Search

Copyright of Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas is the property of Universidad de Santiago de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current study is the first in-depth investigation into the natural radioactivity in soils and assessment of associated radiological risks to the population in Dakshina Kannada district of southern India. The specific activity of natural radionuclides was determined by NaI(Tl) gamma spectroscopy. The trace minerals found in the soil were detected by FTIR spectroscopy and their relative distribution is quantified by calculating the extinction coefficient. The specific activity of 226Ra, 232Th, and 40K range from 9.73 ± 0.7 to 59.97 ± 1.9 Bq kg−1 with a mean of 26.47 ± 1.2 Bq kg−1, 15.88 ± 0.8 to 78.8 5 ± 2.1 Bq kg−1 with a mean of 35.45 ± 1.2 Bq kg−1 and 147.06 ± 3.4 to 535.92 ± 6.7 Bq kg−1 with a mean of 403.11 ± 5.5 Bq kg−1, respectively. The normality of frequency distribution curves of radionuclide concentrations was confirmed by the Kolmogorov–Smirnov test. The estimated hazard indices were found to be within acceptable levels. Higher levels of 226Ra, 232Th and 40K in soils were detected in certain parts of Dakshina Kannada, which was linked to the mineralogy of the region. The specific activity of radionuclides was discovered to be dependent on the minerals kaolinite and calcite. The extinction coefficients of Kaolinite, Calcite, and Quartz in soil ranged from 33.11 to 63.98, 29.63 to 111.24, and 84.47 to 115.83, respectively. [ABSTRACT FROM AUTHOR]

This study provides a comprehensive analysis of the interactions between dimethyl sulfoxide (DMSO) and two small peptides, diglycine and N-acetyl-glycine-methylamide (NAGMA), in aqueous solutions using FTIR spectroscopy and density functional theory (DFT) calculations. ATR-FTIR spectroscopy and DFT results revealed that DMSO does not form direct bonds with the peptides, suggesting that DMSO indirectly influences both peptides by modifying the surrounding water molecules. The analysis of HDO spectra allowed for the isolation of the contribution of water molecules that were simultaneously altered by the peptide and DMSO, and it also explained the changes in the hydration shells of the peptides in the presence of DMSO. In the DMSO–diglycine system, DMSO contributes to the additional strengthening of water hydrogen bonds in the reinforced hydration sphere of diglycine. In contrast, DMSO has a more moderate effect on the water molecules surrounding NAGMA due to the similarity of their hydration shells, leading to a slight weakening of the hydrogen bonds in the NAGMA hydration sphere. DFT/ONIOM calculations confirmed these observations. These findings demonstrated that DMSO influences peptide stability differentially based on their structural characteristics. [ABSTRACT FROM AUTHOR]

The bromoil process, developed in 1907, was a photographic technique highly esteemed by pictorialist photographers for its capacity for image manipulation, which aligns its expressiveness with traditional pictorial techniques. Despite the artistic and technical value of bromoils and their prevalence in renowned collections, there is little research on their composition and structural characteristics. This study uses non-invasive external reflection FTIR spectroscopy to characterise 16 bromoil prints dating from the 1920s to 2010. FTIR spectroscopy allowed the discrimination of key components such as cellulose, gelatine, pigments, and oils, elucidating the structural and compositional complexity of bromoil prints. The study presents new perspectives on the traditionally recognised structure of bromoil prints, based on FTIR spectroscopy results along with evidence from microscopic examination, particularly regarding the role of certain strata in their identification. These results suggest a need to reconsider the understanding and characterisation of bromoil prints in relation to the currently available literature. This research also proposes a measurement model adapted to the studied samples and addresses the advantages and limitations found in the different types of equipment used. It thus proposes a key methodology for the identification and provides a source for the physicochemical studies of photographic processes [ABSTRACT FROM AUTHOR]

Predicting mortality in intensive care units (ICUs) is essential for timely interventions and efficient resource use, especially during pandemics like COVID-19, where high mortality persisted even after the state of emergency ended. Current mortality prediction methods remain limited, especially for critically ill ICU patients, due to their dynamic metabolic changes and heterogeneous pathophysiological processes. This study evaluated how the serum metabolomic fingerprint, acquired through Fourier-Transform Infrared (FTIR) spectroscopy, could support mortality prediction models in COVID-19 ICU patients. A preliminary univariate analysis of serum FTIR spectra revealed significant spectral differences between 21 discharged and 23 deceased patients; however, the most significant spectral bands did not yield high-performing predictive models. By applying a Fast-Correlation-Based Filter (FCBF) for feature selection of the spectra, a set of spectral bands spanning a broader range of molecular functional groups was identified, which enabled Naïve Bayes models with AUCs of 0.79, 0.97, and 0.98 for the first 48 h of ICU admission, seven days prior, and the day of the outcome, respectively, which are, in turn, defined as either death or discharge from the ICU. These findings suggest FTIR spectroscopy as a rapid, economical, and minimally invasive diagnostic tool, but further validation is needed in larger, more diverse cohorts. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies of the influence of gas discharge modification on the physicochemical properties of polyethylene materials by FTIR spectroscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. It was found that treatment of PE materials in radio-frequency gas discharge in air medium leads to oxidation of the surface layer, formation of polar hydroxyl, carbonyl and amino groups, increase in the content of C–O, C=O, C=C, C–N bonds, decrease in the supramolecular ordering of the polymer structure. [ABSTRACT FROM AUTHOR]

In this work, we studied the effect of silver nanoparticles on the IR absorption mechanism in Ag/Ag2O composites. Ag/Ag2O composites were prepared by exposing silver films prepared by thermal evaporation to oxygen plasma afterglow. The infrared spectra of these samples were analysed. The results obtained showed that, the individual silver nanoparticles affect the vibrations of chemical bonds in Ag/Ag2O composites, and this is inferred from the gradual decrease in intensity when moving towards lower wavenumbers. In addition, it was found that the effect of individual silver nanoparticles is greatest in the frequency range of Ag–O bond vibrations and becomes weaker in the case of bonds with higher vibration energies. [ABSTRACT FROM AUTHOR]

Silver-doped Bi1/2Na1/2-xAgxTiO3 (BNAT) ceramics (x = 0.0, 0.025, 0.075, and 0.1) were synthesized using the solid-state reaction (SSR) technique. The structural analysis was performed using the X-ray diffraction (XRD) technique, which revealed the formation of a polycrystalline sample with R3c symmetry. Pristine Bi0.5Na0.5TiO3 (BNT) ceramics exhibited an average crystallite size of ~25.372 nm. Doping a small amount of Ag+ ions in place of Na+ ions resulted in an improved average crystallite size of ~26.365 nm, as calculated by Debye-Scherrer's formula. Raman spectra were employed to investigate the vibrational modes of the materials. The FTIR spectra of Ag+-doped BNT ceramics displayed two strong peaks at ~971 and 537 cm−1, attributed to the presence of metal-oxygen bonds. Room temperature dielectric constant (ε′) and dielectric loss (tan δ) analyses were conducted in the frequency range of 20 Hz to 1 MHz. Complex impedance and modulus spectroscopic analyses indicated the presence of grain boundary effects alongside the bulk contribution and also confirmed the presence of non-Debye relaxations in the materials. [ABSTRACT FROM AUTHOR]

The temperature dependence of the infrared absorption spectra of two Verneuil-grown corundum samples is investigated in the OH stretching range. The spectra display three main bands at 3184, 3232 and 3309 cm− 1, belonging to the so-called “3309 cm− 1 series”, as well as two additional bands at 3163 and 3278 cm− 1 previously reported in some synthetic corundum samples. The anharmonic behavior of the observed bands is analyzed using the pure dephasing model of Persson and Ryberg and depends on the local geometry of the OH defects, which are all associated with Al vacancies. The unexpected increase with temperature in the absorbance of a weak band at 3209 cm− 1 supports a revised interpretation of both the 3209 and 3232 cm− 1 bands. These two bands are interpreted as resulting from the low-temperature equilibrium between two Ti-associated OH defects, enabled by the possibility of hydrogen hopping within the Al vacancy. The temperature-dependent properties of the 3278 cm− 1 band are similar to those of the other Al-vacancy related defects and a comparison with the theoretical properties of selected OH defects suggests that this band corresponds to the association of the H atom with a non-dissociated Al Frenkel pair. Finally, the properties of the band at 3163 cm− 1 are consistent with its previously proposed association with Si for Al substitution in corundum. [ABSTRACT FROM AUTHOR]

The main objective of the present study was to evaluate terroir's role in white and red wine characteristics through human perceptions and electronic assessment. Douro wines, originating from the Douro Demarcated Region (DDR) in the North of Portugal, are renowned for their distinct terroir and historical significance. This study investigates twenty-one Douro wine samples (ten white, eleven red) from Baixo Corgo and Douro Superior through Fourier Transform Infrared (FTIR) spectroscopy, Electronic Nose (E-nose) analysis, and Quantitative Descriptive Analysis (QDA). The research has uncovered unique profiles for each sub-region, influenced by factors such as pH, alcohol content, and acidity. Through principal component analysis, the electronic nose analysis identifies separate clusters in red wines and highlights notable aromatic differences in white wines. The sensory analysis via quantitative descriptive analysis provides detailed wine profiles, emphasizing attributes such as persistence, sweetness, and acidity. Furthermore, emotional responses during wine tasting were assessed using FaceReader analysis, which revealed a range of emotions like happiness, sadness, surprise, fear, and disgust, with different intensities over time. These findings provide valuable insights for consumers, producers, and the enogastronomic industry. [ABSTRACT FROM AUTHOR]

The temperature dependence of the infrared absorption spectra of two Verneuil-grown corundum samples is investigated in the OH stretching range. The spectra display three main bands at 3184, 3232 and 3309 cm− 1, belonging to the so-called “3309 cm− 1 series”, as well as two additional bands at 3163 and 3278 cm− 1 previously reported in some synthetic corundum samples. The anharmonic behavior of the observed bands is analyzed using the pure dephasing model of Persson and Ryberg and depends on the local geometry of the OH defects, which are all associated with Al vacancies. The unexpected increase with temperature in the absorbance of a weak band at 3209 cm− 1 supports a revised interpretation of both the 3209 and 3232 cm− 1 bands. These two bands are interpreted as resulting from the low-temperature equilibrium between two Ti-associated OH defects, enabled by the possibility of hydrogen hopping within the Al vacancy. The temperature-dependent properties of the 3278 cm− 1 band are similar to those of the other Al-vacancy related defects and a comparison with the theoretical properties of selected OH defects suggests that this band corresponds to the association of the H atom with a non-dissociated Al Frenkel pair. Finally, the properties of the band at 3163 cm− 1 are consistent with its previously proposed association with Si for Al substitution in corundum. [ABSTRACT FROM AUTHOR]

The alumino lead borate glasses with small amounts of copper oxide were synthesized by melting and quenching according to the relation 50B2O3-30PbO-(20–x)Al2O3-xCuO with x = 0, 0.10, 0.25, 0.50, 0.75 and 1.00 mol%. The powder XRDs had no sharp peaks which show that the samples are amorphous. Density of the glasses increased as the content of the CuO increased. FTIR spectroscopic studies reveal the presence of BO3, BO4–, PbO4, AlO4, pentaborate [B5O8–], diborate [B4O72–] and dipentaborate B5Ø112– structural units. The UV-visible absorption studies showed that the refractive index, indirect energy gap, oxide ion polarizability and optical basicity had composition dependence which were related to the glass structure. As the CuO concentration increased, the refractive index decreased, indirect energy gap increased, oxide ion polarizability decreased and optical basicity decreased. Optical band gap increased with increasing CuO content as the band gap for bridging oxygens is higher than that for non-bridging oxygens. [ABSTRACT FROM AUTHOR]

The diagnosis of cervical lymph node metastasis from thyroid cancer is an essential stage in the progression of thyroid cancer. The metastasis of cervical lymph nodes directly affects the prognosis and survival rate of patients. Therefore, timely and early diagnosis is crucial for effective treatment and can significantly improve patients' survival rate and quality of life. Traditional diagnostic methods, such as ultrasonography and radionuclide scanning, have limitations, such as complex operations and high missed diagnosis rates. Raman spectroscopy and FTIR spectroscopy can well reflect the molecular information of samples, have characteristics such as sensitivity and specificity, and are simple to operate. They have been widely used in clinical research in recent years. With the development of intelligent medical diagnosis technology, medical data shows a multi-modal trend. Compared with single-modal data, multi-modal data fusion can achieve complementary information, provide more comprehensive and valuable diagnostic information, significantly enhance the richness of data features, and improve the modeling effect of the model, helping to achieve better results. Accurate disease diagnosis. Existing research mostly uses cascade processing, ignoring the important correlations between multi-modal data, and at the same time not making full use of the intra-modal relationships that are also beneficial to prediction. We developed a new multi-modal separation cross-fusion network (MSCNet) based on deep learning technology. This network fully captures the complementary information between and within modalities through the feature separation module and feature cross-fusion module and effectively integrates Raman spectrum and FTIR spectrum data to diagnose thyroid cancer cervical lymph node metastasis accurately. The test results on the serum vibrational spectrum data set of 99 cases of cervical lymph node metastasis showed that the accuracy and AUC of a single Raman spectrum reached 63.63% and 63.78% respectively, and the accuracy and AUC of a single FTIR spectrum reached 95.84% respectively and 96%. The accuracy and AUC of Raman spectroscopy combined with FTIR spectroscopy reached 97.95% and 98% respectively, which is better than existing diagnostic technology. The omics correlation verification obtained correlation pairs of 5 Raman frequency shifts and 84 infrared spectral bands. This study provides new ideas and methods for the early diagnosis of cervical lymph node metastasis of thyroid cancer. [ABSTRACT FROM AUTHOR]

Magnetic nanocomposite was prepared using the wet chemical precipitation approach with varying amounts of cobaltous oxide (CoO). The concentrations of CoO were 0.5, 3.5, 6.5, and 9.5 g per 100 % wollastonite composition. Samples were sintered separately at 1000 and 1200 °C. X-ray diffraction analysis (XRD) of the sintered parent sample revealed the formation of wollastonite CaSiO 3 and larnite Ca 2 SiO 4 , as well as a minor silicon oxide SiO 2 phase. In CoO-doped samples, Co-åkermanite Ca 2 CoSi 2 O 7 and other phases were formed. The XRD and scanning electron microscope SEM confirm the samples' submicron and nanocrystalline microstructure. The Fourier transform infrared spectroscopy (FTIR) and Raman spectra (RS) of investigated samples sintered at 1000 and 1200 °C revealed their bond structure. Both analyses confirmed that incorporating CoO into CaSiO 3 significantly improved its vibrational modes, reflecting structural modifications. By increasing the cobalt oxide content from 3.5 to 9.5 wt%, the samples attain the ideal paramagnetic state, as demonstrated by the magnetic hysteresis (M − H) curve, which is linearly reversible. Formation of the Ca 2 CoSi 2 O 7 significantly alters the magnetic characteristics of the samples, whether through increasing the cobalt oxide concentration up to 9.5 wt% or modifying the sintering temperature. This enables the prepared nonocomposites to be suitable for novel magnetic applications. [ABSTRACT FROM AUTHOR]

ZnTiO 3 nanoparticles (NPS), synthesized using a sol-gel process from zinc acetate dihydrate and titanium tetrabutanolate, were incorporated into aluminum borosilicate glasses to enhance their effectiveness in water purification. Integrating ZnTiO 3 -NPS at the expense of SiO 2 causes significant alterations by converting [BO 3 ] to [BO 4 ], modifying the Si-O bonds with other metal oxides, and creating a denser structure with more bridging oxygens. The structural improvement is indicated by higher ultrasonic velocities and elastic moduli, demonstrating a stronger and more unified glass framework. The study investigates how different concentrations of ZnTiO 3 -NPS affect the glasses' structure and mechanical and optical properties, specifically observing changes in light transmission, such as a blueshift in the absorption edge towards longer wavelengths. This blueshift due to ZnTiO 3 -NPS was assured by the observed decrease in the optical band gap (E g) values and the increase in the mean oscillator position (λ o) values. Furthermore, the real (σ r) and imaginary (σ i) parts of the optical conductivity, nonlinear optical parameters viz. first (χ(1)) and third (χ(3)) orders subsatellites, and nonlinear index of refraction (n 2) have been estimated based on the values of the linear index of refraction (n) and the extinction coefficient (k). The optical modifications impact the refractive index, suggesting various potential technological applications based on the ZnTiO 3 levels. [ABSTRACT FROM AUTHOR]

Eucalyptus essential oil is widely valued for its therapeutic properties and extensive commercial applications, with its chemical composition significantly influenced by species variety, geographical origin, and environmental conditions. This study aims to develop a reliable method for identifying the geographical origin and variety of eucalyptus oil samples through the application of advanced analytical techniques combined with chemometric methods. Essential oils from Eucalyptus globulus and Eucalyptus camaldulensis were analyzed using Gas Chromatography–Flame Ionization Detection (GC–FID) and Fourier Transform Infrared (FTIR) Spectroscopy. Chemometric analyses, including Orthogonal Partial Least Squares-Discriminant Analysis (O2PLS-DA) and Hierarchical Cluster Analysis (HCA), were utilized to classify the oils based on their volatile compound profiles. Notably, O2PLS-DA was applied directly to the raw FTIR data without additional spectral processing, showcasing its robustness in handling unprocessed data. For geographical origin determination, the GC–FID model achieved a Correct Classification Rate (CCR) of 100%, with 100% specificity and 100% sensitivity for both calibration and validation sets. FTIR spectroscopy achieved a CCR of 100%, specificity of 100%, and sensitivity of 100% for the calibration set, while the validation set yielded a CCR of 95.83%, specificity of 99.02%, and sensitivity of 94.44%. In contrast, the analysis based on species variety demonstrated 100% accuracy across all metrics CCR, specificity, and sensitivity—for both calibration and validation using both techniques. These findings underscore the effectiveness of volatile and infrared spectroscopy profiling for quality control and authentication, providing robust tools for ensuring the consistency and reliability of eucalyptus essential oils in various industrial and therapeutic applications. [ABSTRACT FROM AUTHOR]

The changes in the thermal behavior of shelly phosphorite ore from Toolse deposit along the drill-core PH014B (depth 21.1–26.7 m) cut into sub-samples with a length of 0.1 m have been studied. The primary phosphorus-bearing mineral in Estonian phosphorite is fluorcarbonate apatite (francolite) originated from lingual brachiopod shells which during the following millions of years of deposition has partially transformed into fluorhydroxyl apatite. The experiments on a Setaram Labsys Evo 1600 thermoanalyzer coupled with Pfeiffer Omnistar Mass Spectrometer were carried out under non-isothermal conditions at the heating rate of 10 °C min−1 up to 1200 °C in an oxidizing atmosphere containing 79% of Ar and 21% of O2. XRD, FTIR, and XRF methods were used to estimate the mineralogical and chemical composition of the sub-samples. In all studied sub-samples, two minerals prevailed—apatite and quartz. The content of apatite in general decreased moving upwards and the content of quartz increased—both minerals with certain fluctuations depending on the changes in the geological scale of formation of these sediments. Pyrite was also present in all sub-samples, clay minerals (K-mica, illite, chamosite) almost in all, but K-feldspar (sanidine, orthoclase), mostly, in the upper layers. Carbonates (dolomite, calcite) were present in many sub-samples along the drill-core, at that, the content of dolomite was especially high in the deepest sub-samples—between 26.3 and 26.7 m. Organic carbon was concentrated in the upper layers (21.1–23.0 m) of the drill-core, which contained black shale interbeds. Analysis of the results showed a good correlation between the thermal behavior of sub-samples and the changes in their mineralogical and chemical composition along the drill-core. [ABSTRACT FROM AUTHOR]

Accurate identification and rapid genotyping of Candida parapsilosis, a significant opportunistic pathogen in healthcare settings, is crucial for managing outbreaks, timely intervention, and effective infection control measures. This study includes 24 clinical samples and 2 positive environmental surveillance swabs collected during a fluconazole-resistant Candida parapsilosis outbreak at the Tuscany Rehabilitation Clinic (Clinica di Riabilitazione Toscana, CRT), located in the province of Arezzo, Italy. Fourier-transform infrared (FTIR) spectroscopy, genetic sequencing of the ERG11 gene, and short tandem repeat (STR) analysis was applied to track the fluconazole-resistant C. parapsilosis outbreak at the CRT facility. FTIR analysis clustered the isolates into two major groups, correlating with resistance-associated ERG11 mutations (Y132F and R398I), azole resistance levels, and year of isolation. The combined use of FTIR spectroscopy and STR typing provided a comprehensive approach to identify and track fluconazole-resistant C. parapsilosis isolates, which identified specific clusters of genetically similar isolates. By comparison with feasible molecular techniques, we conclude that FTIR spectroscopy applied in real time can inform targeted infection control strategies and aid in the effective management of nosocomial infections. [ABSTRACT FROM AUTHOR]

This work focuses on the changes in the chemical composition of wood caused by impregnation with fire retardants such as guanidine carbonate (GC), urea (U), diammonium phosphate (DAP) and their mixtures. The treated wood was tested using the oxygen index (LOI), Py–GC/MS analysis and FTIR Spectroscopy. The wood was vacuum treated at a pressure of 0.8 MPa for 20 min and then subjected to thermal degradation using the LOI. This way, degraded and nondegraded layers were obtained and ground (0.2 mm). All treatment variants achieved the class of non-flammable materials based on LOI tests; the exception was the 5% urea solution, defined as a flame-retardant material. Using the analytical methods, it was found that cellulose and hemicelluloses undergo the fastest thermal degradation. This study found that the variant protected with a 5% mixture of GC and DAP before and after the degradation process had the best fire-retardant properties regarding cellulose content in the wood. The highest content of anhydrosugars characterised the same variants, the amount of which indicates a slowdown in the degradation process and, consequently, a reduction in the release of levoglucosan during combustion, suggesting potential applications in fire safety. [ABSTRACT FROM AUTHOR]

Gallstone formation is one of the most severe human diseases, with regional differences in gallstone composition worldwide. The formation of gallstones inside the gallbladder is a complex process and is still under debate despite advances in instrumentation. This study was an in‐depth analysis of the chemical, structural, and elemental composition of cholesterol and pigment‐type gallstones using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM–EDS). Thermal gravimetric and differential scanning calorimetry (TG‐DSC) analysis was also carried out on gallstones to predict their thermal behavior. FTIR spectroscopy was employed to distinguish the cholesterol and pigment gallstones. Using SEM, we performed the morphological studies of gallstone and EDS were carried out to analyze elemental distribution within the gallstones. Elemental imaging and mapping of the major and minor elements within the cholesterol and black pigment gallstones were carried out, revealing the stone's heterogeneous nature. The level of heavy and toxic elements was found to be higher in pigment stones than in cholesterol gallstones. The results obtained from TG‐DSC are well correlated and supported by the results from FTIR spectroscopy. [ABSTRACT FROM AUTHOR]

The illegal ivory trade remains a prime threat to elephant populations. Identification of ivory is crucial for combating illicit ivory trading. Studies have demonstrated that FTIR spectroscopy is one of the most suitable techniques for identifying ivory and its products. However, this technique could not have been fully utilized due to the lack of a reference IR spectral library/database. In light of this, the present study aimed to develop the FTIR spectral library for Asian elephant ivory. We collected eight Asian elephant ivory (n = 8) samples from our institute repository and recorded the FTIR spectrum. Further, based on the biochemical composition of ivory, we identified various characteristics, functional groups, and their respective wavenumbers. Furthermore, we used the FTIR spectrum of Asian elephant ivory as a reference to identify the fifteen carvings (n = 15) suspected to be of Asian elephant ivory. The results revealed that samples 1 -13 are visibly identical to the FTIR spectrum of Asian elephant ivory; in contrast, samples 14 and 15 do not match the FTIR spectrum of Asian elephant ivory. Hence, it is confirmed that out of fifteen samples, thirteen are likely to be of Asian elephant ivory origin. To confirm this finding, we employed the PLS-DA analysis. The result showed an R Square value of 0.9 for calibration and 0.75 for validation, and the model exhibited 100% accuracy in classifying the original and fake ivory samples. The results confirmed that FTIR combined with chemometrics analysis was useful for identifying ivory and fake materials. To validate the FTIR results, we extracted the DNA from suspected samples 1–15 and amplified elephant-specific D-loop and Sry (sex-determining region on the Y chromosome) genes. Subsequently, the PCR amplicons were examined on a 2.5% agarose gel and observed for samples 1–13, one band at 137 bp (for D-loop) and another at 97 bp (for Sry). These results indicated that samples 1–13 are of elephant origin, whereas samples 14 and 15 are not of elephant origin. To confirm this finding, the PCR amplicons (D-loop) from nine samples (1–9) were sequenced, and % similarity was analyzed. The results showed 96.6 to 100% similarity to the Mammuthus primigenius, Elephas maximus indicus, and Loxodonta africana. The primers (D-loop and Sry) used in this study are elephant-specific and do not distinguish the elephant species. Overall, DNA-based results supported the results from FTIR analysis and confirmed that the suspected samples 1–13 are of elephant origin and 14 and 15 are not of elephant origin. The current study has demonstrated the identification of ivory substitutes through FTIR spectral library for Asian elephant ivory, which is rapid, cost-effective, and has excellent potential for forensic analysis.Article Highlights: The FTIR spectral library was developed for Asian elephant ivory. The suspected elephant carvings were identified using the FTIR spectral library of Asian elephant ivory. The FTIR results were confirmed through PCR amplification of elephant-specific D-loop and Sry genes. [ABSTRACT FROM AUTHOR]

The influence of annealing temperature on the chemical, structural, and electrophysical properties of porous OSG low-k films containing terminal methyl groups was investigated. The films were deposited via spin coating, followed by drying at 200 °C and annealing at temperatures ranging from 350 °C to 900 °C. In the temperature range of 350–450 °C, thermal degradation of surfactants occurs along with the formation of a silicon-oxygen framework, which is accompanied by an increase in pore radius from 1.2 nm to 1.5 nm. At 600–700 °C, complete destruction of methyl groups occurs, leading to the development of micropores. FTIR spectroscopy reveals that after annealing at 700 °C, the concentration of silanol groups and water reaches its maximum. By 900 °C, open porosity is no longer observed, and the film resembles dense SiO2. JV measurements show that the film annealed at 450 °C exhibits minimal leakage currents, approximately 5 × 10−11 A/cm2 at 700 kV/cm. This can be attributed to the near-complete removal of surfactant residues and non-condensed silanols, along with non-critical thermal degradation of methyl groups. Leakage current models obtained at various annealing temperatures suggest that the predominant charge carrier transfer mechanism is Poole–Frenkel emission. [ABSTRACT FROM AUTHOR]

Glass samples 10RO-30ZnO-xLi2B4O7-(60-x) K2B4O7 (RO=SrO and BaO) with alkali tetra borates varying from 0 to 60 mol% were produced by traditional quenching procedure. Peak free broad X-ray diffraction patterns established the amorphous feature of glass samples. FTIR and Raman spectro-scopic analysis showed the existence of BO3 and BO4 structural groups and other borate units. The BO3 ⇔ BO4 conversion rate was not much affected by variation in one of the alkali-tetrabo-rates. EPR spectra of copper doped glasses confirmed the ground state of Cu2+ ions as 2B1g. Physical and optical properties namely density, molar volume, refractive index, molar refractivity, optical band gap and Urbach energy values were found to be composition dependent. The inflections observed in density, and other optical properties around equal mol.% of alkali oxides in the glass system were attributed to structural modifications and mixed alkali effect. These results exposed the structural variations caused by competitiveness between the two different alkali and alkaline oxides in occupying the geometrical positions of the borate glass network.

Abstract The diagnosis of cervical lymph node metastasis from thyroid cancer is an essential stage in the progression of thyroid cancer. The metastasis of cervical lymph nodes directly affects the prognosis and survival rate of patients. Therefore, timely and early diagnosis is crucial for effective treatment and can significantly improve patients’ survival rate and quality of life. Traditional diagnostic methods, such as ultrasonography and radionuclide scanning, have limitations, such as complex operations and high missed diagnosis rates. Raman spectroscopy and FTIR spectroscopy can well reflect the molecular information of samples, have characteristics such as sensitivity and specificity, and are simple to operate. They have been widely used in clinical research in recent years. With the development of intelligent medical diagnosis technology, medical data shows a multi-modal trend. Compared with single-modal data, multi-modal data fusion can achieve complementary information, provide more comprehensive and valuable diagnostic information, significantly enhance the richness of data features, and improve the modeling effect of the model, helping to achieve better results. Accurate disease diagnosis. Existing research mostly uses cascade processing, ignoring the important correlations between multi-modal data, and at the same time not making full use of the intra-modal relationships that are also beneficial to prediction. We developed a new multi-modal separation cross-fusion network (MSCNet) based on deep learning technology. This network fully captures the complementary information between and within modalities through the feature separation module and feature cross-fusion module and effectively integrates Raman spectrum and FTIR spectrum data to diagnose thyroid cancer cervical lymph node metastasis accurately. The test results on the serum vibrational spectrum data set of 99 cases of cervical lymph node metastasis showed that the accuracy and AUC of a single Raman spectrum reached 63.63% and 63.78% respectively, and the accuracy and AUC of a single FTIR spectrum reached 95.84% respectively and 96%. The accuracy and AUC of Raman spectroscopy combined with FTIR spectroscopy reached 97.95% and 98% respectively, which is better than existing diagnostic technology. The omics correlation verification obtained correlation pairs of 5 Raman frequency shifts and 84 infrared spectral bands. This study provides new ideas and methods for the early diagnosis of cervical lymph node metastasis of thyroid cancer.

In order to lessen carbon emissions, preserve natural resources, and enhance the planet’s sustainability for future generations, environmentally friendly and sustainable composites offer a promising solution that combines technological innovation and environmental responsibility. Therefore, the current study focused on the development of walnut shell (WS) powder as a natural reinforcing additive for polypropylene (PP) composites as sustainable materials for potential automotive applications. Different particle sizes (150, 212, and 300) μm and particle content (10, 20, 30, and 40 wt%) of WS-reinforced PP composites were investigated. This investigation involved two strategies: The first strategy was to determine the best WS size and loading in the PP matrix. The second strategy involved the development of additives by applying dual treatment methods on the WS: alkaline and microwave as chemical and physical treatment at the same time. Under fixation microwave conditions, different NaOH concentrations of 3, 5, and 7% were applied. The extrusion and hot compression processes at fixed operating conditions were used to combine all dosages of WS/PP composites. The mechanical properties of tensile, flexural, and impact for all the composite dosages for the strategies were studied according to ASTM standards D638, D790, and D256, respectively. To confirm the mechanical properties, the influence of treatment techniques on the WS powder and WS/PP composites was also investigated using physicochemical characterization Fourier transform infrared spectroscopy, scanning electron microscope, and X-ray diffraction. Furthermore, the best WS/PP composite was compared with the real automotive part (automobile steering airbag cover [ASAC]) to confirm the mechanical properties of the new WS/PP composites. The results showed that the first strategy obtained a 212 μm, 20 wt% composites that achieved the highest tensile strength, which increased about 1.2 times the tensile strength of the PP matrix. The second strategy showed composite that had treated WS with 7% NaOH (WS7Comp) attained the best mechanical properties throughout other WS/PP composites. In addition, the mechanical properties of the new WS/PP composites were adjusted to the ASAC mechanical properties. Therefore, the improved composites could be a promising alternative material for automotive applications.

Background: Plastic and microplastic (MP) pollution are recognized as a major problem in fresh and marine water bodies. Anthropogenic activities contribute to this kind of pollution. Aruvikkara reservoir, one of the important reservoirs of Kerala, provide drinking water to the capital city, Thiruvananthapuram. Methods: In this study, surface water samples from Aruvikkara reservoir were collected for the assessment of MP pollution during monsoon and post monsoon seasons in 2021. The MP particles were extracted following standard procedure, then examined using stereomicroscope. The particles were analyzed using Fourier-transform infrared (FTIR) spectroscopy for identification and its composition analysis. Results: The MP particles were categorized into different groups namely pellet, fragment, fiber, film and foam. Polyethylene, polypropylene (PP) and polystyrene (PS) were the major classes of MP polymer types identified in the water samples by FTIR spectroscopy. Conclusion: The MP particles may enter into the human body through consumption leading to metabolic changes. Moreover, MPs can enter the food web through trophic transfer, potentially disrupting the normal biological balance of the ecosystem.

Abstract The illegal ivory trade remains a prime threat to elephant populations. Identification of ivory is crucial for combating illicit ivory trading. Studies have demonstrated that FTIR spectroscopy is one of the most suitable techniques for identifying ivory and its products. However, this technique could not have been fully utilized due to the lack of a reference IR spectral library/database. In light of this, the present study aimed to develop the FTIR spectral library for Asian elephant ivory. We collected eight Asian elephant ivory (n = 8) samples from our institute repository and recorded the FTIR spectrum. Further, based on the biochemical composition of ivory, we identified various characteristics, functional groups, and their respective wavenumbers. Furthermore, we used the FTIR spectrum of Asian elephant ivory as a reference to identify the fifteen carvings (n = 15) suspected to be of Asian elephant ivory. The results revealed that samples 1 -13 are visibly identical to the FTIR spectrum of Asian elephant ivory; in contrast, samples 14 and 15 do not match the FTIR spectrum of Asian elephant ivory. Hence, it is confirmed that out of fifteen samples, thirteen are likely to be of Asian elephant ivory origin. To confirm this finding, we employed the PLS-DA analysis. The result showed an R Square value of 0.9 for calibration and 0.75 for validation, and the model exhibited 100% accuracy in classifying the original and fake ivory samples. The results confirmed that FTIR combined with chemometrics analysis was useful for identifying ivory and fake materials. To validate the FTIR results, we extracted the DNA from suspected samples 1–15 and amplified elephant-specific D-loop and Sry (sex-determining region on the Y chromosome) genes. Subsequently, the PCR amplicons were examined on a 2.5% agarose gel and observed for samples 1–13, one band at 137 bp (for D-loop) and another at 97 bp (for Sry). These results indicated that samples 1–13 are of elephant origin, whereas samples 14 and 15 are not of elephant origin. To confirm this finding, the PCR amplicons (D-loop) from nine samples (1–9) were sequenced, and % similarity was analyzed. The results showed 96.6 to 100% similarity to the Mammuthus primigenius, Elephas maximus indicus, and Loxodonta africana. The primers (D-loop and Sry) used in this study are elephant-specific and do not distinguish the elephant species. Overall, DNA-based results supported the results from FTIR analysis and confirmed that the suspected samples 1–13 are of elephant origin and 14 and 15 are not of elephant origin. The current study has demonstrated the identification of ivory substitutes through FTIR spectral library for Asian elephant ivory, which is rapid, cost-effective, and has excellent potential for forensic analysis. Graphical abstract

Vibrational spectroscopic techniques, such as Fourier transform infrared (FTIR) absorption and Raman spectroscopy (RS), offer unique and detailed biochemical fingerprints by detecting specific molecular vibrations within samples. These techniques provide profound insights into the molecular alterations induced by ionising radiation, which are both complex and multifaceted. This paper reviews the application of rapid and label-free vibrational spectroscopic methods for assessing biological radiation responses. These assessments span from early compartmentalised models such as DNA, lipid membranes, and vesicles to comprehensive evaluations in various living biological models, including tissues, cells, and organisms of diverse origins. The review also discusses future perspectives, highlighting how the field is overcoming methodological limitations. RS and FTIR have demonstrated significant potential in detecting radiation-induced biomolecular alternations, which may facilitate the identification of radiation exposure spectral biomarkers/profiles.

Abstract Artificial insemination (AI) success in bovine reproduction is vital for the cattle industry’s economic sustainability and for advancing the understanding of reproductive physiology. Identify high-fertile animals’ fertility is a complex task due to multifactorial traits, including hormonal, age-related, and body condition factors. Early high-fertility identification is crucial for timely interventions and enhancing AI success. In this study, we present the potential use of Fourier-transform infrared (FTIR) spectroscopy on blood serum for early identification of high-fertile Nellore female cows for AI protocols. Blood serum FTIR spectra were obtained from Nellore female cows before AI. FTIR spectra underwent data analysis and the results demonstrated successful discrimination between animals that exhibit pregnant and non-pregnant diagnoses 30 days after AI. FTIR spectra revealed consistent vibrational modes, emphasizing Amide I and II bands. Principal Component Analysis (PCA) effectively segregated groups based on molecular information. Linear SVM with C = 10 and 4 PCs achieved 100% accuracy in the group classification. This innovative approach using FTIR spectroscopy and ML algorithms offers a promising means of high-fertile cow identification, potentially improving AI outcomes in Nellore cattle. The study presents valuable insights into advancements in reproductive management practices for this economically significant breed.

Background Results Conclusion Kenaf seeds are a rich source of protein; however, finding the best extraction method is crucial to obtaining high‐quality protein from these underutilized seeds. This research devised an optimized extraction process for best recovery of kenaf seeds protein using response surface methodology. The key parameters affecting the yield and protein content were optimized, including extraction pH (2–11), seed:water ratio (5:1–50:1), temperature (30–90 °C), and duration (20–360 min). The physicochemical and techno‐functional properties of kenaf seed protein isolates (KSPIs) were examined.A maximum protein yield of 12.05 g/100 g with purity level 91.94 g/100 g was obtained using an optimized extraction with pH 11.0, seed:water ratio 50:1, 360 min duration, and temperature 50 °C. The oil and water retention capacities of KSPI were 1.14 mL g−1 and 1.37 mL g−1 respectively. After 30 min at pH 7, KSPIs demonstrated remarkable emulsion capacity (83.12%) and stability (75.63%), along with high foaming capacity (106%) and stability (18.3%). As per high‐performance liquid chromatography analysis, arginine, glutamic acid, leucine, phenylalanine, and lysine were the most abundant amino acids detected in KPSIs. The KSPIs’ globular protein structure was successfully verified using analytical approaches, including Fourier transform infrared spectroscopy, protein fraction ratios, and differential scanning calorimetry. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed that KPSI has a molecular weight distribution ranging from 10 kDa to 50 kDa.The results of this study support the application of the proposed response‐surface‐methodology‐optimized extraction method for efficient recovery of high‐quality kenaf seed proteins that meet the necessary physicochemical and techno‐functional requirements. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Previously, we found that in the reaction center (RC) of the purple bacterium Cereibacter sphaeroides, formation of heterodimeric primary electron donor (P) caused by the substitution of His-L173 by Leu, was compensated by the second mutation Ile-L177 – His. Significant changes in the spectral properties, pigment composition, and redox potential of P observed in the H(L173)L RC, are restored to the corresponding characteristics of the native RC in the RC H(L173)L/I(L177)H, with the difference that the energy of the long-wavelength QY optical transition of P increases significantly (by ~75 meV). In this work, it was shown using light-induced difference FTIR spectroscopy that the homodimeric structure of P is preserved in the RC with double mutation with partially altered electronic properties: electronic coupling in the radical-cation of the P+ dimer is weakened and localization of the positive charge on one of its halves is increased. Results of the study of the triple mutant RC, H(L173)L/I(L177)H/F(M197)H, are consistent with the assumption that the observed changes in the P+ electronic structure, as well as considerable blue shift of the QY P absorption band in the RC H(L173)L/I(L177)H, are associated with modification of the spatial position and/or geometry of P. Using femtosecond transient absorption spectroscopy, it was shown that the mutant H(L173)L/I(L177)H RC retains a sequence of reactions P* → P+BA− → P+HA− → P+QA− with electron transfer rates and the quantum yield of the final state P+QA− close to those observed in the wild-type RC (P* is the singlet-excited state of P; BA, HA, and QA are molecules of bacteriochlorophyll, bacteriopheophytin, and ubiquinone in the active A-branch of cofactors, respectively). The obtained results, together with the previously published data for the RC with symmetrical double mutation H(M202)L/I(M206)H, demonstrate that by introducing additional point amino acid substitutions, photochemical activity of the isolated RC from C. sphaeroides could be maintained at a high level even in the absence of important structural elements – axial histidine ligands of the primary electron donor P. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is a promising cancer treatment approach. Indocyanine green (ICG) is a water-soluble tricarbocyanine dye with a peak absorption wavelength of around 800 nm and possesses the capacity to produce reactive oxygen species. FTIR spectroscopy is rarely used and offers insights into molecular changes in cancer studies. MCF-7 cells were injected into Nude mouse. Once the tumor had grown to a size of 3–4 mm, mice were randomized into the 12 PDT groups. After each mouse received 5 mg/kg of ICG, they were photo-irradiated with a diode laser emitting light at 809 nm, followed by waiting intervals of 0, 30, 60, and 90 min. Laser irradiation parameters were 150, 250, 500 mW/cm2 and irradiation duration was 1200s. The tumor size was measured every day for four days. The FTIR spectroscopy was used to perform spectral analysis on tumor tissue samples. Four distinct regions (3600–2800 cm-1, 1750–1550 cm-1, 1540–1450 cm-1, and 1700–1100 cm-1) were analyzed, and Hierarchical Cluster study was carried out. A decrease in tumor volume was observed with all PDT applications, except, increases in tumor volume was observed at 150mW 90-minute group. PDT administered after 90 min revealed variations in 150mW and 250mW laser powers in the 3600 cm-1–2800 cm-1 range. The 250mW and 500mW applications resulted in a considerable reduction in fibroadenoma and carcinoma tissues, according to an analysis comparing the A1695 / A1635 ratio. It is proposed that the ideal treatments for further investigation have a power output of 250 mW. [ABSTRACT FROM AUTHOR]

Natural products are a great resource for physiologically active substances. It is widely recognized that a major percentage of current medications are derived from natural compounds or their synthetic analogues. Triterpenoids are widespread in nature and can prevent cancer formation and progression. Despite considerable interest in these triterpenoids, their interactions with lipid bilayers still need to be thoroughly investigated. The aim of this study is to examine the interactions of lupeol, a pentacyclic triterpenoid, with model membranes composed of 1,2‑dipalmitoyl‑sn‑glycerol‑3‑phosphocholine (DPPC) by using non-invasive techniques such as differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The DSC study demonstrated that the incorporation of lupeol into DPPC membranes shifts the Lβ′-to-Pβ′ and Pβ′-to-Lα phase transitions toward lower values, and a loss of main phase transition cooperativity is observed. The FTIR spectra indicated that the increasing concentration (10 mol%) of lupeol causes an increase in the molecular packing and membrane fluidity. In addition, it is found that lupeol's OH group preferentially interacts with the head group region of the DPPC lipid bilayer. These findings provide detailed information on the effect of lupeol on the DPPC head group and the conformation and dynamics of the hydrophobic chains. In conclusion, the effect of lupeol on the structural features of the DPPC membrane, specifically phase transition and lipid packing, has implications for understanding its biological function and its applications in biotechnology and medicine. [ABSTRACT FROM AUTHOR]

Early detection of pre-eclampsia is challenging due to the low sensitivity and specificity of current clinical methods and biomarkers. This study investigates the potential of high-wavenumber FTIR spectroscopy (region between 2800 and 3600 cm−1) as an innovative diagnostic approach capable of providing comprehensive biochemical insights with minimal sample preparation. Blood samples were collected from 33 pregnant women and their corresponding 33 newborns during induction or spontaneous labor. By analyzing the dried blood plasma samples, we identified biomarkers associated with FTIR vibrational modes, including 2853.6 cm−1 (CH2 stretching in lipids), 2873.0 cm−1 (CH3 stretching in lipids and proteins), and 3279.7 cm−1 (O–H stretching related to water and proteins). Machine learning classification revealed 76.3% ± 3.5% sensitivity and 56.1% ± 4.4% specificity in distinguishing between pre-eclamptic and non-pre-eclamptic pregnant women, along with 79.0% ± 3.5% sensitivity and 76.9% ± 6.2% specificity for newborns. The overall accuracy for classifying all pregnant women and newborns was 71.8% ± 2.5%. The results indicate that high-wavenumber FTIR spectroscopy can enhance classification performance when combined with other analytical methods. Our findings suggest that investigating hydrophilic sites may complement plasma analysis in clinical settings. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are considered pollutants of emerging concern. In rivers, MPs (=5 mm) are transported by currents and deposited in lakes, reservoirs, estuaries, and oceans. In Mexico, MPs in freshwater ecosystems have been scarcely studied. This work aimed to determine the presence of MPs in rivers of the Sierra Gorda Biosphere Reserve (SGBR). Samples of surface water and sediment collected from the Escanela, Jalpan, Ayutla, and Santa María rivers were processed. MPs in water were extracted by direct filtration using nitrocellulose filters with a 1.2 µm pore size; MPs in sediments were extracted by density suspension using a ZnCl2 solution (p ≈ 1.5 g/cm3). The surface of MPs was examined using SEM-EDX, and spectra of trace elements deposited on the MPs were obtained; additionally, MP polymers were characterized with FTIR. Fibers were the most abundant MP forms in both matrices. Up to 110.87 items L-1 were detected in water and 175 items kg-1 (dry weight) in sediments. Surface wear of MPs was observed, and trace elements were detected, including Al, Fe, Cr, Si, and Zn, among others. The polymers identified in MP samples were polyethylene terephthalate, polyester, polypropylene, high-density polyethylene, polyamide, and polystyrene. The test results revealed the presence of MPs with trace metals on their surface in the freshwater ecosystems of the SGBR, which may be related to mining operations in the study area, changes in land use, wastewater discharges, atmospheric transport, and dry and wet deposition. These findings demonstrated the ubiquity of these pollutants and their presence even in areas intended for conservation. [ABSTRACT FROM AUTHOR]

Proteins form the fastest-growing therapeutic class. Due to their intrinsic instability, loss of native structure is common. Structure alteration must be carefully evaluated as structural changes may jeopardize the efficiency and safety of the protein-based drugs. Hydrogen deuterium exchange (HDX) has long been used to evaluate protein structure and dynamics. The rate of exchange constitutes a sensitive marker of the conformational state of the protein and of its stability. It is often monitored by mass spectrometry. Fourier transform infrared (FTIR) spectroscopy is another method with very promising capabilities. Combining protein microarrays with FTIR imaging resulted in high throughput HDX FTIR measurements. BaF2 slides bearing the protein microarrays were covered by another slide separated by a spacer, allowing us to flush the cell continuously with a flow of N2 gas saturated with 2H2O. Exchange occurred simultaneously for all proteins and single images covering ca. 96 spots of proteins that could be recorded on-line at selected time points. Each protein spot contained ca. 5 ng protein, and the entire array covered 2.5 × 2.5 mm2. Furthermore, HDX could be monitored in real time, and the experiment was therefore not subject to back-exchange problems. Analysis of HDX curves by inverse Laplace transform and by fitting exponential curves indicated that quantitative comparison of the samples is feasible. The paper also demonstrates how the whole process of analysis can be automatized to yield fast analyses. [ABSTRACT FROM AUTHOR]

A rapid and simple method for identification of oil and fatty products of plant origin by their own fluorescence and diffuse reflection of IR radiation using colorimetry and near-IR spectroscopy is proposed. Analytical signals were recorded using 3D-printed devices with built-in UV and IR LED matrices (390 and 850 nm) and a smartphone with the PhotoMetrix PRO® application installed and FTIR spectroscopy in the near-IR region (10,000–4000 cm–1) with the NIRA attachment used for the analysis of solids. Diffuse reflectance spectra were processed using the TQ Analyst and The Unscrambler X applications. The studied objects were identified and differentiated using chemometric algorithms, i.e., principal component analysis (PCA) and hierarchical cluster analysis (HCA). The mass fraction of fat in the declared products was determined using univariate and multivariate (PLS algorithm) analyses. Adulterated butter was located separately from natural products on the PCA and HCA graphs. They did not intersect with each other on the dendrogram. Samples of butter with different milk fat mass fractions (61.5, 72.5, 82.5, and 99.0%) were used to construct a calibration relationship and determine the milk fat concentration using the PLS method and univariate analysis. The calibration error (RMSEC) were ≤1.31%; the predictive properties (RMSEP), ≤4.45%. The methods under consideration were tested with samples of butter and vegetable oil products from various manufacturers. The RMSEP values for dairy products was ≤4.97%; for margarine, >10% using multivariate analysis. The relative deviation of the results from the mass fractions of fat indicated on the packaging was ≤4.8% when using univariate analysis. This parameter for margarine was in the range 96.3–96.5%. The results correlated with those of FTIR spectroscopy. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to the low-temperature synthesis of cobalt-containing diopside pigments based on granulated blast furnace slag and to study the characteristics of the mineral formation processes, changes in the structure and colour indices. Design/methodology/approach: Synthesis of cobalt-containing diopside pigments based was carried out by the directional formation of the mineralogical composition with the introduction of part of the components using granulated blast-furnace slag. Findings: It has been established that the formation of the diopside phase in pigments containing blast-furnace slag as the main component proceeds at low temperatures (1,100°C–1,150 °C). The colour of diopside pigments is formed because of the isomorphic substitution of Si4+ ions for Al3+ ions and Mg2+ ions for Co2+ ions. It is expedient to add CoO in an amount of 0.9 mol (18 Wt.%) into the composition of diopside pigments based on blast-furnace slag to obtain defect-free violet glazes. Practical implications: The developed diopside pigments enable obtaining of high-quality violet glazes for ceramics. The application of the obtained results can significantly reduce the consumption of traditional raw materials in the composition of silicate ceramic pigments, as well as reduce their firing temperature. Originality/value: Calcium, magnesium and silicon oxides are the main components of blast-furnace slag. In addition, granulated blast furnace slag is mainly represented by the glassy phase, which determines its high activity during the firing process. These factors are prerequisites for using the blast-furnace slag as a valuable substitute for chemically pure or natural raw materials in silicate pigments and reducing their firing temperature. [ABSTRACT FROM AUTHOR]

The infrared spectroscopic properties of selected defects involving one proton and one nearby M3+ (M = Al, Cr, Fe) substitution in orthoenstatite are investigated by first-principles calculations. Based on the theoretical results, the absorption bands experimentally observed on synthetic samples with high crystalline quality and low doping levels can be assigned to specific defect configurations. Most of them correspond to Mg vacancies at M2 sites locally compensated by one proton and one M3+ cation at a nearby M1 site. This confirms that the M3+ + H+ = 2 Mg2+ exchange mechanism is the dominant hydrogen incorporation mechanism at the lowest concentration levels in doped enstatite. At higher concentration levels, more complex incorporation mechanisms could become dominant in Al-bearing samples. [ABSTRACT FROM AUTHOR]

Background: As fire regimes continue to evolve in response to climate change, understanding how fire characteristics have responded to changes in the recent past is vital to inform predictions of future fire events. Aims and methods: Using Fourier Transform Infrared (FTIR) spectroscopy, we assessed how fire intensity has changed in two fire-prone landscapes in south-eastern Australia: (1) the Blue Mountains; and (2) Namadgi National Park during the past 3000 years. Key results: Higher aromatic/aliphatic ratios suggest increased high-intensity fire frequency in sediments at the surface of both cores. Increases in the frequency of extreme drought periods, coupled with the change in vegetation and anthropogenic ignitions following colonisation, could have increased the frequency of high-intensity fires in the past ~200 years. Conclusions: FTIR spectroscopy can be used in sediment deposits to infer that the frequency of high-intensity fire events has increased in the past 200 years compared to the previous ~3000 years. Implications: These results are important for understanding how past fire regimes have responded to climate, people and vegetation shifts in the past ~3000 years and can be used to inform models for future predictions and management strategies. Fourier Transform Infrared (FTIR) spectroscopy was applied to sediment deposits in southeastern Australia. The aromatic/aliphatic ratio was used as a proxy for high-intensity fires. The increased frequency of high-intensity fire events could result from interactions between climate, people, and vegetation. The existing fire record was extended by centuries to millennia. [ABSTRACT FROM AUTHOR]

Disposing of non-biodegradable conventional polymers such as polyethylene, polypropylene, polyvinyl chloride, and acrylonitrile-butadiene-styrene (ABS) is a severe environmental problem across the globe. ABS, a non-biodegradable polymer, is widely used for producing auto components, home appliances, electronic goods, etc., but it is not environment friendly. Therefore, there is a pressing need to develop biodegradable polymers as an alternative to non-biodegradable polymer materials. This paper aims to offer blended bio-based polylactic-acid (PLA) polymer with ABS for engineering applications to minimize the consumption of virgin petroleum-based ABS polymer. The effort is to ascertain the best-suited composition of ABS/PLA blended polymer with excellent thermal and mechanical properties. The five specimens of blended ABS/PLA polymers have been prepared using four compositions (80/20, 60/40, 40/60, and 20/80) using the material extrusion (MEX) 3D printing process and assessed for mechanical and thermal properties. The tensile strength and MFR of the ABS/PLA blend increased by 8.75 and 124.35%, respectively, with ABS/PLA polymers having a 20/80 wt.% composition. The thermal analysis of blends with varying blend compositions using DSC and FTIR have shown partial compatibility between ABS and PLA polymers. Furthermore, scanning electron microscopy (SEM) of tensile fractured specimens has been analyzed to support the evidence. [ABSTRACT FROM AUTHOR]

The diverse applications of azo compounds as reagents to bring about chemical synthesis is one of the fastest-growing areas of research. It is well known that the position of the substituents has an important role in the effect of the medicinal, dye industry, thermal, and optical properties of the compounds. In this work, we limit our studies to synthesizing two new diazo dye vanillin derivatives starting from aniline. Nitro aniline compounds 10 and 12 were prepared starting from aniline, and new nitro diazo vanillin derivatives were obtained 4 and 5. Through coupling reactions with vanillin 15 via diazonium salts, 4- hydroxy-3-methoxy-5-((2,4-dinitrophenyl)diazenyl)benzaldehyde 4 was obtained from 2,4-dinitroaniline 10, while 4-hydroxy-3-methoxy-5-((2,4- 6,trinitrophenyl)diazenyl)benzaldehyde 5 resulted from 2,4,6- trinitroaniline 12. The synthesized compounds were characterized by spectroscopic methods; UV-Vis., FTIR, MS, and 1HNMR and melting point determination. The results of the reactions gave good yields of all products. [ABSTRACT FROM AUTHOR]

Salt stress is one of the environmental stresses that significantly reduces crop productivity and quality worldwide. Methods to overcome salt stress include developing salt-resistant crops by inserting various resistance genes or to diagnosing and responding to the effects of salt stress at an early stage. In this study, we investigate the effects of salinity stress on growth, photosynthetic efficiency, and metabolic changes in Brussels sprouts (Brassica oleracea var. gemmifera). Fresh weight and leaf area decreased significantly with increasing NaCl concentration, indicating that salinity stress has a detrimental effect on plant growth. However, chlorophyll fluorescence parameters did not show significant changes, suggesting that photosynthetic efficiency was not significantly affected over 10 days. Fourier transform infrared (FTIR) spectroscopy revealed notable metabolic adjustments, especially in lipids, plastids, proteins, and carbohydrates, indicating biosynthesis of protective compounds such as anthocyanins and proline in response to salinity stress. Pearson correlation analysis confirmed a strong relationship between NaCl concentration and the observed physiological and metabolic changes. The findings highlight the potential of FTIR spectroscopy as a non-destructive tool for early detection of salinity stress and timely intervention to improve crop resilience and yield. This study highlights the widespread application of FTIR spectroscopy in agricultural research to manage abiotic stresses in crops. [ABSTRACT FROM AUTHOR]