a constant argon gas flow rate. The effect of plasma jetting on a silicon target was studied at a fixed voltage frequency and a variable gas flow rate. Only a small increase in target temperature was observed. This ensures that no damage or unwanted effects occur on the material being processed. [ABSTRACT FROM AUTHOR]

In the context of human active response to exponentially increasing data volumes, memristors have emerged as a focal point in systematic problem‐solving approaches. Particularly, organic memristors, characterized by excellent scalability, flexibility, and 3D stacking capabilities, have shown its tremendous potential in innovative electronic applications. However, the modulation of molecular assembly and interface interaction at the electrode surface poses a challenging task, despite their crucial role in determining the memristive performance. Herein, a collaborative method involving hydrophobic molecular design and interface engineering is proposed to generate high‐quality nanofilms with optimal photoelectric and electrochemical properties. By subjecting the bottom electrode to O2 plasma treatment and chemical modification using a hydrophobic ionic liquid poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide (PTFSI), the hydrophobic compound DN demonstrates exceptional affinity and stronger intermolecular interactions with the electrode surface. Consequently, the two‐terminal device array comprising Al/DN@PTFSI/ITO exhibits robust non‐volatile write‐once‐read‐many times (WORM) memory behavior, resulting in a tripling production yield from 30% to 92% along with a lower threshold voltage of 1.5 V, higher ON/OFF current ratio of 103 and excellent stability. This study presents a versatile approach to optimize the film assembly and material/electrode interface, thereby accelerating the development of organic memristors toward future applications. [ABSTRACT FROM AUTHOR]

Featured Application: Use of ancient materials for new technologies. In recent decades, fabric-dyeing processes involved greener processes because, since ancient times, dyers used mordants based on metals to make the color better adhere to the textile fibers, but this is the reason for their increased pollution. To develop new strategies, attention was focused on finding the best condition for a dyeing method for natural fibers of vegetable and animal origin (cotton and wool) using an ancient natural dye known as folium. Folium was used mostly in miniature painting in an attempt to avoid the use of classical mordants and solvents. To this purpose, plasma treatment and chitosan coating were employed. Firstly, the textile fibers were analyzed through infrared spectroscopies to verify surface modifications; subsequently, the post-treatment morphological variations were observed via scanning electron microscopy. Both techniques highlighted a significant variation of the surface functional groups due to plasma treatments with He-O2 mixtures, which allowed a greater adhesion of chitosan on the fiber's surface. Finally, the color strength of samples dyed with folium was tested through fiber optic reflectance spectroscopy, and the folium absorbance peaks were still detected after fabric washing. It is thus shown how an ancient, traditional raw matter has become relevant for developing new modern technologies. [ABSTRACT FROM AUTHOR]

Cobalt manganese oxide (CoMn2O4) material production and characterization are presented in this work in preparation for their possible application in supercapacitors. The synthesis process used is a top‐down solid‐state strategy that is both economical and environmentally benign. After 500 °C post‐calcination, phase purity is verified by X‐ray diffraction (XRD) analysis. In the CoMn2O4, significant metal oxide vibrational modes are shown by Fourier transform infrared spectroscopy (FTIR). Raman spectroscopy is used to characterize structure, through elemental color mapping, energy‐dispersive X‐ray spectroscopy (EDX), and field emission scanning electron microscopy (FE‐SEM), researchers analyze morphological characteristics. Cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) experiments distinctly demonstrate that plasma treatment enhances the material properties including intensity, bending vibrations, morphology, and capacitance. After being exposed to air plasma, the resultant CoMn2O4 shows a notable capacitance of 961 F/g at 0.5 mA/g in a 2 M KOH electrolyte. These findings together suggest that CoMn2O4 has potential as an electrode material for supercapacitor research. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the surface changes and shear bond strength between a resin composite and two zirconia ceramics subjected to sandblasting and forming gas (5% H2 in N2) plasma surface treatment. Two types of zirconia ceramic specimens (3Y-TZP and (Y,Nb)-TZP) were divided into groups based on the following surface treatment methods: polishing (Control), sandblasting (SB), sandblasting and plasma (SB-P), and plasma treatment (P). Subsequently, chemical surface modification was performed using Clearfil SE Bond (Kuraray, Tokyo, Japan), and the Filtek Z-250 (3M, Maplewood, MN, USA) resin composite was applied. Shear bond strengths (SBS) and surface characteristics were determined. Plasma treatment was effective in increasing the wettability. For SBS, there were significant differences among the groups, and the (Y,Nb)-TZP and SB-P groups showed the highest bond strength. Similarly, for the 3Y-TZP specimens, the shear bond strength increased with both plasma and sandblasting treatments, although no statistically significant change was observed. In the P group, both (Y,Nb)-TZP and 3Y-TZP showed a significant decrease in shear bond strength with the resin composite compared to the control group. [ABSTRACT FROM AUTHOR]

Recent studies have explored surface treatments, such as increasing the hydrophilicity of implant fixtures, to enhance the osseointegration of implants. This prospective clinical study aimed to assess the clinical stability and efficacy of plasma treatment applied to implants with sandblast−acid etching (SLA) surfaces before placement. Twenty-eight patients requiring implant placement provided consent and were assigned randomly to either the SLA group without plasma treatment or the SLA/plasma group with plasma treatment. Recall checks were conducted one and three months after the first-stage surgery, followed by a second surgery at four months. Although no significant differences in buccal bone defects or implant stability were observed between the groups, the SLA/plasma group showed significant increases in marginal bone changes on the mesial and distal sides, as assessed using periapical radiographs. This study underscores the potential of pre-implantation plasma treatment to enhance bone regeneration around implants. [ABSTRACT FROM AUTHOR]

Wax warm additives are widely used in asphalt mixture production due to their energy savings and low cost. However, the compatibility problem between waxes and asphalt binders leads to wax precipitation and asphalt low-temperature cracking. Plasma treatment technology can modify the surface of waxes. In this study, plasma technology was used to modify Fischer Tropsch (FT) wax surfaces, linear aliphatic hydrocarbon wax, and two plastic cracking waxes. The effects of waxes on the high-temperature performance, fatigue performance, low-temperature physical hardening, and wax precipitation temperature of asphalt binders were evaluated by the multistress creep recovery (MSCR) test, linear amplitude sweep (LAS) test, extended bending beam rheometer (ExBBR) test, and dynamic shear rheometer (DSR) viscosity test. In addition, the effect of plasma treatment on waxes in terms of low-temperature physical hardening and wax precipitation temperature was explored. The results showed that the effect of waxes on the high-temperature properties of asphalt binders was related to wax type, dosage, and stress level. Within the allowable dosage range, waxes improve the fatigue properties of asphalt binders. After plasma treatment, the surface roughness and activity of waxes were increased, resulting in the alleviation of physical hardening of waxed asphalt binders and a decrease in wax precipitation temperature. Among them, plastic cracking waxes were more sensitive to the plasma treatment technique. [ABSTRACT FROM AUTHOR]

One-dimensional lithium-ion transport channels in lithium iron phosphate (LFP) used as a cathode in lithium-ion batteries (LIBs) result in low electrical conductivity and reduced electrochemical performance. To overcome this limitation, three-dimensional plasma-treated reduced graphene oxide (rGO) was synthesized in this study and used as an additive for LFP in LIB cathodes. Graphene oxide was synthesized using Hummers' method, followed by mixing with LFP, lyophilization, and plasma treatment to obtain LFP@rGO. The plasma treatment achieved the highest degree of reduction and porosity in rGO, creating ion transfer channels. The structure of LFP@rGO was verified through scanning electron microscopy (SEM) analysis, which demonstrated that incorporating 10.0 wt% of rGO into LFP resulted in successful coverage by the rGO layer, forming LFP@rGO-10. In half-cell tests, LFP@rGO-10 exhibited a specific capacity of 142.7 mAh g−1 at the 1.0 C-rate, which is higher than that of LFP. The full-cell exhibited 86.8% capacity retention after 200 cycles, demonstrating the effectiveness of rGO in enhancing the performance of LFP as an LIB cathode material. The outstanding efficiency and performance of the LFP@rGO-10//graphite cell highlight the promising potential of rGO-modified LFP as a cathode material for high-performance LIBs, providing both increased capacity and stability. [ABSTRACT FROM AUTHOR]

The practical deployment of rechargeable aqueous zinc‐ion batteries (RAZBs) in the scaled power system suffers from unregulated Zn dendrite growth as well as parasitic reactions at the zinc foil/aqueous electrolyte interface, leading to insufficient zinc utilization and severe electrode corrosion. Herein, a novel crown ether additive is developed, with tailored molecular engineering, to stepwise regulate the Zn2+ solvation network and interfacial chemistry of Zn metal anode. The designed crown ether (C5SeCN), featuring zincophilic cyano group and hydrophobic selenium, efficiently reconstructs the solvation sheath of Zn ions at the 0.3 wt.% dose amount. Additionally, the ozone plasma treatment tethers the O2‐ groups onto the thin‐layer zinc foil, which thus binds Se atoms of the C5SeCN to the Zn anode. The Zn||Zn symmetric cells exhibit a lifespan of over 4500 h at 1 mA cm−2 and high current density endurance of up to 10 mA cm−2. Moreover, the 2 mAh cm−2 Zn||V2O5 full cell model, at the low N/P ratio of 2.8 with a lean electrolyte (E/C ratio = 10 µL mAh−1), enables robust cycling endurance at 2 A g⁻¹ for 300 cycles. This study unravels the interfacial design rationales for maximizing zinc utilization and highlights the commercial potential of crown ether additives for RAZBs development. [ABSTRACT FROM AUTHOR]

This study aims to characterize ramie-low melt polyester nonwoven fabrics treated with low-temperature plasma and to analyze 3-D images based on object-depth mapping (ODM) using the MATLAB® R2022a software. We examined the low-temperature plasma treatment of nonwoven ramie fabrics using a plasma generator with 30 kV output power, six-minute treatment times, and a 4.5 cm distance between electrodes. The fabric's chemical properties and surface topography were investigated using scanning electron microscopy (SEM) and infrared spectroscopy (FTIR). An analysis of the SEM images was performed using a statistical approach and image processing to determine the level of surface roughness. FTIR analysis revealed that fabrics exposed for six minutes differed from those that were not. Our findings indicated that plasma treatment caused the following: 1) Ramie fabrics to become more hydrophilic, as shown by their increased T% in the FTIR of hydrophilic functional groups such as hydroxyl (O-H), carboxyl (-COOH), and carbonyl (C=O); 2) A higher surface roughness was observed in nonwoven fabric during SEM testing and image processing; 3) Plasma treatment of fabrics resulted in a higher coefficient of variation (CV) than untreated fabrics; 4) Nonwoven fabric mass reduction. Based on this study, we found the relationship between plasma-treated ramie fabric and textiles in biomechanics. Plasma treatment reduced the mass of ramie fabric by 0.11 %, according to our findings. We found that the greater the mass reduction, the greater the surface roughness value. The novelty of this study is the use of 3-D images based on object-depth mapping (ODM) using the MATLAB® R2022a software in SEM to observe surface roughness to the physical properties of ramie fabric for the first time. [ABSTRACT FROM AUTHOR]

In this study, we investigate the impact of O2 plasma treatment on the performance of Al/TaOX/Al-based resistive random-access memory (RRAM) devices, focusing on applications in neuromorphic systems. Comparative analysis using scanning electron microscopy and X-ray photoelectron spectroscopy confirmed the differences in chemical composition between O2-plasma-treated and untreated RRAM cells. Direct-current measurements showed that O2-plasma-treated RRAM cells exhibited significant improvements over untreated RRAM cells, including higher on/off ratios, improved uniformity and distribution, longer retention times, and enhanced durability. The conduction mechanism is investigated by current–voltage (I–V) curve fitting. In addition, paired-pulse facilitation (PPF) is observed using partial short-term memory. Furthermore, 3- and 4-bit weight tuning with auto-pulse-tuning algorithms was achieved to improve the controllability of the synapse weight for the neuromorphic system, maintaining retention times exceeding 103 s in the multiple states. Neuromorphic simulation with an MNIST dataset is conducted to evaluate the synaptic device. [ABSTRACT FROM AUTHOR]

Polyimide (PI) surfaces coated with and without boron nitride nanotubes (BNNTs) were treated using an atmospheric‐pressure cold plasma in open air. This treatment increased the surface wettability of the PI, measured by a decrease in water contact angle from 68° to 16°, resulting in a more uniform BNNT coating and improved surface adhesion. The plasma treatment of the BNNT‐coated PI surfaces also effectively removed residual polymer surfactants used for BNNT dispersion in water, without causing any thermal damage due to the low plasma and PI's surface temperatures of 350 and 300 K, respectively. The reactive oxygen species in the plasma, such as hydroxyl molecules and oxygen atoms, played an important role in these processes. Atmospheric‐pressure plasma can be employed in various applications in which thermally weak polymer‐based substrates are coated with BNNTs. [ABSTRACT FROM AUTHOR]

Ion exchange membranes were fabricated using a phase inversion technique based on polyvinyl chloride nanocomposites. Subsequently, electrodialysis membranes were modified by the addition of [SiO2-co-Ag] nanoparticles using magnetron sputtering. The impact of varying concentrations of [SiO2-co-Ag] nanoparticles on the performance of mixed-matrix poly (vinyl chloride)-based nanoparticle cation exchange membranes was studied. Various techniques, including scanning electron microscopy (SEM), atomic force microscopy (AFM), and scanning optical microscopy (SOM) confirmed the presence of nanoparticles in the structure of membranes. The SEM images showed that the addition of SiO2-co-Ag nanoparticles resulted in a more compact structure for the modified membranes. The SOM images show that the fabricated membranes had a uniform surface and uniform distribution of SiO2-Ag in the membrane matrix. The AFM images revealed that the modified membranes had a rough surface at high additive concentrations (4.0% wt.) and cross-sectional SEM images confirmed that the addition of nanoparticles created cracks and cavities in the membrane structure. The hydrophilicity of silica and silver nanoparticles increased the surface hydrophilicity of the modified membranes. The membrane potential, permselectivity, and transport number showed fluctuations, decreasing initially with the use of SiO2-co-Ag nanoparticles up to a concentration of 1.0% wt and then increasing with an increase in the concentration of nanoparticles to 2.0% wt before declining again for a concentration of 4.0% wt. The flux and ionic permeability were promoted by the addition of SiO2-co-Ag up to 1.0% wt, but after that, they showed a decreasing trend with an increase in the concentration of nanoparticles. The areal electrical resistance of the prepared membrane dramatically declined with an increase in the concentration of SiO2-Ag. Importantly, the application of these membranes was in electrodialysis, and the use of also enhanced the mechanical resistance of the membranes. Furthermore, the fabricated membranes exhibited a good ability to remove E. coli from water. Notably, the modified membrane with a 1.0% wt concentration of SiO2-co-Ag nanoparticles demonstrated greater performance in removing E. coli. [ABSTRACT FROM AUTHOR]

For the improvement of asphalt-based waterproofing membrane bonding effect on the concrete surface,this paper systematically studied the changes in surface functional groups after surface oxygen,nitrogen and air plasma treatment and molecu lar grafting of waterproofing membranes. The surface functional groups established through plasma treatment are further modified with polyhydroxy or silyl functional molecules,such as silane reagents,dopamineand lignin,to optimize molecular branching and concrete bonding capacity.Through the contact angle measurement,infrared spectroscopy,XPS and other means,it found that the plasma treatment of modified asphalt-based waterproofing membrane surface shows obvious hydrophilicity changes and the corre sponding chemical functional group absorption peaks,proving the realization of the plasma treatment of modified surface groups and the success of the branching molecules. It can enhance the bonding effect between waterproof membrane and concrete. [ABSTRACT FROM AUTHOR]

The Plasma Electrolytic Oxidation (PEO) process was investigated to enhance the adhesion of AA2024-O aluminum alloy with a polyetherimide (PEI) matrix composite, using oxy-fuel welding (OFW). A Central Composite Design (CCD) statistical model was used to optimize three independent parameters in PEO: immersion time (s), duty cycle (%), and electrolyte concentration (Na2B4O7·10H2O), aiming to achieve a maximum value of shear strength of the hybrid joint (in MPa). The hybrid joint without PEO treatment presented a resistance of 2.2 MPa while the best condition presented a resistance of 9.5 MPa, resulting in a value 4× higher than the untreated material, due to the characteristics of the coating, which presented a more hydrophilic surface, allowing better mechanical interlocking with the polymer matrix and resulting in mixed-mode failure (adhesive, cohesive, and light fiber). In addition to improving adhesion, the PEO treatment provided better corrosion resistance to the alloy, forming an inert aluminum oxide (Al2O3) coating, with an improvement of approximately 99.84% compared to the untreated alloy. The statistical design covers about 77.15% of the total variability of the PEO + welding process, with independent factors influencing around 48.4% of the variability. [ABSTRACT FROM AUTHOR]

Polystyrene (PS) finds diverse applications across various fields, often necessitating a hydrophilic PS surface. In this study, the PS films were prepared using PS–toluene solutions of 15, 20, and 25 mass percentage concentrations (% w/v). Here, the main focus is on the influence of concentration on the hydrophilization of the prepared PS thin films under atmospheric pressure air dielectric barrier discharge plasma treatment. The contact angle, surface energy measurements, atomic force microscopy, and Fourier‐transform infrared spectroscopy analysis were conducted to evaluate the PS surface properties. Our results demonstrate, for the first time, the significant role of concentration in altering surface properties; the lower concentration of PS films leads to the most hydrophilic surface. Fourier‐transform infrared spectroscopy analysis confirms an increase in the OH functional group on the PS surface. atomic force microscopy analysis reveals needle‐shaped surface morphology, increased roughness and an expanded effective surface area. Surface energy analysis confirms an increase in the polar sector of surface energy. Overall, the findings from this research underscore the increase in film hydrophilicity with a decrease in PS–toluene concentration. Highlights: Polystyrene (PS)–toluene solutions with different concentrations were prepared.PS–toluene films were spin‐coated and were been treated with dielectric barrier discharge plasma.The contact angle, surface energy measurements, atomic force microscopy, and Fourier‐transform infrared spectroscopy analysis were conducted.PS films with lower concentration have more impact from plasma treatment.Concentration, impact the hydrophilicity and roughness of treated PS films. [ABSTRACT FROM AUTHOR]

Surface modification via plasma treatment is useful in improving textile-based wound dressing functionality. This study was conducted to optimise the nitrogen plasma exposure time and its effect on the cotton surface (CS) properties at a constant nitrogen flow rate of 20 sccm for 5 to 30 min. The optimisation was done by analysing the alteration in morphology, functional group composition, crystallinity phase, electrokinetic charge, and colour of CS as subjected to nitrogen plasma. CS experienced an etching effect due to the presence of microcracks on its surface, with its electrokinetic charge becoming less negative, ranging from -5.51 to -1.32 mV. Then, the nitrogen functional group was detected on CS ranging from 2.9% to 4.5%, with its whiteness index reduced to 8.67% compared to the pristine cotton. As a result, 20 min was selected as the optimum exposure time for surface treatment because the exposure time of 30 min showed an early sign of degradation, which reduced its crystallinity index by 11.1%. Apparently, activated CS experienced slight changes in its molecular structure without affecting its bulk properties. Thus, the plasma-modified CS is useful in creating a biocompatible wound dressing that can anchor therapeutic biomaterial and improve healing.

Abstract Background Gutta-percha (GP) combined with an endodontic sealer is still the core material most widely used for tridimensional obturation. The sealer acts as a bonding agent between the GP and the root dentinal walls. However, one of the main drawbacks of GP core material is the lack of adhesiveness to the sealer. ZnO thin films have many remarkable features due to their considerable bond strength, good optical quality, and excellent piezoelectric, antibacterial, and antifungal properties, offering many potential applications in various fields. This study aimed to explore the influence of GP surface’s functionalization with a nanostructured ZnO thin film on its adhesiveness to endodontic sealers. Methods Conventional GP samples were divided randomly into three groups: (a) Untreated GP (control); (b) GP treated with argon plasma (PT); (c) Functionalized GP (PT followed by ZnO thin film deposition). GP’s surface functionalization encompassed a multi-step process. First, a low-pressure argon PT was applied to modify the GP surface, followed by a ZnO thin film deposition via magnetron sputtering. The surface morphology was assessed using SEM and water contact angle analysis. Further comprehensive testing included tensile bond strength assessment evaluating Endoresin and AH Plus Bioceramic sealers’ adhesion to GP. ANOVA procedures were used for data statistical analysis. Results The ZnO thin film reproduced the underlying surface topography produced by PT. ZnO thin film deposition decreased the water contact angle compared to the control (p

In recent years, the range of silicon-containing steels subjected to hot galvanizing has been expanding. Alloying of steel with 0.5–1 % of silicon leads to the formation of a zinc coating of great thickness with a matte or multi-colored surface. This is associated with the changes in phase reactions between iron and zinc in the Fe–Zn–Si system. The development of ways to neutralize the negative influence of silicon on the formation of zinc coating is an urgent task. The purpose of the work is to study the influence of preliminary plasma cutting and plasma surface hardening of 09G2S (S355J2) steel on the thickness and structure of zinc coating formed on treated surfaces. It was found that after plasma cutting, the structure of the surface layer of steel is martensite, and after plasma surface hardening, it is martensite and ferrite. Analysis of the change in microhardness from the steel surface to the middle showed that the hardened layer depth is 400 μm. A zinc coating consisting of a δ-phase and a ζ-phase is formed on the surface of the steel without pretreatment. On the surface of the steel after plasma treatment, a zinc coating is formed characteristic of low-silicon steels and consisting of the δ-phase, ζ-phase, and η-phase. It was found that the thickness of the zinc coating on the surface after plasma cutting is two times less than on the untreated surface, and the reduction in the coating thickness occurs due to a decrease in the ζ-phase thickness. A hypothesis was suggested that the martensite formation on the steel surface leads to the disappearance of the ordered FeSi phase and changes the phase equilibrium in the Fe–Zn–Si system. Consequently, preliminary plasma treatment of the steel surface allows controlling the structure and thickness of the resulting zinc coating and is therefore recommended for introduction into the hot galvanizing process of silicon-containing steels.

Nonwoven fabrics are used in many industries, and surface treatment by plasma can significantly change their physical and mechanical properties by changing the surface chemistry and morphology. In this paper, oxygen/argon plasma has been applied to the spunbond nonwoven fabrics to predict the obtained properties. Therefore, by using the central composite design and considering 4 independent factors including the fabric weight, fabric direction, plasma treatment duration and oxygen ratio, 51 various samples were prepared and their bending rigidity and formability were measured. SEM images showed that the surface roughness increases due to the plasma treatment. Statistical analysis revealed that all the mentioned independent factors have a significant effect on the measured parameters directly or reciprocally. Also, the use of a neural network model with two hidden layers optimized with a method according to the genetic algorithm can predict the bending rigidity and formability based on the independent factors with errors of less than 7% and 9%, respectively. The errors resulting from the surface response method for the same parameters with the same order are about 19% and 17%. The introduced method can be used as a tool to help researchers in the field of mechanical properties.

A new two-step method for developing a nanocomposite of polypropylene (PP) decorated with photocatalytically active TiO2 nanoparticles (nTiO2) is proposed. This method involves the low-temperature plasma functionalization of polypropylene followed by the ultrasound-assisted anchoring of nTiO2. The nanoparticles, polymeric substrate, and resultant nanocomposite were thoroughly characterized using nanoparticle tracking analysis (NTA), microscopic observations (SEM, TEM, and EDX), spectroscopic investigations (XPS and FTIR), thermogravimetric analysis (TG/DTA), and water contact angle (WCA) measurements. The photocatalytic activity of the nanocomposites was evaluated through the degradation of methyl orange. The individual TiO2 nanoparticles ranged from 2 to 6 nm in size. The oxygen plasma treatment of PP generated surface functional groups (mainly -OH and -C=O), transforming the surface from hydrophobic to hydrophilic, which facilitated the efficient deposition of nTiO2. Optimized plasma treatment and sonochemical deposition parameters resulted in an active photocatalytic nTiO2/PP system, degrading 80% of the methyl orange under UVA irradiation in 200 min. The proposed approach is considered versatile for the functionalization of polymeric materials with photoactive nanoparticles and, in a broader perspective, can be utilized for the fabrication of self-cleaning surfaces. [ABSTRACT FROM AUTHOR]

The efficient removal of low‐concentration endocrine disruptors is crucial for the protection of the aquatic environment. In this study, porous polymer adsorbent materials were modified by nanosecond pulsed discharge plasma to achieve efficient adsorption of low‐concentration bisphenol A (BPA). The removal efficiency of BPA reached 99% after 10 min of plasma modification at a pulse peak voltage of 28 kV, which increased by 25.8% compared to the raw materials. This enhancement was attributed to the increase of active sites and oxygen‐containing functional groups. The adsorption behaviors of the porous polymer materials were primarily dominated by monolayer chemisorption. Subsequently, comparative experiments further verified the high‐efficiency adsorption performance of porous polymer materials after plasma treatment. [ABSTRACT FROM AUTHOR]

The utilization of plasma treatment as a technique for fading the colours on textiles is an environmentally friendly approach. However, the challenge lies in the continuous adjustment of its parameters to attain desired fading colour effects. This is due to the unclear mechanism causing changes in fading effect as a result of alterations in plasma treatment parameters. This research endeavours to predict the alteration of fading effect after plasma treatment of cotton fabrics under varying parameters through the development of a prediction system based on a Bayesian Regulated Neural Network (BRNN) with 10-fold cross-validation. Through a modular approach, the inputs for the training of BRNN models include initial values of plasma treatment parameters such as colour depth, air (oxygen) concentration, water content, treatment time, and one of the CIE L*a*b* values and K/S values corresponding to cotton materials. The outputs, trained individually by four independent BRNN models, are the final values of four colour variables: CIE L*, CIE a*, CIE b* and K/S. The models were trained and validated through the Bayesian Regularization Algorithm and 10-fold cross-validation on 192 data sets, yielding fitted coefficients of determination R2 of 0.9956, 0.9976, 0.9980 and 0.9687, respectively. Approximately 87.5% − 91.67% of predicted colours were within the range of imperceptible or acceptable differences from actual colours. Hence, the developed artificial intelligence system can aid textile finishers in adjusting the plasma colour fading machine's parameter settings and selected recipes, thus enhancing efficiency and reducing cost and trial time. [ABSTRACT FROM AUTHOR]

[Display omitted] • Contact angles of anode and cathode materials are modified using plasma modification. • Interactions between plasma parameters are evaluated by Box-Behnken design. • Plasma treatment enhances flotation separation selectivity of electrode materials. • Flotation of anode and cathode materials obeys to the first order-kinetic model. • The contact angle increase of anode materials plays a major role in plasma treatment. The recycling of spent lithium-ion batteries (LIBs) can not only reduce the potential harm caused by solid waste piles to the local environment but also provide raw materials for manufacturing new batteries. Flotation is an alternative approach to achieve the selective separation of cathode and anode active materials from spent LIBs. However, the presence of organic binder on the surface of hydrophilic lithium transition-metal oxides results in losses of cathode materials in the froth phase. In this study, plasma treatment was utilized to remove organic layers from cathode and anode active materials. Firstly, the correlations between plasma treatment parameters (e.g., input power, air flowrate, and treatment time) were explored and the contact angles of cathode and anode active materials were investigated by the response surface methodology. Secondly, differences in the flotation recoveries of cathode and anode active materials were enhanced with plasma modification prior to flotation, which is consistent with the contact angle measurement. Finally, the plasma-modification mechanisms of hydrophobicity of cathode and anode active materials were discussed according to Fourier Transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The proposed method could be a promising tool to enhance the flotation separation efficiency of cathode and anode active materials for the recycling of spent LIBs. [ABSTRACT FROM AUTHOR]

The chemical bath deposition (CBD) process enables the deposition of ZnO nanowires (NWs) on various substrates with customizable morphology. However, the hydrogen-rich CBD environment introduces numerous hydrogen-related defects, unintentionally doping the ZnO NWs and increasing their electrical conductivity. The oxygen-based plasma treatment can modify the nature and amount of these defects, potentially tailoring the ZnO NW properties for specific applications. This study examines the impact of the average ion energy on the formation of oxygen vacancies (VO) and hydrogen-related defects in ZnO NWs exposed to low-pressure oxygen plasma. Using X-ray photoelectron spectroscopy (XPS), 5 K cathodoluminescence (5K CL), and Raman spectroscopy, a comprehensive understanding of the effect of the oxygen ion energy on the formation of defects and defect complexes was established. A series of associative and dissociative reactions indicated that controlling plasma process parameters, particularly ion energy, is crucial. The XPS data suggested that increasing the ion energy could enhance Fermi level pinning by increasing the amount of VO and favoring the hydroxyl group adsorption, expanding the depletion region of charge carriers. The 5K CL and Raman spectroscopy further demonstrated the potential to adjust the ZnO NW physical properties by varying the oxygen ion energy, affecting various donor- and acceptor-type defect complexes. This study highlights the ability to tune the ZnO NW properties at low temperature by modifying plasma process parameters, offering new possibilities for a wide variety of nanoscale engineering devices fabricated on flexible and/or transparent substrates. [ABSTRACT FROM AUTHOR]

Oxygen vacancies and heteroatom doping play important role in oxygen reduction activity of metal oxides. Developing efficient modification method is one of the key issues in catalysts research. Room temperature plasma treatment, with the advantages of mild working conditions, no emissions and high efficiency, is a new catalyst modification method developed in recent years. In this work, hydrothermal synthesized α -MnO2 nanorods are treated in NH3 plasma at room temperature. In the reducing atmosphere, oxygen vacancies and N doping are achieved simultaneously on the surface. The NH3 plasma etched MnO2 demonstrate a significant enhanced oxygen reduction activity with half-wave potential of 0.84 V, limiting current density of 6.32 mA cm−2 and transferred electrons number of 3.9. The Mg–air battery with N-MnO2 display a maximum power density of 76.3 mW cm−2 as well as stable discharge performance. This work provides new ideas for preparing efficient and cost-effective method to boost the catalysts activity. [ABSTRACT FROM AUTHOR]

The hydrophobic nature of synthetic polymers poses a substantial barrier since it limits cell-seeding and proliferation scaffold performance. To overcome this challenge, the present research attempts to employ in-situ UV electrospinning and plasma surface modification techniques to fabricate a three-dimensional PAN/PVA-gelatin scaffold. The proposed scaffold holds great potential in mitigating hydrophobicity limitations, thereby facilitating enhanced cell adhesion and proliferation. The SEM results indicated that exposure to UV irradiation resulted in the formation of wavy shapes in the PAN microstructures and crosslinking between fibers within the scaffold. Moreover, plasma treatment induced the formation of pores on the PAN surface, with an average diameter of 43 µm, corresponding to the size range of mouse fibroblast cells. Furthermore, the plasma treatment provided roughness augmentation of the scaffold surface, which played a crucial role in enhancing cell adhesion and elongation on the modified scaffold surface. Comparatively, the plasma-modified scaffolds exhibited a higher proportion of viable cells than the unmodified scaffolds (p < 0.05). Moreover, the implementation of perforations in the PAN layer via plasma treatment reduced the number of necrosis cells in comparison to the other samples. In contrast, the unmodified scaffold showed a higher percentage of apoptosis cells (p < 0.05). [ABSTRACT FROM AUTHOR]

Surface modification via plasma treatment is useful in improving textilebased wound dressing functionality. This study was conducted to optimise the nitrogen plasma exposure time and its effect on the cotton surface (CS) properties at a constant nitrogen flow rate of 20 sccm for 5 to 30 min. The optimisation was done by analysing the alteration in morphology, functional group composition, crystallinity phase, electrokinetic potential, and colour of CS as subjected to nitrogen plasma. CS experienced an etching effect due to the presence of microcracks on its surface, with its electrokinetic potential becoming less negative, ranging from -5.51 to -8.05 mV. Then, the nitrogen functional group was detected on CS ranging from 2.9% to 4.5%, with its whiteness index reduced to 8.67% compared to the pristine cotton. As a result, 20 min was selected as the optimum exposure time for surface treatment. An exposure time of 30 min showed an early sign of degradation, which reduced its crystallinity index by 11.1%. Apparently, the CS is activated as exposed to the nitrogen plasma and experiences slight changes in its molecular structure without affecting its bulk properties. [ABSTRACT FROM AUTHOR]

The paper deals with a novel method for the edge preparation of cutting tools using an advanced approach. Cemented carbide cutting inserts were used as a sample in the experiment, and were prepared using plasma discharges in electrolyte. This technique is an environmentally-friendlier method in contrast to electropolishing treatment. The experiment aimed to determine the influence of process parameters of plasma treatment on the material removal rate and cutting edge radius size. In the experiment, concentration of electrolyte, voltage between electrodes, temperature of electrolyte, and operating time were varied. The material removal rate and cutting edge radius size increased faster with the decreasing concentration of electrolyte, decreasing voltage, and decreasing temperature of electrolyte. The material removal percentage increase was 155 percent, and 57 percent for cutting edge radius size during the 10 seconds of operation time in the specified range of process parameters. This change can be achieved by setting various process parameters. The results of the experiment proved that plasma treatment can control the forming of cutting edge radii. Cutting edge preparation using plasma discharges in electrolyte takes only a few seconds, depending on the cutting edge radius sizes. [ABSTRACT FROM AUTHOR]

Conventional wound treatment options provide a barrier against exogenous microbial penetration but cannot simultaneously provide an antibacterial characteristic and promote healing. However, bioactive dressings can accelerate wound healing and have an antibacterial effect in addition to being able to cover and protect lesions. In this study, double‐layer thermoplastic polyurethane (TPU)‐gelatin fibrous dressings that mimic the epidermis and dermis layers of the skin were fabricated via electrospinning technique. As a bioactive agent, Hypericum perforatum oil (HPO) was utilized to impart antibacterial and therapeutic properties to the dressings. Tannic acid was also used in fiber mat formulations as a cross‐linking agent. Oxygen plasma treatment was applied as a surface activation technique to improve adhesion of TPU and gelation layers. The fiber structure of the mats was revealed by a scanning electron microscopy (SEM) study. Fourier transform infrared (FTIR) spectroscopy was used to demonstrate HPO loading onto the mats. The water vapor transmission rate (WVTR) and fluid absorbency of the mats were compared with some commercial dressings. According to these results, it can be suggested that the mats can be used for moderate to high exudative wounds. All dressings, even the control sample showed antibacterial features against both Staphylococcus aureus and Escherichia coli bacteria due to the tannic acid. In vitro wound healing assays were carried out on the plasma‐treated sample and it was observed that the sample did not negatively affect the migration and proliferation abilities of the cells which are necessary for wound healing. Overall results indicated that the plasma‐treated fibrous mat would be a good candidate as a wound dressing material having an antibacterial character. [ABSTRACT FROM AUTHOR]

Plasma treatment of wood surfaces has shown significant effects, but different excitation methods used for different species of wood generally result in varied characteristics of wood surfaces. Secondly, plasma modification greatly enhances the absorption of liquids by wood, but the relationship between liquid absorption and surface wettability is rarely studied. Limited detailed investigation of the modification effects and mechanisms has hindered the large-scale applications of plasma treatment in the wood industry. In this study, two typical plasmas, radio frequency (RF) plasma and gliding arc discharge (GAD) plasma, were employed to treat three species of wood: poplar, black walnut, and sapele. By focusing on changes in the contact angle of the wood surface, an exponential equation fitting method is used to determine the measurement time for contact angles. The research identified that factors contributing to the decrease in contact angle after plasma modification include not only the increase in surface energy but also liquid absorption. SEM and XPS analyses demonstrate that plasma etching accelerated liquid absorption by modifying the surface topography, while the increase in surface energy was due to the addition of oxygen-containing groups. High-valence C=O and O-C=O groups serve as indicators of plasma-induced surface chemical reactions. RF modification primarily features surface etching, whereas GAD significantly increases the active surface groups. Thus, different plasmas, due to their distinct excitation modes, produce diverse modification effects on wood. Considering the various physical and chemical properties of plasma-modified wood surfaces, recommendations for adhesive use on plasma-modified wood are provided. [ABSTRACT FROM AUTHOR]

Background: Gutta-percha (GP) combined with an endodontic sealer is still the core material most widely used for tridimensional obturation. The sealer acts as a bonding agent between the GP and the root dentinal walls. However, one of the main drawbacks of GP core material is the lack of adhesiveness to the sealer. ZnO thin films have many remarkable features due to their considerable bond strength, good optical quality, and excellent piezoelectric, antibacterial, and antifungal properties, offering many potential applications in various fields. This study aimed to explore the influence of GP surface's functionalization with a nanostructured ZnO thin film on its adhesiveness to endodontic sealers. Methods: Conventional GP samples were divided randomly into three groups: (a) Untreated GP (control); (b) GP treated with argon plasma (PT); (c) Functionalized GP (PT followed by ZnO thin film deposition). GP's surface functionalization encompassed a multi-step process. First, a low-pressure argon PT was applied to modify the GP surface, followed by a ZnO thin film deposition via magnetron sputtering. The surface morphology was assessed using SEM and water contact angle analysis. Further comprehensive testing included tensile bond strength assessment evaluating Endoresin and AH Plus Bioceramic sealers' adhesion to GP. ANOVA procedures were used for data statistical analysis. Results: The ZnO thin film reproduced the underlying surface topography produced by PT. ZnO thin film deposition decreased the water contact angle compared to the control (p < 0.001). Endoresin showed a statistically higher mean bond strength value than AH Plus Bioceramic (p < 0.001). There was a statistically significant difference between the control and the ZnO-functionalized GP (p = 0.006), with the latter presenting the highest mean bond strength value. Conclusions: The deposition of a nanostructured ZnO thin film on GP surface induced a shift towards hydrophilicity and an increased GP's adhesion to Endoresin and AH Bioceramic sealers. [ABSTRACT FROM AUTHOR]

In this study, the effect of atmospheric hydrogen plasma treatment on the in-plane conductivity of solution-processed zinc oxide (ZnO) in various environments is reported. The hydrogen-plasma-treated and untreated ZnO films exhibited ohmic behavior with room-temperature in-plane conductivity in a vacuum. When the untreated ZnO film was exposed to a dry oxygen environment, the conductivity rapidly decreased, and an oscillating current was observed. In certain cases, the thin film reversibly 'switched' between the high- and low-conductivity states. In contrast, the conductivity of the hydrogen-plasma-treated ZnO film remained nearly constant under different ambient conditions. We infer that hydrogen acts as a shallow donor, increasing the carrier concentration and generating oxygen vacancies by eliminating the surface contamination layer. Hence, atmospheric hydrogen plasma treatment could play a crucial role in stabilizing the conductivity of ZnO films. [ABSTRACT FROM AUTHOR]

This study investigates the low-temperature hydrogen plasma treatment approach for the improvement of hydrogen generation through waste aluminum (Al) reactions with water and electricity generation via proton-exchange membrane fuel cell (PEM FC). Waste Al scraps were subjected to ball milling and treated using two different low-temperature plasma regimes: Diode and magnetron-initiated plasma treatment. Hydrolysis experiments were conducted using powders with different treatments, varying molarities, and reaction temperatures to assess hydrogen generation, reaction kinetics, and activation energy. The results indicate that magnetron-initiated plasma treatment significantly enhances the hydrolysis reaction kinetics compared to untreated powders or those treated with diode-generated plasma. Analysis of chemical bonds revealed that magnetron-initiated hydrogen plasma treatment takes advantage by promoting a dual procedure: Surface cleaning and Al nanocluster deposition on top of Al powders. Moreover, it was modeled that such H2 plasma could penetrate up to 150 Å depth. Meanwhile, electricity generation tests demonstrate that only 0.2 g of treated Al powder can generate approximately 1 V for over 300 s under a constant 2.5 Ω load and 1.5 V for 2700 s with a spinning fan. [ABSTRACT FROM AUTHOR]

Wet beneficiation is a primary process employed by mining companies for iron ore concentration. The moisture content in the ore is a result of this beneficiation process, in addition to inherent moisture within the mineral composition. The moisture content of iron ore is a crucial parameter that requires effective control to ensure safe handling and transportation operations. Surface plasma treatment of iron ore has been investigated as a method to enhance the hydrophobicity of ore particles, thereby reducing residual moisture and water reabsorption by the particles. The samples underwent treatment using argon plasma and cold hexamethyldisiloxane (HMDSO) plasma, leading to the formation of a thin, silicon-rich surface layer. The treatments were applied to both polished ore samples and fine powder samples. The plasma treatment resulted in a reduction in moisture content and water absorption. The reabsorption of water decreased to approximately 35% of the pretreatment values. Contact angle measurements demonstrated that all HMDSO-treated samples exhibited hydrophobic behavior, with contact angles ranging from 110° to 120°, while the untreated samples exhibited angles close to 0°. Furthermore, atomic force microscopy (AFM) topographic imaging revealed a granular structure in the thin films. [ABSTRACT FROM AUTHOR]

Magnesium batteries provide a promising alternative to traditional energy storage solutions due to their impressive energy density, potential safety features, and cost-effectiveness, making them highly suitable for large-scale applications. The solid state synthesis of MgCoSiO4 is reported in this work. The produced magnesium cobalt silicate nanoparticles are treated with 450 V of DC glow discharge plasma for 15 min of exposure time. The novel aspect of the MgCoSiO4 material generated in a solid state is highlighted in this research work. This material underwent plasma treatment, which changed its surface and improved its performance. Through testing and investigation, these modifications resulted in increased conductivity and overall electrode material efficiency, demonstrating the substantial influence of the treatment material functionality. It enhances the electrochemical characteristics by altering the surface energies, adhesion, and wettability. Thus the as prepared sample was made as the electrode material for further investigation. The sample's structural, morphological, and chemical makeup was examined using XRD, FTIR, FESEM and wettability. Owning to the exclusive sponge-like morphology and more porous air plasma treated MgCoSiO4 electrode displays higher specific capacitance of 1232 F/g than the pure 296 F/g which can also exhibit 89% of capacitance retention after 6000 cycles. These results suggests that the MgCoSiO4 electrode material treated with air plasma is appropriate for use in energy storage applications. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to compare the environmental impact, using Life Cycle Assessment, and the total cost of two hydrophobic fluorocarbon treatment methods: a novel plasma surface modification technique and a traditional pad-dry-curing treatment of fabric. These two techniques have been chosen as two alternatives, with the pad-dry curing being a traditional liquid-based treatment and the plasma treatment a novel gas-based treatment. Such a comparison is a novel effort and will provide to the relevant industrial stakeholders an indication about the sustainability and the financial viability of the plasma treatment technique in comparison to the current state-of-the-art.The Life Cycle Inventory for both techniques has been compiled based on experiments performed at the Technical Textiles Research Centre, using lab scale equipment. The environmental impact has been assessed using the Environmental Footprint 3.0 method and is expressed in micro ecopoints (μPt). The findings have revealed that for plasma treatment (duration of 5 min using 13 cm3/min of C2F6), the environmental footprint is 47% lower than the conventional pad-dry-curing (8.95 μPt per 10 g of treated cotton compared to 18.9 μPt) and the total treatment cost is 81% lower (£1.03 per 10 g of treated cotton compared to £5.47 using pad-dry-curing). The most significant contributor to the environmental performance of the plasma treatment is the electricity consumption, thus a minimization of the treatment time without losing the functionality of the process, and the subsequent operating expenses, will lead to the optimal plasma treatment conditions.

Abstract Background Melting corneal ulcers are a serious condition that affects a great number of animals and people around the world and it is characterised by a progressive weakening of the tissue leading to possible severe ophthalmic complications, such as visual impairment or blindness. This disease is routinely treated with medical therapy and keratoplasty, and recently also with alternative regenerative therapies, such as cross-linking, amniotic membrane transplant, and laser. Plasma medicine is another recent example of regenerative treatment that showed promising results in reducing the microbial load of corneal tissue together with maintaining its cellular vitality. Since the effect of helium plasma application on corneal mechanical viscoelasticity has not yet been investigated, the aim of this study is first to evaluate it on ex vivo porcine corneas for different exposition times and then to compare the results with previous data on cross-linking treatment. Results 94 ex vivo porcine corneas divided into 16 populations (healthy or injured, fresh or cultured and treated or not with plasma or cross-linking) were analysed. For each population, a biomechanical analysis was performed by uniaxial stress-relaxation tests, and a statistical analysis was carried out considering the characteristic mechanical parameters. In terms of equilibrium normalised stress, no statistically significant difference resulted when the healthy corneas were compared with lesioned plasma-treated ones, independently of treatment time, contrary to what was obtained about the cross-linking treated corneas which exhibited more intense relaxation phenomena. Conclusions In this study, the influence of the Helium plasma treatment was observed on the viscoelasticity of porcine corneas ex vivo, by restoring in lesioned tissue a degree of relaxation similar to the one of the native tissue, even after only 2 min of application. Therefore, the obtained results suggest that plasma treatment is a promising new regenerative ophthalmic therapy for melting corneal ulcers, laying the groundwork for further studies to correlate the mechanical findings with corneal histology and ultrastructural anatomy after plasma treatment.