Reflectance Fourier Transform Infrared Spectroscopy Research Articles

Enhanced CO2 methanation over LaNiO3/CeO2 derivative catalyst with high activity and stability

The conversion of CO2 into synthetic natural gas offers a promising approach for the long-term storage of renewable energy, addressing the challenge of its intermittent supply. This study successfully developed a catalyst comprised of LaNiO3 supported by CeO2, synthesized via a citric acid-aided impregnation method. This catalyst demonstrated efficiency and stability as a precursor for the CO2 methanation reaction. Upon reduction, it transforms into a Ni–La2O3/CeO2 configuration, featuring dispersed Ni nanoparticles. Characterization through hydrogen temperature-programmed reduction (H2-TPR) revealed that this catalyst exhibits enhanced reducibility and smaller particle sizes, which promote hydrogen activation at lower temperatures. X-ray photoelectron spectroscopy (XPS) analysis further clarified that the increased catalytic activity results from electron transfer interactions between Ni, CeO2, and La2O3. Moreover, the catalyst displayed an augmented count of weak to medium basic sites, which, along with improved hydrogen activation, elevated the CO2 conversion rate to 83.8% within the kinetic control region. The collaborative effect of Ni, La2O3, and CeO2 substantially outperformed the conventional Ni/CeO2 catalyst in CO2 methanation efficiency. Additionally, in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) analysis revealed that the methanation process predominantly follows the HCOO* pathway. Notably, the LaNiO3/CeO2 catalyst exceeded the performance of Ni–La/CeO2 in CO2 adsorption, HCOO* intermediate decomposition, and CHO* conversion, significantly enhancing low-temperature methanation activity.

Facile synthesis of Ni-phyllosilicate assisted by polyacrylamide at room temperature for CO2 hydrogenation to methane

To elucidate the effect of solution viscosity on the synthesis of Ni-phyllosilicate, polyacrylamide was incorporated to create a viscous aqueous medium containing of sodium metasilicate, nickel nitrate and NH4F. The enhanced viscosity promotes the dispersion of the initial formed crystal seeds and the growth of Ni-phyllosilicate, culminating in a Ni-rich NiPs-RT-6 of a high Ni content of up to 55.2 wt%. Residual polyacrylamide elimination was accomplished via calcination, concurrently enhancing metal-support interaction. The as-synthesized samples display a nanoflower morphology with nanospheres overlaid with numerous thin nanosheets. The relatively small Ni particles around 5.7 nm were obtained after reduction even at a very high Ni loading, owing to its strong metal-support interaction. NiPs-RT-6 achieves a CO2 conversion of 75.9% at 450 °C, 0.1 MPa, 60 L·g–1·h–1, which closely approximates thermodynamic equilibrium. The turn over frequency for CO2 (TOFCO2) was substantial, calculated at 3.7 × 10–3 s–1, accompanied by activation energy (Ea) of 80.6 kJ·mol–1. In-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) further disclosed that m-HCOO– serves as a crucial intermediate following a formate reaction pathway. With its high Ni content, finely distributed Ni particles, and strong metal-support interaction, NiPs-RT-6 demonstrates promising catalytic activity in CO2 methanation.

Silicon Nitride Surface Enabled Propane Dehydrogenation Catalyzed by Supported Organozirconium.

Mesoporous silicon nitride (Si3N4) is a nontraditional support for the chemisorption of organometallic complexes with the potential for enhancing catalytic activity through features such as the increased Lewis basicity of nitrogen for heterolytic bond activation, increased ligand donor strength, and metal-ligand orbital overlap. Here, tetrabenzyl zirconium (ZrBn4) was chemisorbed on Si3N4, and the resulting supported organometallic species was characterized by Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), Dynamic Nuclear Polarization-enhanced Solid State Nuclear Magnetic Resonance (DNP-SSNMR), and X-ray Absorption Spectroscopy (XAS). Based on the hypothesis that the nitride might enable facile heterolytic C-H bond activation along the Zr-N bond, this material was found to be a highly active (1.53 molpropene molZr-1 h-1 at 450 °C) and selective (99% to propylene) catalyst for propane dehydrogenation. In contrast, the homologous silica supported complex exhibited negligible activity under these conditions.

Photocatalytic CO2 reduction of CuO-Zn1-xCuxO (ZCO)/Ti3C2Tx MXene heterojunctions with enhanced interfacial charge transfer

Photocatalytic CO2 reduction reaction (CO2RR) synthesis of recycled fuel is a promising pathway to assist the mitigating fossil fuel depletion. Finding efficient and inexpensive high performance CO2RR semiconductor photocatalysts is a giant challenge in the field of photocatalytic reduction. This work constructs the novel-designed interfacial Schottky junction of CuO-Zn1-xCuxO (ZCO)/Ti3C2Tx via electrostatic spinning and electrostatic self-assembly techniques. The catalysts exhibit tight contact heterogeneous interface companies with enhanced CO2 chemisorption capability and proved by various characterizations for efficient carrier separation and migration capacity. The optimized ZCO/Ti3C2Tx nanosheet composites significantly improved their photocatalytic performance. The best samples yielded 5.855 and 2.518 μmol g−1 h−1 of CO and CH4, which are 6 and 1.73 times higher than the conversion of ZCO, respectively, and maintain stability after four cycles without the use of sacrificial agents. In addition, the mechanism and reaction pathways of the photocatalytic process are proposed through In-situ diffuse reflectance Infrared Fourier Transform Spectroscopy (In-situ DRIFTS) and X-ray absorption near edge structure (XANES) analysis. This work provides a new semiconductor/co-catalyst system for the photocatalytic reduction of CO2 and demonstrates that Ti3C2Tx MXene is a hopeful and inexpensive co-catalyst.

How are plastic debris affecting the diet of the whitemouth croaker in the Southeastern Brazilian Bight?

The objective of this study was to analyze the presence of plastic debris in the digestive tract contents of Micropogonias furnieri, the most important demersal fish species from the Southeastern Brazilian Bight. In the laboratory, a total of 150 individuals were measured (230≤TL≤674 mm), weighed (136≤TW≤3221 g), and their gut contents were evaluated. The ingested food items were identified, and the plastic debris observed under the stereomicroscope were isolated and subjected to the physical analysis Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) to identify the chemical composition and to determine the polymers. A total of 190 plastic particles were observed in 51.8% of the stomachs containing food. The recovered plastic debris varied from one to twelve particles per individual (mean ± s.d. of 3.33 ± 2.25). Color varied and the particle size ranged from 0.075 to 19.139 mm. There was no relationship between the number of plastic debris recovered in the stomachs of M. furnieri and the total length, total weight, stomach weight, and percent repletion. The most common polymers were polyamide (28.42%), and polystyrene (27.37%), and the total value of polymer hazard index to M. furnieri diet was 35,544.77, corresponding to an extreme danger, with very toxic with long-lasting effects. Considering the effects of plastic ingestion by marine fish and the potential risks to human health, the contamination of the whitemouth croaker with items that are harmful to its diet reveals a problem of environmental contamination, an alarming concern about plastic pollution in marine systems.

Development of Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy Coupled with Multivariate Classification Chemometric Model for Routine Screening of Paracetamol, Ibuprofen, and Aspirin Adulteration in Herbal Products

Objective: The objective of this study is to develop and validate a routine screening test for the determination of three common antipyretic-analgesic synthetic drugs (paracetamol, ibuprofen, and aspirin) adulteration in herbal products using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) coupled with chemometric method. Method: ATR-FTIR spectra of sixteen testing sets of herbal product samples for pain and fever indications were used for multivariate chemometrics model construction. Linear Discriminant Analysis (LDA) was selected as a method for model construction with IBM SPSS for statistical analysis. Model development employed feature selection, such as the stepwise method for variable selection. The model with a high %correct classification and cross-validation was selected and was then validated with an independent testing data set with an auto-prediction test, confusion matrix, and Receiver Operating Characteristic (ROC) curve. To validate the developed test for routine use, the result from ATR-FTIR method was compared with the standard HPLC and TLC analyses used for adulteration screening. objective: Creating validated screening tools for herbal products adulterated with three common antipyretic-analgesic synthetic drugs (Paracetamol, Ibuprofen, and Aspirin) using ATR-FTIR couple with chemometric method Results: The selected model's overall %correct classification result was 97.7%, with a cross-validation of 93.8% rate in training set samples. External validation with an independent testing dataset gave an overall correct classification of 93.8%, with an area under the curve of ROC at 0.979. Comparative testing revealed that model performance was comparable with the HPLC and TLC methods, which routinely detect the presence of paracetamol, aspirin, and ibuprofen. The results of testing set samples classification were consistent with training set samples. Conclusion: Against the standard chromatographic methods, the multivariate chemometric model based on ATR-FTIR demonstrates comparable detection capability to determine adulteration of paracetamol, ibuprofen, and aspirin in herbal products.

Unveiling the Mechanism of Plasma-Catalyzed Oxidation of Methane to C2+ Oxygenates over Cu/UiO-66-NH2.

Nonthermal plasma (NTP) offers the potential for converting CH4 with CO2 into liquid products under mild conditions, but controlling liquid selectivity and manipulating intermediate species remain significant challenges. Here, we demonstrate the effectiveness of the Cu/UiO-66-NH2 catalyst in promising the conversion of CH4 and CO2 into oxygenates within a dielectric barrier discharge NTP reactor under ambient conditions. The 10% Cu/UiO-66-NH2 catalyst achieved an impressive 53.4% overall liquid selectivity, with C2+ oxygenates accounting for ∼60.8% of the total liquid products. In situ plasma-coupled Fourier-transform infrared spectroscopy (FTIR) suggests that Cu facilitates the cleavage of surface adsorbed COOH species (*COOH), generating *CO and enabling its migration to the surface of Cu particles. This surface-bound *CO then undergoes C-C coupling and hydrogenation, leading to ethanol production. Further analysis using CO diffuse reflection FTIR and 1H nuclear magnetic resonance spectroscopy indicates that in situ generated surface *CO is more effective than gas-phase CO (g) in promoting C-C coupling and C2+ liquid formation. This work provides valuable mechanistic insights into C-C coupling and C2+ liquid production during plasma-catalytic CO2 oxidation of CH4 under ambient conditions. These findings hold broader implications for the rational design of more efficient catalysts for this reaction, paving the way for advancements in sustainable fuel and chemical production.

Microplastics removal efficiency and risk analysis of wastewater treatment plants in Oman

Microplastics (MPs) have recently been documented as an emerging pollutant that poses a critical threat to environment. Wastewater treatment plants (WWTPs) are commonly regarded as significant contributors to the presence of MPs. This study aimed to assess the MPs load of three wastewater treatment facilities in Oman using various treatments, including MBR, SBR, and CAS. Wastewater samples from influent, effluent, and sludge were collected and analyzed to determine the concentration, morphology, size, color, and polymer type of the MPs. A set of sieves with a mesh size range of 1 mm–45 μm was used to for filtration. Oxidation treatment was applied for all samples using Fenton's reagent, followed by density separation by sodium chloride solution. The Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR- FTIR) method was utilized to test 10% from each sampling point to confirm the polymer types of the MPs. The pollution load index (PLI) and hazard index (HI) have been employed to assess the risk associated with the chemical toxicity and concentration of detected particles. The PROMETHEE method was used to rank the risk of sampling sites based on different criteria that posed potential ecological and human health risks. The results indicate that the average concentrations of 0.99 MP/L, 1.38 MP/L, and 0.93 MP/L were detected in the final treated effluent of WWTP A, WWTP B, and WWTP C, respectively. These concentrations correspond to overall removal efficiencies of 82.5%, 77.4%, and 79.2% for WWTP A, WWTP B, and WWTP C, respectively Most MPs found in tertiary effluent were smaller particles (425 μm) and fiber-shaped. The major types of MPs were polypropylene (PP), low-density polyethylene (LDPE), polyurethane (PU), polyethylene terephthalate (PET), and Polyvinyl chloride (PVC). This study showed that treated effluent and sludge release significant MPs into the environment.

Furfural adsorption on V2O5 surface: A combined experimental-theoretical study

The adsorption of furfural on the V2O5 surface was investigated using experimental and theoretical methods. In situ Diffuse Reflectance Infrared Fourier-Transform Spectroscopy results show the presence of physi- and chemi-sorption phenomena, where trans-furfural is mostly chemisorbed at the beginning of the adsorption process. These results are in agreement with theoretical DFT results, as the most thermodynamically favored configurations corresponds to the chemisorbed trans-furfural (T1) and cis-furfural (C1) with binding energies of −1.83 and −2.05 eV.

Exploring untapped bacterial communities and potential polypropylene-degrading enzymes from mangrove sediment through metagenomics analysis.

The versatility of plastic has resulted in huge amounts being consumed annually. Mismanagement of post-consumption plastic material has led to plastic waste pollution. Biodegradation of plastic by microorganisms has emerged as a potential solution to this problem. Therefore, this study aimed to investigate the microbial communities involved in the biodegradation of polypropylene (PP). Mangrove soil was enriched with virgin PP sheets or chemically pretreated PP comparing between 2 and 4 months enrichment to promote the growth of bacteria involved in PP biodegradation. The diversity of the resulting microbial communities was accessed through 16S metagenomic sequencing. The results indicated that Xanthomonadaceae, unclassified Gaiellales, and Nocardioidaceae were promoted during the enrichment. Additionally, shotgun metagenomics was used to investigate enzymes involved in plastic biodegradation. The results revealed the presence of various putative plastic-degrading enzymes in the mangrove soil, including alcohol dehydrogenase, aldehyde dehydrogenase, and alkane hydroxylase. The degradation of PP plastic was determined using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), and Water Contact Angle measurements. The FTIR spectra showed a reduced peak intensity of enriched and pretreated PP compared to the control. SEM images revealed the presence of bacterial biofilms as well as cracks on the PP surface. Corresponding to the FTIR and SEM analysis, the water contact angle measurement indicated a decrease in the hydrophobicity of PP and pretreated PP surface during the enrichment.

Ce-based three-dimensional mesoporous microspheres with Mn homogeneous incorporation for toluene oxidation

Ce-based three-dimensional (3D) mesoporous microspheres incorporating Mn were synthesized. Notably, CeMn-0.4, with a Ce/Mn molar ratio of 6:4, exhibited exceptional activity, stability, and resistance to H2O. This superior performance could be attributed to the formation of a CeMn homogeneous solid solution, enhancing the interaction between Ce and Mn and resulting in relatively higher concentrations of Ce3+ and Mn4+. Mn4+ primarily initiated toluene activation owing to its potent oxidative properties, while Ce3+ facilitated oxygen vacancy generation, promoting the activation of gas-phase oxygen and enhancing lattice oxygen mobility. To further elucidate the oxygen reaction mechanisms on the CeMn-0.4 catalyst, experiments and Density Functional Theory (DFT) were combined. It was revealed that gaseous oxygen could be converted into surface reactive oxygen (Oads) species on the catalyst surface, preliminarily oxidizing toluene. Additionally, oxygen vacancies facilitated gas-phase oxygen engagement in toluene oxidation by transitioning it into lattice oxygen (Olat), which was crucial for toluene deep oxidation. Furthermore, the abundance of oxygen vacancies in CeMn-0.4 accelerated the migration of lattice oxygen, thereby facilitating the further oxidation of surface-adsorbed intermediates, as combined by Diffuse Reflectance Fourier Transform Infrared Spectroscopy (DRIFTS).

Wood consolidation through an epoxy‐acrylic gamma‐crosslinked three‐dimensional system

AbstractEmerging technologies based on polymeric materials are progressively developed in order to preserve and consolidate cultural heritage artifacts. In this study, we aimed to obtain a hybrid polymer reliant on two types of thermosets that undergo irreversible crosslinking via ionizing radiation‐induced polymerization, the polymer's structure and characteristics being tailored using specific dose rates, doses, linear energy transfer and monomers ratio, in order to achieve the established performance requirements. Here, we demonstrate a covalently bonded 3D hybrid diepoxy‐triacrylic polymer that is chemically and dimensionally stable, intending to use it as a consolidant of highly degraded wooden artifacts in order to mitigate oxygen inhibition from radical chain reactions, to increase chemical and thermal stability, as well as to obtain a stiffer consolidated artifact, therefore more resistant to deformation. Various types of analytical techniques such as Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy, Mass Spectrometry or Thermal analysis were performed in order to support our strategy and predictions regarding the synergistic effect given by gamma irradiation‐driven crosslinking through simultaneous cationic and radical chain growth polymerization reaction mechanisms. We achieved a homogenous polymeric formulation and wood‐polymer composite materials with high modulus of elasticity, therefore providing up to a twofold increase in Young's modulus in the consolidated wood, a good chemical resistance to various solvents and outstanding thermal resistance up to 381°C. Consequently, the consolidation methodology, as well as mechanical testing, analytical and morphological characterization of the resulted composite will be discussed. Apart from consolidating cultural heritage wooden artifacts, this synthetic route and impregnation methodology provide opportunities for wood‐polymer composites in a wealth of applications as reinforced wood‐based materials.

Development of Zeolite‐Loaded Air‐Brushed Nanofibers for Oral Use and Its Characterization

AbstractZeolites are commercially available and naturally occurring minerals and synthetic materials, they are crystalline aluminosilicates with distinctive chemical and structural properties. Zeolites have a wide range of uses, including catalysis, gas separation, agronomy, animal feed additives, ecology, medicine, and cosmetics. The antibacterial activity of zeolite‐based nanofibers is fabricated and investigated in the current work utilizing a novel airbrushing method. Airbrushing is used to create zeolite‐loaded nanofibers with two groups of 5% and 10% zeolite, respectively. Scanning electron microscopy (SEM), Attenuation of Reflectance Fourier Transform Infrared Spectroscopy (ATR‐FT‐IR), contact angle measurement and an antibacterial test against Streptococcus mutans are used to characterize the fabricated zeolite‐loaded nanofibers. The SEM pictures demonstrate that the innovative strategy used in the study—air brushing—to effectively produce zeolite‐loaded nanofibers is a success. The morphology and diameter in nanometers is verified by SEM images for both groups. The ATR‐FT‐IR peaks confirm the blended compound and its chemical structure. The water contact angle measurement of the nanofibers of both groups show the hydrophobic qualities based on wettability. The findings of the zeolite nanofiber antibacterial test show a zone of inhibition (ZOI) of 19 mm compared to a positive control groups ZOI of 28 mm, indicating superior antibacterial activity against gram‐positive S. mutans. Based on the findings, it can be stated that zeolite nanofiber can be created by airbrushing and has antibacterial properties that can be utilized to stop dental caries, where S. mutans is the primary pathogenic organism.

Synthesis, structural characterization, computational studies, and antifungal activity of isoniazid derivative

In this work, the isoniazid derivative N',N'''-((1E,1′E)-1,4-phenylenebis(methaneylylidene))di(isonicotinohydrazide) (BISHDZHI) was synthesized and characterized by Nuclear Magnetic Resonance (NMR), Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR), Fourier Transform Raman (FT-Raman), and Ultraviolet-Visible (UV–Vis) spectroscopy, and its potential against fungal strains of Candida ssp. was evaluated by in vitro assays. The NMR spectrum confirmed the molecular structure of BISHDZHI. Quantum chemistry computational calculations allowed to obtain the potential energy surface, optimized molecular structure, and to identify all the bands of the Raman, infrared and UV spectra. The data calculated for isoniazid derivative BISHDZHI using the Functional Density Theory (DFT) are in accordance with the experimental values. Our in vitro studies showed that the BISHDZHI compound in association with Fluconazole possesses antifungal action against Candida tropicalis strain, with a reduction of the IC50 24 times to the host. In silico study of ADMET suggested that BISHDZHI has excellent oral bioavailability and metabolic stability, which allows therapeutic action without severe risk to the host. In addition, the molecular docking showed a high interaction potential between the Candida Albicans target. While the molecular dynamics simulations suggested that the BISHDZHI ligand occasioned a minor change in the structure target, indicating more excellent stability than the drug fluconazole.

Synthesis and Characterisation of 4D-Printed NVCL-co-DEGDA Resin Using Stereolithography 3D Printing

The design and manufacturing of objects in various industries have been fundamentally altered by the introduction of D-dimensional (3D) and four-dimensional (4D) printing technologies. Four-dimensional printing, a relatively new technique, has emerged as a result of the ongoing development and advancements in 3D printing. In this study, a stimulus-responsive material, N-Vinylcaprolactam-co-DEGDA (NVCL-co-DEGDA) resin, was synthesised by Stereolithography (SLA) 3D printing technique. The N-Vinylcaprolactam-co-DEGDA resins were initiated by the Diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO) photoinitiator. A range of Di(ethylene glycol) diacrylate (DEGDA) concentrations in the NVCL-co-DEGDA resin was explored, ranging from 5 wt% to 40 wt%. The structural properties of the 3D printed objects were investigated by conducting Attenuated Total Reflectance–Fourier Transform Infrared Spectroscopy (ATR-FTIR). Additionally, the 3D printed samples underwent further characterisation through differential scanning calorimetry (DSC) and swelling analysis. The results revealed an inverse relationship between DEGDA concentration and Tg values, indicating that higher concentrations of DEGDA resulted in lower Tg values. Additionally, the pulsatile swelling studies demonstrated that increasing DEGDA concentration prolonged the time required to reach the maximum swelling ratio. These findings highlight the influence of DEGDA concentration on both the thermal properties and swelling behaviour of 3D printed samples.

Boosting photocatalytic NO oxidation mediated by high redox charge carriers from visible light-driven C3N4/UiO-67 S-scheme heterojunction photocatalyst

The construction of CN/UiO-67 (CNU) S-scheme heterojunction composites through in situ formation of UiO-67 on carbon nitride (C3N4) helps to address the limitations of carbon nitride (CN) in photocatalytic NO elimination. The optimized CNU3 demonstrates superior photocatalytic efficiency, which is attributed to electronic channels constructed by Zr-N bonds and S-scheme electron transport mechanism, effectively promoting the efficient separation of photogenerated charge carriers with high redox potentials. Density Functional Theory (DFT) calculations reveal redistributed electronic orbitals in CNU3, with progressive and continuous energy levels near the Fermi level, which bolsters electronic conduction. Comprehensive quenching experiments, Electron Paramagnetic Resonance (EPR), and in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) analyses highlight a synergistic interplay of electrons, holes, and superoxide radicals in CNU3, inhibiting the generation of toxic nitrogen oxide intermediates and culminating in highly efficient photocatalytic NO oxidation. This study not only elucidates the mechanisms underpinning the enhanced performance of CNU3 heterojunctions but also offers new perspectives on the preparation and interfacial charge separation of heterojunction photocatalysts.

A novel preparation of microporous nanosilica derived from aluminum-extracted residue of coal fly ash for highly selective CO2 adsorption

Currently, the poor adsorption performance caused by the unsatisfactory pore size seriously restricts the further development of microporous nanosilica (MS). Herein, an excellent microporous nanosilica was constructed by preparing calcium silicate hydrate (CSH) support from the aluminum-extracted residue of coal fly ash and modifying it with different activating agents (H2SO4, HNO3, HCl, CH3COOH, KOH, NaOH and Na2CO3). The results indicated that CH3COOH at 30 wt% was the optimal modifier, achieving a CO2 uptake of 1.42 mmol/g at 298 K and 1.0 bar. Then the effects of synthesis parameters including mass fraction, liquid–solid ratio, temperature, and time on the adsorption capacity of CO2 were further investigated. The obtained MSCp exhibited a high specific surface area (up to 505.71 m2/g), well-developed microporosity (0.085 cm3/g), and excellent CO2 uptake (2.12 mmol/g at 273 K, 1.41 mmol/g at 298 K). Based on the study of kinetics, isosteric heat of adsorption (Qst), and situ diffuse reflectance infrared Fourier transformation spectroscopy (DRIFTS), the adsorption mechanism of MSCp was determined to be mainly physical adsorption. Besides, the excellent CO2/CH4 selectivity of 20.91 (15/85, v/v) and 30.75 (50/50, v/v), CO2/N2 selectivity of 53.79 (15/85, v/v) and 163.76 (50/50, v/v) were obtained from MSCp at 298 K and 1.0 bar. Finally, the binary gas breakthrough experiments and eight adsorption–desorption cycles confirmed the MSCp was suitable for selective adsorption of CO2 in practical applications.

Quantitative Applications of ATR-FTIR Spectroscopy with Chemometrics for the Estimation of Amikacin in Amikacin Sulphate Injections

Background: Amikacin belongs to the class of aminoglycoside antibiotics used in the treatment of gram-negative bacterial infections. It is resistant to the aminoglycosides modifying enzymes, making it a clinically effective drug in multidrug-resistant infections. Methods: In this study, a simple Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy was used for the quantification of amikacin in amikacin sulphate injection. The infrared spectra were generated in the spectral range of 4000–667 cm-1. The calibration curve was computed through TQ Analyst Pro edition software, and the partial least square regression analysis found the linearity in the range of 10-60% w/w. Results: The best calibration results were obtained in the spectral region from 1040 to 1020 cm-1 with a correlation coefficient (r2) of 1.000. The residual mean standard error (RMSEC) value was 0.00235. The percent relative standard deviation (%RSD) values for intra-day and inter-day precision were less than 8.0. The percent relative error (%RE) values were calculated and found in between the range of 0.52 to 5.60. The percent recovery of the amikacin estimation was 113.09 ± 4.27(n=3). Conclusion: This validated method is considered a green method, which is suitable for the routine analysis of amikacin in amikacin sulphate injections.

Core-shell nanofibers of ZnFe2O4/ZnO for enhanced visible-light photoelectrochemical performance

Recent research places significant importance on the development of innovative nanocomposites for photoelectrochemical applications. This paper presents the fabrication, characterization, and possible photoelectrochemical applications of novel ZnFe2O4/ZnO core-shell nanofibers. These core-shell nanofibers were fabricated through co-axial electrospinning using PVP solutions containing iron and zinc nitrate precursors for the core and shell. The structural and optical properties of ZnFe2O4/ZnO core-shell nanofibers were examined through TEM, SEM, XRD, FTIR, Raman spectroscopy, and diffuse reflectance spectroscopy. This comprehensive analysis unveiled that the development of core and shell characteristics was notably influenced by the interdiffusion of [Fe]/[Zn] during the annealing process. The photoelectrochemical properties of ZnFe2O4/ZnO core-shell nanofibers were assessed through electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), and the Mott-Schottky method. These core-shell nanofibers demonstrated a robust electrochemical response to visible light. Photocurrent and photoconversion efficiency of the core-shell nanofibers were calculated and compared with the corresponding values for core-shell nanoparticles. The mechanisms underlying the structural, optical, and photoelectrochemical properties of ZnFe2O4/ZnO core-shell nanofibers were discussed. These advanced nanofibers hold potential applications in photocatalysis, photovoltaics, and energy storage, making this research timely and crucial for advancing sustainable energy technologies and environmental remediation efforts.

Non-Destructive Characterization of Italian Local Brassicaceae Cultivars Using ATR-FT-IR and Chemometrics

Brassicaceae is a family of vegetables found all over the world that has been attracting the attention of researchers due to its rich chemical composition and potential health benefits (antioxidant and anti-inflammatory, as well as antimutagenic activity and potential anticarcinogenic effects). In Italy, various Brassicaceae varieties are commercially available, including traditional local cultivars, which have unique features and genetic diversity. As a result, there is a growing need to protect and recognize these landraces to preserve biodiversity. In this study, non-destructive tools such as Attenuated Total Reflectance-Fourier Transform-Infrared Spectroscopy (ATR-FT-IR) and chemometrics were employed to investigate eight distinct Brassicaceae landraces. The collected data were analyzed using a class modeling approach (Soft Independent Modeling of Class Analogy) and a discriminant classification method (Partial Least Squares Discriminant Analysis) to assess similarities and dissimilarities among the samples, all cultivated in an experimental field under the same pedoclimatic conditions. Remarkably, the combination of IR spectra and chemometric tools allowed accurate classification of the samples according only to their genetic background and despite their inclination to hybridization. The study highlights and demonstrates the importance and applicability of this specific non-destructive method for assisting the management and preservation of the genetic resources related to the local varieties of Brassicaceae.