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This study aims to identify the bioactive compounds in the Onion (Allium burdickii [A.B]) bulb using Raman and Fourier transform infrared spectroscopy (FTIR) spectroscopy. It assessed the extraction conditions of bioactive compounds from A.B. while evaluating the best extraction conditions.

The research opted for an experimental qualitative approach. It examined the extraction conditions of A.B., namely, temperature (°C), time (min) and mass-to-liquor ratio (M:R) using ultraviolet-visible spectrophotometry. Identification of bioactive compounds present in the dye was performed using Raman spectroscopy and the validation of the results was done by FTIR spectroscopy.

The study determined the best extraction conditions (time, temperature, M:R) for A.B bulb. The study confirmed the presence of bioactive compounds.

The limitation was quantification of bioactive compounds in A.B bulb.

The findings prove that the A.B. bulb can provide a sustainable source of bioactive compounds (functionalized compounds). The study provides suitable extraction conditions for A.B. and further elaborates on the techniques for identifying bioactive compounds in A.B. bulb extracts.

The study provides A.B. as a source of bioactive compounds and a clean dye for textile coloration.

To the best of the authors’ knowledge, there is no documented study on the qualitative analysis of bioactive compounds in A.B using Raman and FTIR. Therefore, the study fulfils the identified need to ascertain alternative procedures for the analysis of bioactive compounds.

Gourd fibres (GF) are a natural biodegradable fibre material with excellent mechanical properties and high tensile strength. The use of natural fibres in composite materials has gained popularity in recent years due to their various advantages, including renewability, low cost, low density and biodegradability. Gourd fibre is one such natural fibre that has been identified as a potential reinforcement material for composites. However, it has low surface energy and hydrophobic nature, which makes it difficult to bond with matrix materials such as polyester. To overcome this problem, chemically adapted gourd fibre has been proposed as a solution. Chemical treatment is one of the most widely used methods to improve the properties of natural fibres. This research evaluates the feasibility and effectiveness of incorporating chemically adapted gourd fibre into polyester composites for industrial fabrication. The purpose of this study is to examine the application of chemically modified GF in the production of polyester composite engineering materials.

This work aims to evaluate the effectiveness of chemically adapted gourd fibre in improving the adhesion of gourd fibre with polyester resin in composite fabrication by varying the GF from 5 to 20 wt.%. The study involves the preparation of chemically treated gourd fibre through surface modification using sodium hydroxide (NaOH), permanganate (KMnO₄) and acetic acid (CH₃COOH) coupling agents. The mechanical properties of the modified fibre and composites were investigated. It was then characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) to determine the changes in surface morphology and functional groups.

FTIR characterization showed that NaOH treatment caused cellulose depolymerization and caused a significant increase in the hydroxyl and carboxyl groups, showing improved surface functional groups; KMnO₄ treatment oxidized the fibre surface and caused the formation of surface oxide groups; and acetic acid treatment induced changes that primarily affected the ester and hydroxyl groups. SEM study showed that NaOH treatment changed the surface morphology of the gourd fibre, introduced voids and reduced hydrophilic tendencies. The tensile strength of the modified gourd fibres increased progressively as the concentration of the modification chemicals increased compared to the untreated fibres.

This work presents the designed composite with density, mechanical properties and microstructure, showing remarkable improvements in the engineering properties. An 181.5% improvement in tensile strength and a 56.63% increase in flexural strength were got over that of the unreinforced polyester. The findings from this work will contribute to the understanding of the potential of chemically adapted gourd fibre as a reinforcement material for composites and provide insights into the development of sustainable composite materials.

The novelty addressed here is undertaken by using tailor-made and fully characterized starch nanoparticles (SNPs) having a particle size ranging from 80 to 100 nm with a larger surface area, biodegradability and high reactivity as a starting substrate for cadmium ions and basic dye removal from wastewater effluent. This was done via carboxylation of SNPs with citric acid via esterification reaction using the dry preparation technique, in which a simple, energy-safe and sustainable process concerning a small amount of water, energy and toxic chemicals was used. The obtained adsorbent is designated as cross-linked esterified starch nanoparticles (CESNPs).

The batch technique was used to determine the CESNPs adsorption capacity, whereas atomic adsorption spectrometry was used to determine the residual cadmium ions concentration in the filtrate before and after adsorption. Different factors affecting adsorption were examined concerning pH, contact time, adsorbent dose and degree of carboxylation. Besides, to validate the esterification reaction and existence of carboxylic groups in the adsorbent, CESNPs were characterized metrologically via analytical tools for carboxyl content estimation and instrumental tools using Fourier-transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM) morphological analysis.

The overall adsorption potential of CESNPs was found to be 136 mg/g when a 0.1 g adsorbent dose having 190.8 meq/100 g sample carboxyl content at pH 5 for 60 min contact time was used. Besides, increasing the degree of carboxylation of the CESNPs expressed as carboxyl content would lead to the higher adsorption capacity of cadmium ions. FTIR spectroscopy analysis elucidates the esterification reaction with the appearance of a new intense peak C=O ester at 1,700 cm⁻¹, whereas SEM observations reveal some atomic/molecules disorder after esterification.

The innovation addressed here is undertaken by studying the consequence of altering the extent of carboxylation reaction expressed as carboxyl contents on the prepared CESNPs via a simple dry technique with a small amount of water, energy and toxic chemicals that were used as a sustainable bio nano polymer for cadmium ions and basic dye removal from wastewater effluent in comparison with other counterparts published in the literature.

This study aims to evaluate the state of preservation of one of the most famous manuscripts dated back to the 15th century using some analytical techniques to identify the manuscript components, explain its deterioration mechanisms and produce some solutions for conservation processes in future studies.

The analytical techniques used were visual assessment, digital microscope, scanning electron microscope (SEM) with EDX, pH measurement, attenuated total reflection – Fourier transform infrared spectroscopy (ATR/FTIR) and cellulose crystallinity.

Stains, missed parts and scratching were the most common aspects of deterioration. Some insects were observed by digital microscope. The SEM showed that linen fibers and goat skin were used to manufacture paper sheets and leather binding. Energy dispersive X-ray analysis proved that niobium and tantalum were added during the manufacture of paper sheets. Carbon black ink was the main writing material. The other pigments used were cinnabar in red ink, gold color from brass and blue color from lapis lazuli. FTIR analysis proved that some chemical changes were noticed. Low crystallinity of the historical paper was obtained. There was a reduction in the pH value of the historical bookbinding.

The importance of the analytical techniques used to detect the main components, forms and mechanism of deterioration of the studied manuscript. The elements of niobium and tantalum were added to paper sheets, which protected them from deterioration. The insects such as house flies and Sitophilus granarius were found in the manuscripts.

This study aims to investigate the ammonia-sensing performance of polyaniline/polyethylene oxide (PANI/PEO) and polyaniline/polyethylene oxide/zinc oxide (PANI/PEO-ZnO) composite nanofibers at room temperature.

Gas sensor structures were fabricated using microfabrication techniques. First, onto the SiO₂ wafer, gold electrodes were fabricated via thermal evaporation. PANI/PEO nanofibers were produced by the electrospinning method, and the ZnO layer was deposited by using radio frequency (RF) magnetron sputtering on the electrospun nanofibers as a sensing layer. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction were performed to characterize the analysis of nanofibers. After all, gas sensing analysis of PANI/PEO and PANI/PEO/ZnO nanofibers was conducted using an experimental setup at room temperature conditions. Furthermore, the impact of humidity (17%–90% RH) on the sensor resistance was actively investigated.

FTIR analysis confirms the presence of functional groups of PANI, PEO and ZnO in nanofiber structure. SEM micrographs demonstrate beads-free, thinner and smooth nanofibers with ZnO contribution to electrospun PANI/PEO nanofibers. Moreover, according to the gas sensing results, the PANI/PEO nanofibers exhibit 115 s and 457 s response time and recovery time, respectively. However, the PANI/PEO/ZnO nanofibers exhibit 245 s and 153 s response time and recovery time, respectively. PANI/PEO/MOx composite nanofibers ensure stability to the NH₃ gas owing to the high surface/volume ratio and decrease in the humidity dependence of gas sensors, making gas sensors more stable to the environment.

In this study, ZnO was deposited via RF magnetron sputtering techniques on PANI/PEO nanofibers as a different approach instead of in situ polymerization to investigate and enhance the sensor response and recovery time of the PANI/PEO/ZnO and PANI/PEO composite nanofibers to ammonia. These results indicated that ZnO can enhance the sensing properties of conductive polymer-based resistive sensors.

This study aims to investigate the potential use of potato peel extracts as antibacterial finishes for cotton fabrics against Staphylococcus aureus and Escherichia coli. Potato peels are abundant as waste and provide a natural, cheaper and sustainable alternative means of preventing the spread of bacterial infections on cotton fabric.

This research included the characterization of potato peel extracts, application of the extract onto cotton fabric and efficacy testing of the treated cotton fabric against bacteria. Phytochemical screening, agar well diffusion antibacterial test, minimum inhibitory concentration and Fourier transform infrared (FTIR) tests were used to characterize the extract. Antibacterial efficacy of the treated fabric was determined qualitatively using the disc diffusion assay and quantitatively using the bacteria reduction test.

Phytochemical screening confirmed the presence of several secondary metabolites including phenols and flavonoids. Antibacterial tests revealed a positive response in Escherichia coli and Staphylococcus aureus with a zone of inhibition of 6.50 mm and 5.60 mm, respectively. Additional peaks on the FTIR spectroscopy confirmed the presence of potato peel extract on the treated cotton fabric. The treated cotton fabrics showed efficacy against Staphylococcus aureus and Escherichia coli up to 20 washes.

This study introduced the application of potato peel extracts onto cotton fabrics and assessment of the antibacterial properties before and after washing. Results of this study suggest that potato peel extracts can be used as an organic eco-friendly antibacterial finish for cotton fabrics.

This study aims to synthesize two different benzoxazines (Bz) monomers using bio-based and petroleum-based primary amines, respectively, and they have been compared to study their thermal and mechanical performances.

A bio-based bisphenol, Divanillin (DiVa), was formed by reacting two moles of vanillin with one mole of ethylenediamine (EDA) which was then reacted firstly with paraformaldehyde and EDA to form the benzoxazine DiVa-EDA-Bz, and secondly with paraformaldehyde and furfuryl amine (FFA) to form the benzoxazine DiVa-FFA-Bz. The molecular structure and thermal properties of the benzoxazines were characterized by fourier transform infrared spectroscopy and nuclear magnetic resonance (1H,13C) spectroscopies, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The benzoxazines were further coated on mild steel panels to evaluate their mechanical properties and chemical resistance.

The DSC results of DiVa-FFA-Bz showed two exothermic peaks related to crosslinking compared to the one in DiVa-EDA-Bz. The DiVa-FFA-Bz also showed a higher heat of polymerization than DiVa-EDA-Bz. The TGA results showed that DiVa-FFA-Bz exhibited higher thermal stability with a residual char of 54.10% than 43.24% for DiVa-EDA-Bz. The chemical resistance test results showed that DiVa-FFA-Bz showed better chemical resistance and mechanical properties due to its higher crosslinking density.

This study shows the use of bio-based materials, vanillin and FFA, for synthesizing a benzoxazine resin and its application at high temperatures.

This study aims to fabricate the acrylic-based polymeric composite coating with a hydrophobic surface associated with natural oil polyol (NOP) and polydimethylsiloxane with the incorporation of 3 Wt.% SiO₂ nanoparticle (SiO₂np) against the corrosive NaCl media.

The structural properties of the formulated polymeric composite coatings were investigated by using Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, water contact angle (WCA) and cross-hatch (X-Hatch) tests. The WCA measurement was used to study the surface wettability of the formulated polymeric composite coatings. The corrosion protection performance of the nanocomposite coated on the mild steel substrate was studied by immersing the samples in 3.5 Wt.% NaCl solution for 30 days using electrochemical impedance spectroscopy.

The enhanced polymeric composite coating system performed with an excellent increase in the WCA up to 111.1° which is good hydrophobic nature and very high coating resistance in the range of 10¹⁰ Ω attributed to the superiority of SiO₂np.

The incorporation of SiO₂np into the polymeric coating could enhance the surface roughness and hydrophobic properties that could increase corrosion protection. This approach is a novel attempt of using NOP along with the addition of SiO₂np.

Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.

The purpose of this study is to highlight the threats related to the utilization of synthetic fibers. Volatile organic compounds, particulates and acid gases are released during the production of polyester and other synthetic textiles. Polyester is problematic solid waste material as it takes centuries to break down and hence causes microplastic pollution. Biodegradable synthetic solutions for the replacement of polyester are a sustainable business marketing these days. The naNia fiber is the breakthrough product and it is claimed a biodegradable, compostable and toxin-free polymer.

In this research, fabric constructed of naNia fiber was dyed with the extract of naturally occurring Lawsonia inermis (henna) plant leaves. The henna dye was extracted in water and ethanol using different methods, and the better extract was selected by the evaluation of ultraviolet-visible spectroscopy and phytochemical analysis. Henna with ethanol extract showed more desirable results hence it was selected to dye naNia fabric. To improve dyeability, premordanting, simultaneous mordanting and postmordanting were done using chitosan, fresh lemon extract and tannic acid, respectively. The dyed fabric samples were subjected to color strength analysis and multiple colorfastness tests.

The colorfastness test has shown good to excellent results. Scanning electron microscope analysis had also shown the attachment of dye molecules to the filaments. This study revealed that henna dye is appropriate to color naNia fiber even without the aid of a mordant.

For the first time, toxicant-free, biodegradable polyester (naNia) is successfully dyed with sustainable and naturally available dyes and mordants.