Thermal spraying has been present for over a century, being greatly refined and optimized during this time. It has become nowadays a reliable and cost-efficient method to deposit thick coatings with ...a wide variety of feedstock materials and substrates. Thermal-sprayed coatings have been successfully applied in fields such as aerospace or electricity production, becoming an essential component of today’s industry. To overpass the traditional capabilities of those coatings, new functionalities and coherent responses are being integrated, opening the field of functional and smart coatings. The aim of this paper is to present a comprehensive review of the current state of functional and smart coatings produced using thermal spraying deposition. It will first describe the different thermal spraying technologies, with a focus on how different techniques achieve the thermal and kinetic energy required to form a coating. It will as well focus on the environment to which feedstock particles are exposed in terms of temperature and velocity. It will first deal with the state-of-the-art functional and smart coatings applied using thermal spraying techniques; a discussion will follow on the fundamentals on which the coatings are designed and the efficiency of its performance; finally, the successful applications both current and potential will be described. The inherent designing flexibility of thermal-sprayed functional and smart coatings has been exploited to explore exciting new possibilities on many different fields. Some applications include, but not limited to, prevention of bacteria contamination and infection on hygienic environments. Here, thermal spray has been used to efficiently deposit antimicrobial compounds on medical furniture and appliances and to develop biocidal and biocompatible coatings for prosthetic implants. The attachment of hard and soft foulers such as algae or molluscs, which represents a considerable issue for any marine or freshwater installation, can be prevented on components where the use of traditional anti-fouling strategies such as paints is not optimal for certain materials (i.e., polymers). Another interesting approach pursued is the development of superhydrophobic surfaces, with contact angles as high as 160° and slide angles below 5°, leading to high droplet mobility. This adds capabilities as self-cleaning or corrosion resistance in addition to the characteristic robustness of thermal-sprayed coatings. The electric and magnetic properties of the feedstock materials have also led to the application of thermal spraying techniques in the creation of patterned structures with desired electromagnetic properties for their use on microelectronics. The possibility to intercalate layers of thermal-sprayed materials doped with optical-reactive elements has led to the development of online and offline temperature sensors which can be readily integrated in current thermal barrier coatings. To finalize the examples of the many applications of thermal-sprayed functional and smart coatings, autonomous self-healing or self-lubricant coatings have been developed. Advantage has been taken of a beneficial phase transformation triggered by the corresponding event (such as a crack or the tribological interactions, respectively) to promote self-healing. Another approach has been the release of an encapsulated component which effectively heals the coating or provides lubrication when required. All these exciting developments pave the way for the numerous applications that are to come in the next decade, making the field of thermal-sprayed coatings a unique opportunity for research and development.
In recent years there is progressive research conducted on modification of textile and nanoparticles for long-lasting performances without compromising the sensorial and non-sensorial comfort. The ...appropriate finishing treatment of textile is of great concern to impart comfort along with durable multifunctional characters. The main objective of this study was to achieve the durable functionality without compromising the comfort and physical properties of cotton fabric. TiO
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nanoparticles have been modified with two different silane coupling agents such as (3-Glycidoxypropyl)trimethoxysilane (GPTS) and 1,2-Bis(triethoxysilyl)ethane (BTSE) using different concentrations. The modified nanoparticles were characterized using Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) to confirm the modification and fixing of chemicals at the surface. Modified nanoparticles were applied on textile by pad-dry-cure method. The treated cotton fabrics were washed to confirm the adhesion of nanoparticles after several washing cycles. The durable ultraviolet (UV) blocking capabilities were analyzed before and after washing. Then, comfort properties were evaluated and compared to made selection of best silane coupling agent having minimum effect on inherent properties of cotton textiles.
Nature has proven to be a treasure resource of bioactive metabolites. In this regard, Tamarix aphylla (F. Tamaricaceae) leaves crude extract was investigated for its gastroprotective effect against ...indomethacin-induced damage to the gastric mucosa. Additionally, phytochemical investigation of the methanolic extract afforded eight flavonoids' derivatives (1-8). On pharmacology networking study, the isolated compounds identified 123 unique targets where only 45 targets were related to peptic ulcer conditions, these 45 targets include 11 targets specifically correlate to gastric ulcer. The protein-protein interaction defined the PTGS2 gene as one of the highly interacted genes and the complete pharmacology network defined the PTGS2 gene as the most represented gene. The top KEGG signaling pathways according to fold enrichment analysis was the EGFR tyrosine kinase inhibitor resistance pathway. As a result, these findings highlighted the significance of using T. aphylla leaves crude extract as an anti-gastric ulcer candidate, which provides a safer option to chemical antisecretory medicines, which are infamous for their negative side effects. Our findings have illuminated the potent anti-inflammatory and antioxidant effects of T. aphylla, which are likely mediated by suppressing IL-1β, IL-6, TNF-α, and MAPK signaling pathways, without compromising gastric acidity.
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•Chromia/graphene nanoplatelets coatings are deposited with suspension thermal spray.•The structural integrity of graphene nanoplatelets is preserved upon spray.•Graphene ...nanoplatelets lower the coefficient of friction against alumina by 15%.•Specific wear rate is also lowered by 20% (coating) and 70% (counterbody).
Cr2O3 (chromia) coatings have been widely used in wear and corrosion resistant applications thanks to their good tribomechanical properties, and graphene nanoplatelets (GNPs) have been employed as nanofillers to further improve these properties. In this work, we propose a process to deposit chromia/GNPs composite coatings on stainless steel substrates using Suspension High Velocity Oxy-Fuel (S-HVOF) thermal spray. The coating showed good microhardness, with successful incorporation of GNPs showing no or minor spray-induced degradation. Compared to a chromia-only coating, the tribological performance improved: both coating and alumina counterbody specific wear rates lowered by 20 and 70% respectively and coefficient of friction decreased by 15%. This study shows a non-expensive and simple method to incorporate GNPs to improve material performance in large scale.
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•Computational design of nanosensor for common pollutants based on Green Phosphorene (GreenP) Monolayer.•Improved sensitivity and selectivity towards toxic NO2 by means of foreign ...atom substitution.•Appropriate binding energies and measurable changes in the band gaps.•In addition to DFT, employment of statistical thermodynamic, and the non-equilibrium Green’s function approach.
Green phosphorus and its monolayer variant, green phosphorene (GreenP), are the recent members of two-dimensional (2D) phosphorus polymorphs. The new polymorph possesses the high stability, tunable direct bandgap, exceptional electronic transport, and directionally anisotropic properties. All these unique features could reinforce it the new contender in a variety of electronic, optical, and sensing devices. Herein, we present gas-sensing characteristics of pristine and defected GreenP towards major environmental gases (i. e., NH3, NO, NO2, CO, CO2, and H2O) using combination of the density functional theory, statistical thermodynamic modeling, and the non-equilibrium Green’s function approach (NEGF). The calculated adsorption energies, density of states (DOS), charge transfer, and Crystal Orbital Hamiltonian Population (COHP) reveal that NO, NO2, CO, CO2 are adsorbed on GreenP, stronger than both NH3 and H2O, which are weakly physisorbed via van der Waals interactions. Furthermore, substitutional doping by sulfur can selectively intensify the adsorption towards crucial NO2 gas because of the enhanced charge transfer between p orbitals of the dopant and the analyte. The statistical estimation of macroscopic measurable adsorption densities manifests that the significant amount of NO2 molecules can be practically adsorbed at ambient temperature even at the ultra-low concentration of part per billion (ppb). In addition, the current-voltage (I–V) characteristics of S-doped GreenP exhibit a variation upon NO2 exposure, indicating the superior sensitivity in sensing devices. Our work sheds light on the promising application of the novel GreenP as promising chemical gas sensors.
This article examines the level of local community engagement in development initiatives in the northeast of Nigeria, highlighting the importance of local community engagement in the successful ...implementation and sustainability of development projects and their current challenges. The study delves into the existing literature and reports using a desk research methodology, providing a comprehensive overview of current practices and the barriers hindering effective community involvement. This exploration identifies several key research gaps, including the lack of consensus on effective community engagement measurement, insufficient understanding of participation dynamics, and limited investigation into the long-term effectiveness of capacity-building initiatives. In response to these gaps, the article proposes strategies to improve community engagement in the region, such as developing robust metrics for community engagement, implementing inclusive participation practices, and incorporating capacity-building components in development initiatives. The article underscores the critical need for further research in this area and advocates for more inclusive, sustainable, and effective community engagement in Northeast Nigeria’s development efforts.
Janus monolayers and their van der Waals heterostuctures are investigated by hybrid density functional theory calculations. MoSSe, WSSe, MoSeTe and WSeTe are found to be direct band gap ...semiconductors. External electric fields are used to transform indirect MoSTe and WSTe to direct band gap semiconductors. MoSSe-WSSe, MoSeTe-WSeTe and MoSTe-WSTe vdW heterostructures are also indirect band gap semiconductors with type-II band alignment. Similar to the corresponding monolayers, in some of the above mentioned vdW heterostructures an external electric field and tensile strain can transform indirect to direct band gaps, while sustaining type-II band alignment. Janus monolayers have lower values of the work function (
) than their vdW heterostructure counterparts. Furthermore, absorption spectra, absorption efficiency, and valence(conduction) band edge potentials are calculated to understand the optical and photocatalytic behavior of these systems. Red and blue shifts are observed in the position of excitonic peaks due to the induced strain in Janus monolayers. Strong device absorption efficiencies (80-90%) are observed for the WSeTe, MoSTe and WSTe monolayers in the visible, infra-red and ultraviolet regions. Energetically favourable band edge positions in Janus monolayers make them suitable for water splitting at zero pH. We find that the MoSSe-WSSe heterostructure and the MoSTe monolayer are promising candidates for water splitting with conduction and valence band edges positioned just outside of the redox interval.
Janus monolayers and their van der Waals heterostuctures are investigated by hybrid density functional theory calculations.
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Despite the substantial body of research investigating the use of liposomes, niosomes and other bilayer vesicles for drug delivery, the translation of these systems into licensed ...products remains limited. Indeed, recent shortages in the supply of liposomal products demonstrate the need for new scalable production methods for liposomes. Therefore, the aim of our research has been to consider the application of microfluidics in the manufacture of liposomes containing either or both a water soluble and a lipid soluble drug to promote co-delivery of drugs. For the first time, we demonstrate the entrapment of a hydrophilic and a lipophilic drug (metformin and glipizide respectively) both individually, and in combination, using a scalable microfluidics manufacturing system. In terms of the operating parameters, the choice of solvents, lipid concentration and aqueous:solvent ratio all impact on liposome size with vesicle diameter ranging from ∼90 to 300nm. In terms of drug loading, microfluidics production promoted high loading within ∼100nm vesicles for both the water soluble drug (20–25% of initial amount added) and the bilayer embedded drug (40–42% of initial amount added) with co-loading of the drugs making no impact on entrapment efficacy. However, co-loading of glipizide and metformin within the same liposome formulation did impact on the drug release profiles; in both instances the presence of both drugs in the one formulation promoted faster (up to 2 fold) release compared to liposomes containing a single drug alone. Overall, these results demonstrate the application of microfluidics to prepare liposomal systems incorporating either or both an aqueous soluble drug and a bilayer loaded drug.
Efficient chemical gas detection is of great importance for various functionalities (such as leakage detection of hazardous and explosive gases in industrial safety systems). The recent discovery of ...2D black phosphorene (BlackP) has created intensive interests toward nanosensors because of its maximized surface-to-volume ratio and exceptional carrier mobility that potentially deliver the superior performance than the conventional transition-metal oxides sensors. In this work, we have performed first-principles DFT calculations coupled with the statistical analysis to unravel the structural, electronic, and gas-sensing characteristics of pristine, defected, and metal-substituted BlackP toward toxic H2S and SO2 gas molecules. Our findings have revealed that pristine BlackP weakly interacts with both H2S and SO2 by van der Waals (vdW) forces characterized by the small binding energies. The analysis of electronic properties via the density of states (DOS) indicates that there is a negligible change in DOS after gas exposure, which confirms insensitive sensing. To intensify the binding energies, we have considered defects (mono-, di-, tri-, and quad-vacancy) and substitutional impurities (Ti, Si, Mn, and Fe) as the incentives. The presence of mono- and divacancies remains less energetically sensitive to both gas species because of the low adsorption energies. Meanwhile, tri- and quad-vacancies induce the dissociative adsorption, not suitable for the reversible adsorption–desorption cycles. Substitutional doping by Fe atoms is found to be a feasible approach to enhance the sensing resolution of SO2 detection because of the remarkable adsorption energy incorporated with the substantial variation in DOS after gas exposure. This modification in electronic properties is facilitated by the charge transfer mechanism from Fe 3d to P 3p which can generate the measurable electrical signal detected by the external circuit of the sensor.
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