This research investigates the green synthesis of gold nanoparticles (Au NPs) using a biodegradable and natural reducing agent, arabinoxylan mucilage from Plantago major seeds. UV-Vis spectroscopy revealed a characteristic surface plasmon resonance peak at 550 nm, with an energy band gap of 3.45 eV, confirming Au NP formation. FTIR analysis revealed peaks corresponding to alcohol, carbonyl, and other functional groups, along with a distinct metal-oxygen bond signal, demonstrating the participation of the groups in NP stabilization. SEM revealed globular-shaped particles (78 nm), while EDX analysis confirmed the elemental composition. XRD patterns verified the crystalline NPs with a face-centered cubic structure. The Au NPs exhibited effective microbicidal potential against Escherichia coli (ZOI 25 ± 0.66 mm), Bacillus cereus (ZOI 18 ± 0.33 mm), and Enterobacter aerogenes (ZOI 11 ± 0.98 mm). The significant minimum inhibitory and bactericidal concentrations (MICs and MBCs) were investigated for bacterial strains, confirming the antimicrobial potential of Au NPs. Furthermore, the Au NPs demonstrated remarkable photocatalytic performance with degradation efficiencies of 89% for methylene blue (MB) and 81.19% for methyl orange (MO) under pseudo-first-order kinetics, highlighting their potential for wastewater treatment.
The green synthesis pathway is cost-effective, environmentally benign (using non-toxic materials), and frequently produces better results than traditional methods. In the current study, an extract from a by-product such as the peel of Opuntia ficus indica (OFI) fruits was used in an improved phyto-synthesis process to create TiO2 nanoparticles (NPs). With the aid of stabilizing molecules found in the extract, titanium isopropoxide (TiTP) functions as a precursor of titanium to create TiO2 NPs. To characterize the appearance and structure of the synthesized nanoparticles, a range of analytical methods was utilized. The techniques employed encompassed X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and ultraviolet-visible spectroscopy (UV-Vis), in addition to scanning electron microscopy paired with energy dispersive X-ray spectroscopy (SEM with EDX) and zeta potential analysis. Gram-positive Bacillus subtilis and Gram-negative Escherichia coli and Pseudomonas aeruginosa bacteria were effectively inhibited by the as-prepared TiO2. Nanoparticles prepared by this phyto-synthesis method may be thus suitable for a wide range of biological and medicinal applications.
This study explores the effects of nano alumina and surface treatment on the physical and mechanical performance of areca palm stem (APS) fiber reinforced epoxy composites. The composite samples were prepared using the conventional hand layup method, maintaining a constant APS fiber content of 20 wt%, while varying sodium hydroxide concentrations (0%, 3%, 6%, and 9%) and nano alumina filler loadings (0 wt%, 2.5 wt%, 5 wt%, and 7.5 wt%). This study demonstrates that incorporating alumina nanofillers and sodium hydroxide treatment of fibers can enhance the mechanical properties of APS fiber reinforced composites. The incorporation of alumina nanoparticles into treated composites enhanced elasticity, toughness, strength, ductility, and hardness as the nanofiller concentration increased up to 5 wt%. Compared to untreated composites, incorporating 6% sodium hydroxide treated areca fibers and 5 wt% nanofillers leads to a 53.60% improvement in tensile strength and a 43.05% improvement in flexural strength. The maximum impact energy (5.81 J) and hardness (59.5 HV) are achieved at 7.5 wt% nano alumina reinforced APS fiber composites treated with 6% sodium hydroxide. Morphological analysis conducted with a scanning electron microscope revealed various defects such as fiber pull-outs, interfacial behaviour issues, internal cracks, and voids.
The objective of this study was to develop fire-resistant paper by immersing commercial paper samples into various fire-retardant chemical solutions. In the experimental work, untreated commercial papers were treated with fire-retardant chemicals boric acid (BA), borax (BX), and aluminum hydroxide (AH) at different concentrations. The papers were impregnated for a fixed duration using the impregnation method, and following drying under controlled conditions, their weight, thickness, thermal stability (TGA), limiting oxygen index (LOI), and printability were evaluated in accordance with relevant standards. The results revealed that impregnation increased both paper weight and thickness, whereas the liquid-penetration behavior was strongly dependent on the flame-retardant type, concentration, and immersion frequency, with low-concentration BA and BX treatments and repeated AH treatments generally providing improved resistance to water penetration. However, the TGA analysis indicated an increase in residual mass. Furthermore, the LOI test demonstrated that papers treated with BA and BX could be classified as fire-resistant, and the printing tests confirmed an improvement in print quality.
Excessive hemorrhage poses a significant risk, necessitating the development of effective hemostatic agents. However, commercially available products often suffer from poor biocompatibility and biodegradability. This study presented a composite particle material combining water-soluble oxidized regenerated cellulose dialdehyde (ORCdial) and chitosan to enhance hemostatic efficacy and biocompatibility. It was hypothesized that ORCdial formed a gel upon blood contact, while chitosan interacted with the coagulation cascade, making them promising candidates for hemostasis. Particles were synthesized by blending ORCdial and chitosan, lyophilizing, neutralizing, and milling the mixture into particles. Crosslinking was confirmed by FTIR (C=N band at ~1640–1655 cm⁻¹) and solid-state ¹³C CP/MAS NMR (imine carbon at ~165–170 ppm). Their physicochemical properties and hemostatic performance were evaluated in vitro. In vitro studies demonstrated that ORCdial-chitosan composites significantly improved clotting efficiency and cell compatibility compared to the commercial hemostatic agent Celox®, with performance varying based on ORCdial content. In conclusion, this study presented a novel, biocompatible, and effective hemostatic material with promising in vitro hemostatic performance, offering a potential candidate for further pre-clinical investigation in hemorrhage control.
This research study focused on the impacts of some crucial process variables on the single-stage hydrogen peroxide bleaching of recycled deinked pulp. The impacts of hydrogen peroxide and sodium hydroxide doses, temperature, retention time, pulp consistency, and sodium silicate addition were analyzed systematically. The results obtained indicated that an increase in the dose of peroxide increases the brightness and reduces absorption; however, excess doses result in yield loss, without improving the performance further. Sodium hydroxide is vital for the activation of peroxide, with an optimal range of 1.50–2.00% leading to maximum brightness and higher doses promoting alkaline darkening. Temperature and time have high impact on the bleaching performance; optimal values of 70 °C and 3 h retention give the best combination of brightness and yield. Pulp consistency of medium (10.00%) value is the most advantageous for achieving effective use of chemicals, in contrast to lower and higher consistencies. The addition of sodium silicate (2.00–3.00%) stabilized peroxide, increased scattering effect, and prevented ink redeposition. Overall, the optimization of chemicals and process variables considerably improves the brightness and optical characteristics of recycled deinked pulp. Single-stage peroxide bleaching of recycled deinked pulp yielded pulp brightness of 65.00% ISO, with a yield of 95.20%.
This article presents the results of a study of the sulfation of bactoagar with sulfamic acid in the presence of urea. The aim of the work was to study the effect of reaction conditions (temperature and duration) on the yield of the sulfated product and the sulfur content in it. Optimum conditions for sulfation were determined as a temperature of 85–90 °C and a reaction duration of 3 hours, which ensures the maximum yield of the product (92%) and high sulfur content (15.40%). The obtained sulfated samples were analyzed using NMR, FTIR spectroscopy, X-ray diffraction, atomic force microscopy, gel permeation chromatography and thermal analysis. The results of FTIR and NMR spectroscopy confirmed the successful introduction of sulfate groups into the bactoagar macromolecule, and X-ray diffraction showed an increase in the amorphous structure after sulfation. Thermal analysis revealed a decrease in the thermal stability of sulfated bactoagar compared to the original sample. The obtained data demonstrate the potential for the use of sulfated bactoagar in various fields, including biotechnology, pharmacology and drug delivery systems.
Body armor plays a crucial role in modern defense and law enforcement, offering lifesaving protection against ballistic threats. With the growing complexity of threats and the demand for improved wearer mobility, research has shifted toward optimizing materials for higher strength-to-weight ratios, enhanced energy absorption, and flexibility. This review comprehensively examines advancements in both natural and synthetic fibers used in soft and hard ballistic armor systems. Focus is given to their mechanical properties, structural configurations, and the incorporation of novel technologies, such as hybrid composites. The role of fabric architecture, surface treatments, and fiber-matrix adhesion in enhancing energy absorption is also discussed. The article concludes with future directions for the development of multifunctional, lightweight, and eco-friendly ballistic protection systems using emerging material technologies.
This study aimed to develop and optimize an extended-release (ER) metformin hydrochloride matrix tablet using hypromellose as the matrix-forming polymer. ER formulations of metformin are crucial as they provide stable plasma concentrations, reduce dosing frequency and gastrointestinal side effects, enhancing patient adherence and glycemic control. A D-optimal experimental design combined with response surface methodology (RSM) was used to evaluate the impact of formulation variables (povidone K30, hypromellose, and lactose monohydrate) on tablet properties, such as friability, hardness, flowability, and moisture content. The optimal formulation containing povidone K30 (3.38%), hypromellose (19.6%) and lactose monohydrate (35.01%) exhibited drug release following the Korsmeyer Peppas model, with 78% of the drug released over 8 hours, showing extended-release behavior. Fourier-transform infrared spectroscopy indicated no significant chemical interaction between metformin and the excipients, while X-ray diffraction showed that metformin retained its crystalline structure. DSC–TGA analysis further confirmed the stability of metformin and its compatibility with the excipients. This optimized extended-release formulation may represent a simple, cost-effective, and practical alternative for diabetes management in resource-limited settings, owing to its straightforward preparation process and the absence of requirements for specialized manufacturing technology.
Valorizing agricultural pruning residue is a sustainable way to produce in-demand, bio-based materials and reduce environmental issues related to the disposal and incineration of agricultural waste. In this context, our work focuses on the valorization of Citrus aurantium pruning waste through cellulose isolation. First, the chemical composition of the biomass was evaluated according to TAPPI standards, revealing a high content of holocellulose and α-cellulose (60.7 ± 3.06, 37.2 ± 1.76, respectively), promoting its suitability as a cellulose feedstock. The isolation process consisted of alkaline delignification, followed by sodium chlorite and acetate buffer bleaching treatment. The resulting material was characterized by evaluating its crystallinity, thermal stability and morphology. The XRD analysis revealed a crystallinity index of 68%, indicating a well preserved crystalline cellulose structure. The TGA demonstrated a major degradation peak at 350 °C and low residual mass consistent with the measured ash content. Morphological study revealed well individualized fibers with average length of 0.926 mm and width of 22 µm, and a moderate fine elements fraction. These results confirm that Citrus aurantium pruning waste is promising as alternative lignocellulosic feedstock for cellulose production, highlighting its potential for applications in biobased material fields.
Many automotive and aerospace industries have shown increasing interest in the manufacture of components from natural fiber composites due to their unique properties, such as low density, low processing cost, biodegradability, recyclability, and tailorable mechanical properties, compared to the synthetic fiber composites. In this context, Alstonia macrophylla (ASM) fiber reinforced polypropylene (ASM/PP) composites were fabricated using the hot-pressing technique. The main focus of this study was to investigate the effect of fiber content on the vibration and damping properties of the ASM/PP composites. ASM fiber was reinforced into PP on volume fraction basis ranging from 0 to 50 vol% in increments of 10 vol%. The resulting composites were designated as Neat PP, A10, A20, A30, A40 and A50 composites, respectively. Free vibration test results revealed that the addition of 40 vol% of ASM fiber into PP enhanced the natural frequency (Mode-I) of the composites. However, at lower fiber content, natural frequency of the ASM/PP composites was reduced due to the softening effect dominated by the PP matrix. Highest damping ratio was exhibited by A30 composites, however beyond 30 vol%, a significant drop in damping ratio was observed. This may be owing to poor agglomeration of the fibers at higher concentration. Experimental results were found to be in good agreement with numerical results obtained from Abaqus simulations, with an error limited to 2.28%. CAE models of the specimens were prepared as per their actual dimension. However, for enhancing effectiveness of the simulation results, the mass of the accelerometer was considered. FESEM analysis on the fractured surface supported the improvement in damping and stiffness properties.
This study investigates the non-isothermal microwave-assisted torrefaction of oil palm fibre, focusing on the effect of microwave power levels on reaction kinetics and biochar yield. Microwave-assisted torrefaction (MAT) offers rapid volumetric heating and energy efficiency, making it a promising alternative to conventional thermal methods for biomass valorization. A modified kinetic model based on di Blasi and Lanzetta was applied to simulate the decomposition pathway, incorporating heating rate (β) and multi-step reactions involving biomass (A), intermediate product (B), final product (C), and volatile components (V1, V2). Experimental data revealed that increasing microwave power from 400 W to 800 W enhanced heating rates and volatile release, but reduced solid residue yield, indicating intensified thermal decomposition. The kinetic parameters and statistical validation (R², RMSE, SSE) confirmed the model’s robustness, particularly at 400 W. These findings demonstrate that MAT can be tuned to optimize biochar properties for multifunctional applications, such as carbon sequestration and thermal energy storage, contributing to climate mitigation and sustainable biomass utilization.
Lignin has a three-dimensional amorphous network structure and hydrophilic functional groups, which make it suitable for the removal of Mo(VI) ions from contaminated aqueous environments. The optimal adsorption conditions were previously established by performing a series of experiments. These experiments targeted the mass of lignin (the adsorbent), the concentrations of Mo(VI) in aqueous environments, the initial pH of the aqueous solution of molybdenum and lignin, and the interphase contact time. In this work, Sarkanda grass lignin was evaluated as an adsorption material for Mo(VI) through a series of characterization analyses, including energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric (TG) and derivative-thermogravimetric (DTG) analyses. The state of chemical equilibrium was described by evaluating several thermodynamic parameters, including enthalpy, entropy, Gibbs free energy, and experimental adsorption isotherms. These parameters were interpreted using the Freundlich and Langmuir models. The kinetics of the process were explained by applying the Lagergren I and Ho-McKay II mathematical models. The assessment of biostability was conducted through the implementation of germination tests on white cabbage seeds (late variety – Brassica oleracea L. var. Capitata alba). These seeds were introduced into lignin that had been contaminated with Mo(VI), and the filtrates resulting from phase isolation were also examined. The data obtained suggest the potential application of Sarkanda grass lignin in the adsorption of Mo(VI) from aqueous media within the established experimental parameters. This analysis underscores several salient advantages, including the favorable mass ratio and interphase time, a straightforward working technique, the abundance and regenerability of the resource, its economic viability, and its biocompatibility.
The accumulation of agricultural waste is a serious concern worldwide. The primary goal of this paper is to examine the microstructure, thermal, mechanical and rheological properties of sugarcane bagasse and sawdust reinforced hybrid composites. Poly(3-hydoxybutyrate-co-3-hydroxyhexanoate) was employed as a polymer matrix phase, and the composites were prepared by melt extrusion at 178.8 rpm using a twin-screw extruder. The morphological features show poor interfacial adhesion between the polymer matrix and sugarcane bagasse, but sawdust shows better dispersion in the matrix. The hybrid composite comprising halloysite clay showed higher thermal stability and viscosity than all other composites. All composites showed better stiffness than the neat matrix, irrespectively of the type of reinforcing filler. The results showed that the combination of sugarcane bagasse, sawdust and halloysite clay is useful for improving the thermal stability and stiffness of the polymer matrix. This enhancement is particularly advantageous for advanced applications, such as smart packaging solutions and electronics, where the interplay of thermal properties and rigidity is important.
This paper introduces a sustainable circular-economy plan of transforming waste cotton fabric into useful carbon materials through controlled pyrolysis and assesses their application as epoxy composite strengthening agent. Scanning electron microscopy and Raman spectroscopy confirmed that the semi-graphitic carbon had retained the fibrous morphology and porous surfaces of the cotton precursor. Composites with 1 wt% and 3 wt% of cotton-based carbon were compared to the composites with the commercial multi-walled carbon nanotubes (MWCNTs). Cotton-based carbon composites with 3 wt% loading exhibited about 90% greater ultimate tensile strength, 150% greater tensile toughness and a moderate increase in Young’s modulus, compared to MWCNT composites. Tribological tests showed the presence of lower friction as a result of the fibrous morphology and consistent carbon-rich transfer layers. The electrical conductivity testing further indicated that carbon composites made of waste cotton came close to that of the MWCNT-based composites. These results indicate that carbon based on cotton is a low-cost, eco-friendly additive for achiving mechanically tough, electrically active, and tribologically improved polymer composites.
Rice straw is an abundant lignocellulosic residue with potential as a feedstock for carboxymethyl cellulose (CMC) production. This study optimized sodium monochloroacetate (NaMCA) dosage and reaction time for obtaining CMC derived from Ciherang rice straw using response surface methodology with a central composite design (RSM-CCD). The optimal conditions, 4.40 g NaMCA and 3 h, yielded 25.31% CMC with pH 7.58, whiteness of 74.23%, moisture content of 4.12%, purity of 94.09%, viscosity of 6.8 cP, NaCl content of 5.91%, and desirability of 0.58. ANOVA showed that NaMCA dosage and reaction time significantly affected the yield and pH, whereas the other responses were less sensitive. FTIR confirmed characteristic CMC functional groups, and SEM revealed a distinct fibrillar morphology relative to commercial CMC. Although the product did not fully satisfy food-grade requirements for viscosity and NaCl content, the findings support Ciherang rice straw as a sustainable CMC feedstock and establish a predictive framework for further process optimization.
Knitted cotton fabric pretreatment involves the use of various chemicals and auxiliaries to prepare it for dyeing. Samples of knitted single-jersey cotton fabric of 140 GSM were prewashed with Felosan RGN or alkali pretreated by a combined process, and dyed under the same dyeing parameters; both types of samples were then evaluated. For evaluation, CIELab color difference, K/S value, and color (wash, rubbing, light, and perspiration) fastness were tested. Then, the CIELab color difference was assessed for specific shade percentages, for red, blue, black, and trichromatic combination of primary dyes up to 0.5% (light shade), and yellow up to 1.5% (medium shade), and the results were compared to those obtained for pretreated dyed fabrics. In addition, the prewashed dyed samples were characterized by evaluating various fastness properties. The unavoidable cost analysis revealed the appreciable outcomes of the work.
Liquid smoke is a condensate formed from the incomplete burning of lignocellulosic materials, which generates chemical compounds such as acetic acid, phenols, carbonyls, and their derivatives. This study aims to utilize mahang wood (Macaranga pruinosa) as an alternative raw material for generating liquid smoke and to examine the properties of the resulting compounds. A traditional pyrolysis technique was utilized for the production process, with pyrolysis times of 30, 45, and 60 minutes. A simple condensation system was used to collect the combustion vapors. The findings suggest that mahang wood can generate liquid smoke with a fairly good yield, noted for its dark brown color and unique scent. Preliminary analysis revealed that the primary components were organic acids, phenols, furans, and their derivatives, as identified through GC–MS (Gas Chromatography–Mass Spectrometry) analysis. The research shows that increasing pyrolysis duration decreases the total phenolic content in the liquid smoke, with the highest value of 18.65 mg GAE/g identified at 30 minutes through UV–Vis spectrophotometric analysis. Based on FTIR spectra, prolonged pyrolysis of mahang wood decreases oxygenated and aliphatic groups, while increasing aromatic structures, reflecting enhanced aromatization and structural stability in the resulting pyrolysis products. Consequently, mahang wood possesses considerable potential as an affordable and eco-friendly raw material for producing liquid smoke, while also increasing the added value of local forest resources that are not fully utilized.
The reuse of agro-waste materials as a source of sustainable dyes is a global demand for the textile and allied industries. This study appraises the dyeing performance of a binary extract from Jashir leaves (Prangos ferulacea) and pomegranate peel (Punica granatum) onto cotton fabric. A central composite design consisting of 31 experiments was developed using Design-Expert software, and the experimental results were analyzed using a two-way ANOVA. Eco-friendly chemical mordants and bio-mordants were applied before, after, and during the dyeing of the cotton. It was found that the binary extract at pH 11, obtained from 8 g of powder after microwave (MW) treatment for up to 4 min at 80 °C for 35 min, with 2 g/100 mL of salt, gave excellent colour strength. The evaluation of fastness properties revealed that using the optimum values of the variables, the binary mixture has the potential to furnish colorfast shades.
This study explores how the average stitch length affects the dimensional, mechanical, and functional properties of pure flax Swiss double piqué fabrics produced on a circular knitting machine. The analysis covers structural features, dimensional changes after washing, strength, stretch, crease resistance, and air permeability. Increasing the average stitch length causes systematic structural changes, notably a decrease in the number of wales, while the number of courses remains relatively stable, resulting in a more open, less dense fabric. Structural loosening reduces the weight and thickness of the knitted fabrics. Dimensional changes are anisotropic, with the largest lengthwise changes occurring after the first wash and consistently greater widthwise changes, emphasizing the importance of initial washing for dimensional stability. Mechanical properties are highly direction-dependent: higher breaking forces and lower breaking elongations are found in the length direction, while widthwise extensibility is greater but with a lower breaking force. Increasing the average stitch length reduces both breaking force and elongation, resulting in a mechanically weaker fabric. Functional performance is also impacted: longer average stitch length with less fabric weight lowers lengthwise crease recovery but enhances air permeability. These findings show that stitch length is a key factor for pure flax Swiss double piqué fabrics, while yarn uniformity and elasticity are crucial for producing high-quality textiles.
