Fourier Transform Infrared Spectroscopy Spectroscopy Research Articles

Spectroscopic Investigation of Tomato Seed Germination Stimulated by Trichoderma spp.

Seed germination is a complex process that can be negatively affected by numerous stresses. Trichoderma spp. are known as effective biocontrol agents as well as plant growth and germination stimulators. However, understanding of the early interactions between seeds and Trichoderma spp. remains limited. In the present paper, Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy were used to reveal the nature of tomato seed germination as stimulated by Trichoderma. A rapid response of tomato seeds to Trichoderma spp. was observed within 48 h on Murashige and Skoog medium (MS) substrate, preceding any physical contact. Raman analysis indicated that both Trichoderma species stimulated phenolic compound synthesis by triggering plant-specific responses in seed radicles. The impact of T. harzianum and T. brevicompactum on two tomato cultivars resulted in alterations to the middle lamella pectin, cellulose, and xyloglucan in the primary cell wall. The Raman spectra indicated increased xylan content in NA with T9 treatment as well as increased hemicelluloses in GZ with T4 treatment. Moreover, T4 treatment resulted in elevated conjugated aldehydes in lignin in GZ, whereas the trend was reversed in NA. Additionally, FTIR analysis revealed significant changes in total protein levels in Trichoderma spp.-treated tomato seed radicles, with simultaneous decreases in pectin and/or xyloglucan. Our results indicate that two complementary spectroscopic methods, FTIR and Raman spectroscopy, can give valuable information on rapid changes in the plant cell wall structure of tomato radicles during germination stimulated by Trichoderma spp.

Influence of temperature and gas atmosphere on the thermal decomposition of (NH4)6Mo7O24.4H2O

This study investigates the effects of gas atmosphere and synthesis temperature on the thermal decomposition of (NH4)6Mo7O24.4H2O. Samples were synthesized in a CVD furnace at temperatures of 450, 550, and 650 °C, using different gases: H2, O2, and Ar, individually. The resulting samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometry (VSM), and optical absorbance. XRD results revealed the formation of MoO3 in all samples produced in an O2 atmosphere. However, in samples synthesized in an inert atmosphere (Ar), a mixture of MoO3 and Mo4O11 phases was detected. The same phase mixture was observed in samples produced at 450 and 550 °C in an H2 atmosphere. However, in samples synthesized in H2 at 650 °C, MoO2 mixed with Mo4O11 was formed. Raman and FTIR spectroscopy confirmed the results obtained by XRD, and these two techniques were also used to compare samples synthesized at 550 °C in different environments. The VSM results indicate a paramagnetic response in the analyzed samples, and there is also an increase in magnetization as the percentage of the Mo4O11 phase increases. Absorbance measurements were also performed and further confirm expected changes in sample composition.

Biological activities of fig latex -loaded cellulose acetate/poly(ethylene oxide) nanofiber for potential therapeutics: Anticancer and antioxidant material

Cancer is a fatal disease, and unfortunately, the anticancer drugs harm normal cells. Plant's extracts are the golden key to solving this issue. In this research, fig latex - from Ficus carica- was encapsulated using cellulose acetate (CA) and poly (ethylene oxide) (PEO) polymers via electrospinning method (Fig@CA/PEO). Fig@CA/PEO nanofiber scaffold was characterized by thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The average fiber diameter was decreased with an increase in latex concentration from 715 nm to 583 nm. FT-IR spectroscopy indicated the presence of fig latex in Fig@CA/PEO nanofibers. Compared to 5-fluorouracil, Fig@CA/PEO nanofiber scaffold considered safe towards normal cells (WI-38). Moreover, the nanofiber scaffold was efficient against colon cancer cells (Caco) and liver cancer cells (HepG2) as it demonstrated IC50 values for cells by 23.97 μg/mL and 23.96 μg/mL, respectively. Besides, the nanofiber scaffold revealed mechanistic variations in apoptotic oncogenes; described by the upregulation of BCL2 and P21, combined by downregulation of p53 and TNF. Moreover, the nanofiber scaffold showed antioxidant activity counting 33.4, 36 and 41 % of DPPH scavenging as the fig latex concentration increased. The results demonstrate that the Fig@CA/PEO nanofiber scaffold is a promising substitute to traditional chemotherapy.

A screening method for plastic-degrading fungi

The growing amount of plastic waste requires new ways of disposal or recycling. Research into the biodegradation of recalcitrant plastic polymers is gathering pace. Despite some progress, these efforts have not yet led to technologically and economically viable applications. In this study, we show that respirometric screening of environmental fungal isolates in combination with scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy can be used to identify new strains with the potential for the degradation of plastic polymers. We screened 146 fungal strains, 71 isolated from car repair shops, an environment rich in long-chain hydrocarbons, and 75 isolated from hypersaline water capable of growing at high concentrations of NaCl. When grown in a minimal medium with no carbon source, some strains produced significantly more CO2 when a pure plastic polymer was added to the medium, some only at high salinity. A selection of these strains was shown by FTIR and Raman spectroscopy to alter the properties of plastic polymers: Cladosporium sp. EXF-13502 on polyamide, Rhodotorula dairenensis EXF-13500 on polypropylene, Rhodotorula sp. EXF-10630 on low-density polyethylene and Wickerhamomyces anomalus EXF-6848 on polyethylene terephthalate. Respirometry in combination with specific spectroscopic methods is an efficient method for screening microorganisms capable of at least partial plastic degradation and can be used to expand the repertoire of potential plastic degraders. This is of particular importance as our results also show that individual strains are only active against certain polymers and under certain conditions. Therefore, efficient biodegradation of plastics is likely to depend on a collection of specialized microorganisms rather than a single universal plastic degrader.

Probing Effect of 6MeV Electron Beam Irradiation on Haemoglobin Protein Using Spectroscopic Techniques.

In this work, we study the effect of 6MeV electron beam irradiation on the physicochemical properties of lyophilized Human Haemoglobin A (HbA). Electron beams generated from Race Track Microtron accelerator with energy 6MeV were used to irradiate HbA at fluences of 5 × 1014 e-/cm2 and 10 × 1014 e-/cm2. Pristine and electron beam irradiated HbA were characterized using UV-visible and Fourier transform infrared spectroscopy (FTIR) spectroscopy. The interfacial tension of the aqueous solutions of HbA are also analysed by pendant drop method. Absorbance intensity, % transmittance and interfacial tension decrease with fluence. The peak position of the Soret band (λsoret = 404nm) remains unaffected by the fluences. FTIR spectroscopy confirms the changes in the secondary structure of the haemoglobin. In the amide band I, the percentage of α-helix reduced from 8% to 1%, and an increase in β-sheet (19% to 29%) and β helix (6.3% to 15%) is observed. Interfacial tension decreases from 46.0mN/m and 44.0mN/m with increase in irradiation dose. These finding provides realistic guideline for biological cells exposure to electron beam radiation doses.

Chemically Synthesized Sb-Doped SnO2 Nanoparticles for Supercapacitor Application

This study explores the potential of antimony tin oxide (ATO) as an electrode material for supercapacitor applications. ATO, known for its exceptional electrical conductivity and stability, was synthesized using the coprecipitation method followed by calcination. The resulting ATO powder underwent thorough characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). XRD analysis confirmed the tetragonal morphology and phase purity of ATO nanoparticles, while SEM revealed a sphere-like structure with an irregular surface. FTIR spectroscopy identified various functional groups, including O–H stretching, C–H symmetric and asymmetric vibrations, and the characteristic–SnO2; vibration mode, providing insights into the surface properties crucial for electrochemical performance. Electrochemical evaluations, conducted through cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy, demonstrated a specific capacitance of 140 F/g for the ATO electrode. This notable specific capacitance highlights the potential of ATO as an advanced electrode material for supercapacitors, showcasing its suitability for applications requiring rapid charge-discharge cycles and high specific power. This research contributes to the understanding of ATO’s structural and functional aspects, emphasizing its promising role in advancing supercapacitor technology. The synthesized ATO nanoparticles, characterized by their unique morphology and enhanced electrochemical performance, pave the way for cleaner and more efficient energy storage solutions.

Impact of aluminum fluoride addition on crystallization, structure and thermal properties of lead borate glasses

The glass composition (70-x)PbO–(30-y)B2O3–(x+y)AlF3, where x and y ranges from 0 to 20 mol%, were prepared using the conventional melt-quenching-annealing technique. The structural and thermal properties of the glasses were comprehensively analyzed using techniques like Differential Thermal Analysis (DTA), Dilatometry, Fourier-Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). XRD confirmed the amorphous, non-crystalline structure of the glasses. The glass network was found to be composed of structural units such as PbO4, BO4, BO3 and AlO6 using FTIR spectroscopy. FTIR analysis revealed significant structural changes, including the transformation of BO4 to BO3 units and the increase in non-bridging bonds, particularly with higher AlF3 content. DTA was instrumental in determining characteristic temperatures, such as the glass transition, melting, and peak crystallization temperatures, along with glass stability parameters (∆T, Hr, Tgr) for all samples. The study found that the addition of AlF3 led to a decrease in these characteristic temperatures when replacing B2O3, but an increase when replacing PbO. Variations in the density and thermal expansion of the lead borate glass were observed upon the addition of AlF3, decreasing when substituting for PbO and increasing when substituting for B2O3. These findings provide insights into the properties of oxyfluoride glasses, paving the way for future optimization in their composition for varied applications.

Direct binding and characterization of laccase onto iron oxide nanoparticles

Iron oxide nanoparticles (IONPs) exhibit unique magnetic properties and possess a high surface-to-volume ratio, making them ideal candidates for the conjugation of substances, including enzymes. Laccase (EC 1.10.3.2), an oxidative enzyme with diverse applications, presents an opportunity for enhancing stability and reusability through innovative immobilization techniques, thus reducing overall process costs. In this study, we employed a direct binding procedure via carbodiimide activation to conjugate laccase onto IONPs synthesized using thermal chemical coprecipitation. Stabilization of the nanoparticles was achieved using thioglycerol and polyvinyl alcohol (PVA) as capping agents. Characterization of the synthesized nanoparticles was conducted using UV-spectroscopy, Fourier transform infrared spectroscopy (FTIR), x-ray diffraction, scanning electron microscopy, and energy dispersive x-ray spectroscopy. FTIR spectroscopy analysis confirmed successful laccase binding to magnetic nanoparticles, with binding efficiencies of 90.65% and 73.02% observed for thioglycerol and PVA capped IONPs, respectively. Furthermore, the conjugated enzyme exhibited remarkable stability, retaining nearly 50% of its initial activity after 20 reuse cycles. This research demonstrates that immobilizing laccase onto IONPs enhances its activity, stability, and reusability, with the potential for significant cost savings and expanded applications in various fields.

Effect of particle size and composition on local magnetic hyperthermia of chitosan-Mg1-xCoxFe2O4 nanohybrid.

In this study, Mg1-xCoxFe2O4 (0≤x ≤ 1 with ∆x = 0.1) or MCFO nanoparticles were synthesized using a chemical co-precipitation method and annealed at 200, 400, 600, and 800°C respectively to investigate the structural properties of the materials by X-ray diffractometer (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR). Controlled annealing increased particle size for each value of x. The aim was to investigate how specific loss power (SLP) and maximum temperature (Tmax) during local magnetic hyperthermia were affected by structural alterations associated with particle size and composition. The lattice parameter, X-ray density, ionic radius, hopping length, bond length, cation-cation distance, and cation-anion distance increase with an increase in Co2+ content. Raman and FTIR spectroscopy reveal changes in cation distribution with Co2+ content and particle size. Magnetic properties measured by the physical property measurement system (PPMS) showed saturation magnetization (Ms), coercivity (Hc), remanent magnetization (Mr/Ms), and anisotropy constant (K1) of the Mg1-xCoxFe2O4 nanoparticles increase with Co2+ content and particle size. When exposed to an rf magnetic field, the nanohybrids experienced an increase in both the SLP (specific loss power) and Tmax (maximum temperature) as the particle size initially increased. However, these values reached their peak at critical particle size and subsequently decreased. This occurs since a modest increase in anisotropy, resulting from the presence of Co2+ and larger particle size, facilitates Néel and Brownian relaxation. However, for high anisotropy values and particle size, the Néel and Brownian relaxations are hindered, leading to the emergence of a critical size. The critical size increases as the Co2+ content decreases, but it decreases as the Co2+ content increases, a consequence of higher anisotropy with the increase in Co2+. Additionally, it is noteworthy that the maximum temperature (Tmax) rises as the concentration of nanohybrids grows, but the specific loss power (SLP) decreases. An increased concentration of chitosan-MCFO nanohybrids inhibits both the Néel and Brownian relaxation processes, reducing specific loss power.

FTIR spectroscopy analysis assessment of reclaimed asphalt at asphalt mixing plants to optimize the recycling

Reclaimed asphalt pavements (RA) usually are fully recyclable in new asphalt mixtures. The properties of the individually aged and possibly modified bitumen in the RA will affect the mix design of the new asphalt mixture. Furthermore, the RA may contain hazardous PAH-contamination resulting from coal tar, which was applied in German road pavements up to the 1980′s. For identifying substances that impair or influence reusability of the RA the Fourier transform infrared spectroscopy (FTIR) method was modified. Within a total measuring time of approx. 20 min, the binder contained in a sample of granulated road construction material can be recovered by means of a rapid extraction and measured by FTIR-ATR. By evaluating the measured absorption spectra, samples which have to be considered as PAH-contaminated (with PAH contents ≥ 25 mg/kg) could be distinguished from non-contaminated reclaimed asphalt. Furthermore, the presence of styrene-butadiene-styrene (SBS) modification as well as viscosity-changing organic additives could be identified.

Harnessing of carboxy containing starch nanoparticles as an adsorbent for Cd (II) ions and methylene blue from waste water effluent: synthesis, metrological characterization and properties

Purpose 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). Design/methodology/approach 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. Findings 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. Originality/value 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.

Comprehensive physicochemical characterization of Algerian coal powders for the engineering of advanced sustainable materials

The object of the research is the intriguing and versatile material known as coal that attracted a lot of attention lately because of its potential use in a variety of fields, including cutting-edge building materials, environmental remediation methods, and creative energy storage solutions. This study presents an extensive characterization of Algerian natural coal powders, employing a multifaceted analytical approach that includes Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Raman Spectroscopy, to reveal their physicochemical properties including morphology, particle size distribution, crystalline structure, and functional groups. The SEM analysis unveiled a heterogeneous morphology with a broad particle size distribution, indicative of the coal's complex structure. The XRD findings, refined using Rietveld analysis, distinguish Carbon (C) and Silicon Dioxide (SiO2) as the primary phases, with crystallite sizes measuring 18.7539 nm for C and 16.6291 nm for SiO2. These phases constitute 98.8 % and 12 % of the composition, respectively, while the presence of quartz underscores the coal’s geological background and its thermal resilience. Regarding the results of the FTIR spectroscopy, absorption peaks corresponding to various functional groups are highlighted, suggesting a rich organic and inorganic composition. Raman spectroscopy corroborates the presence of disordered and graphitic carbon structures, emphasizing the coal's potential for diverse applications. These findings underline the significance of Algerian coal powders for environmental remediation, energy storage, and advanced construction materials, contributing to the advancement of sustainable energy solutions.

In Vitro Antioxidant Activity of Green-Synthesized Zinc Oxide (ZnO) Nanoparticles Utilizing Extracts From Allium sativum.

The primary objective of this study was to develop an environmentally friendly and efficient method for synthesizing zinc oxide (ZnO) nanoparticles (NPs), utilizing extracts from Allium sativum (garlic) plants, characterizing the synthesized ZnO NPs using various analytical techniques, and assessing their antibacterial and antioxidant properties. The synthesis process involved utilizing extracts from garlic plants to create ZnO NPs. The NPs were subjected to comprehensive characterization through UV-visible (UV-vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Antibacterial properties were assessed against different microbial strains. In vitro antioxidant properties were evaluated through 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Bioactive compounds in the synthesized NPs were also identified. Analysis of the UV-visspectrum confirmed the synthesis of ZnO NPs with an approximate size of 280 nm, as indicated by the absorption peak in the surface plasmon resonance band. FTIR spectroscopy revealed the presence of functional groups such as hydroxyl and carboxyl groups. SEM analysis determined the dimensions of the NPs to be around 11 nm. XRD patterns exhibited distinct Bragg reflections, confirming specific crystallographic planes. In vitro antioxidant assays demonstrated a reduction in absorbance at 517 nm and 734 nm, indicating antioxidant activity. Antibacterial testing revealed inhibition zones against Escherichia coli, Staphylococcus aureus, Streptococcus mutans,and Enterococcus faecalis. The study successfully synthesized ZnO NPs using an eco-friendly method with garlic plant extracts. Characterization techniques confirmed the structural and chemical properties of the NPs. The synthesized NPsexhibited antioxidant and antibacterial activities, showcasing their potential for various applications. The identification of bioactive compounds further contributes to the understanding of the biological properties of the synthesized NPs.

Influence of sample preparation methods on FTIR spectra for taxonomic identification of tropical trees in the Atlantic forest

The Atlantic forest is one of the world's major tropical biomes due to its rich biodiversity. Its vast diversity of plant species poses challenges in floristic surveys. Fourier transform infrared spectroscopy (FTIR) enables rapid and residue-free data collection, providing diverse applications in organic sample analysis. FTIR spectra quality depends on the sample preparation methodology. However, no research on FTIR spectroscopy methodology for taxonomy has been conducted with tropical tree species. Hence, this study addresses the sample preparation influence on FTIR spectra for the taxonomic classification of 12 tree species collected in the Serra do Mar State Park (PESM) - Cunha Nucleus – São Paulo State, Brazil. Spectra were obtained from intact fresh (FL), intact dried (DL), and heat-dried ground (GL) leaves. The spectra were evaluated through chemometrics using Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), and Linear Discriminant Analysis (LDA) with validation by LDA-PCA. The results demonstrate that sample preparation directly influences tropical species FTIR spectra categorization capability. The best taxonomic classification result for all techniques, validated by LDA-PCA, was obtained from GL. FTIR spectra evaluation through PCA, HCA, and LDA allow for the observation of phylogenetic relationships among the species. FTIR spectroscopy proves to be a viable technique for taxonomic evaluation of tree species in floristic exploration of tropical biomes which can complement traditional tools used for taxonomic studies.

FT-IR and HPLC analysis of silver fir (Abies alba Mill.) bark compounds from different geographical provenances

Fourier Transform Infrared Spectroscopy (FT-IR) and High-Performance Liquid Chromatography (HPLC) could be applied to study the provenance of wood, specifically the differentiation of wood resources, as well as the identification of chemical compounds that are connected to the changes that occur in wood as a result of drying treatments. To test this hypothesis, the bark of silver fir (Abies alba Mill.) from trees belonging to seven different geographical provenances was studied, using samples dried at three different temperatures (60, 80, and 100 °C). FT-IR spectroscopy revealed different band assignments in the mid-infrared region depending on fir provenances, whereas the vibrational bands of the biomass functional groups tended to shift to lower wavenumbers. Significant differences were identified between the chemical compounds in the bark depending on the provenances. The largest proportion of the total phenolics was represented by the epicatechin gallate, epicatechin, catechin, and procyanidin dimer B1. Exploratory data analysis was performed using principal component analysis (PCA), hierarchical clustering, and Pearson correlations. This allowed a comparative evaluation of the samples and interpret the findings according to the geographical provenances, respectively ecological conditions in the areas of origin, but also the influence of the drying temperatures of the samples on chemical compounds. The precipitation in the areas of origin decreased total phenolics in silver fir bark samples, and total phenolics differed not only due to the geographic provenance, but also due to drying temperature.

Metal-organic framework MIL-101(Cr): An efficient catalyst for the synthesis of dihydro-pyrimidinones

In this work, a metal–organic framework, MIL-101(Cr), was synthesized using hydrothermal method. As synthesized MIL-101(Cr) was characterized using various techniques such as X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDAX), Raman spectroscopy, and Brunauer-Emmett-Telller (BET) surface area analysis. Dihydro-pyrimidinone derivatives were synthesized in the absence of solvent over the MIL-101(Cr) catalyst. These dihydro-pyrimidinone derivatives were characterized by FTIR, 1H and 13C nuclear magnetic resonance spectroscopy. Less hazardous reactants, milder reaction conditions, and relatively simple catalysts to synthesize dihydro-pyrimidinones are the added advantages of our protocol. Optimal yield, swift reaction time, and the retention of a good catalytic activity up to five cycles are the special benefits of our protocol.

Fuel forensics: Recent advancements in profiling of adulterated fuels by ATR-FTIR spectroscopy and chemometric approaches

Gasoline and diesel are the main petroleum products used for road transportation in India. Due to this reason, adulteration can be done by fraudsters using different miscible substances such as kerosene, turpentine, thinner, ethanol etc. In this work, Fourier transform infrared spectroscopy (FTIR) coupled with principal component analysis (PCA) and partial least square regression (PLSR) were used to investigate adulteration in petroleum products and to design an adulterant profiling. ATR-FTIR has an advantage over other traditional methods as it is less time-consuming and needs no extraction procedure. The samples used for the study were prepared by adding different volume of adulterant (0–20%) to standard diesel and gasoline samples. According to the results obtained from this study, ATR-FTIR spectroscopy proved to be the most comprehensible method for the detection of adulteration in diesel and gasoline fuels. Furthermore, the use of FTIR spectroscopy combined with PCA got best segregation of adulterated samples. The predictive model achieved a root mean square error of prediction of 0.477% and 0.592% for diesel and gasoline respectively.

Optimization and characterization of sustainable geopolymer mortars based on palygorskite clay, water glass, and sodium hydroxide

Abstract The synthesis of ambient-cured sustainable geopolymer mortars (GMs) was studied throughout this work. To reduce carbon dioxide emissions, new materials must be used in the production of sustainable concrete and mortars. Many types of binders are used in the synthesis of GM and concrete (GPC), especially clay minerals. These clay minerals are considered sources of alumina and silica in GM and concrete. The geopolymerization process relies on the alkaline solution activating the alumino-silicate to produce geopolymer gel products. The palygorskite (PA) clay mineral, sodium hydroxide (NaOH), and sodium silicates (Na2SiO3) were chosen as a binder (solid material) and alkaline activator solution to synthesize GM at ambient temperature. PA was thermally treated at 550, 650, 700, and 750°C, respectively, to convert into high-reactive PA (HRP) HRP550, HRP650, HRP700, and HRP750, respectively. The characteristics of PA clay, HRP powders, and HRP-based GM were evaluated using compressive strength (CS) testing, X-ray fluorescence analysis, carbon footprint analysis, X-ray diffraction (XRD) diffractograms, Fourier transform infrared spectroscopy (FTIR) spectroscopy, scanning electron microscopy (SEM) images, and energy-dispersive X-ray spectroscopy (EDS) analysis. The maximum CS of 25.1 MPa was acquired for geopolymer synthesis utilizing HRP700-based GM cured at 30°C for 28 days. FTIR spectroscopy demonstrated that HRP-based GM showed the presence of Si–O, Al–O, and O–C–O bonds stretching vibrations in the alumino-silicate network. The results showed that the CO2 emissions had a reduction in the HRP-based GM compared with the reference mix of ordinary Portland cement mortar (OPM). The percentage of reductions was 14.1, 13.7, 13.1, and 12.4 for HRP550, HRP650, HRP700, and HRP750, respectively, compared with the OPM mixture. SEM images/EDS analysis and XRD diffractograms confirmed the presence of sodium alumino-silicate hydrates, magnesium silicate hydrate, and calcium silicate hydrate gels with high quantities particularly in the HRP700-based GM than that in HRP550, HRP650, and HRP750, respectively. The results indicate the suitability of HRP calcined at 700°C (HRP700) in the synthesis of the GM.

Green synthesis of bovine serum albumin–tailored silver nanoparticles from Aspergillus fumigatus: Statistical optimization, characterization, antioxidant, and cytotoxicity evaluation on colon cancer cells

Nanobiotechnology has evolved as a promising technology in developing therapeutically active materials. This study involved the biological synthesis of silver nanoparticles (AgNPs) from extracellular filtrate from the fungal species Aspergillus fumigatus to assess their antioxidant and cytotoxic activity under in‐vitro conditions. This method has become more reliable than physical and chemical approaches, attributed to its use of ecologically clean and non‐toxic methods. These synthesized nanoparticles are then characterized by UV–visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering, scanning electron microscope (SEM), differential scanning calorimetry, and X‐ray diffraction (XRD). Design optimization was done to optimize the selected variables to choose the best‐fit ratios for the experiment. UV spectroscopy showed the absorption peaks for AgNPs and bovine serum albumin (BSA) AgNPs at 300 and 315 nm. FTIR spectroscopy showed amide, carboxyl, and ester groups in BSA AgNPs, indicating their role in stabilizing nanoparticles. The particle size and zeta potential for AgNPs and BSA AgNPs were found to be 124.81 and 152.92 nm; zeta potentials for AgNPS and BSA AgNPs were found to be −13.3 and −15.6 mV. Various antioxidant studies like 2,2‐Diphenyl‐1‐picrylhydrazyl (DPPH), 2,2‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonate) (ABTS), ion chelating assay, lipid peroxide assay, and malondialdehyde were carried out, indicating good antioxidant activity for synthesized nanoparticles. SEM images advocated good spherical images and are well dispersed. The cytotoxic assay performed on HT‐29 colon cancer cells exhibited good inhibition activity for AgNPs and BSA AgNPs, with an IC50 value of 120 and 100 μg/ml. These study results revealed that the synthesized AgNPs, on optimization through Box‐Behnken design, exhibited good antioxidant and cytotoxic activity.

Analysis of Mexican Amber and Natural Resins Using Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy

Amber is a semi-precious gemstone, it is a natural resin formed as a fossil and consists of labdanoid diterpenes. This study involves a compositional analysis of Mexican amber using FTIR Spectroscopy and Raman Spectroscopy, comparing it with resins mixed with sulphur, copal, and rosin, to determine the main spectral features of Mexican amber and identify differences from other fake amber resins. Samples of yellow, red, and green amber were utilised. The equipment used included an ATR FTIR spectrometer and a Raman spectrometer with a 785 nm laser source. In the FTIR analysis, the results reveal that the colour variations in Mexican amber do not reflect structural differences. The ester group is identified in amber through the C=O carbonyl bond at 1727 cm-1, confirmed by a band at 1243 cm-1 and a set of bands between 1200-1060 cm-1 corresponding to C-O-H and O-C-C bonds, respectively. The range between 1000-600 cm-1 is identified as the most crucial for distinguishing authentic amber and determining whether the resin is young or fossilised. In Raman, the main peaks to identify amber are at 1646 cm-1 and 1450 cm-1 with which the ratio of intensities was quantified to determine the maturity of the fossil resin.