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This study introduces a novel and efficient approach for synthesizing perovskite-type nanoparticles and advanced plasma surface activation to significantly improve the supercapacitor's performance. High-purity La 0.6 Ca 0.4 MnO 3 (LCMO) perovskite nanoparticles with a crystalline structure were synthesized using a facile coprecipitation technique, followed by an innovative low-pressure DC glow-discharge plasma treatment in an oxygen atmosphere. This plasma surface activation process enhances the surface properties of the nanoparticles and boosts their electrochemical performance, representing a transformative modification method for energy storage materials. Detailed analysis of the synthesized and surface-activated LCMO (SA@LCMO) nanoparticles revealed a well-defined cubic morphology with a remarkable surface area of 95 m2/g, as confirmed by TEM and BET analysis. The plasma-treated SA@LCMO electrodes demonstrated superior supercapacitor performance, delivering an impressive specific capacitance of 453 F/g at a current density of 1 A/g more than doubling the 225.8 F/g achieved by untreated LCMO electrodes. Additionally, the SA@LCMO electrodes exhibited exceptional cycle stability, retaining 87 % of their capacitance and achieving a coulombic efficiency of 95.2 % after 10,000 GCD cycles. The material also showed promising energy storage capabilities, with a maximum energy density of 3.92 Wh/kg at a power density of 170.6 W/kg. These results highlight the transformative impact of plasma surface activation on perovskite nanomaterials, positioning the SA@LCMO as a highly promising candidate for next-generation energy storage technologies with superior energy density, durability, and performance. This study introduces new avenues for surface engineering perovskite-based materials to create scalable high-performance energy storage devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Thin-film membranes of Pd-Ag and Pd-Cu alloys capable of releasing hydrogen in a wide temperature range have been developed. The surface activation of the membranes with a nanostructured coating made it possible to intensify hydrogen transport through Pd-containing membranes at low temperatures. This effect was achieved by accelerating limiting surface processes by increasing the active area of the membrane. Surface-activated membranes demonstrated the highest values of hydrogen flux over the entire temperature range, which reached up to 49.4 mmol s−1 m−2 for Pd-Ag membranes and up to 32.9 mmol s−1 m−2 for Pd-Cu membranes. Membranes modified with filiform nanoparticles demonstrated a hydrogen flux up to 12 times higher than that of membranes with a smooth surface. Based on the results obtained, a theoretical model of hydrogen transport through metal membranes was developed, taking into account the effect of the state of the membrane surface on hydrogen transport at low temperatures. This model makes it possible to predict hydrogen flows in the entire temperature range much more accurately compared to other existing models. The selectivity and stability of the developed membranes over a long period of operation have been confirmed. The study of the effect of the surface activation of Pd-based membranes on the intensification of hydrogen permeability has shown the success of the method developed, which in turn opens up wide opportunities for creating low-temperature, highly efficient membrane hydrogen filters based on palladium and other devices based on them. [ABSTRACT FROM AUTHOR]

The weakness of the fiber–matrix interface restricts the practical application of basalt fiber (BF) as a reinforcing material. In order to improve the interfacial adhesion between the BF and epoxy matrix, surface activation of the BF was carried out using low-pressure O2 and H2-Ar plasma under various conditions. The interfacial shear strength (IFSS), evaluated by a micro-droplet de-bonding test, was adopted to demonstrate the bonding effects at the BF/epoxy interphase. Compared to bare BF, the IFSS between the modified fibers and epoxy matrix was efficiently improved with an increment of 38.4% and 14.4% for O2 plasma and H2-Ar plasma treatment, respectively. Scanning Electron Microscope (SEM) and Atomic Force Microscopy (AFM) analysis indicated that H2-Ar plasma-treated BF had a much rougher and more rugged surface than O2 plasma-treated samples. X-ray Photoelectron Spectroscopy (XPS) and surface energy results revealed that O2 plasma activation could effectively increase the content of oxygenous groups on the BF surface, thus resulting in a higher total surface energy value. Based on the results, O2 plasma modification at a power of 200 W and pressure of 80 Pa for 0.5 min was considered to be the most favorable condition for the surface activation of BF. [ABSTRACT FROM AUTHOR]

Introduction. The active development of construction technologies entails the need to improve the properties of traditional materials, including giving them specific functional characteristics such as photocatalytic activity. One of the promising methods for solving this problem is the introduction of specialized additives into standard building mixes, which include photocatalytic composite materials. Within the framework of this article, the influence of various methods of fiber activation on the surface properties of a photocatalytic composite material created on its basis is considered. Materials and research methods. The effect of pre-activation of basalt (BF), glass (GF) and glass alkali-resistant (GAF) fibers on the surface properties of photocatalytic composite materials (PCM) based on them has been studied. The activation of the fiber surface consisted in thermal (T) and chemical (AA) treatment. The research methodology included: analysis of changes in the concentration of active centers of Brensted acids on the fiber surface before and after activation of their surface, after direct deposition of titanium dioxide on the obtained samples of various types of fibers, followed by an assessment of morphological changes. Results and discussions. The following growth trend has been established for the total number of active centers for PCM: PCM(BF+Т) → PCM(GF+AA) → PCM(BF+AA) → PCM(GAF+AA) →PCM(GF) → PCM(GAF+Т) → PCM(GAF) → PCM(GF+Т) → PCM(BF). According to the results of scanning electron microscopy, it was found that PCM(GF) and PCM(GAF+T) are characterized by a more uniform distribution of titanium dioxide particles over the entire surface of the fiber, creating a film-like appearance, unlike samples of PCM(BF) and PCM(GF), as well as PCM(GAF+AA), on which titanium dioxide particles are unevenly distributed, forming growths or aggregates. The analysis showed that sol-gel deposition of titanium dioxide has a significant effect on the properties of the fiber surface, which may affect the physical and mechanical characteristics of composites and their ability to self-clean, and should be taken into account when developing new functional materials with photocatalytic properties. Conclusion. The results obtained made it possible to evaluate the effectiveness of activation of the fiber surface for subsequent use as a substrate in the composition of photocatalytic composite materials

In this study, the impact of three different principles of surface activation techniques for polyamide fibers on the formation of conductive percolation during the subsequent electroless copper deposition process was investigated. The techniques used are (1) polyamide complexation using a solution mixture of calcium chloride, ethanol and water, (2) atmospheric plasma surface treatment and (3) grafting of 2‐hydroxyethylmethacrylate by radical induced polymerization. As a result, the percolation threshold was shifted to lower copper contents. The copper content required to form conductive structures was reduced ranged between 59% and 89%, depending on the activation techniques. Furthermore, the deposition time was reduced by 37%–57%, resulting in a faster build‐up of the percolation on the fabric. Changes in wetting behavior and substrate surface topography were identified to be the main reasons for these observations. While all applied surface activation techniques led to higher copper contents compared to unmodified reference, the atmospheric plasma modification led to the highest copper contents during the deposition process and a more uniform appearance of the metallised layer. Highlights: Three different fiber surface activation methods are evaluated.Fiber surface activation increases wetting and polymer‐metal adhesion.Activated polymer surface leads to faster copper deposition and percolation.Atmospheric plasma modification is the most efficient technique. [ABSTRACT FROM AUTHOR]

Silver nanocomposites (Ag-NPs/PVP) were synthesized through the reduction of Ag+ using Ethylene glycol (EG) and poly(N-vinylpyrrolidone) (PVP) as a protective agent in an alkaline medium. Characterization involved UV–Vis spectrum, and TEM image, confirming the well spread of the nanoparticles with a particle size of range 5–10 nm. Stability, assessed after three months, revealed a zeta potentialof −17 mV, identicating no agglomeration.. PVP role in decreasing the nanoparticle size was studied, attributed to the protective layer preventing aggregation.. The study enhanced the antibacterial activity of various cellulosic fabrics (cotton, linen, and viscose) by activating their surfaces through O2 plasma pretreatment at atmospheric pressure. Activation immobilized the fabric matrix by the extracting radicals fforming functional groups(C = O, –O–C = O, –COH, –COOH, and CH2–OH). Viscose demonstrated the highest effect. FTIR confirmed the formation of polar groups on the fabric surface. Activated cellulosic fabric was treated with Ag-NPs/PVP colloid solution and antibacterial activity was assessed against Staphylococcus aureus (S. aureus) andEscherichia coli (E. coli). Parameters such as: plasma exposure time, Ag-NPs/PVP concentration, and the pretreatment bath temperature were studied.SEM images and EDX spectra verified the presence of nitrogen and silver elements on the treated substrates surface. [ABSTRACT FROM AUTHOR]

This study introduces an innovative approach to enhance cotton fibers with integrated self-cleaning and antibacterial properties. By combining the potential of carbon quantum dots (CQDs) and silver nanoparticles (AgNPs), a distinct fabric modification strategy is developed. The synthesis mechanism of CQDs is outlined, alongside fabric activation using benzenesulfonyl chloride and triethylamine. The process of depositing CQDs and AgNPs onto the fabric surface is explained, emphasizing the importance of surface interactions and chemical affinity. Comprehensive characterization techniques, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were done to confirm the successful coating and nanoparticle integration. The confirmation of nanoparticles on the cotton fabric surface and subsequent results indicate an exceptional 128% increase in degradation activity compared to untreated fabric, coupled with significant enhancement in antibacterial efficacy against both Gram-positive and Gram-negative bacteria. In this report, the development of advanced multifunctional cotton fibers with improved stain resistance, self-cleaning capability, and enhanced antibacterial efficacy has been investigated. [ABSTRACT FROM AUTHOR]

Bio-based solutions for solid timber gluing have always been a very sensitive topic in wood technology. In this work, we optimize the gluing conditions of a starch–tannin formulation, which allows high performance in dry conditions and resistance to water dipping for 3 h, allowing for the D2 classification to be reached according to EN 204. It was observed that the starch–tannin formulations enhanced their performance by increasing the heating temperature, achieving satisfactory results at 140 °C for 13 min. The proportion of polyphenols in the mixture enhances the water resistance but is only tolerated until 20–30%. In particular, the addition of 10% tannin–hexamine enhances the water-resistant properties of starch for both quebracho and chestnut extract. The application of the jet of cold atmospheric plasma allows for good results with more viscous formulations, increasing their penetration in wood. Solid-state 13C-NMR analysis was also performed, and the spectroscopic information suggests establishing a coordination complex between starch and tannin. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) 1H molybdenum disulfide (1H-MoS2) is hard to be directly used in energy storage devices due to its inert basal plane and unfavorable 2D stacking. This work demonstrated how the basal plane of 1H MoS2 nanocrystals (NCs) can be activated to offer doubled specific capacitance by simple surface S depletions. Building on the expanded graphene with three-dimensional (3D) structures, as-prepared NCs were chemically grafted on the graphene surface to deliver stable energy storage and high capacitance, which overcame above challenges of 1H-MoS2. Aside from the mostly focused metastable phase, this work confirmed that the stable 1H Mo–S material is also promising in energy storage applications. [ABSTRACT FROM AUTHOR]

The adoption of lightweight materials in engineering applications has become more popular over recent years, with adhesives replacing traditional joining methods such as bolts and rivets. Adhesion science and related technologies are arising as cleaner options for sustainable production in modern industry, with adhesive-bonded joints increasingly being used as design solutions in complex products and assemblies. However, the use of structural adhesives has several significant drawbacks, most of which are related to environmental impact, linked to the nature of the adhesive substance, as well as product disassembly/disposal deriving from the fact that adhesive joints are usually irreversible. Within this context, the goal of this paper is to study adhesive joints in mechanical assemblies from a life cycle perspective, offering more comprehensive analysis tools and assembly solutions suitable for industries such as automotive, aerospace, and assembly/packaging machinery. A methodological framework for the comprehensive characterization of bonded joints using effective surface activation techniques has been created and tested. The first phase encompasses the production of samples for mechanical testing under static and fatigue loading conditions. The second includes the characterization of inputs/outputs (life cycle inventory—LCI) for life cycle assessment (LCA) of mechanical assemblies employing adhesive joints and innovative surface activation techniques. The final phase provides a set of eco-design actions based on a critical analysis of the obtained results. The outcomes demonstrate how it is possible to achieve optimal adhesive-bonded joint properties under specific working conditions (e.g., static or fatigue loading) while maintaining a low environmental load using novel surface pre-treatments such as laser and plasma technologies. These outcomes are supported by a case-study in which adhesive joints are applied to the mechanical assembly of a bottle gripper for a food packaging machine. The adoption of eco-design rules in adhesive joint applications will help designers in the development of suitable solutions for lightweight applications from a complete life cycle perspective. [ABSTRACT FROM AUTHOR]

High-entropy catalysts attract rising attention for promoting oxygen evolution reaction (OER) due to the advantages of multiple catalytic active sites, unique lattice distortion effect, interatomic d-band ligand effect, etc. However, it still needs to design new high-entropy catalysts with low cost and high efficiency to meet the requirement of large-scale applications. In this study, AlNiCuCoFeY amorphous alloy ribbon is prepared by melt spinning method. Then, the ribbon is etched in HF solution to form a nanoparticle modified ribbon, whose superficial species are further conversed to high-entropy oxides/Al alloy (HEO/Al alloy) or high-entropy fluorides/Al alloy (HEF/Al alloy) heterogeneous nanoparticles with a diameter of ∼20 nm by subsequent oxidization or fluorination process. Herein, the oxidized metallic elements with high valence state can promote the adsorption of OER. Due to the large surface area, multiple active sites, and the synergistic effect of different species, the HEO/Al alloy or HEF/Al alloy composite only need 293 and 261 mV overpotential to afford 10 mA cm−2 current density. This work discusses the design of high-entropy electrocatalysts and demonstrated a promising route to improve their OER electrocatalytic performance. [Display omitted] • AlNiCuCoFeYO x and AlNiCuCoFeYF x high-entropy catalyst with high efficiency are obtained. • The crucial role of introduction of O and F elements in high-entropy catalyst is discussed. • AlNiCuCoFeYO x and AlNiCuCoFeYF x nanocrystals are mixed with amorphous AlNiCuCoFeY nanocrystal. • HEO/Al alloy and HEF/Al alloy need 293 and 261 mV overpotentials @ 10 mA cm−2 current density. [ABSTRACT FROM AUTHOR]

Focusing on hydrophilic surface modification of poly(methyl methacrylate)/poly(methyl methacrylate‐co‐acrylic acid) (PMMA/PMMA‐co‐PAA) composite film, a copolymer is synthesized to improve the hydrophilicity and compatibility with PMMA matrix, and the composite film is subjected to surface activation using a sodium hydroxide solution. The infrared absorption peaks corresponding to –OH and –C═O functional groups become progressively weaker with the increase of copolymer content, indicating the formation of intermolecular hydrogen bonds. The hydroxyl absorption peak is significant and two new absorption peaks corresponding to the symmetric contraction and antisymmetric contraction of –COO– appear, indicating that sodium hydroxide solution can disrupt the intermolecular hydrogen bond and react with acrylic acid to form sodium acrylate to make the surface contain sodium elements. The elemental sodium content on the composite film can reach 1.9% and the nanostructures contain 20 times more sodium than the smooth parts, indicating the sodium acrylate can induce surface segregation of PMMA and form nanoparticle‐like structures to improve surface roughness. The hydrophilic component combined with the surface structure makes the contact angle less than 10°. Furthermore, thermostability can be slightly promoted by introducing the copolymer which is closely related to the intermolecular hydrogen bonding formed directly between the copolymer and the PMMA matrix. [ABSTRACT FROM AUTHOR]

Durability testing of low temperature solid oxide cells is challenging as degradation phenomena related to microstructural changes like nickel‐agglomeration are slow. In the present study, a nickel/gadolinia doped ceria (GDC) fuel electrode with a porous GDC‐interlayer towards the zirconia electrolyte was investigated. The electrode, designed for operating temperatures of 600°C, was tested at an elevated temperature of 900°C for up to 1100 h to accelerate aging. Contrary to every expectation, the electrodes showed continuous improvement in electrochemical performance. Impedance spectroscopy, the distribution of relaxation times analysis, scanning electron microscope and transmission electron microscope were applied to correlate electrochemical and microstructural changes. Structural analysis showed a significant Ni agglomeration accompanied by a decrease in triple phase boundary density. Furthermore, a minor particle growth in the GDC‐phase decreased the volume‐specific double phase boundary GDC/pore. Considering these microstructural changes, the decrease in active reaction sites should have increased the polarization resistance, but a decrease of about 32% was observed. The discrepancy between polarization resistance improvement and microstructural degradation might be attributed to an activation of the GDC‐surfaces in the electrode and the porous GDC‐interlayer. [ABSTRACT FROM AUTHOR]

In this work, we report a non‐enzymatic and metal‐free ethanol sensor based on 3D PLA‐graphene electrodes. We evaluated the optimal activation treatment for PLA‐graphene to achieve a sensor for monitoring ethanol levels in saliva samples, following the legal limits for drivers in various countries. The analytical performance of the sensor was determined through amperometric measurements, demonstrating a linear detection ranging supporting electrolyte (0.990–19.3 mmol L−1) and artificial saliva sample (0.990–17.4 mmol L−1), with respective limits of detection of 0.135 and 0.239 mmol L−1. The 3D‐printed sensor exhibited excellent repeatability and reproducibility. This method was effectively employed for ethanol detection, highlighting its potential as an alternative approach for assessing ethanol levels in drivers while considering diverse legal regulations across different countries. [ABSTRACT FROM AUTHOR]

A key challenge facing fabrication of nanomaterials is the ability to precisely control the surface morphology of the nanostructures through exploitation of process parameters. In this study, palladium thin films with carefully controlled surface morphologies are obtained through the careful choice of the reducing agent used during the pre‐plating activation step in the three‐step autocatalytic electroless plating consisting of 1) surface functionalization; 2) surface activation; and 3) deposition of the film onto alumina substrates. It is important to note that the reducing agents that influenced the surface morphology of the palladium thin films are employed in the pre‐plating activation step instead of the widely utilized electroless deposition step. It is revealed in the high‐resolution scanning electron microscope results that the hydrogen reducing agent yields a dense film with 3D spheroidal morphologies with an average cluster size of ≈415 nm while the hydrazine reducing agent produces a very smooth uniform surface morphology consisting of extremely small grains. The obtained results can be exploited in controlling and tailoring the surface‐dependent properties of the palladium thin film for applications in gas sensors, detectors, or palladium‐based membranes. [ABSTRACT FROM AUTHOR]

Zinc (Zn0) is a potent zero-valent metal (ZVM) capable of promoting both oxidation and reduction reactions in water. Similar to other ZVMs, Zn0's reactivity is rapidly retarded in water. This study aims to improve the activation of zinc particles (Zn0) by ultrasound in aqueous solutions buffered with 3-(N-morpholino)propanesulfonic acid (MOPS). Nitrite (NO2-) was chosen as a model compound to evaluate the effectiveness of ultrasonic zinc-MOPS treatment (US/Zn0/MOPS). Under similar experimental conditions, the maximum percent nitrite removal by Zn0 (8 g/L) in MOPS buffered solutions was around 45%, but it increased above 99% when ultrasound was introduced at 220.5 W. Results obtained from scanning electron microscopy-energy-dispersive X-ray spectroscopy and X-ray diffraction measurements have suggested that during US/Zn0/MOPS treatment, nitrite was reduced to nitrogen gas (N2) while Zn0 was oxidized to Zn2+ and/or Zn(OH)2. The results also indicated that the high nitrite reduction achieved by the combined method was due to a joint effect of both catalysts on zinc activation. [ABSTRACT FROM AUTHOR]

There are many technological ways to activate biocompatible surfaces, but in some cases, there are not reliable for elderly patients. It has been found that surfaces created using pulsating water jets have a structure similar to trabecular bone structures. Such a similar shape to the endoprosthesis stems would enable faster fixation. The paper presents a novel way of utilizing the water hammer effect caused by forced multiple droplet impingement with a spatial frequency of 40,000 i/s on Ti6Al4V titanium alloy surface under different technological conditions. The objective was to create a structured surface with desired values of surface profile parameters Ra and Rz to increase the possible potential for implant osseointegration, fixation and stability. Pulsating water jet was generated at pressures from 20 to 100 MPa using a circular nozzle with a diameter of 1.32 mm. Two different strategies of the jet trajectory, namely linear and cross-hatch strategy, were investigated. Results were compared with grit blasted followed by plasma spray-coated femoral stem for cementless total hip arthroplasty. It has been found that variation in the input parameters results in significant changes in the surface generated. Samples whose surfaces were generated using energy intensity lower than 5 KJ/mm2 and have surface roughness in the range Ra = 4 – 8 μm were selected for surface topography and morphology analysis along with the commercial femoral stem. SEM analysis revealed the absence of foreign contamination and steeper surface heights on pulsating water jet treated samples compared to standard femoral prosthetic. The cross-section images showed the presence of sub-surface voids and craters of different sizes due to the jet's action. Surface topology is similar to trabecular shape. This indicates that roughening the surface increases the surface area and thus has potential bone tissue ingrowth during osseointegration. [ABSTRACT FROM AUTHOR]

Processes of dressing the surface of glass fiber and their effect on the properties of composite materials based on polyetherimide filled with glass fibers were evaluated. It was found that preliminary thermal treatment of glass fibers and their subsequent treatment with a dressing agent, copolyhydroxyether based on di(4-hydroxyphenyl)sulfone, 4,4′-dioxydiphenylpropane, and 3-chloro-1,2-epoxypropane, allow obtaining polyether—etherimide composite glass-filled materials exhibiting improved physical and mechanical properties. [ABSTRACT FROM AUTHOR]

3D printing is a growing processing technology, which offers manufacturing of tailored, portable and integrated electrochemical energy harvesting device for realising next generation bioelectronics devices. Enzymatic biofuel cells (EBFCs) associated with biocatalysis uses bio friendly alternatives for energy harvesting. In addition, at microscale, the precision design and assembling of the bioelectrodes are complex procedures. The combination of software-assisted design and 3D printing has enabled the realization of customized electrochemical miniaturized devices for various applications. In this work, a completely 3D-printed EBFC at a micro level co-laminar flow-based configuration, names as 3D-µEBFC, integrated with new precise bioelectrode configuration has been demonstrated which will enhance the catalysis during the fuel flow in the device. The 3D-µEBFC consists of bioelectrode with comb-like structures with carbon black which helps in increasing the active surface to volume ratio available for electrocatalysis by 80% higher than plain electrodes. This micro-device produced an output power density of 13 µW/cm2 and open circuit voltage of 570 mV with an optimised flow rate of 18 ml/h. The 3D-printed bioelectrodes show high stability, which may transform the fabrication methodology by decreasing production costs and time, letting the development of complex‐shaped and purely 3D-printed micro-devices. [ABSTRACT FROM AUTHOR]

Polyoxymethylene (POM) and polypropylene (PP) materials are mass production thermo-plastics that are frequently used in the automotive industry. In many applications, these materials with low surface energy are prepared for bonding by mechanical abrasion or wiping with alcohol-based cleaners. The usability of the Cold Atmospheric Pressure Plasma (CAPP) method has been experimentally investigated in this study, instead of these preparation methods, which are bad for the environment. Increasing the surface energies of materials with plasma application has been a known method for a long time, but applications in vacuum environment have become possible under atmospheric pressure in recent years. In this way, the effectiveness of the method has remained the same, while its application and cost have improved. Experimental studies of the APP method to contribute to research in applications such as painting and bonding have been explained and it has been shown that the method can be an alternative for bonding applications of POM and PP materials, especially in the automotive sector. Considering that the APP method is an environmentalist process, it is understood that it will be an alternative in bonding of POM and PP materials. [ABSTRACT FROM AUTHOR]

This paper describes the design and operation of a low-cost plasma applicator based on a patented, swirled-type dielectric barrier discharge configuration with a treatment width up to 300 mm. Differences from earlier plasma applicators include: blown cylindrical dielectric barrier discharge, combining the functional properties of the plasma jet systems, arc and corona discharge blown in a single type of universal applicator, and the possibility of treating large areas of samples with cold plasma generated in a certain type of specific process gas mixture chosen according to the type of desired effect. We tested the effect of the plasma on a few materials such as cotton and linen fabrics, glass wafers and printing cardboard, proving that the generated plasma can easily make hydrophilic or hydrophobic surfaces. We also tried the plasma’s sterilizing effect on Escherichia coli (E. coli) bacteria. The results suggest that our plasma system can be successfully applied to medical and biological fields as well, where the removal of bacteria and their fragments is required.

Boron is a very promising and highly attractive fuel because of high calorific value. However, the practical applications in explosives and propellants of boron have been limited by long ignition delay time and low combustion efficiency. Herein, nano-Al and graphene fluoride (GF) as surface activated materials are employed to coat boron (B) particles to improve ignition and combustion performance. The reaction heat of nano-Al coated B/KNO3 and GF coated B/KNO3 are 1116.83 J/g and 862.69 J/g, respectively, which are higher than that of pure B/KNO3 (823.39 J/g). The ignition delay time of B/KNO3 could be reduced through nano-Al coating. The shortest ignition delay time is only 75 ms for B coated with nano-Al of 8 wt%, which is much shorter than that of pure B/KNO3 (109 ms). However, the ignition delay time of B/KNO3 coated with GF has been increased from 109 to 187 ms. B coated with GF and nano-Al shown significantly influence on the pressure output and flame structure of B/KNO3. Furthermore, the effects of B/O ratios on the pressure output and ignition delay time have been further fully studied. For B/KNO3 coated with nano-Al and GF, the highest pressures are 88 KPa and 59 KPa for B/O ratio of 4:6, and the minimum ignition delay time are 94 ms and 148 ms for B/O ratio of 7:3. Based on the above results, the reaction process of boron coated with GF and nano-Al has been proposed to understand combustion mechanism.

Low pressure drop is highly desirable for respiratory filters. Surface activation plays an important role to enhance the filtration performance of respiratory filters. In this study, a three-layer composite respiratory filter was developed using a combination of polypropylene (PP) nonwoven layers and chitosan nanofibres (CSNF) with variable coating time (h) during the electrospinning process. To study the impact of surface activation on filtration performance, the outer surface of all the samples were modified using low-pressure plasma treatment. Filtration performance testing was conducted to determine the filtration efficiency (%), pressure drop (Pa), and quality factor (Q) results, before and after the surface treatment. The maximum values of filtration efficiency and quality factor achieved were 99.99% and 0.068, respectively. The lowest value of the pressure drop was 16.12 Pa. All the low-pressure plasma-treated samples showed higher filtration efficiency and quality factor compared to untreated samples due to a more effective capturing mechanism. However, pressure drop results indicated no significant difference. Furthermore, the decay of plasma treatment impact was analysed by using drop shape analysis method to measure the water contact angle on the surface of the samples. Results showed a gradual decrease in surface modification impact and the surface of the treated samples changed from hydrophilic to hydrophobic with the passage of time. [ABSTRACT FROM AUTHOR]

High‐performance self‐lubricating polyphenylene sulfide (PPS)/carbon fiber (CF) composites were obtained by treating the CF surface with heat‐treated cyclic phenylene sulfide oligomers (CPS). The influence of CPS treat conditions on the structure and properties such as mechanical and tribological performance of the composites were studied in detail. The results indicate that the PPS/CPS‐sized CF composites exhibit higher mechanical strength and better tribological performance than the PPS/original CF composites, especially under the condition of higher loads and speeds (300 N × 200 rpm and 200 N × 200 rpm). The performance enhancement is reasonably ascribed to the improved compatibility of the modified CF with the PPS matrix. Further structural analysis reveals that the modified CF treated at 300°C under N2 (CF‐300N) has the most similar structure to the PPS matrix, which makes the comprehensive performances of PPS/CF‐300N composites superior to the products obtained under the other heat‐treatment conditions. [ABSTRACT FROM AUTHOR]

Surface engineering of chromium-oxide-passivated alloys (e.g., stainless steels) by low-temperature infusion of interstitial solutes (carbon, nitrogen) from a gas phase requires "surface activation" by removing or perforating the passivating oxide film. We demonstrate a new approach for surface activation based on pyrolysis of a reagent powder, introduce advanced methodology to study its microstructure, and compare it to an established activation method. Rather than a bare alloy surface, stripped of its oxide, we find that an "activated" surface involves a reaction layer containing high concentrations of Cl, carbon, or nitrogen. We propose a model for the microscopic mechanism of surface activation that will enable future systematic development toward more effective process schemes. [ABSTRACT FROM AUTHOR]

Wax-based additives have been widely used in asphalt pavement for their preferable environmental benefits. However, poor compatibility between wax-based warm mix additives and asphalt easily leads to precipitation of wax and cracking of asphalt pavement. Plasma treatment can effectively modify the surface of various materials. This study applies plasma treatment to improve the surface properties of wax-based additives for compatibility improvement in asphalt binder. Compatibility of two different wax-base additives in asphalt binder before and after surface treatment is investigated via cigar tube test and morphology test. In parallel, rheological properties of wax-modified asphalt are characterized from the perspectives of rotational viscosity, rutting resistance, and fatigue performance. Results show the enhanced surface roughness and chemical activity of wax-based additives after plasma treatment. The adhesion between waxes and the asphalt matrix is significantly improved. Waxes within binder are uniformly dispersed after plasma treatment. The incorporation of surface activated wax helps to promote the viscosity reduction of asphalt binder. Furthermore, the high-temperature performance of wax-based asphalt after surface activation treatment of wax is significantly improved, especially for fatty acid amide waxes. As for fatigue performance, plasma treatment improves the fatigue resistance from a compatibility perspective. Therefore, plasma has great promise for facilitating wax-modified asphalt properties from a compatibility perspective. [ABSTRACT FROM AUTHOR]

In order to study the effect of pre - oxidation treatment on the quality of the nitriding layer of stainless steel parts, quenched and tempered samples were treated with different pre - oxidation and sand blowing treatments before nitriding. The color of the preoxidized film was observed visually. The microstructure, depth, hardness, and brittleness of nitriding layer were measured by metallographic microscope and hardness tester. Results showed that the passivation film on the surface of 1Cr11Ni2W2MoV stainless steel could be destroyed if the steel was preoxidized at 550 ℃ for 5～20 min before nitriding. So the hardness, depth and structure of the nitriding layer could meet the technical requirements for nitriding if treated so. Furthermore, the uniformity and nitriding speed of the layer were better than that of the layer with only sand blowing treatment before nitriding.

Cold plasma activation has been considered as a green and effective technological approach for functionalization of solid surfaces. In the current study, we introduce a versatile technique known as microbubble-enhanced cold plasma activation (MB-CPA) for surface modification of polymer plates and nanoparticles in flowing liquid phase. Corona plasma is generated at the inlet of a venturi tube, thereby creating a highly excited state in the air. Reactive nitrogen and oxygen species (RNOS) are transferred from the gas phase to the suspension flow in the form of plasma microbubbles. Two types of polymer-based nanoparticles in the suspension, namely polymethyl methacrylate (PMMA) of 16–154 nm and polycaprolactone (PCL) of 30–225 nm, are synthesized using nano-precipitation method. Through the degradation of model compounds, the polar organic solvent, acetone and ethanol, is found to promote or suppress the production of active species. In addition, the efficiency of the MB-CPA treatment depends on the solvent composition, making this technology a controllable and efficient strategy for the surface modification of nanoparticles. The findings indicate that plasma activation effectively reduces the negative surface zeta-potentials and induces aggregation and separation in the suspensions. The infrared spectra of the treated nanoparticles reveal that plasma activation leads to the formation of N H and C N bonds situated on the surface of PMMA. Our work demonstrates that organic-solvent involved MB-CPA emerges as a promising method for the surface modification of nanoparticles in the flow condition. [Display omitted] • Surface functionalization of nanoparticles in fluidic suspension by cold plasma. • Microbubbles enhance active species transportation from air to liquid phase. • Controlled reactive species from plasma by tuning organic solvent in liquid phase. [ABSTRACT FROM AUTHOR]

The structure and performance of polyurethane (PU) foams are strongly driven by the stoichiometry of the polyaddition reaction, quantitatively described by the isocyanate index. It determines the balance between isocyanate and hydroxyl groups in the reacting system and is affected by the introduction of additional functionalities originated, e.g., from applied fillers. Nevertheless, this issue is hardly taken into account in research works. Herein, the structure and performance of PU/ground tire rubber (GTR) composites differing in their isocyanate index (from 0.8 to 1.2) and prepared with and without considering the GTR functionalities in formulation development were investigated. Incorporating GTR into the PU matrix led to a reduction in average cell diameter (from 2 to 30% depending on the isocyanate index) compared to unfilled foams. However, formulation adjustments did not show a significant impact on cellular structure. The only decrease in open cell content was noted, from 10% for the 0.9 index to 40% for 1.2. Such changes were related to the increasing strength of the PU cellular structure able to maintain inside the increasing amount of carbon dioxide. On the other hand, considering hydroxyl values of GTR noticeably affected the thermomechanical performance of composites. The shift of glass transition temperature (Tg), even by 10 °C for 1.2 isocyanate index, enhanced the performance of materials, which was expressed in an 8–62% drop in the composite performance factor, pointing to the enhanced reinforcing effect resulting from filler incorporation. The stiffening of foams, related to the variations in PU segmental structure, also caused minor changes in the course of thermal degradation of PU/GTR composites due to the inferior thermal stability of hard segments. The obtained results provide important insights into the development of formulations of PU composites filled with materials containing reactive functional groups able to disrupt the stoichiometric balance of the polyaddition reaction. [ABSTRACT FROM AUTHOR]

Polyester-based scaffolds are of research interest for the regeneration of a wide spectrum of tissues. However, there is a need to improve scaffold wettability and introduce bioactivity. Surface modification is a widely studied approach for improving scaffold performance and maintaining appropriate bulk properties. In this study, three methods to functionalize the surface of the poly(lactide-co-ε-caprolactone) PLCL fibres using gelatin immobilisation were compared. Hydrolysis, oxygen plasma treatment, and aminolysis were chosen as activation methods to introduce carboxyl (-COOH) and amino (-NH2) functional groups on the surface before gelatin immobilisation. To covalently attach the gelatin, carbodiimide coupling was chosen for hydrolysed and plasma-treated materials, and glutaraldehyde crosslinking was used in the case of the aminolysed samples. Materials after physical entrapment of gelatin and immobilisation using carbodiimide coupling without previous activation were prepared as controls. The difference in gelatin amount on the surface, impact on the fibres morphology, molecular weight, and mechanical properties were observed depending on the type of modification and applied parameters of activation. It was shown that hydrolysis influences the surface of the material the most, whereas plasma treatment and aminolysis have an effect on the whole volume of the material. Despite this difference, bulk mechanical properties were affected for all the approaches. All materials were completely hydrophilic after functionalization. Cytotoxicity was not recognized for any of the samples. Gelatin immobilisation resulted in improved L929 cell morphology with the best effect for samples activated with hydrolysis and plasma treatment. Our study indicates that the use of any surface activation method should be limited to the lowest concentration/reaction time that enables subsequent satisfactory functionalization and the decision should be based on a specific function that the final scaffold material has to perform. [ABSTRACT FROM AUTHOR]

Maddenin dördüncü hali olan plazmayı kullanan atmosferik basınçlı plazma işlemi otomotivde boyanabilirlik ve yapışma, tekstilde nem tutma, hava geçirgenliği, ağırlık azaltma ve kir iticilik, gıdalarda bakteri inaktivasyonu ve tıpta iyileştirme hızlandırma gibi birçok alanda kullanılmaktadır. Atmosferik basınçlı plazmanın (ABP) polimerler üzerinde kullanılması yüzey modifikasyonu, yüzey aktivasyonu sağlaması, yüzey temizliği gibi avantajlara sahip olması, pek çok kombinasyonu olması ve parametrelerinin (güç, gaz akış debisi vb.) kontrolü ile beklenen özellikleri sağlaması nedeniyle önemli ve popülerliği artan bir konudur. Bu derleme çalışmasında atmosferik basınçlı plazma hakkında genel bilgiler verildikten sonra özellikle polipropilen (PP) malzeme üzerinde atmosferik basınçlı plazma yönteminin uygulamaları örneklenmiş ve benzer alanlarda yapılan çalışmalarla karşılaştırmalar yapılmıştır.

In recent years, the demand for highly integrated and lightweight components has been rising sharply, especially in plastics processing. One strategy for weight-saving solutions is the development of conductive tracks and layouts directly on the polymer housing parts in order to be able to dispense with the system integration of additional printed circuit boards (PCB). This can be conducted very advantageously and flexibly with laser-based processes for functionalizing polymer surfaces. In this work, a three-step laser-based process for subsequent selective metallization is presented. Conventional injection molded components without special additives serve as the initial substrate. The Laser-Based Selective Activation (LSA) uses picosecond laser pulses to activate the plastic surface to subsequently deposit palladium. The focus is on determining the amount of deposited palladium in correlation to the laser and scan parameters. For the first time, the dependence of the metallization result on the accumulated laser fluence (Facc) is described. The treated polymer parts are characterized using optical and scanning electron microscopy as well as a contact-type profilometer. [ABSTRACT FROM AUTHOR]

The article presents research on the potential use of organometallic compounds with the addition of antimony (III) oxide Sb2O3 as a coating additive that will make coatings susceptible to electroless metallization after prior surface irradiation with 193 nm wavelength laser radiation and a different number of laser pulses. The surface modification and activation effects were assessed by optical-imagining as well as by scanning electron microscopy (SEM) with energy dispersive analysis (EDX). It was found that the presence of Sb2O3 in the coating made it possible to reduce the content of the copper complex, causing an intensive surface ablation, resulting in the formation of a conical structure with a higher content of metallic copper nuclei. [ABSTRACT FROM AUTHOR]

[Display omitted] • Theranostic PU eso-sponge to palliate the negative effects of Endo-VAC therapy. • Novel theranostic implant free of radiofrequency and magnetic resonance NPs. • Bacteria killing efficacy synchronously detected and promoted by Raman sources. • A challenge methodology, affordable and reproducible. Herein, a facile approach toward converting a three-dimensional polyurethane sponge (PUS), employed in endoluminal vacuum-assisted closure (endo-VAC) therapies, in a theranostic material able to detect and to inhibit bacteria growth, has been reported. The endo-VAC PUS presented sensitivity to Gram-positive and Gram-negative bacterial species thanks to its functionalization with gold and silver antibacterial nanoparticles (NPs). PUS with chitosan-stabilized Au-NPs achieved 5.26 ± 0.17 logs and 2.78 ± 0.34 logs of reduction of bacteria growth, whereas the sponges functionalized with phenolated lignin Ag-NPs offered slightly inferior values (4.77 ± 0.36 logs and 2.03 ± 0.37 logs, respectively), against Escherichia coli and Staphylococcus aureus pathogens, respectively, after the application of photothermal ablation. The in vitro antimicrobial studies were contrasted with the in-situ monitoring of bacteria localization and inactivation with excitation lasers of 532 and 785 nm wavelengths, respectively, in the Raman equipment. The novel theranostic nano-enabled antimicrobial PU sponges offer unprecedented possibilities for the improvement of the endo-VAC treatments and extrapolation of the methodology to other plastic-based implants to combat antimicrobial resistances. [ABSTRACT FROM AUTHOR]

In this study, structural, stability and electrical properties of Al 0.5 Ga 0.5 N nanowires are analyzed in detail under different Cs activation conditions including the activation of Cs, Cs/O, and Cs/NF 3 based on first principles and density functional theory (DFT). It is proved that Cs/NF 3 adsorption provides superior structural stability and lower work function compared to Cs adsorption alone, which significantly improves photoelectric response and quantum efficiency, especially at high Cs coverage. In addition, Cs adsorption is affected by adsorption saturation at high Cs coverage, but 3Cs/NF 3 model exhibits a more stable and persistent low-work function, which effectively mitigates the negative effects of Cs saturation. And the variation of average dipole moment of 3Cs/O and 3Cs/NF 3 activated nanowires coincides with decrease of work function. • Structural, stability and electrical properties of activated Al 0.5 Ga 0.5 N nanowires are analyzed in detail. • 3Cs, 3Cs/O and 3Cs/NF 3 activated models are crucial for understanding photovoltaic performance of Al 0.5 Ga 0.5 N NW. • For 3Cs/O and 3Cs/NF 3 activated nanowires, variation of average dipole moment coincides with decrease of work function. [ABSTRACT FROM AUTHOR]

• The stability and electronic properties of activated Al 0.5 Ga 0.5 N surface adsorbed by residual gas are discussed in detail. • Activated Al 0.5 Ga 0.5 N surface is not easily adsorbed by residual gases compared to pristine surface. • The s -electron state of residual gas forms deep levels in valence band, p -electron state forms shallow levels. • Work function of activated thin film surface increase after adsorbing residual gas. To study effect of residual gas in vacuum system on structure and electrical performance of activated AlGaN photocathodes, adsorption models for H 2 O, CO and CO 2 adsorbed on Al 0.5 Ga 0.5 N activated surfaces are established and investigated. The results indicate that activated Al 0.5 Ga 0.5 N surfaces are not easily adsorbed by residual gases compared to pristine surface. For Al 0.5 Ga 0.5 N thin film, H 2 O and CO exhibit higher affinity for adsorption on Cs/NF 3 -activated surfaces, while CO 2 shows greater tendency to adsorb on Cs-activated surface·H 2 O, CO and CO 2 are most easily adsorbed on Cs/NF 3 -activated surface for Al 0.5 Ga 0.5 N nanowires. Work function of Cs/NF 3 -activated thin film surface is 2.34 eV, and after adsorbing H 2 O, CO and CO 2 , work functions are 1.84 eV, 2.37 eV, and 3.43 eV, respectively. This means that residual gas will increase work function and is harmful to quantum efficiency improvement. [ABSTRACT FROM AUTHOR]

Liquid-phase technology for fabricating composite materials with a magnesium matrix and titanium reinforcement is proposed. Possibilities of improving adhesive bonding between composite components under casting conditions with preliminary deposition of an aluminum layer on titanium reinforcement and process activation with chloride-fluoride fluxes are considered. Cohesive strength between magnesium and titanium within composites is determined. Tensile tests of composite material specimens are performed and metallographic and x-ray spectrum analyses are conducted. The most effective activating flux compositions are proposed after analyzing composite material structure. Mechanical property tests for composites prove the efficiency of reinforcing a magnesium matrix with titanium. [ABSTRACT FROM AUTHOR]

Boron powder has been considered as a prime candidate as an additive in solid fuels or propellants. Unfortunately, boron ignition and combustion is hindered by the pre‐existing B2O3 surface layer which slows the oxidizer attack on the underlying boron particles. Therefore, removing the pre‐existing B2O3 surface layer is critical to improve the ignition and combustion performance of boron. Herein, an in‐situ coating strategy is reported to be very effective in removing the pre‐existing B2O3 surface layer of boron powder and improving its combustion performance. Through the in‐situ coating process in ethanol, flammable 3‐aminophenol/formaldehyde resin (AF) protection layer will be formed on the surface of the boron powder, replacing the pre‐existing B2O3 surface layer, and preventing the surface reoxidation of the boron powder. Comparing with the untreated boron powder, such coated boron powder exhibits higher burning rate and can be ignited at lower temperature. This in‐situ coating strategy can not only contribute to the extensive utilization of boron powder in high enthalpy fuels and propellants, but also shed light on the surface modification of functional materials in different fields. [ABSTRACT FROM AUTHOR]