Fourier Transform Infrared Spectroscopy Analysis Research Articles

"Theory of Pore Conflation" and "Shubhjyot's equation" in the treatment of Brilliant green dye-contaminated water using Jamun leaves biochar

This study investigates the adsorption of Brilliant Green (BG) dye onto biochar derived from Syzygium cumini (Jamun) leaves (JLB). Biochar was produced via pyrolysis at 800 °C and examined employing various methods, including Scanning electron microscopy (SEM–EDX), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, Raman spectroscopy, Zeta potential and X-ray photoelectron spectroscopy (XPS). The optimum parameters for BG dye adsorption, determined by batch adsorption studies, were a temperature of 80 °C, an initial dye concentration of 500 mg L−1, a contact period of 30 min, and an agitation speed of 400 RPM. The maximum adsorption capacity of JLB for BG was 243.90 mg g−1. It was found that the adsorption process adhered to the Freundlich isotherm model and pseudo-second-order kinetics, revealing heterogeneous adsorption with chemisorption. A novel "Theory of Pore Conflation" was proposed to explain enhanced adsorption at higher temperatures, supported by SEM and FTIR analyses. Additionally, a new equation termed "Shubhjyot's equation" was introduced to account for time dependency in adsorption capacity calculations. The thermodynamic analysis demonstrated that the process is endothermic and spontaneous. Isopropanol was the most effective organic solvent for desorption studies, demonstrating biochar regeneration potential for up to five cycles. Phytotoxicity and cyto-genotoxicity assessments demonstrated the environmental safety of JLB compared to BG dye. The use of JLB production offers a way to repurpose agricultural waste, contributing to circular economy principles. This extensive study demonstrates JLB's promise as an effective, economical, and environmentally safe adsorbent for wastewater treatment that eliminates textile dyes.Graphical

Characterization, Bioactive Profiling and Evaluation of the Pharmacological Activities of Ethanol Extract of Lannea welwitschii (Hiern) Engl.

Introduction: Lannea welwitschii is a medicinal plant used in traditional medicine to treat various infectious diseases due to its plethora of bioactive compounds that possess various pharmacological activities. This study aimed to characterize and determine the phytochemical profile and the bioactive compounds responsible for their pharmacological activities. Methods: Phytochemical screening and Gas-Chromatography Mass Spectrometry (GC-MS) analysis were carried out on the ethanolic extract of L. welwitschii to determine the volatile compounds present. Characterization of the crude extract was carried out using Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and Energy Dispersive X-ray spectroscopy (EDX). The antioxidant potential of the extract was evaluated using methods such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant Potential (FRAP). The antibacterial activities were determined using the macro-broth dilution technique. Results: Secondary metabolites such as saponins, tannins, alkaloids, reducing sugars, and cardiac glycoside were identified. The GC-MS analysis showed the presence of 48 bioactive compounds, out of which 12 had peak area percentages ≥ 1%. Some of the bioactive compounds identified include 2-butoxy-ethanol, Dodecanoic acid, Stigmasterol, Isopropenyl, and n-hexadecanoic acid, which have been reported with different biological activities. FTIR analysis revealed the presence of various functional groups which showed major compounds in the plant extract. The morphological features showed the spherical shape of the plant extract with several aggregates, while the EDX analysis identified elements such as silicon, oxygen, and silver. The extract demonstrated inhibitory potential against some of the bacterial isolates. However, Bacillus pumilus, Klebsiella quasipneumoniae, Klebsiella aerogenes, and Staphylococcus aureus are more susceptible with MIC of 0.313 and 0.625 mg/ml respectively. Conclusion: The presence of secondary metabolites and bioactive compounds revealed by the characterization and phytochemical analysis provided enough evidence for the usage of the plant in the treatment of infectious diseases and thus might be considered a therapeutic agent.

Inhibition of Oral Biofilms and Enhancement of Anticancer Activity on Oral Squamous Carcinoma Cells Using Caffeine-Coated Titanium Oxide Nanoparticles.

The fungus Candida albicans is a prominent cariogenic fungal agent that works in association with Streptococcus mutans to accelerate the formation of oral cancer and tooth decay. This study evaluates caffeine-encapsulated titanium oxide nanoparticles (CF-TiO2 NPs) for their potential to prevent biofilm formation on teeth and enhance oral anticancer treatment by influencing apoptotic gene regulation. The synthesized CF-TiO2 NPs were characterized using ultraviolet, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy analyses, and their antioxidant activity was confirmed through free radical quenching studies. Antimicrobial efficacy was assessed using a zone of inhibition test, revealing strong activity against dental pathogens with a minimal inhibitory concentration of 80 µg/mL. Molecular docking using AutoDock explored interactions between CF and biofilm target sites, supporting their inhibitory potential. In vitro cytotoxicity studies on KB cancer cells showed a dose-dependent increase in cytotoxic effects, with CF-TiO2 NPs promoting apoptotic gene upregulation at concentrations of 20-160 µg/mL. CF-TiO2 NPs demonstrated excellent antioxidant, antibacterial, and anticancer properties, showcasing their promise for oral therapeutic applications. This research highlights a novel approach to managing oral infections and associated complications while improving systemic oral health. Notably, this study is the first to report the biofilm-inhibitory and anticancer potential of CF-TiO2 NPs.

Exploring the intricate studies on low-density polyethylene (LDPE) biodegradation by Bacillus cereus AP-01, isolated from the gut of Styrofoam-fed Tenebrio molitor larvae.

This study aims to investigate the biodegradation potential of a gut bacterial strain, Bacillus cereus AP-01, isolated from Tenebrio molitor larvae fed Styrofoam, focusing on its efficacy in degrading low-density polyethylene (LDPE). The biodegradation process was evaluated through a series of assays, including clear zone assays, biodegradation assays, and planktonic cell growth assessments in mineral salt medium (MSM) over a 28-day incubation period. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed to characterize the alterations in LDPE pellets, followed by molecular characterization. Over three months, sterile soil + LDPE pellets were treated with different concentrations of gut bacterial strain. The degradation capabilities were assessed by measuring pH, total microbial counts, carbon dioxide evolution, weight loss, and conducting phase contrast microscopy and mechanical strength tests. Results demonstrated that MSM containing LDPE as a carbon source with gut bacterial strain produced a clear zone and enhanced planktonic cell growth. FTIR analysis revealed the formation of new functional groups in the LDPE, while SEM images displayed surface erosion and cracking, providing visual evidence of biodegradation. Molecular characterization confirmed the strain as Bacillus cereus AP-01 (NCBI Accession Number: OR288218.1). A 10% inoculum concentration of Bacillus cereus AP-01 exhibited increased soil bacterial counts, carbon dioxide evolution, and pH levels, alongside a notable weight loss of 30.3% in LDPE pellets. Mechanical strength assessments indicated substantial reductions in tensile strength (7.81 ± 0.84 MPa), compression (4.92 ± 0.53 MPa), hardness (51.96 ± 5.62 shore D), flexibility (10.62 ± 1.15 MPa), and impact resistance (14.79 ± 0.94 J). These findings underscore the biodegradation potential of Bacillus cereus AP-01, presenting a promising strategy for addressing the global LDPE pollution crisis.

Investigation of Chloride Salt Erosion on Asphalt Binders and Mixtures: Performance Evaluation and Correlation Analysis.

Asphalt pavement, widely utilized in transportation infrastructure due to its favourable properties, faces significant degradation from chloride salt erosion in coastal areas and winter deicing regions. In this study, two commonly used asphalt binders, 70# base asphalt and SBS (Styrene-Butadiene-Styrene)-modified asphalt, were utilized to study the chloride salt erosion effect on asphalt pavement by immersing materials in laboratory-prepared chloride salt solutions. The conventional properties and adhesion of asphalt were assessed using penetration, softening point, ductility, and pull-off tests, while Fourier transform infrared spectroscopy (FTIR) elucidated the erosion mechanism. The Marshall stability test, freeze-thaw splitting test, and Cantabro test were applied to study the effects of chloride exposure on the strength, water stability, and structural integrity of the asphalt mixture. Finally, the grey correlation analysis was employed to assess the impact of chloride salt erosion on the performance of asphalt binders and mixtures. The findings highlight that chloride salt erosion reduces penetration and ductility in both types of asphalt binders, raises the softening point, and weakens asphalt-aggregate adhesion, confirmed as a primarily physical effect by FTIR analysis. Asphalt mixtures showed decreased strength and water stability, intensifying these impacts at higher chloride concentrations and longer erosion duration. SBS-modified asphalt binders and mixtures exhibited greater resistance to chloride salt erosion, particularly in adhesion, as demonstrated by the Cantabro and pull-out tests. Grey relational analysis revealed that erosion duration is the most influential factor, with TSR and softening point emerging as the most responsive indicators of chloride-induced changes. These findings offer critical insights for practice, providing evidence-based guidance for designing and constructing asphalt pavements in environments with high chloride levels.

Application of Oil Extracted from Cashew Nut Peel (Anacardium occidentale) as an Antioxidant for Biodiesel

The present work aims to extract and test cashew nut peel oil as a natural antioxidant in the oxidative stabilization of biodiesel. Therefore, determinations of the ideal time of Soxhlet and thermal extractions, Fourier transform infrared spectroscopy (FTIR) analyses, and evaluation of the oxidative stability by Rancimat method were carried out. FTIR analyses revealed that the 3rd cycle of extraction was sufficient to extract all the oil, with an average yield of 30.0%. For the thermal extraction of the laboratory technical cashew nut peel oil, the best extraction, based on statistical analysis, was 60 min, yielding 20.0%. The FTIR analysis of the extracted cashew nut peel oil showed characteristic peaks of phenolic groups and organic acids, showing differences in the intensities of the absorption bands. The oxidative stability showed induction period of 8 h 40 min for the hydraulic press extraction, 10 h 35 min for the Soxhlet extraction, and 10 h 65 min for the industrial technical extraction of the cashew nut peel oil. All values were below the 12-h limit established by the National Agency for Petroleum, Natural Gas and Biofuels (ANP). The technical cashew nut peel oil extracted in the laboratory presented an induction period of 11 h 12 min, close to that recommended by ANP, proving to be a promising natural antioxidant. Cardanol presented satisfactory results with 25 h 22 min, double that suggested by ANP. Thus, cashew nut peel oil showed important and promising results as a natural antioxidant for biodiesel.

Preparation and Evaluation of Complexed Ubiquinone (Coenzyme Q10) Antiaging Hyaluronic Acid–Vitamin C Serum for Skin Care

ABSTRACTBackgroundCoenzyme Q10 (CoQ10) is widely recognized for its powerful antioxidant properties, sparking considerable interest in its application within skincare treatments. However, its inherently poor water solubility has posed a major challenge in formulating effective skincare products.MethodsThis research aimed to develop and evaluate a water‐soluble CoQ10 serum by forming a complex with hydroxypropyl β‐cyclodextrin (HPβCD). The study focused on assessing its physicochemical properties, CoQ10 concentration, spread ability, viscosity, pH, physical stability, irritation potential, and diffusion performance. The complexation process was carried out using kneading and trituration techniques, with thorough characterization via validated analytical methods such as solubility tests, Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) analyses.ResultsThe CoQ10–HPβCD complex prepared using the trituration technique at a 2:1 ratio (CoQ10 to HPβCD) demonstrated superior water solubility, reaching 17.5 ± 1.8 mg mL−1, the highest among the tested formulations. Moreover, this formulation achieved the greatest encapsulation efficiency, retaining 71% ± 3.8% of CoQ10. FTIR and DSC analyses confirmed the successful formation of the complex. The formulated serum exhibited shear‐thinning behavior, an optimal pH of 4.3 ± 0.2 closely aligning with the skin's natural acidity for enhanced compatibility—along with excellent spreadability and stability. Diffusion tests revealed a significant enhancement in solubility when CoQ10 was complexed, effectively overcoming its solubility barrier. Irritation tests validated the serum's safety for topical use.ConclusionThis study successfully developed a CoQ10 serum that overcame its solubility limitation, demonstrating favorable properties for skincare application. With its strong physicochemical characteristics and biocompatibility, this formulation shows significant promise for broader incorporation into skincare products.

Characteristics and Applications of Bionanosilica from Betung Bamboo Leaves

Nanoparticles are materials that are currently widely used in research due to their novelty and the growing number of suitable applications. Silica nanoparticles can be produced by synthesizing using several methods such as melting, coprecipitation, sol-gel, and ultrasonication. The aim of this study is to determine the most appropriate synthesis method for the production of SiO₂ nanoparticles to optimize the quality of physical properties of fast-growing wood. The synthesis of SiO2 nanoparticles used in this study utilized three different methods: acid isolation method (F1), sol-gel method (F2), and reflux method (F3). Characterization of SiO2-NPs was performed using particle size analyzer (PSA), X-ray diffraction analysis (XRD), and Fourier transform infrared spectroscopy (FTIR). The results of PSA analysis showed that the acid isolation method produced the smallest SiO2 particle size compared to the sol-gel and reflux methods. The zeta pontential value in each method shows that the particles produced are unstable because the potential zeta value produced is around -10 mV to -30 mV. The results of FTIR and XRD analysis show that the synthesized material is a SiO₂ compound with a cristobalite phase. Application of the material on jabon wood through impregnation showed an improvement in physical properties, including an increase in WPG, density, and BE, especially in the sol-gel method (F2).

Microplastics in Lake sediments in Robert Island, Antarctica

Microplastic (MP) pollution was investigated in the sediment of lakes on Robert Island in the South Shetland Islands located in the northwest of the Antarctic Peninsula. Sediment samples were taken from a glacial lake (L1) and three coastal lakes (L2, L3 and L4) in March and April 2018 as part of the Turkish Antarctic Science Expedition-II (TAE-II). MPs were counted, and physically (shape, colour, size) and chemically characterized by stereomicroscope and Fourier-transform infrared spectroscopy (FT-IR). Fiber and fragments were found in the coastal lakes, while only fibers were found in the glacial lake sediment. The meanMP concentration was 28.3 mp. l-1±37.9 mp. l-1 sediment in the glacial lake and 49.6 mp. l-1±97.1 mp. l-1 sediment in coastal lakes. A total of six different colours of MPs were found with transparent and blue were dominant. The size of MPs varied between 0.08-2.12 mm (mean 0.96±0.55 mm). FT-IR analysis confirmed that MPs were composed of Ethylene Vinyl Acetate (EVA), Polyethylene terephthalate (PET), Polypropylene (PP), Polymethyl Methacrylate (PMMA), Polyethylene (PE), Polyurethane (PU), and Polyacrylonitrile (PAN). Presence of MPs in the lake`s sediment highlights the vulnerability of Antarctica's environment to this unbounded and unpredictable pervasive pollutant and raises concerns about the potential effects of MPs on its unique ecosystems, which are critical to global climate regulation. More comprehensive research on distribution, characteristics, sources and transport of MPs in this remote region is recommended to fully understand the level of risk that MPs represents to ecosystem health.

Chitosan/TiO2/Rosmarinic Acid Bio-Nanocomposite Coatings: Characterization and Preparation

This study aimed to develop and characterize bio-nanocomposite coatings by incorporating titanium nanoparticles (TiO2 NPs) (30–50 nm) (10 mg/L), which have antimicrobial effects, and rosmarinic acid (RA) (0.005 mg/mL), which has strong antioxidant and antimicrobial activities, into the chitosan matrix using the solvent casting method. The prepared bio-nanocomposite coatings were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM-EDX), and atomic force microscopy (AFM). In the XRD analysis, the crystal structure of the bio-nanocomposite coating material was evaluated, but the absence of the expected TiO2 NPs diffraction peak in the coating containing TiO2 NPs was discussed in detail. The TiO2 NPs decreased the crystallinity, compared to the control film, while rosmarinic acid increased the order of the molecular matrix. FT-IR analysis showed the presences of O–H, C=O, and C–O bonds in the coating materials, and the changes in the positions and intensities of the bands observed in the FTIR spectra of the bio-nanocomposite coatings (CHT and CHTRA) proved that TiO2 NPs and RA were successfully integrated into the chitosan matrix. The broadening and flattening of the bands belonging to OH groups (3288–3356 cm−1) indicated that the hydrogen bonds in the chitosan matrix were strengthened during the formation of the bio-nanocomposite structure. The bands representing the C=O stretching vibrations at 1659 cm−1 (amide I) and the N–H bending vibrations at 1558 cm−1 (amide II) indicated protein-based features in the structure of chitosan and confirmed the existence of the bio-nanocomposite structure. The SEM-EDX analysis showed that TiO2 NPs were distributed homogeneously on the chitosan surface, but there was aggregation in places. The AFM images revealed that when TiO2 NPs and RA were added to the chitosan matrix, the surface topography became more homogeneous, and a topographic pattern was formed in the range of 0–20.4 nm. Therefore, it is concluded that these bio-nanocomposite coatings can be used in antimicrobial surfaces and food packaging areas and should be optimized with different antioxidant and nanoparticle combinations in the future.

Environmentally sustainable synthesis of metal nanoparticle clusters and their prospective applications in biomedical and surface enhanced Raman scattering

Abstract In a recent study, gold and silver nanoparticle clusters were successfully synthesized for the first time, to the best of our knowledge, using an environmentally friendly green synthesis method. Both gold and silver nanoparticles exhibit characteristic plasmon resonance peaks at 530 nm and 420 nm respectively with additional peaks at higher wavelengths (620 nm for gold and 580 nm for silver) suggesting the formation of clusters or assemblies of nanoparticles. Scanning Electron Microscopy and Transmission Electron Microscopy analyses reveal that the synthesized gold nanoparticles and silver nanoparticles are predominantly spherical, with average sizes of 10-20 nm for gold nanoparticles and 15-30 nm for silver nanoparticles, along with observable nanoparticle clustering. The Fourier Transform Infrared spectroscopy analysis shows that the functional groups in the Azadirachta indica extract, such as O-H and C-H bonds, participate in the reduction and stabilization of gold and silver nanoparticles. The synthesized gold nanoparticles and silver nanoparticles (showing stronger inhibition) exhibited dose-dependent antibacterial activity against Escherichia coli and antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assays, with silver nanoparticles showing higher scavenging efficiency compared to gold nanoparticles. Further, the surface-enhanced Raman spectroscopy analysis of methyl orange showed significant signal enhancement with silver nanoparticles and gold nanoparticles attributed to inter-plasmon coupling and the creation of hot spots in clustered nanostructures.

Enhanced Rainwater Purification using Cold Plasma-Activated Hyacinth Adsorbent for Pollutant Reduction

This purpose of research for designing a filtration system utilizing hyacinth-based adsorbents to purify rainwater. Hyacinth which an agricultural waste rich in cellulose, possesses natural adsorptive properties. This explores of plasma cold-activated hyacinth adsorbents for rainwater purification, addressing a significant gap in sustainable water treated technologies. Unlike conventional adsorbents, the activation process using cold plasma enhances the adsorbent's surface properties, increasing its efficacy in removing pollutants. A comparative analysis with traditional purification methods demonstrates the superior performance of plasma-activated hyacinth in terms of adsorption capacity and pollutant reduction efficiency. By integrating cold plasma technology with a low-cost, eco-friendly adsorbent, this approach offers a novel solution to improving rainwater quality while promoting environmental sustainability. The study examined variations in carbonization temperatures (600 °C) and evaluated the characteristics of cold plasma-treated and untreated hyacinth adsorbents. Characterization techniques included Scanning Electron Microscopy (SEM) for surface morphology, emission intensity analysis via Optical Electron Spectroscopy to detect plasma-generated species, and Fourier Transform Infrared Spectroscopy (FTIR) to identify functional groups. Results showed that the plasma cold produced Reactive Nitrogen Species (RNS) at wavelengths 324.768–445.289 nm, Reactive Argon Species (R-Ar-S) at 698.223–778.398 nm, and Reactive Oxygen Species (ROS) at 780.341–830.867 nm. SEM analysis revealed that the surface texture of untreated hyacinth adsorbents was smooth, while plasma-treated adsorbents exhibited a rougher surface, enhancing adsorptive efficiency. FTIR analysis identified functional groups such as C=C, C-C, C-N, C=O, and C-O within the range of 700–1750 nm. Rainwater purification efficiency improved significantly with plasma-treated adsorbents, as indicated by reductions in COD (16.22 mg/L), BOD (7.49 mg/L), and TDS (120.22 mg/L), compared to untreated adsorbents, which showed COD of 32.44 mg/L, BOD of 20.26 mg/L, and TDS of 180.46 mg/L. These findings demonstrate the effectiveness of plasma cold-activated hyacinth adsorbents in enhancing rainwater quality.

Sol-gel Synthesized ZnO–SrMn2O4 Nanocomposite and Its Antibacterial Properties

This paper presents the synthesis of new binary oxide nanoparticles (NPs), ZnO–SrMn2O4, with a spinel structure. The sol-gel technique was used to synthesize ZnO–SrMn2O4 spinel-type oxides, which were subsequently investigated for their antibacterial properties. The NPs were characterized by a range of methods, namely Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX). The FTIR analysis revealed the presence of peaks characteristic of SrMn₂O₄ and ZnO/SrMn₂O₄. These peaks confirm the presence of metal-oxygen bonds, namely Zn–O, Mn–O, and Sr–O. SEM was used to analyze the morphology, chemical composition, and size of the nanocrystals. The morphology of the particles is observed to be more irregular in shape, with a wide range of nanoparticle sizes, from 54 to 250 nm. The synthesized nanoparticles, ZnO–SrMn2O4, were used to assess their antibacterial properties against Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, as well as Escherichia coli and demonstrated pronounced antibacterial efficacy. The highest antibacterial activity was recorded against Escherichia Coli, with a diameter range of 16–23 mm, followed by the strain Staphylococcus aureus with a diameter range of 13.5–27.5 mm. The next most active strain was Bacillus subtilis, with a diameter range of 12.5–22 mm, and Bacillus cerus, with a diameter range of 13.5–19 mm. Further use of the obtained ZnO–SrMn2O4 powder is recommended for application in photocatalysis of dye degradation.

Eco-Friendly Fire-Retardant Coating on Cotton Using Layer by Layer Deposition Technique.

Fire hazards are an increasing concern in several high-tech industries of public importance, particularly where textile fabrics are used in abundance. In this study, a novel layer by layer deposition method was utilized to develop a fire-retardant coating on cotton fabric. The method involves a hybrid cationic solution consisting of chitosan and branched polyethyleneimine, while bentonite clay was used as the anionic species. The treated fabric was characterized using SEM, VFT, and attenuated total reflection Fourier transform infrared spectroscopy (FTIR). SEM and EDS profiling confirmed the successful deposition of the (BPEI/CH + BNT) species on the surface of the cotton fabrics. FTIR analysis shows changes in chemical composition between the uncoated and coated samples, as confirmed by modifications in peaks at 3621 cm-1, 1023.3 cm-1, 1631 cm-1, and 614.8 cm-1. Finally, the thermal degradation behavior of pre-coated and post-coated samples was evaluated using thermogravimetric (TGA) analysis within a temperature range of 25 °C~700 °C, where the highest residue of ~19.83% was observed at 700 °C for the D-BPCB-30BL sample, signifying highly improved thermal stability compared to uncoated cotton.

Poly (Lactic Acid) Fibrous Film with Betalains from Pitaya (Stenocereus thurberi) by Electrospinning for Potential Use as Smart Food Packaging

The incorporation of biopolymers and natural colorants in smart packaging has garnered significant attention in the food packaging industry. This study investigates the design and characterization of novel fibrous films incorporating betalain extract (BE) from Stenocereus thurberi in poly (lactic acid) (PLA). An electrospinning technique was developed with varying PLA concentrations (2%–12% w/v) and BE concentrations (8%–12% w/v) to create a colorimetric freshness indicator. BE was characterized by quantifying its phytochemical content and assessing its antioxidant capacity. Morphological and structural analyses included scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), polydispersity index (PI), mechanical properties, and functional characteristics such as ammonia sensitivity and total antioxidant activity. The results indicated that the incorporation of BE significantly influenced the average diameter of the nanofibers, ranging from 313 ± 74 nm to 657 ± 99 nm. SEM micrographs showed that PLA12-BE12 films exhibited smooth surfaces without bead formation. The FTIR analysis confirmed effective BE incorporation, revealing intermolecular interactions between the betalain molecules and the PLA matrix, which contributed to enhanced structural and functional stability. The mechanical properties analysis revealed that moderate BE additions (8%–10% w/v) enhanced the Young’s modulus and tensile strength, while higher BE concentrations (12% w/v) disrupted the polymer network, reducing these properties. Additionally, the strain at break decreased significantly with BE incorporation, reflecting limited molecular chain mobility. Increasing BE concentration notably improved antioxidant activity, with the BE concentration of 12% (w/v), the ABTS•+, DPPH•, and FRAP radical scavenging activities at the highest values of 84.28 ± 1.59%, 29.95 ± 0.34%, and 710.57 ± 28.90 µM ET/g, respectively. Ammonia sensitivity tests demonstrated a significant halochromic transition from reddish-pink to yellow, indicating high sensitivity to low ammonia concentrations. The possible mechanism is alkaline pH induces aldimine bond hydrolysis and generates betalamic acid (yellow) and cyclo-DOPA-5-O-ß-glucoside (colorless) The fibrous films also exhibited reversible color changes and maintained good color stability over 30 days, emphasizing their potential for use in smart packaging applications for real-time freshness monitoring and food quality assessment.

Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali

Strong-alkali activation is a prerequisite needed to ensure the full polymerization activity of alkali slag binder and establish excellent mechanical properties; however, it substantially increases the preparation cost. In this study, the effects of both strong and weak alkaline activators on the activation performance of alkali slag were examined, using a combination of X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy analysis methods. The reaction mechanism was analyzed under different alkaline conditions, and the preparation cost could be significantly reduced without significantly degrading mechanical properties. The results indicate that Ca(OH)2 can stimulate the reactivity of slag, resulting in a 40% decrease in compressive strength (compared to NaOH) but a 25–50% reduction in preparation cost. With increasing Ca(OH)2 dosage, the compressive strength first increases and then decreases. The best excitation effect is achieved at a dosage of 40 g Ca(OH)2 per 450 g GBFS. The formation of aluminosilicate is the main driving force for the observed increase in compressive strength. Excessive dosage of Ca(OH)2 will lead to its deposition in the specimen, thus affecting the development of compressive strength.

Food waste from Parkia biglobosa seed processing as a potential biomass resource for valorization

IntroductionThe valorization of agricultural waste from indigenous sub-Saharan African food processes remains underexplored. By-products from the processing of Parkia biglobosa seeds into condiments are often regarded as pollutants. This research assessed their potential for development in various industrial applications.Materials and methodsThis study employed a standardized protocol adopted in the processing of P. biglobosa seed into condiments, enabling the quantification of food and by-products generated as a percentage. A comparative analysis of the proximate and mineral constituents of the dried food condiment and seed coat (testa) was conducted. Furthermore, the phytochemical constituent of effluents from the two stages of processing was characterized using qualitative and quantitative methods, including Fourier-transform infrared spectroscopy (FTIR) and gas chromatography–mass spectrometry (GC–MS).Results and discussionThe results showed that 66.27% of each 100 g processed P. biglobosa seed used could be considered waste, with 23.19% in seed coat and 29.47% in effluent(s). The seed coat has moisture absorption potential and is fibrous in nature, as confirmed by proximate fiber analysis—15.03 ± 0.13% compared to 9.07 ± 0.10% in the dried condiment. Both the condiments and seed coat contained considerable amounts of sustenance minerals. Effluents from the boiling process exhibited a characteristic starchy effect on textiles. The concentrated effluent from the first stage of boiling had a chocolate-like aroma, sticky texture, and dark-brown color compared to the effluent from the second boiling stage. The FTIR analysis indicated the presence of alcohols, alkenes, aromatic rings, carboxylic acids, and amines in the effluent samples. GCMS characterization reported the presence of specific fatty acids with known health benefits. When premised on the waste-to-wealth initiative, the quantified and characterized by-products of P. biglobosa seed processing, as reported in this study, have potential applications across various industrial processes, including food, cosmetics, pharmaceutical, and agriculture, among others.

Impact of Water Purity and Oxygen Content in Gas Phase on Effectiveness of Surface Cleaning with Microbubbles

Cleaning of surfaces without complex cleaning agents is an important subject, especially in food, pharmaceutical, and biomedical applications. The subject of microbubble and nanobubble cleaning is considered one of the most promising ways to intensify this process. In this work, we check whether and how the purity of water used for microbubble generation, as well as the gas used, affects the effectiveness of cleaning stainless-steel surfaces. Surfaces contaminated with Pluronic L-121 solution were cleaned by water of three purities: ultrapure water (<0.05 μS/cm), water after reversed osmosis (~6.0 μS/cm), and tap water (~0.8 mS/cm). Similarly, three different gases were supplied to the generation setup for microbubble generation: air, oxygen, and nitrogen. Stainless steel plates were immersed in water during microbubble generation and cleaned for a given time. FTIR (Fourier Transform Infrared Spectroscopy) and contact angle analysis were employed for the analysis of surfaces. The results of cleaning were repeatable between plates and showed different cleaning effects depending on both the purity of water (concentration of ions) and gas composition. We have proposed different mechanisms that are dominant with respect to specific combinations of ion concentration and oxygen content in gas, which are directly connected to the microbubble stability and reactivity of gas.

Mechanical behavior, energy absorption, and failure mechanism of 3D‐printed hexagonal honeycomb core under dynamic and quasi‐static loadings

AbstractThe integration of 3D‐printed cellular cores into sandwich composite structures for load‐bearing applications opens up innovative design possibilities while improving structural efficiency. However, ensuring effective energy dissipation under impact conditions without compromising structural integrity remains a challenge. This study investigates the energy absorption and failure mechanisms of 3D‐printed hexagonal honeycomb sandwich composite structures across three different PLA‐based core materials: polylactic acid (PLA), PLA–Carbon, and PLA–Wood, under dynamic and quasi‐static loadings. Material characterization was conducted via Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Failure modes were analyzed using optical microscopy. The results show that PLA–Wood composites demonstrated significant improvement in energy absorption, absorbing 9.22 J of energy at an impact energy of 11 J, compared to 8.49 J for PLA–Carbon while under in‐plane compression, PLA–Wood recorded an energy absorption of 8.74 J, significantly outperforming PLA–Carbon, which reached only 3.05 J. This improvement is attributed to enhanced interfacial adhesion between the wood filler and the PLA matrix, as confirmed by SEM and FTIR analyses. These findings highlight the critical role of filler compatibility in the structural integrity of 3D‐printed sandwich composites, indicating potential applications in the aerospace and automotive industries, where lightweight and durable materials are essential for improving performance.Highlights Dynamic and quasi‐static response of 3D‐printed hexagonal honeycomb cores. Material interactions affect energy absorption through plastic deformation of cores. PLA–Wood outperforms PLA–Carbon in absorbed energy due to filler compatibility. Dynamic loading causes localized core damage with short elastic recovery. Core failure mechanisms with long elastic recovery vary in quasi‐static tests.

Preparation and Performance Analysis of Tung Cake Protein Adhesive.

Tung oil pressing generates a substantial amount of tung cake waste rich in protein, which can be used to develop a novel wood protein adhesive. This study determined the optimal alkali treatment parameters based on NaOH concentration, reaction temperature, and reaction time. Potassium permanganate (KMnO4) and methyl trimethoxy silane (MTMS) were then sequentially added for cross-linking modification to achieve the optimal preparation process for the tung cake protein adhesive. Bonding strength was tested on pressed boards, and various characterization techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TG/TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM), were used. The results indicated the following: (1) Optimal preparation conditions: The best preparation process for the adhesive involved 30% NaOH at 50 °C for 50 min, with the addition of 12% KMnO4 and 6% MTMS, meeting Class II plywood standards. (2) XRD and FTIR analyses revealed that carbohydrates in the tung cake oxidized and reacted with protein amino groups. The active groups in the protein cross-linked with MTMS, forming a spatial network structure, reducing hydrophilic groups, and enhancing water resistance. (3) TG/TGA and DSC showed that the thermal stability of the modified adhesive improved, thermogravimetric loss was reduced, and curing performance was enhanced. (4) SEM verified the adhesive's reaction mechanism, demonstrating that MTMS filled the protein structure unfolded by KMnO4, forming a three-dimensional network and improving bonding strength. This study successfully developed a new, formaldehyde-free, environmentally friendly tung cake protein adhesive with excellent performance.