Concentration Of Nanoparticles Research Articles

Mixed convective heat transfer to flexible viscosity nanofluid over a radially elongated convective exterior with temperature dependent heat source and Arrhenius activation energy

Purpose This study aims to explore the collective influence of several factors, namely, thermal radiation, Brownian motion, magnetic field and variable viscosity parameter, on the boundary layer flow, heat and mass transfer of an electrically steering nanofluid over a radially stretching exterior subjected to convective heating. In addition, the impacts of thermal and solutal buoyancy forces and activation energy are taken into account. The enlarging velocity is assumed to vary linearly with radial distance. Design/methodology/approach Through the similarity transformation technique, the governing highly nonlinear partial differential equations are transformed into a set of nonlinear ordinary differential equations, which are then numerically solved using the Runge–Kutta–Fehlberg method with a shooting technique. Findings Graphical depictions are provided to analyze the velocity, temperature and nanoparticle concentration fields under the influence of various pertinent parameters. Furthermore, local skin friction, local Nusselt and Sherwood numbers are quantitatively presented and discussed. A comparison with previous results demonstrates good agreement. Originality/value This study uniquely integrates multiple factors influencing boundary layer flow in electrically conducting nanofluids, offering a nuanced understanding of heat and mass transfer over radially stretching surfaces. By using advanced numerical methods, it provides valuable insights and quantitative data that can inform practical applications in engineering and materials science.

Nanosilver–Biopolymer–Silica Composites: Preparation, and Structural and Adsorption Analysis with Evaluation of Antimicrobial Properties

In this article, we report on the research on the synthesis of composites based on a porous, highly ordered silica material modified by a metallic nanophase and chitosan biofilm. Due to the ordered pore system of the SBA-15 silica, this material proved to be a good carrier for both the biologically active nanophase (highly dispersed silver nanoparticles, AgNPs) and the adsorption active phase (chitosan). The antimicrobial susceptibility was determined against Gram-positive Staphylococcus aureus ATCC 25923, Gram-negative bacterial strains (Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603, and Pseudomonas aeruginosa ATCC 27853), and yeast Candida albicans ATCC 90028. The zones of microbial growth inhibition correlated with the content of silver nanoparticles deposited in the composites and were the largest for C. albicans (14–21 mm) and S. aureus (12–17 mm). The suitability of the composites for the purification of water and wastewater from anionic pollutants was evaluated based on kinetic and equilibrium adsorption studies for the dye Acid Red 88. The composite with the highest amount of the chitosan component showed the greatest adsorption capacity (am) of 0.57 mmol/g and the most effective kinetics with a rate constant (log k) and half-time (t0.5) of −0.21 and 1.62 min, respectively. Due to their great practical importance, AgNP–chitosan–silica composites can aspire to be classified as functional materials combining the environmental problem with microbiological activity.

Cationic Micelle-like Nanoparticles as the Carrier of Methotrexate for Glioblastoma Treatment

In the present study, ultra-small, magnetic, oleyl amine-coated Fe3O4 nanoparticles were synthesized and stabilized with a cationic ligand, cetyltrimethylammonium bromide, and an anticancer drug, methotrexate, was incorporated into a micelle-like nanoparticle structure for glioblastoma treatment. Nanoparticles were further characterized for their physicochemical properties using spectroscopic methods. Drug incorporation efficiency, drug loading, and drug release profile of the nanoparticles were investigated. According to the results, max incorporation efficiency% of 89.5 was found for 25 µg/mL of methotrexate-loaded nanoparticles. The cumulative amount of methotrexate released reached 40% at physiological pH and 85% at a pH of 5.0 up to 12 h. The toxicity and anticancer efficacy of the nanoparticles were also studied on U87 cancer and L929 cells. IC50 concentration of nanoparticles reduced cell viability to 49% in U87 and 72% in L929 cells. The cellular uptake of nanoparticles was found to be 1.92-fold higher in U87 than in L929 cells. The total apoptosis% in U87 cells was estimated to be ~10-fold higher than what was observed in the L929 cells. Nanoparticles also inhibited the cell motility and prevented the metastasis of U87 cell lines. Overall, designed nanoparticles are a promising controlled delivery system for methotrexate to the cancer cells to achieve better therapeutic outcomes.

CO2 mitigation, energy matrices, and the performance analysis of N-evacuated tube collector (ETC)-integrated modified solar distiller for water/electricity co-generation using CQD nanoparticles

With advances in science and technology, nanofluids are the ultrafast heat transfer fluids which effectively empowers the distillation process. In this research article, N-evacuated tube collector (N-ETC)-coupled single slope solar still-equipped built-in-passive condenser and roof-top semitransparent photovoltaic (PV) module have been analyzed incorporating carbon quantum dot nanoparticles (CQD-NPs). The effect of volume concentration of nanoparticles (NPs) and packing factor ( βc) is tested to study the system performance (thermal and electrical). The use of CQD-NPs showed impressive enhancement in thermal conductivity (56.06%), Reynold's number ([Formula: see text]), evaporative (37.9%) and convective (76.94%) heat transfer coefficient even at moderate value of βc (0.67). Thermal energy efficiency and overall daily productivity is improved by 37.67% and 44.15%, respectively, using CQD-NPs. Moreover, thermal energy/exergy-based energy metrics and life cycle assessment has been performed for different lifespans ( n = 1 to 50 years) of the proposed system. Significant improvement in life cycle conversion efficiency [31.90% ( βc = 0), 28.91% ( βc = 0.67), 24.56% ( βc = 0.75), 32.02% ( βc = 0.85), 53.38% ( βc = 0.95)] is observed; also, enviro-economic analysis showed effective rise in annual CO2 mitigation (tons) [41.39 ( βc = 0), 104.85 ( βc = 0.67), 96.23 ( βc = 0.75), 85.14 ( βc = 0.85), 65.51 ( βc = 0.95)] and carbon credits earned using CQD-NPs. This renewable stand-alone two-in-one output system effectively meet the drinking water and electrical energy requirements of societies, and families living in arid/semiarid regions.

Investigation of Al₂O₃:Cu Hybrid Nanofluid Composition in Jet Impingement Cooling: Numerical Analysis

Hybrid nanofluids have emerged as a promising medium for enhancing heat transfer in various cooling systems, particularly in jet impingement cooling applications. This study conducts a numerical analysis of the heat transfer performance of aluminium oxide (Al₂O₃) and copper (Cu) hybrid nanofluids at different mixing ratios (25:75, 50:50, and 75:25) under jet impingement cooling conditions. The research employs computational fluid dynamics (CFD) simulations to investigate the thermophysical properties and heat transfer behaviour of these hybrid nanofluids at a constant nanoparticle concentration of 0.5% by volume. Among the tested compositions, the 50:50 Al₂O₃ mixture demonstrated the highest heat transfer coefficient and surface temperature reduction, improving heat transfer by up to 22.20% compared to pure water. The findings suggest that the balanced thermal properties of this ratio has optimized cooling performance, making it suitable for industrial cooling applications, such as electronics and power systems, where efficient heat dissipation is critical.

Synergistic Effect of Iron and Zinc Nanoparticles with Recommended Nitrogen Dose on Production and Grain Quality of Maize (Zea mays L.) Cultivars Under Drought Stress

Abiotic factors, such as drought, can significantly impact the vegetative growth and productivity of maize. To investigate the effects of the combined foliar application of zinc (Zn) and iron (Fe) nanoparticles with the recommended nitrogen dose (RND) on maize production and grain chemical composition under different water regimes, two field experiments were conducted in El-Ayyat city, Giza, Egypt, during the summer seasons of 2022 and 2023. This study utilized a split-split-plot experimental design with three replications. The main plots were designated to different water regimes (100, 80, 60, and 40% of estimated evapotranspiration), while the sub-plots were randomly distributed with Zn and Fe nanoparticle concentrations (0, 100, and 200 mg/L). The sub-sub-plots were randomly allocated to three maize cultivars (SC-P3062, SC-32D99, and SC-P3433). The results revealed that exposure to drought conditions resulted in a significant decline in the yield and yield-related attributes across all maize cultivars examined. Grain yield decreased by 10–50% under drought conditions. However, the foliar application of Zn and Fe nanoparticles was found to significantly improve grain yield, protein content, oil content, starch content, crude fiber, ash, and macro- and micronutrient concentrations in the maize cultivars under control and drought stress conditions. The foliar application of Zn and Fe nanoparticles at a concentration of 200 mg/L to the SC-P3433 maize cultivar led to the greatest grain yield per hectare, reaching 11,749 and 11,657 kg under the irrigation regimes with 100 and 80% total evapotranspiration, respectively. According to the assessment using the relative drought index, the SC-P3062 maize cultivar demonstrated tolerance (T) to water stress conditions. In conclusion, the foliar application of Zn and Fe nanoparticles (100–200 mg/L) effectively mitigated the negative effects of drought stress on maize plants. This approach can be recommended for farmers in arid and semi-arid regions to maintain and improve maize yield and grain quality under water-deficit conditions.

Thermal and Flow Characteristics of Alumina Nanofluids in Microfluidic Systems: A Low-Concentration Study

Microfluidic technologies and nanofluids represent a synergistic combination with significant potential for enhancing heat transfer and thermal management applications. This study investigates the thermal and flow characteristics of a 0.001 wt.% alumina (Al₂O₃)-water nanofluid within a custom-designed serpentine microfluidic channel. The nanofluid was prepared and characterized for its thermal conductivity, viscosity, specific heat, and density. Experimental microfluidic studies, supplemented by numerical simulations, were conducted to evaluate the fluid's behavior under controlled conditions. Results indicated a slight increase in thermal conductivity for the Al₂O₃ nanofluid compared to pure water, with increments ranging from 0.16% at 20°C to 0.30% at 80°C, attributed to enhanced Brownian motion of the nanoparticles. Viscosity measurements revealed marginal increases, suggesting minimal impact on fluid flow dynamics. The microfluidic experiments demonstrated a consistent pressure gradient and laminar flow regime, essential for precise control and efficient thermal management. Temperature contours showed effective heat dissipation, with a steady thermal gradient from the inlet to the outlet. The study concludes that low-concentration Al₂O₃ nanofluids can enhance thermal performance in microfluidic systems without significantly affecting flow characteristics, making them suitable for applications requiring efficient heat dissipation, such as electronic cooling and chemical reactions. These findings provide a foundation for future research into higher nanoparticle concentrations and different base fluids, aimed at optimizing the thermal and flow properties of nanofluids in microfluidic environments. The integration of nanofluids with microfluidic technologies holds promise for advancing the performance and reliability of next-generation thermal management systems.

Evaluation of a micro-particle-enhanced phase-change material integrated heat pipe evacuated tube solar collector system using lanthanum oxide/water nanofluid

ABSTRACT In this study, the thermal performance of a microparticle-enhanced form-stable phase change material (PCM) integrated heat pipe evacuated tube solar collector (ETSC) system is evaluated through outdoor experimentation. The study examines the thermal performance of PCM-enhanced ETSC using acetamide with varying percentages of expanded graphite (EG) at 10, 15, and 20 wt% and aluminum microparticles at 1, 2, and 5 wt%, focusing on the use of EG at different concentrations and microparticles. The microparticle-enhanced form-stable PCM is integrated into the tube only. The system was tested under open environmental conditions, comparing outcomes with a normal ETSC system, considering water outlet temperature, charging-discharging behaviors, collector efficiency, and energy analysis. The study revealed that the micro-particle enhanced PCM integrated heat pipe ETSC system significantly improved thermal performance, energy storage and release capabilities, and efficiency in generating heat at lower solar irradiance, compared to conventional ETC systems. The maximum collector efficiency of 47.4% is achieved when utilizing acetamide with 10% EG and 2% Al, which is 10.9% more than conventional ETSC. The study explores the use of lanthanum oxide/water nanofluid in solar collectors, revealing that increasing nanoparticle concentrations enhances water outlet temperature, heat gain, and solar thermal collector efficiency up to 64.14%.

Effect of nano titanium and organic fertilizer on broccoli growth, production, and biochemical profiles

Broccoli is considered a highly valuable vegetable due to its significant enrichment with health-promoting biochemicals. A greenhouse experiment was conducted to evaluate the responses of broccoli plants to different concentrations of titanium dioxide nanoparticles (TiO2NPs) applied via foliar spray and organic fertilizer (OF) applied to the soil. The results revealed that 40 mg/L TiO2NPs had the greatest effect on leaf dry matter (16.38%), total polyphenolic content (39.77 μg GAE/g FM), nitrogen (1.93%), and phosphorus content (0.35%) compared to the control and other treatments. OF applied at 30 L/ha improved the chlorophyll content (1.99 μg/g FM). Furthermore, vegetative and root growth, fruit characteristics, and potassium content were significantly influenced by the interaction of 20 mg/L TiO2NPs with 15 L/ha OF. The combination of 20 mg/L TiO2NPs with 30 L/ha OF resulted in the most significant increase in root diameter (8.77 mm), chlorophyll b (0.40 μg/g FM), carotenoid (0.50 μg/g FM), and total flavonoid content (4.56 μg QE/g FM) compared to control plants and single effect of TiO2NPs and OF. The combination of 40 mg/L TiO2NPs with 15 L/ha OF increased the number of roots (21.84), and 40 mg/L TiO2NPs with 30 L/ha OF significantly increased total soluble solids (7.85°Brix) and DPPH free radical scavenging activity (5.12 μg/g FM). This study established that TiO2NPs were more effective for enhancing broccoli plant growth when applied in combination with OF and can be recommended for use in sustainable agriculture, particularly at the interaction of 20 mg/L TiO2NPs with 15 and 30 L/ha OF.

Analysis on the Propagation and Assembly of Metallic Nanoparticles through Subwavelength Apertures with Overlapping Electrical Double Layers.

Hybrid nanoplasmonic structures composed of subwavelength apertures in metallic films and nanoparticles have recently been demonstrated as ultrasensitive plasmonic sensors. This work investigates the electrokinetically driven propagation of the assembly mechanism of the metallic nanoparticles through nanoapertures. The Debye-Hückel approximation for a symmetric electrolyte solution with overlapping electrical double layers (EDLs) is used to obtain an analytical solution to the problem. The long-term silver nanoparticle concentration response is derived using the homogenization method and a multiscale analysis. The results indicate that uncharged nanoparticles will flow through the nanohole array if the nanochannel height is larger than the Debye length (h 0 > λD), while a trapping mechanism occurs, due to the overlapping of the EDL, when h 0 ∼ 3.8λD. For charged nanoparticles, the response to the electric field occurs locally with the walls of the nanochannel, regardless of its height. For a critical value of the nanochannel length, the leading order of the concentration field becomes purely diffusive.

Investigating the effect of an inclined magnetic fieldon heat and mass transmission in turbulent squeeze flowof UCM fluid between parallel plates

This paper investigates the effects of an inclined magnetic field on heat and mass transfer in turbulent squeeze flow of a viscoelastic fluid with an upper-convected Maxwell model. Squeezing flow is an important phenomenon in various industrial and mechanical processes related to flows between parallel surfaces. Mathematical modelling for the law of conservation of mass, momentum, heat and concentration of nanoparticles is executed. The study employs a system of partial differential equations to describe the flow issue. Governing nonlinear partial equations are reduced into nonlinear ordinary differential equations. The modelled equations are then solved numerically by utilizing the efficient Adams-Moulton method of the fourth order based on the shooting technique using the Fortran programming language. Numerical results are compared with another numerical approach and an excellent agreement is observed. The effects of various factors on the non-dimensional velocity, temperature, and concentration patterns are presented using graphs, while tables are used to assess the numerical values of the skin friction, Nusselt and Sherwood numbers. It is found that the temperature profile decreases as the compression parameter increases but increases with an increase in the Eckert number. The results of this study could be useful in designing heat and mass transfer equipment for applications in viscoelastic fluid flows under an inclined magnetic field.

Thermal Performance Optimization of Nano-Enhanced Phase Change Material-Based Heat Pipe Using Combined Artificial Neural Network and Genetic Algorithm Approach

Abstract The present study focuses on the numerical investigation of nano-enhanced phase change material (Ne-PCM)-based heat pipes designed for electronic cooling applications. It uses both paraffin wax and n-eicosane as phase change materials (PCMs) that are combined with copper oxide (CuO) nanoparticles at different concentrations of 1%, 3%, 5%, and 7%. The heat input to the heat pipe ranges from 10 to 50 W in an increment of 10 W to simulate realistic operating conditions. The idea is to predict the heat pipe's thermal performance at various combinations of nanoparticles and PCMs and compare the same to the baseline case of deionized (DI) water (without PCM). The results show a constant drop in the evaporator temperature for the Ne-PCM-assisted heat pipes. Paraffin wax and n-eicosane exhibit maximum reductions of 2.86% and 1.94%, respectively, in evaporator wall temperature compared to using conventional DI water (without PCM). The thermal resistance of the heat pipe also decreases consistently with increasing the heat input for all cases, with the most significant reduction of 33.11% and 16.63% for paraffin wax–CuO- and n-eicosane–CuO-assisted heat pipes, respectively. The maximum evaporator heat transfer coefficients recorded are 257.79 W/m2K, 353 W/m2K, and 265.18 W/m2K for heat pipes using DI water (without PCM), paraffin wax–CuO, and n-eicosane–CuO, respectively. The nanoparticles act as a thermal conductivity enhancer and bring down the heat pipe's evaporator temperature with the addition of PCMs. Thus, the effective thermal conductivity of the Ne-PCM-based heat pipe is notably higher compared to heat pipes using DI water (without PCM). To understand the complex thermal behavior of the Ne-PCM-based heat pipes and to better predict their thermal performance, a predictive model has been developed using an artificial neural network (ANN). This model drives the genetic algorithm (GA) that considers the multivariable interaction of PCMs and nanoparticle concentrations to identify the optimal configuration and results in better thermal performance of the heat pipe. Thus, the combination of ANN and GA aids a useful approach for the effective prediction of the heat pipe's thermal performance. The outcomes of this study are useful for the development of sustainable solutions in electronic cooling applications.

Effect of Concentration of TiO2 Nanoparticles on Thiadiazole Derivative and Their Molecular Docking Study.

In the present work, we report the synthesis of TiO2 nanoparticles by hydrothermal method using titanium isopropoxide. The synthesized TiO2 nanoparticles were investigated by Powder X-ray diffraction, FE-SEM with EDX, Photoluminescence, UV-Visible absorption and Fluorescence emission spectroscopy. Fluorescence intensity and absorption values of 4-[5-(2,5-Dimethyl-pyrrol-1-yl)-[1,3,4]thiadiazol-2-ylsulfanylmethyl]-6-methoxy-chromen-2-one (DTYMC) molecule decreases with adding the concentration of TiO2 nanoparticles. Stern-Volmer equation for steady state method is found to be linear and its co-relation coefficient is found to be r = 0.88, which indicates the presence of dynamic quenching. Binding orientations of the DTYMC ligand with targeted proteins are Thymidylate synthase (TS) - PDB ID: 1JU6, The type II topoisomerases (TOP2α) - PDB ID: 4FM9 and Human thymidine phosphorylase (hTP) - PDB ID: 2WK6. The obtained result suggests that, the DTYMC molecule exhibits inhibitory activity against the overexpression of TS receptor which causes non-small cell lung cancer (NSCLC). Antimicrobial study of TiO2 NPs has been determined.

Synergetic Effect of Zinc Oxide and Zirconium Oxide Nanoparticles Concentrations on Antifungal and Physical Properties of Polymethyl Methacrylate Resin (PMMA)–An Invitro Analysis

Synergetic Effect of Zinc Oxide and Zirconium Oxide Nanoparticles Concentrations on Antifungal and Physical Properties of Polymethyl Methacrylate Resin (PMMA)–An Invitro Analysis

Interaction of induced magnetic field, double diffusion convection and multiple slips for thermal radiative biological flow of six-constant Jeffreys nanofluid: Advancements in mechanics

ABSTRACT The mathematical modeling of biological fluids holds paramount importance, given its diverse applications in the medical field. Understanding the peristaltic mechanism is crucial for gaining insights into various biological flows. This study focuses on numerically estimating the double-diffusive peristaltic flow of a non-Newtonian six constant Jefferys nanofluid within an irregular medium. The investigation considers the influences of nonlinear thermal emission, viscous dissolution, and induced magnetization, incorporating multiple slip conditions. The Buongiorno model is employed to underscore key features related to thermophoresis and Brownian diffusion coefficients. The convection of double diffusivity is elucidated through the Soret and Dufour variables. Lubrication technique is employed for mathematical simulation, and the resulting nonlinear coupled system of differential equations is solved numerically through the Mathematica program’s built-in command (ND Solve function). The graphical representation of the impact of crucial flow variables, such as nanoparticle volume proportion, pressure gradient, solute density, temperature, pressure fluctuation per wavelength, and velocity distribution, provides valuable insight. The findings of the current study show that an increase in the Prandtl number and thermophoresis parameter leads to the expansion of thermal curves. Moreover, it is also noted that rising heat frequencies of radiation cause the concentration of nanoparticles to increase.

Evaluation of the impact of oleic acid-capped Al2O3 nanoparticles on the tribological performance of conventional lube oil

Purpose This study aims to evaluate the influence of oleic acid (OA)-capped Al2O3 nanoparticles on the tribological performance of conventional lube oil. The goal is to determine the optimal nanoparticle concentration that enhances lubricant efficiency by reducing friction and wear. Design/methodology/approach The research involved preparing nanolubricants with four different concentrations of Al2O3 nanoparticles: 0.05, 0.1, 0.25 and 0.5 wt.%. Tribological performance was assessed using a four-ball tribotester, which measured the coefficient of friction (COF) and wear scar diameter (WSD) under standardized testing conditions. Findings The experimental results revealed that the nanolubricant containing 0.1 wt.% OA-Al2O3 nanoparticles exhibited the most significant improvement in tribological performance. This formulation achieved a 38.84% reduction in COF and a 23.87% reduction in WSD compared to the base lubricant. These findings demonstrate the effectiveness of incorporating OA-capped Al2O3 nanoparticles in reducing friction and wear, thereby enhancing the overall performance of conventional lubricants. Originality/value This study demonstrates the benefits of OA-capped Al2O3 nanoparticles in lubricants, including a 38.84% reduction in COF and a 23.87% reduction in WSD. By systematically analyzing different nanoparticle concentrations, it identified that 0.1% by weight of nanoparticles is the most effective formulation for reducing friction and wear. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0236/

One-Step Synthesis of Antimicrobial Polypeptide-Selenium Nanoparticles Exhibiting Broad-Spectrum Efficacy against Bacteria and Fungi with Superior Resistance Prevention.

The growing threat of antimicrobial resistance (AMR) necessitates innovative strategies beyond conventional antibiotics. In response, we developed a rapid one-step method to sythesize antimicrobial peptide (AMP) ε-poly-L-lysine stabilized selenium nanoparticles (ε-PL-Se NPs). These polycrystalline NPs with highly positive net surface charges, exhibited superior antimicrobial activity against a broad panel of pathogens, including the Gram-positive and -negative bacteria Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa and their drug-resistant counterparts, as well as the yeast Candida albicans. Notably, 10PL-Se NPs exhibited 6-log reduction of methicillin-resistant S. aureus (MRSA) at a concentration of 5 μg/mL within 90 min, with minimum bactericidal concentrations (MBCs) below 50 μg/mL for all tested bacterial strains. The minimum fungicidal concentration (MFC) of 10PL-Se NPs against C. albicans was 26 ± 10 μg/mL. Crucially, bacteria exposed to ε-PL-Se NPs exhibited significantly delayed resistance development compared to the conventional antibiotic kanamycin. S. aureus developed resistance to kanamycin after ∼72 generations, whereas resistance to 10PL-Se NPs emerged after ∼216 generations. Remarkably, E. coli showed resistance to kanamycin after ∼39 generations but failed to develop resistance to 10PL-Se NPs even after 300 generations. This work highlights the synergistic interactions between ε-PL and Se NPs, offering a robust and scalable strategy to combat AMR.

Enhanced dust reduction method for solar panels application

Introducing an innovative dual-layer coating technique to enhance solar panel durability against dust, this method uses a translucent aluminum zinc oxide conductive film to prevent accumulation through active dust repulsion. A secondary TiO2-infused coating, applied via a cost-effective sol-gel method, boosts anti-soiling capabilities in a passive manner. Comprehensive tests on dust accumulation, self-cleaning efficiency, mechanical robustness, UV-VIS transmission, and chemical resilience reveal promising results. These coatings improve glass clarity, reduce dust adhesion, and maintain energy production even in calm conditions. The effectiveness relies on the precise concentrations of aluminum nitrate and Titania nanoparticles, with annealing temperature affecting transmission rates. The coatings demonstrate highly desired resistance to both alkaline and acidic environments, ensuring consistent performance across various settings. This durability supports the widespread adoption of solar energy in diverse climates, advancing global sustainable energy efforts.

Extraction of Lignin from Duabanga grandiflora and its Valorization for Nanocomposite Development with Enhanced Mechanical and UV Shielding Properties

Abstract In this study, we report on extracting lignin (EL) from Duabanga grandiflora (Khukon), an untapped wood source, and its transformation into nano-lignin (NL) to create durable and thermally stable composites. Utilizing ultrasonication, we synthesized spherical lignin nanoparticles with an average size of 8 nm, as verified by High-Resolution Transmission Electron Microscopy (HRTEM). These nanoparticles were integrated into a polyvinyl alcohol (PVA) and guar gum (GG) matrix, resulting in PVA-GG-nano-lignin (PGNL) composites. Polyvinyl alcohol (PVA)-Guar gum (GG) nanocomposite films containing various contents of lignin nano-particles (1, 2 and 3 wt%) were formulated by a simple solvent cast method and cross-linked by adding borax. Addition of 1wt% lignin nanoparticles brought in the composite films with 29.8MPa tensile strength and 139.3% elongation at break. Compared to PVA-GG-lignin (PGL) composites, the PGNL composites exhibited a 59.4% increase in tensile strength and enhanced elongation at break and good thermal degradation properties. Notably, the PGNL composite films were transparent but could shield 99.9% of the UV-A (320-400 nm) and UV-B (280-320 nm) radiations, marking a significant advancement in UV protective materials. Our innovative use of Duabanga grandiflora-derived nano-lignin in a dual-polymer network not only underscores the potential of renewable resources in high-performance applications but also aligns with the principles of a circular bioeconomy by offering a sustainable solution for effective UV protection.

Chemical and thermal stability of different AgNP concentrations incorporated in 0.1% DMPT UPE resin

Purpose In response to the growing demand for a polymer with improved chemical and thermal stability in the construction sector, this study aims to thoroughly explore the characteristics of silver nanoparticles (AgNP) and their various concentrations. The primary goal is to determine the effect of these nanoparticles on the chemical and thermal stability of unsaturated polyester (UPE) resin doped with dimethyl-para-toluidine (DMPT) when exposed to high temperatures. Design/methodology/approach Silver nanoparticles were first synthesized from the chemical reaction between silver nitrate and trisodium citrate before its addition to the resin. The nanocomposites were thoroughly examined using advanced analytical methods such as Fourier transform (FTIR), Raman spectroscopy and scanning electron microscope to determine chemical stability. Thermal stability tests were carried out using thermogravimetric analysis, differential thermal analysis and derivative thermogravimetry methods; viscosity and peak exotherm were also examined. Findings The data shows that increasing nanoparticle concentration improves resin chemical stability, reduces peak exotherm duration and increases viscosity. Clearly, only 1.5% AgNP concentration outperformed neat UPE resin, while 0.5% and 1% AgNP concentrations fall short in terms of thermal stability. Originality/value The enhanced resin highlights the subtle influence of nanoparticle addition, which has a greater impact on the chemical structure of the composite rather than its thermal properties.