Addition Of Nanomaterials Research Articles

Building rapid water transport channels within thin-film nanocomposite membranes based on 2D mesoporous nanosheets

The fabrication of novel thin-film nanocomposite (TFN) membranes with superior flux, rejection as well as prolonged stability is being requested by membrane industries for saving energy and cost. In this regard, in the present research work we developed novel TFN membranes using amine-rich synthetic talc (NHST) nanosheets within diethylenetriamine (DETA) and trimesoyl chloride (TMC) monomers over a polydopamine (PDA) coating layer. Different concentrations (0.2–1 %) of NHST nanosheets are applied for the fabrication of TFN membranes and comparatively examined with a thin-film composite (TFC) membrane. In-situ synthesized NHST nanosheet phases are confirmed by several characterization techniques and results are explored in depth. All prepared membranes are well investigated to confirm the incorporation of NHST by several characterization techniques, like FE-SEM, ATR-FTIR, HR-TEM, XPS, PXRD, TGA, and contact angle. It is found that a small amount of NHST doping in the TFN layer considerably improved the performance in the form of permeability and rejection. The developed TFN membranes showed hydrophilic characteristics as confirmed by the contact angle. Water flux performance of TFN membranes was also observed comparatively higher than TFC membranes. Optimized NHST-PDT-TFN2 membrane with NHST concentration 0.5 % resulted in 98.96, 95.35, 93.83 and 21.66 % rejection for Na2SO4, MgSO4, CuSO4 and NaCl salts, respectively together with permeance up to 24.45, 22.72, 26.45 and 30.75 Lm−2h−1b−1. The present research finding concludes that the incorporation of a little quantity of NHST nanosheets in the TFN layer plays a unique potential role in the enhancement of flux and rejection of targeted mineral salts. Additionally, the NHST-PDT-TFN membranes revealed outstanding antibacterial properties signifying that contact with microorganisms does not affect the performance and sustains the fouling resistance. The antifouling study of the membranes concluded that the addition of nanomaterials has led to enhanced antifouling tendency and low irreversible fouling, improving the longevity of the membranes.

Analytical solution for chloride diffusion in concrete with the consideration of nonlinear chloride binding

An analytical study is presented on the diffusion of chloride in concrete coupled with the effect of nonlinear chloride binding. A double-segment piecewise linear chloride binding isotherm (the DS-PWL isotherm) is proposed that can fit well quite a number of experimentally measured chloride binding isotherms which were reported by many published works. The proposal of the DS-PWL isotherm makes feasible the development of analytical solutions for chloride diffusion in concrete that accommodate nonlinear chloride binding, which is not feasible at present. Based on the proposed isotherm, an analytical solution is obtained for one-dimensional diffusion of chloride in a semi-infinite concrete medium in the context of nonlinear chloride binding. The obtained solution is successfully validated against numerical solution for mathematical correctness while the proposed analytical model is shown to be in tolerably good agreements with a reported chloride diffusion experiment. Moreover, the proposed model is also shown to be in good agreements with the Freundlich-based model, exhibiting a desirable applicability. Parametric study is conducted using the proposed solution to examine the influence of each of the three DS-PWL characterizing parameters on chloride diffusion. Finally, the proposed solution is applied to investigating the influence of nanomaterial addition (the dosage of addition and the type of the nanomaterial added) on the service life of an RC structure member subjected to chloride ingress.

Incorporation of Nanomaterials in Glass Ionomer Cements-Recent Developments and Future Perspectives: A Narrative Review.

Glass ionomer cements (GICs), restorative materials with commercial availability spanning over five decades, are widely applied due to their advantages (including bio-compatibility, fluoride release, or excellent bonding properties). However, GICs have shortcomings. Among the disadvantages limiting the application of GICs, the poor mechanical properties are the most significant. In order to enhance the mechanical or antimicrobial properties of these materials, the addition of nanomaterials represents a viable approach. The present paper aims to review the literature on the application of different types of nanomaterials for the enhancement of GICs' mechanical and antimicrobial properties, which could lead to several clinical benefits, including better physical properties and the prevention of tooth decay. After applying the described methodology, representative articles published in the time period 2011-present were selected and included in the final review, covering the modification of GICs with metallic nanoparticles (Cu, Ag), metallic and metalloid oxide nanoparticles (TiO2, ZnO, MgO, Al2O3, ZrO2, SiO2), apatitic nanomaterials, and other nanomaterials or multi-component nanocomposites.

Revealing the mechanisms of polypyrrole (Ppy) enhancing methane production from anaerobic digestion of waste activated sludge (WAS)

Anaerobic digestion (AD) is a promising method for treating waste activated sludge (WAS), but the low methane yield limits its large-scale application. The addition of conductive nanomaterials has been demonstrated to enhance the activity of AD via promoting the direct interspecies electron transfer (DIET). In this study, novel conductive polypyrrole (Ppy) was prepared to effectively improve the AD performance of WAS. The results showed that the accumulative methane production was enhanced by 27.83% by Ppy, with both acidogenesis and methanogenesis being efficiently accelerated. The microbial community analysis indicated that the abundance of bacteria associated with acidogenesis process was significantly elevated by Ppy. Further investigation by metatranscriptomics revealed that fadE and fadN genes (to express the key enzymes in fatty acid metabolism) were highly expressed in the Ppy-driven AD, suggesting that Ppy promoted electron generation during acid production. For methanogenesis metabolism, genes related to acetate utilization and CO2 utilization methanogenesis were also up-regulated by Ppy, illustrating that Ppy facilitates the utilization of acetate and electrons by methanogenic archaea, thus potentially promoting the methanogenesis through DIET.

Synthesis and Characterization of Carbon Fiber Nanocomposite Using Titanium Dioxide and Silicon Carbide Nanomaterials

Carbon fiber reinforced polymers (CFRPs) have spread to a wide range of industries in recent decades, including the automobile, aeronautics, and space industries. Recently, the emergence of new requirements for improved properties and features has become one of the major drivers of the introduction of innovative methodologies and process optimization. In this study, the effect of nanomaterials on the behavior of carbon fiber-reinforced polymer (CFRP) composites was investigated experimentally. The grafting of TiO2 and SiC nanomaterials onto the surface of fibers was performed by mixing nanomaterials in the epoxy resin. CFRPs were manufactured using vacuum assisted resin transfer molding (VARTM) in this study and characterized using mechanical and thermal testing. The primary test parameters were carbon fiber with epoxy resin and 0% nanomaterials by weight. An increase in properties was observed in nanocomposite with 2% wt. of nanomaterials when compared with 0, 0.5, and 1% wt. Between 0 wt.% and 2 wt.%, the tensile strength, flexural strength, impact strength, hardness, and HDT properties were increased by 17%, 39%, 32%, 14% and 21%, respectively, due to the addition of nanomaterials into the resin.

Analysis of Load-Bearing Electrical Properties of Composite Materials Based on Homogenization Theory

In this study, the broadband dielectric spectrum of polyimide composites was examined using the homogenization theory. The findings demonstrate that the addition of boron nitride nanosheets (BNNSs) and silver nanoparticles (AgNPs) causes an increase in conductivity, dielectric constant, and dielectric loss of the composites but does not result in a surge in the three parameters; the results also demonstrate that an increase in temperature causes an increase in dielectric constant and dielectric loss of the composites. In addition, temperature has a bigger impact on the dielectric loss than it does on the dielectric constant. An increase in the amount of polarized charges and a shallower bulk trap depth can result from the addition of nanomaterials, according to research on thermally stimulated current in composite materials. The presence of the interfacial region, which made it simple to cause charge accumulation and simple to form conduction current, is primarily responsible for the significant increase in bulk conductivity of the composites at 50 Hz that occurred with the addition of more nanomaterials. The large rise in bulk conductivity of the composites at 50 Hz that happened with the addition of more nanomaterials is mostly due to the existence of the interfacial region, which made it simple to produce charge buildup and simple to form conduction current. The variation in volume conductivity when the doping ratio is less than 10 vol% is not significant due to AgNPs’ low concentration and ambiguous contribution to the conduction current. As the polarization temperature rises, the amount of polarization charges increases, but it has minimal effect on the bulk trap depth of the composites.

Research progress on durability of marine concrete under the combined action of Cl− erosion, carbonation, and dry–wet cycles

Abstract Marine concrete is a kind of construction material which is seeking its growing application in marine engineering. However, the marine concrete structures are exposed to aggressive environment and harmful ions. Therefore, it is crucial to improve the durability of marine concrete. The concrete structure located in the tidal zone is subjected to the dry–wet cycles caused by tidal action, chloride ion (Cl−) erosion in seawater, and CO2 erosion in air. When these factors work together, they cause great damage to the marine concrete structure. In view of the three environmental factors, namely, Cl− erosion, carbonation, and dry–wet cycles, taking fly ash, fibers, and nanomaterials as examples, this article expounds the research status of durability of marine concrete, introduces the latest research progress, the addition of fibers, fly ash, and nanomaterials can improve the Cl− corrosion resistance and dry–wet cycles resistance of marine concrete, while the addition of fly ash is unfavorable for carbonation resistance. And the future development trend of marine concrete is prospected.

Insights into the Enhancement Mechanisms of Molten Salt Nanofluids

The addition of nanomaterials to molten salts can significantly improve their thermal performance. To explore the enhancement mechanisms, this work prepared carbonate salt nanofluids with binary carbonate as base salt and 20 nm SiO2 and 20 nm MgO nanoparticles as additives by the commonly used aqueous solution method. Then, the key performance and micromorphology of the carbonate salt nanofluids are characterized by differential scanning calorimetry, thermal gravimetric analysis, laser flash analysis, and micromorphology analysis. Results showed that the 20 nm SiO2 nanomaterials instead of the 20 nm MgO nanomaterials exerted higher effects on latent heat while the 20 nm MgO nanomaterials instead of the 20 nm SiO2 nanomaterials exerted higher effects on the sensible heat, thermal conductivity, and high-temperature stability of carbonated salt. In addition, different nanostructures were observed in SiO2-based and MgO-based molten salt nanofluids, respectively. Innovatively, formation mechanisms of molten salt nanofluids were proposed based on cloud nuclei to explain the different enhancements in this work.

Investigation the properties of sustainable ultra-high-performance basalt fibre self-compacting concrete incorporating nano agricultural waste under normal and elevated temperatures

Producing sustainable concrete using waste materials has a noticeable impact on the environment. From another aspect, understanding the effect of high temperature on concrete can help in reduce the environmental fire impact and lower rehabilitation costs. This study presents a systematic experimental investigation to produce sustainable ultra-high-performance basalt fibre self-compacting concrete (UHPBF-SCC) using agricultural waste materials including nano sugar cane bagasse, nano cotton stalk ash and nano rice straw ash as cement replacement. The three dosages of nanoparticles are mechanically produced after heat treatment at 700°C. The performance of the three dosages of nanoparticles (partially replacing 1–5% of cement) was investigated in the presence of basalt fibre. This study also examines the effect of elevated temperatures of 300°C and 600°C on the behaviour of UHPBF-SCC. The physical properties, including passing ability, flowability and segregation resistance, were studied. Compressive strength, strength loss at elevated temperature, mass loss, ultrasonic pulse velocity, splitting, and flexure strength were also investigated. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDX) analysis were conducted to show the microstructure of the mixes. Mechanical characteristics are significantly increased in the presence of nanoparticles, more than 18% in compressive, 32% in tensile strength and 28% in flexure strength compared with the reference mix. SEM analysis showed compacted sections with high bonded matrix and high ITZ at normal conditions, but microcrack propagation appeared at 300°C and 600°C due to ettringite decomposition and evaporation of capillary and adsorbed water. EDX analysis showed high Ca/Si with the addition of nanomaterials.

The influence of nano-CaO and nano-Al2O3 and curing conditions on perlite based geopolymer concrete produced by the one-part mixing method

• Perlite-based geopolymer can be produced by one-part mixture method. • Nano-CaO affects the strength of perlite-based geopolymer concrete negatively. • Nano-Al 2 O 3 affects the strength of perlite-based geopolymer concrete positively. • Nano-additives were more effective in reducing the volume of macropores formed in geopolymer concrete. In terms of sustainability, alternative binders have been sought despite the environmental effects of CO 2 gas released as a result of cement production. In accordance with this purpose, geopolymer binders produced by activating aluminosilicate materials with alkalis are one of these alternatives. This study aimed to produce one-part geopolymer concrete from aluminosilicate-based perlite, which is rich in SiO 2, and to improve its mechanical properties by adding nanomaterials. The effect of using nano-Al 2 O 3 and nano-CaO at 1 %, 2 %, and 3 % by weight instead of perlite on the properties of geopolymer concrete under different curing conditions (heat + ambient and heat + water curing) was investigated with SEM (scanning electron microscope), XRD (X-ray Diffraction), t -Plot/BJH (specific surface area and pore size distribution) and FT-IR (Fourier Transform Infrared Spectroscopy) tests, the compressive strength, flexural strength, length change. As a result, the applicability of the one-part mixture method in the production of perlite-based geopolymer concrete has been determined. Nano-Al 2 O 3 was found to be effective in perlite-based geopolymer concrete in terms of compressive strength and the optimum curing condition was heat + ambient curing. The addition of nanomaterials especially prevented crack and pore formation and according to t -Plot/BJH analysis, were more effective in lowering the number of macropores generated in geopolymer concrete, but increased the number of micropores. Moreover, the nanoparticles had no discernible effect on the geopolymerization process of perlite-based geopolymer concrete.

Reaction kinetics, mechanical properties, and microstructure of nano-modified recycled concrete fine powder/slag based geopolymers

Nano-materials are increasingly being used as modified binder for improve the performance of cementitious materials. In this paper, nano-SiO2 and nano-Al2O3 were incorporated into the geopolymers formed by the mixture of construction solid waste (recycled concrete fine powder) and industrial solid waste (slag). The effects of the type and content of nanomaterials on the early reaction kinetics, physical and mechanical properties and microstructure of geopolymer composites were explored. Results show that the addition of nanomaterials mainly affected the dissolution stage of geopolymerization, played a nucleation effect and improved the reaction rate. The promotion effect of nano-Al2O3 was slightly greater than that of nano-SiO2. Based on the results of JMAK model, the formation of geopolymers composites was an one-dimensional heterogeneous nucleation control reaction, which followed a plate-like structure thickening mechanism. The addition of nanomaterials shortened the setting time. The incorporation of nano-Al2O3 was beneficial to improve the fluidity of geopolymer. Furthermore, the addition of the two nanomaterials could improve the compressive strength of geopolymers. The compressive strength tended to first increase and then decrease with increasing nano-SiO2 or nano-Al2O3 content. The optimal mixing ratio of nano-silica and nano-alumina were 1.2% and 1.6% respectively, and the 28-day compressive strengths were both 59.05 MPa, which were 23.35% higher than that without nano-materials. XRD and SEM-EDS analysis indicate that the incorporation of nanomaterials had no impact on the type of final products, but increased their number, particularly calcium-based gel products. The internal structure of geopolymer with nanomaterials was more dense and uniform than that without nanomaterials. The MIP observed that the addition of the two nano-materials reduced the porosity in the matrix, the number of macropores and the pore fractal dimension. The pore fractal dimension of geopolymer was negatively correlated with the compressive strength.

Nanomaterials and Technology Applications for Hydraulic Fracturing of Unconventional Oil and Gas Reservoirs: A State-of-the-Art Review of Recent Advances and Perspectives.

The application of hydraulic fracturing stimulation technology to improve the productivity of unconventional oil and gas reservoirs is a well-established practice. With the increasing exploration and development of unconventional oil and gas resources, the associated geological conditions and physical properties are gradually becoming more and more complex. Therefore, it is necessary to develop technologies that can improve the development benefits to meet these challenges. In recent years, improving the effect of hydraulic fracturing stimulation in unconventional oil and gas reservoirs through the use of nanomaterials and technologies has attracted increasing attention. In this paper, we review the current status and research progress of the application of nanomaterials and technologies in various aspects of hydraulic fracturing in unconventional oil and gas reservoirs, expound the mechanism and advantages of these nanomaterials and technologies in detail, and provide future research directions. The reviewed literature indicates that nanomaterials and technologies show exciting potential applications in the hydraulic fracturing of unconventional reservoirs; for example, the sand-carrying and rheological properties of fracturing fluids can be significantly enhanced through the addition of nanomaterials. The use of nanomaterials to modify proppants can improve their compressive strength, thus meeting the needs of different reservoir conditions. The fracturing flowback fluid treatment efficiency and purification effect can be improved through the use of nanophotocatalysis and nanomembrane technologies, while degradable fracturing completion tools developed based on nanomaterials can effectively improve the efficiency of fracturing operations. Nanorobots and magnetic nanoparticles can be used to more efficiently monitor hydraulic fracturing and to accurately map the hydraulic fracture morphology. However, due to the complex preparation process and high cost of nanomaterials, more work is needed to fully investigate the application mechanisms of nanomaterials and technologies, as well as to evaluate the economic feasibility of these exciting technologies. The main research objective of this review is to comprehensively summarize the application and research progress of nanomaterials and technologies in various aspects of hydraulic fracturing in unconventional oil and gas reservoirs, analyze the existing problems and challenges, and propose some targeted forward-looking recommendations, which may be helpful for future research and applications.

A stable porous vessel for photocatalytic degradation of Azocarmine G dye

Porous nanocomposite of polystyrene (PS) is fabricated by non-solvent induced phase separation, and with the addition of ZnO nanomaterials through electrospinning, the different evaporation rates of solvent/non solvent mixture causes phase separation and improves the porosity of the fiber. The spherical particles of ZnO are uniformly distributed within the polymer chains, creating a networking effect that further restricts the motion of the PS chains and higher pores generation. The specific surface area and average pore size values were respectively 48 m2/g and 82.5 nm for the PS/ZnO with 3 wt% filler concentration, much higher than the neat polymer (23 m2/g and 61.1 nm). The PS/ZnO composite showed 95% degradation efficiency when irradiated with natural sunlight for Azocarmine G dye. This study addresses the correlation of porous structural characteristic with the sunlight driven photocatalysis as the porous sites provide active centers for the catalysis to take place. The porous structural integrity is maintained, and improved with ZnO addition and promising catalysis efficiency is achieved. Moreover, the ZnO imparts excellent antibacterial activity against S. aureus bacteria and the PS/ZnO fibers show good functional and structural stability.

Seed Priming with Carbon Nanomaterials Improves the Bioactive Compounds of Tomato Plants under Saline Stress.

The consumption of food with a high content of bioactive compounds is correlated with the prevention of chronic degenerative diseases. Tomato is a food with exceptional nutraceutical value; however, saline stress severely affects the yield, the quality of fruits, and the agricultural productivity of this crop. Recent studies have shown that seed priming can mitigate or alleviate the negative effects caused by this type of stress. However, the use of carbon nanomaterials (CNMs) in this technique has not been tested for this purpose. In the present study, the effects of tomato seed priming with carbon nanotubes (CNTs) and graphene (GP) (50, 250, and 500 mg L−1) and two controls (not sonicated and sonicated) were evaluated based on the content of photosynthetic pigments in the leaves; the physicochemical parameters of the fruits; and the presence of enzymatic and non-enzymatic antioxidant compounds, carotenoids, and stress biomarkers such as hydrogen peroxide (H2O2) and malondialdehyde (MDA) in the leaves and fruits of tomato plants without saline stress and with saline stress (50 mM NaCl). The results show that saline stress in combination with CNTs and GP increased the content of chlorophylls (9.1–21.7%), ascorbic acid (19.5%), glutathione (≈13%), proteins (9.9–11.9%), and phenols (14.2%) on the leaves. The addition of CNTs and GP increased the activity of enzymes (CAT, APX, GPX, and PAL). Likewise, there was also a slight increase in the content of H2O2 (by 20.5%) and MDA (3.7%) in the leaves. Salinity affected the quality of tomato fruits. The physico-chemical parameters and bioactive compounds in both the stressed and non-stressed tomato plants were modified with the addition of CNTs and GP. Higher contents of total soluble solids (25.9%), phenols (up to 144.85%), flavonoids (up to 37.63%), ascorbic acid (≈28%), and lycopene (12.4–36.2%) were observed. The addition of carbon nanomaterials by seed priming in tomato plants subjected to saline stress modifies the content of bioactive compounds in tomato fruits and improves the antioxidant defense system, suggesting possible protection of the plant from the negative impacts of stress by salinity. However, analysis of the mechanism of action of CNMs through seed priming, in greater depth is suggested, perhaps with the use of omics sciences.

Recent advancements in enzyme-incorporated nanomaterials: Synthesis, mechanistic formation, and applications.

Over the past decade, nanotechnology has been developed and employed across various entities. Among the numerous nanostructured material types, enzyme‐incorporated nanomaterials have shown great potential in various fields, as an alternative to biologically derived as well as synthetically developed hybrid structures. The mechanism of incorporating enzyme onto a nanostructure depends on several factors including the method of immobilization, type of nanomaterial, as well as operational and environmental conditions. The prospects of enzyme‐incorporated nanomaterials have shown promising results across various applications, such as biocatalysts, biosensors, drug therapy, and wastewater treatment. This is due to their excellent ability to exhibit chemical and physical properties such as high surface‐to‐volume ratio, recovery and/or reusability rates, sensitivity, response scale, and stable catalytic activity across wide operating conditions. In this review, the evolution of enzyme‐incorporated nanomaterials along with their impact on our society due to its state‐of‐the‐art properties, and its significance across different industrial applications are discussed. In addition, the weakness and future prospects of enzyme‐incorporated nanomaterials were also discussed to guide scientists for futuristic research and development in this field.

Strength and microstructural properties of binary and ternary blends in fly ash-based geopolymer concrete

Carbon dioxide emissions and the consumption of natural resources related to the cement manufacturing have prompted the need to develop more sustainable and environmentally friendly types of concrete. Geopolymer concrete is considered eco-friendly concrete because it is free of cement. Otherwise, nanomaterials have been introduced into geopolymer concrete in previous works with the aim of improving its properties. However, very restricted studies have focused on the combined utilizing of nano-clay and nano-titanium in geopolymer concrete. Therefore, in the current research, geopolymer concrete was developed from industrial wastes (fly ash; FA) by using a novel mixture of different nanomaterials: nano-clay (NC) and nano-TiO2 (NT). Mixtures with constant water to FA (12 %), and different alkaline contents: (40 %, 45 %, and 50 %) by FA, were performed and divided into three groups. In the first group, only FA was used as a binder, meanwhile, a combination of (FA+NC) and (FA+NT) was used separately in group two (binary). In the third group, (FA+NC+NT) were mixed together (ternary). Several hardened tests have been investigated: compressive, tensile strengths and density. Also, microstructural characteristics were monitored using XRD and SEM tests. The findings revealed that the addition of nanomaterials obviously enhanced the density of the microstructure, reducing the pores of the produced geopolymer concrete. Moreover, the compressive strength was enhanced up to 38 % for NC, and 24 % for NT in the binary blends while the improvement reached 55 % in the ternary blends.

Preparation, corrosion resistance and mechanical properties of electroless Ni-W-P-eGO composite coatings

In this paper, highly dispersed edge graphene oxides (hereinafter referred to as eGO) were successfully applied in the Ni-W-P bath system, and high-performance Ni-W-P-eGO coating was prepared on the surface of N80 carbon steel by an electroless deposition method. By investigating concentration of eGO in solution in the solution, and using XPS, XRD, EDS, and SEM to analyze the crystal properties, electroless composition, micromorphology, and microstructure of the coating in detail,and the hardness, corrosion resistance and wear resistance of the coatings were investigated by microhardness tests, electrochemical corrosion and friction and wear tests. The niversal electrochemical methods determined the corrosion resistance of the coating, and the abrasion resistance of the coating was determined by ageneralduty reciprocating test. The experimental characterization results show that the addition of eGO nanomaterials to the Ni-W-P composite coating significantly improves the corrosion resistance of the coating in 3.5 wt% NaCl solution, improve the mechanical properties of the coating. When eGO content reaches 0.1 g/l, Ni-W-P-eGO coating demonstrated the most excellent corrosion resistance with a corrosion current of 0.9476 μA/cm2, and mechanical properties (the average friction coefficient is 0.173, and the microhardness value is 744.58 HV).

Enhancement of Anaerobic Digestion with Nanomaterials: A Mini Review

In recent years, the number of articles reporting the addition of nanomaterials to enhance the process of anaerobic digestion has exponentially increased. The benefits of this addition can be observed from different aspects: an increase in biogas production, enrichment of methane in biogas, elimination of foaming problems, a more stable and robust operation, absence of inhibition problems, etc. In the literature, one of the current focuses of research on this topic is the mechanism responsible for this enhancement. In this sense, several hypotheses have been formulated, with the effect on the redox potential caused by nanoparticles probably being the most accepted, although supplementation with trace materials coming from nanomaterials and the changes in microbial populations have been also highlighted. The types of nanomaterials tested for the improvement of anaerobic digestion is today very diverse, although metallic and, especially, iron-based nanoparticles, are the most frequently used. In this paper, the abovementioned aspects are systematically reviewed. Another challenge that is treated is the lack of works reported in the continuous mode of operation, which hampers the commercial use of nanoparticles in full-scale anaerobic digesters.

An overview on nanomaterials with magnetic properties used in the textile sector

Nowadays, the world of materials around us has reached a new step in evolution. New materials with amazing properties and functions are innovated in our attempt to make our lives easier and turn the world into a better place for the future. The current generation of textile materials is based on innovative technologies and modern fibres, making them smarter and more technical than ever, giving to people the possibility to adapt to the conditions and evolution of this century. Nanotechnology is a big contributor to the wide expansion of textile applications through the offered benefits and functionalities. It is used for the development of fabrics that are stronger, lighter, more durable or among others, capable of self-cleaning, self-repairing or resisting wrinkling. The addition of magnetic nanomaterials, such as iron oxide or nanoparticles to textiles, either as coatings or as composite materials or as unique elements in industrial processes (e.g., in the dyeing process, in the wastewater treatment process), opens new possibilities for the improvement and future development of the textile sector. This paper presents a summary of some of the latest developments regarding the types of magnetic nanomaterials, their functions, and applications in the textile industry and also the technologies used in different studies to manufacture textile materials with magnetic properties. Finally, the utility of the electrospinning technology to produce materials with full magnetic properties at the nano level and their usefulness in a series of applications proposed by researchers is demonstrated.

Effect of Nanosilica and Multiwalled Carbon Nanotubes on the Mechanical and Impact Performance of Unidirectional Kevlar/Epoxy Based Composites

The introduction of numerous nanoparticles into nanotechnology in recent years has opened the door for the incorporation of nanoparticles into polymeric-based composite materials for mechanical improvement. Composite materials are becoming a promising substitute material in the fabrication of numerous components due to their high weight-to-strength ratio and mechanical characteristics such as tensile Strength, flexural Strength, interlaminar shear strength, and impact strength. This research aims to determine the effect of a combined mixture of silica and multiwalled carbon nanotube particles (MWCNT) on the mechanical and impact properties of unidirectional Kevlar (UD)/epoxy composites for use in defence and aerospace applications. The addition of these Nanofillers results in high-performance reinforcement and the formation of hybrid composites with improved properties due to their use. The addition of specific nanomaterials can further enhance these characteristics, dependent on the concentration at which they are introduced into the solution. The most challenging aspects of incorporating nanomaterials into matrix materials are ensuring uniform mixing of the nanomaterials with the matrix material and increasing the viscosity of the matrix material when the nanomaterials are introduced into the matrix. Using different weight percentages, it is possible to determine the optimal ratio of nanofiller for predicting the enhanced mechanical properties of nano-composites. Preparation of the composite with different weight percentages (1 percent and 3 percent) of Nano SiO2 particles mixed with 0.25 percent MWCNT and 6 layers of the UD Kevlar fibre was accomplished using an ultrasonic vibration-assisted hand layup process. Tensile tests, Charpy impact tests, and interlaminar shear strength tests evaluated the material's mechanical properties. Experimental results revealed that tensile strength and impact strength increased by up to 80 percent and 50 percent, respectively, compared to the neat specimens. The ILSS test demonstrates a 271 percent improvement in shear strength at 3 percent and 0.25 MWCNT. The overall results determined that the combination of 3 percent SiO2 and 0.25 percent MWCNT provided the most enhanced mechanical properties while also being the most optimized. This study's findings indicate that applying a nano-silica and MWCNT mixture of Nanofillers to Kevlar fabrics is a promising method for improving a Kevlar-based hybrid composite's mechanical and impact energy absorption laminate.