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The structures and chemical bond evolution of ditantalum doped carbon clusters Ta2Cn−/0 (n = 1–7) were studied via size-selected anion photoelectron spectroscopy and theoretical calculations. It is found that Ta2C−/0 has a triangular structure and Ta2C2−/0 has a quasi-rhombus structure with C2v symmetry. Ta2C3− has a quasi-planar structure with a carbon atom and a C2 unit interacting with two tantalum atoms, and the lowest-energy isomer of neutral Ta2C3 has a triangular bipyramid structure with three carbon atoms around the Ta2 unit. Ta2C4−/0 has two C2 units connected with the Ta2 unit in parallel. Two isomers of Ta2C5− are observed, where both isomers have one carbon atom and two C2 units bound to the Ta2 unit in different ways. The most stable structure of neutral Ta2C5 has one carbon atom added on top of the Ta2C4 cluster. The most stable structures of Ta2C6-7−/0 can be viewed as a C2 unit and a C3 unit capping a butterfly like Ta2C4 structure, respectively. Molecular orbital analysis shows that neutral Ta2C3 has a large gap between its highest occupied molecular orbital and lowest unoccupied molecular orbital. Chemical bonding analysis reveals that the Ta–Ta interactions in Ta2Cn−/0 (n = 1–7) clusters are slightly weaker than the Ta–Ta interaction in bare Ta2 due to the participation in forming multicenter bonds. [ABSTRACT FROM AUTHOR]

We investigate the growth of Au/FexNy/MgO trilayers on GaAs(001) substrates by plasma-assisted molecular beam epitaxy. The optimization of the growth conditions made it possible to obtain the compound of stoichiometric Fe4N. Microstructural studies show that Fe4N forms 3D islands at the initial stages of growth. As the Fe4N thickness increases, a columnar growth sets in leading to a strong texturing and to the formation of grains having the same crystallographic orientation. The growth is epitaxial with the relationship GaAs (001) [110]//MgO (001) [110]//Fe4N (001) [110]//Au (012) [0–32]. A chemical analysis at the nanoscale reveals that the interfaces are rather sharp with a limited interdiffusion. Magnetic characterizations show that a trilayer containing a 1-nm-thick Fe4N layer is already ferromagnetic. The easy magnetization axis is in-plane independent of the Fe4N layer thickness (from 1 to 6 nm). This study shows the potential to use Fe4N as a spin injector for spin-optoelectronic applications. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenides possess a significant specific surface area, adjustable bandgaps, and excellent optical absorption properties, rendering them highly conducive to photocatalytic applications. Herein, a MoS2-like 2D superatomic Cd6S2 monolayer is predicted, wherein the octahedral Cd6 superatom unit connects with S atoms via six vertices. Chemical bonding analysis reveals that the remarkable dynamic, thermal, and mechanical stability of the Cd6S2 monolayer results from the covalent Cd–S bonds and the 6-center 8-electron (6c–8e) delocalized bond within the Cd6 core, which ensures the chemical octet rule for both the S atom and the Cd6 superatom. Demonstrating notable optical absorption coefficients and a strain-tuned energy band structure, the Cd6S2 monolayer emerges as a viable candidate for catalyzing the solar-powered splitting of water. This work offers an alternative avenue to modify or improve the properties of 2D materials for photocatalytic applications through superatomic assembly. [ABSTRACT FROM AUTHOR]

Graphite/SiC (GSC) thin films were synthesized on silicon substrates via a spray method, depositing a Si-graphite solution on preheated silicon samples at 350 °C, followed by annealing at 800 °C for 4 h. A systematic approach was employed to ensure the effective incorporation of graphite into the SiC material during solution preparation. Various analytical techniques, including XPS, UPS, Reflection Energy Electron Loss Spectroscopy (REELS), PL, AFM, and Hall effect measurements, were employed for comparative analysis of the chemical composition, morphological, electrical, and optoelectronic properties of as-deposited and annealed GSC films. XPS analysis revealed the presence of Si—C and graphitic bonds in the as-deposited GSC, with a significant compositional shift to oxygen-rich graphite oxide/oxycarbides after annealing. REELS demonstrated increased bandgap and bulk plasmon energy due to surface oxidation, while UPS highlighted a high electronic density in the as-deposited film, diminishing after annealing. AFM revealed a tendency of as-deposited GSC grains to form smaller, sharper structures after annealing, resulting in smoother and more homogeneous surface morphology. Phase AFM confirmed graphite incorporation at grain boundaries and within the bulk, forming a composite structure. PL spectra of the as-deposited film exhibited a broad visible emission with distinct sub-peaks linked to SiC bandgap transitions and carbon-rich defects. Chromaticity diagrams indicated suitability for white LED applications. Hall effect measurements showed excellent electrical properties of the as-deposited GSC film, with high carrier density and mobility, which reduced significantly after annealing, transitioning the material to a more insulating state. These findings collectively provide a comprehensive understanding of GSC thin films' properties and their potential applications. [ABSTRACT FROM AUTHOR]

Based upon global-minimum searches and first-principles electronic structural calculations, we present the perfectly planar B6O50/−/2− (1–3) systems. Notably, the C2v B6O50/− (1–2) clusters mark a groundbreaking advancement as the first boron oxide clusters to feature a five-membered ring. Both structures exhibit remarkable similarity, each characterized by a central B3O2 ring surrounded by three terminal BO groups. However, a notable difference lies in the bond lengths within the B3O2 core, which are uniform in the former but uneven in the latter. Detailed canonical molecular orbital and AdNDP analyses reveal the delocalized π bonds over the B3O2 ring, affirming the π aromaticity of B6O5−. The Cs B6O52− (3) cluster showcases a chain-like arrangement with three terminal BO groups and a typical OBO group linked to a B2 core, emphasizing the crucial role of electrons in shaping the structure. Detailed chemical bonding analyses reveal the presence of dual three-center four-electron (3c–4e) π hyperbonds in 3, shedding further light on its unique bonding characteristics. Moreover, this study comprehensively extends the B(BO)n0/− (n = 1–5) series and provides valuable perspectives on their structural evolution. [ABSTRACT FROM AUTHOR]

Redox control of glasses is paramount both to their fusion process and to obtaining the desired properties of high technological glasses. However, the link between melting parameters, such as temperature, furnace atmosphere, or quenching rate, and the redox state of the final products is poorly understood. In this work, in situ x-ray absorption near-edge structure (XANES) data at Ce L3-edge data were acquired at high temperatures on cerium-containing sodium aluminosilicate glasses, allowing the determination of thermodynamic constants necessary to predict the cerium redox state over a wide temperature range (900–1500 °C). The results obtained were compared to the Raman spectra of samples quenched at different temperatures. Our findings demonstrate that the quench performed was fast enough to block the cerium oxidation state, meaning the redox measured at room temperature is representative of a high temperature state. This was further verified by room temperature Raman spectroscopy, where a relationship was found between the spectra and melting conditions. Wet chemical analysis, XANES at Ce L3-edge, Raman spectroscopy, and optical absorption spectroscopy were successfully used to determine the redox state of cerium in aluminosilicates. [ABSTRACT FROM AUTHOR]

In view of the inherent pseudocapacitance, rich redox pairs (Nb5+/Nb4+ and Nb4+/Nb3+), and high lithiation potential (1.0–3.0 V vs Li/Li+), Nb2O5 is considered a promising anode material. However, the inherent low electronic conductivity of Nb2O5 limits its lithium storage performance, and the rate performance after carbon modification is still unsatisfactory because the intrinsic conductivity of Nb2O5 has not been substantially improved. In this experiment, taking the improvement of the intrinsic electrical conductivity of Nb2O5 as the guiding ideology, we prepared F-doped Nb2O5@fluorocarbon composites (F–Nb2O5@FC) with a large number of oxygen vacancies by one-step annealing. As the anode electrode of lithium-ion batteries, the reversible specific capacity of F–Nb2O5@FC reaches 150 mA g−1 at 5 A g−1 after 1100 cycles, and the rate performance is particularly outstanding, with a capacity up to 130 mA g−1 at 16 A g−1, which is far superior to other Nb2O5@carbon-based anode electrodes. Compared with other single conductivity sources of Nb2O5@carbon-based composites, the electrical conductivity of F–Nb2O5@FC composites is greatly improved in many aspects, including the introduction of free electrons by F− doping, the generation of oxygen vacancies, and the provision of a three-dimensional conductive network by FC. Through analytical chemistry (work function, UV–Vis diffuse reflectance spectroscopy, and EIS) and theoretical calculations, it is proved that F–Nb2O5@FC has high electrical conductivity and realizes rapid electron transfer. [ABSTRACT FROM AUTHOR]

It is necessary to select appropriate active parameters to ensure both the accuracy and computation efficiency before the global analysis of chemical kinetic model. This paper proposes a new method for selecting the active parameters on the base of the combination of sensitivity analysis and linear programming. Compared with the usual methods for selecting active parameters, such as the local sensitive analysis, the characteristics of the proposed method is preliminary visualization of the possible influence of the selected active parameters on the model outputs in the process of parameter selection, ensuring the reliability of the selected active parameters. Considering the computation efficiency, the number of selected active parameters can be controlled in a suitable size through combining with dichotomy or other screening techniques. In the study, the pre-exponential factors of the Arrhenius equations in the USC-Mech II model were considered as the candidate parameters and the uncertainties of the pre-exponential factors were set. Taking the ignition of ethylene for example, the 10 reactions that can increase the ignition time of ethylene under a wide range of conditions with equivalence ratio of 1, 0.1 ~ 1 MPa and 1000 K ~ 1500 K were successfully selected using the proposed method. Then, the 10 active parameters were tested in each condition. The results showed that the selected active parameters can make the ignition delay time close to the target for each condition, which reflects the reliability of active parameter selection. [ABSTRACT FROM AUTHOR]

In recent years, perfluorinated hexanone has been widely used as a fire extinguishing agent for lithium-ion batteries in China. However, it can cause corrosion of ferrous materials in LIBs/batteries, such as storage tanks, battery boxes and ferrous connectors, while extinguishing LIBs fires. Therefore, when storing or using perfluorinated hexanone, it may cause secondary disasters. In order to clarify the corrosion mechanism and the structure of the products of perfluorinated hexanone on iron, we designed experiments to obtain "iron corrosion product". Then the main components of the corrosion products were studied by various chemical analysis methods and the corrosion mechanism was proposed. The results show that the main component of "iron corrosion product" is (CF3CF2COO)3Fe, which is generated by the reaction of CF3CF2COOH, the decomposition product of perfluorinated hexanone, with iron oxides. Accordingly, it can be determined that perfluorinated hexanone has certain safety hazards when used as a lithium-ion battery fire extinguishing agent. In order to avoid the above safety hazards of perfluorinated hexanone, it is recommended that when storing and using perfluorinated hexanone, it needs to be protected from light and moisture. [ABSTRACT FROM AUTHOR]

The editorial from Analytical & Bioanalytical Chemistry expresses gratitude to the reviewers who contributed to the journal in 2024, highlighting the importance of a rigorous peer-review process. The document lists the names of numerous scientists from diverse backgrounds and nationalities who dedicated their time and expertise to review papers for the journal, emphasizing their significant contributions. The list includes researchers with surnames ranging from Verona to Zwiener, reflecting the global nature of scientific research. The document concludes with a note from the publisher, Springer Nature, emphasizing their neutrality in relation to jurisdictional claims and institutional affiliations. [Extracted from the article]

Food factories seek the application of natural products, green feedstock and eco-friendly processes, which minimally affect the properties of the food item and products. Today, water and conventional polar solvents are used in many areas of food science and technology. As modern chemistry evolves, new green items for building eco-friendly processes are being developed. This is the case of deep eutectic solvents (DESs), named the next generation of green solvents, which can be involved in many food industries. In this review, we timely analyzed the progress on applying DES toward the development of formulations, extraction of target biomolecules, food processing, extraction of undesired molecules, analysis and determination of specific analytes in food samples (heavy metals, pesticides), food microbiology, and synthesis of new packaging materials, among many other applications. For this, the latest developments (over the last 2-3 years) have been discussed emphasizing innovative ideas and outcomes. Relevantly, we discuss the hypothesis and the key features of using DES in the mentioned applications. To some extent, the advantages and limitations of implementing DES in the food industry are also elucidated. Finally, based on the findings of this review, the perspectives, research gaps and potentialities of DESs are stated. [ABSTRACT FROM AUTHOR]

Phenolic hydroxyl groups in lignin are crucial for understanding its structure, reactivity, and potential applications. Various methods have been developed for the determining phenolic groups in lignin. This study focuses on the comparison of a simple, cost-effective, and time-efficient UV–vis ionization difference technique with the highly accurate 31P NMR spectroscopy for analyzing lignin samples of different origins and isolation methods. The results were carefully evaluated, and the strengths and limitations of each method were discussed. Two eco-friendly UV–vis approaches were proposed for a rapid and comprehensive evaluation of the total phenolic-OH groups: one using a strong alkaline solution for analyzing common types of technical lignins, and another employing multipoint wavelength calculations, effective for analyzing softwood lignins regardless of the extraction method. Additionally, the research highlighted the importance of selecting appropriate model phenolic compounds to accurately assess the phenolic hydroxyl group content in lignins using the UV–vis method. Offering straightforward and rapid analysis, with results closely aligning with 31P NMR data, this method is a promising alternative for routine analysis. [ABSTRACT FROM AUTHOR]

Although analytical methodologies are known to generate pollution, universal strategies to decrease their environmental, safety, and health burdens while maintaining performance are lacking. Separation science techniques including sample preparations and chromatography require large amounts of solvent and power to separate, identify, and quantitate pure constituents from their matrices. Recent advancements to green analytical chemistry have now provided comprehensive metrics, such as the analytical method greenness score (AMGS), that allow researchers to better understand their method's environmental burden, compare it to other methods, and indicate what areas can be addressed to enhance sustainability. Here, we review approaches and technologies that can be used to green analytical separations with a focus on improving the method's analytical figures of merit. Approaches to green sample preparation are first considered including microextraction techniques in liquid, solid, and supercritical phases and the ability to automate such techniques. We focus on high-performance liquid chromatography and sub- or super-critical fluid chromatography, where it is shown that changing the column dimensions and packing can reduce environmental impact while preserving chromatographic resolution. We review equations to calculate the greenest flow rate at which to operate a separation method, then we discuss of modern ultrafast and high throughput separations. Finally, we describe digital signal processing for analytical signals as a major green technology for the first time. We observed that, using digital signal processing, an ultrafast liquid chromatographic separation of 101 components in just one minute produced an AMGS of 0.12 which is, to our best knowledge, the lowest ever reported. [ABSTRACT FROM AUTHOR]

In this study, tempeh was developed using a probiotic culture of Lactobacillus rhamnosus adjunct culture. Purposely, soybean seeds were soaked overnight at room temperature and then boiled at 100°C for 10 to 15 min. The hot beans were then spread out in a thin layer and allowed to cool to room temperature. The Lactobacillus rhamnosus culture was added to the soybeans, which were then tightly packed in perforated plastic bags and incubated at 30°C for 24 h to produce fresh tempeh. The tempeh was then analyzed for its physical, chemical, microbial, and sensory characteristics, and the data obtained was statistically analyzed. The results of the physical and chemical analysis showed that the probiotic tempeh had a slight increase in pH, ash, and protein content, while there was a significant decrease in acidity, moisture, and fat content during storage. The microbial analysis revealed that both the total plate count and probiotic count increased over time, with treatment T4, which contained a high amount of culture, exhibiting the maximum plate count and probiotic count. The sensory evaluation showed that both the treatment and storage duration significantly impacted the aroma, color, taste, and overall acceptability of the tempeh, with all sensory attributes decreasing over time. The sensory panelists rated treatment T4 the highest for overall acceptance. In conclusion, the study suggests that probiotic soybean tempeh could be a beneficial carrier for producing a product with good physicochemical properties, acceptability, high probiotic viability, and storage durability. [ABSTRACT FROM AUTHOR]

Summary: Wheat bran, oat flour, and Dictyophora indusiata powder were used to substitute wheat flour in noodle production. The objective of this study was to investigate the effects of wheat bran flour, oat flour, and Dictyophora indusiata powder on physical, chemical, sensorial, and in vitro digestibility of wheat noodles. Results indicated that the addition of wheat bran flour, oat flour, and Dictyophora indusiata powder decreased the lightness, chewiness, and the reducing sugar released during digestion of noodles, and their estimated glycaemic index. The viscosity value of noodles decreased with Dictyophora indusiata powder addition solely. The protein, and dietary fibre of wheat noodle increased at 10% Dictyophora indusiata powder, and 10% oat flour blended with wheat flour, and the estimated glycaemic index lowered significantly with the addition of 10% wheat bran flour, and 10% Dictyophora indusiata powder. [ABSTRACT FROM AUTHOR]

Heterogeneities in the phosphorus (P) content of olivine are relatively resistant to diffusive homogenization when compared with other compositional heterogeneities. Thus, heterogeneities in the spatial distribution of P can preserve petrological information about olivine crystals from the earliest stages of crystallization which have been otherwise eliminated. However, compared to independent determinations of protracted cooling timescales in slowly cooled rocks, P enrichments are so sharp as to suggest a rate of diffusive mobility that is many orders of magnitude slower than previously suggested. Here, we heat single natural olivine crystals with sharply defined P heterogeneities (0.02–0.15 wt% P 2 O 5 over 0.5 μm spatial scale) in a 1-atmosphere gas-mixing furnace for durations of 10–20 days at 1400°C, thus exposing them to conditions that should be sufficient for complete diffusive relaxation according to published P diffusivity values. However, high-precision chemical analysis of the same interior section before and after heating reveals no discernable difference in the sharpness of phosphorus concentration patterns. Therefore, diffusion chronometry applied to skeletal P enrichments in olivine currently provides erroneously short diffusive timescales. We discuss several possible causes for these discrepancies and the implications for diffusion chronometry as applied to phosphorus in olivine. [ABSTRACT FROM AUTHOR]

Identifying the dynamics of domestic open spaces remains a challenging task. This research applies an adjusted theoretical framework of activity areas to characterize domestic open spaces in the 14th–16th century a.d. in Old Dongola, Sudan. Activity areas were defined as sedimentations of residues of recurring cycles of changing actions rather than stable components of space. To identify domestic space, this research utilizes high-resolution methods: analyses of multiple chemical elements, spatial distribution of objects, and botanical remains of courtyard occupational surfaces, combined with spatial statistics using local Moran's I autocorrelation. The relationships between the remains of human and non-human actions are discussed in terms of the material affordances affecting their deposition within the archaeological layers. Application of these methods allowed for the identification of areas of domestic tasks related to high concentrations of elements, as well as clusters of tools located on their edges. Botanical data corroborated often vague identifications of activities based on geochemistry. [ABSTRACT FROM AUTHOR]

Retention prediction through Artificial intelligence (AI)-based techniques has gained exponential growth due to their abilities to process complex sets of data and ease the crucial task of identification and separation of compounds in most employed chromatographic techniques. Numerous approaches were reported for retention prediction in different chromatographic techniques, and consistent results demonstrated that the accuracy and effectiveness of deep learning models outclassed the linear machine learning models, mainly in liquid and gas chromatography, as ML algorithms use fewer complex data to train and predict information. Support Vector machine-based neural networks were found to be most utilized for the prediction of retention factors of different compounds in thin-layer chromatography. Cheminformatics, chemometrics, and hybrid approaches were also employed for the modeling and were more reliable in retention prediction over conventional models. Quantitative Structure Retention Relationship (QSRR) was also a potential method for predicting retention in different chromatographic techniques and determining the separation method for analytes. These techniques demonstrated the aids of incorporating QSRR with AI-driven techniques acquiring more precise retention predictions. This review aims at recent exploration of different AI-driven approaches employed for retention prediction in different chromatographic techniques, and due to the lack of summarized literature, it also aims at providing a comprehensive literature that will be highly useful for the society of scientists exploring the field of AI in analytical chemistry. [ABSTRACT FROM AUTHOR]

Separation/preconcentration procedures are of great importance in the elemental analysis. In this context, layered double hydroxides (LDH) have emerged as promising sorbents in dispersive solid phase extraction (DSPE) procedures. By optimizing the DSPE procedure, lower limits of detection (LOD) can be achieved, making less sensitive detection methods viable for accurate quantification of the (ultra)trace analytes. This is of significant importance from a financial standpoint, as it enables the utilization of cost-effective and readily available detection methods. The extraction procedures using LDH typically require only a few minutes to complete, with some procedures taking as little as 1.5 min. Many studies have reported techniques that eliminate the need for centrifugation, which results in time savings and reduced sample handling. This is particularly important for ultratrace analysis. However, it has been observed that the use of certified reference materials (CRM) to validate the reliability of the developed extraction procedures is often overlooked. The literature also demonstrates inconsistencies in the terminology and abbreviations employed for extraction procedures, which may cause confusion. LDH, extensively studied for various purposes, offer a wide range of modifications and can form composites with other materials, enhancing their surface characteristics and adsorption performance. The development of novel and effective nanocomposites will undoubtedly be a research objective in this field of analytical chemistry, aiming to advance the reliability of extraction procedures. Moreover, integrating of LDH-based DSPE procedures with appropriate detection methods can enable potential automation and pave the way for online applications. [ABSTRACT FROM AUTHOR]

In modern medical diagnostics, where analytical chemistry plays a key role, fast and accurate identification of pathogens is becoming increasingly important. Infectious diseases pose a growing threat to public health due to population growth, international air travel, bacterial resistance to antibiotics, and other factors. For instance, the detection of SARS-CoV-2 in patient samples is a key tool to monitor the spread of the disease. While there are several techniques for identifying pathogens by their genetic code, most of these methods are too expensive or slow to effectively analyze clinical and environmental samples that may contain hundreds or even thousands of different microbes. Standard approaches (e.g., culture media and biochemical assays) are known to be very time- and labor-intensive. The purpose of this review paper is to highlight the problems associated with the analysis and identification of pathogens that cause many serious infections. Special attention was paid to the description of mechanisms and the explanation of the phenomena and processes occurring on the surface of pathogens as biocolloids (charge distribution). This review also highlights the importance of electromigration techniques and demonstrates their potential for pathogen pre-separation and fractionation and demonstrates the use of spectrometric methods, such as MALDI-TOF MS, for their detection and identification. [ABSTRACT FROM AUTHOR]

Counterfeiting or forged imitation of banknotes is a perpetual practice engulfing global economies. This not only poses challenges for the material scientists to come forth with advanced security materials but also demands veracious forensic examination to detect counterfeits. The present article pursues novel efforts in summarizing a study that lays focus on the recent optical and analytical examinations being used for the characterization and detection of chemical profiles of authentic and counterfeited banknotes. The article briefs the trends in banknote materials, security paper manufacturing process, security inks used for printing, and types of the security printing process in banknote practices. Reported literature shows the introduction of new anti-counterfeiting materials viz. magnetically-responsive photonic anti-counterfeiting watermarks, and fluorescent nanoparticles that can be used as anti-counterfeiting inks, anti-stokes inks, metameric inks, etc. Analytical techniques such as IR spectroscopy, Raman spectroscopy, Mossbauer spectroscopy, X-ray diffraction, X-ray fluorescence, LIBS, XRF, ELDI-MS, EASI/DESI-MS, HPLC, VSC, AFM, etc. in conjunction with different chemometrics approaches have been critically discussed. The study also presents the future scope in banknote examination like the use of hyper spectral imaging and sensor-based counterfeit detection systems. [ABSTRACT FROM AUTHOR]

The field of analytical chemistry has been significantly advanced by the availability of state-of-the-art instrumentation, allowing for the development of novel applications in this field. However, in many cases, the direct interpretation of the recorded data is often not straightforward, hence some level of pre-processing is required (e.g., baseline correction, derivatives, normalization, smoothing). These techniques have become a critical first step for the successful analysis of the data recorded, and it is recommended to use them before the application of chemometrics (e.g., classification, calibration development). The aim of this paper is to provide with an overview of the most used pre-processing methods applied to instrumental analytical methods (e.g., spectroscopy, chromatography). Examples of their application in near infrared and UV-VIS spectroscopy as well as in gas chromatography will be also discussed. Overall, this paper provides with a comprehensive understanding of pre-processing techniques in analytical chemistry, highlighting their importance during the analysis and interpretation of data, as well as during the development of accurate and reliable chemometric models. [ABSTRACT FROM AUTHOR]

Green solvents (GSs) has gained significant attention in recent years due to their potential as safer and more sustainable alternatives to traditional organic solvents. Solvents are used in a wide range of applications, from industrial processes to everyday products. Solvent emissions and losses can have a significant impact on the environment and human health, which is why many initiatives are being undertaken to get rid of or switch to eco-friendly alternatives. A key area of green chemistry that led to the concept of "green" solvents is the development of alternative solvents that are less toxic and more environmentally friendly than traditional organic solvents. The advantages of using green solvents over conventional ones are their environmental friendliness, biocompatibility, biodegradability, and simplicity of preparation. Different sample preparation techniques have successfully utilized green solvents to offer a sustainable separation media for the extraction of a variety of inorganic and organic compounds which are crucial for research in environmental samples. Recent developments in green analytical chemistry (GAC) have focused on how to prepare and use samples using environmentally sustainable solvents. The current study covers the advance and currently used green solvents with an emphasis on environmentally friendly sample preparation methods. This review aims to briefly summarize the current state of knowledge about the use of green solvents particularly ionic liquids, deep eutectic solvents and switchable solvents (SSs) with the perspective of GAC in sample preparation methods. [ABSTRACT FROM AUTHOR]

Orchids are among the plant species facing the most severe threat of extinction worldwide. A better understanding of the morphological and chemical structures of their seeds would contribute to addressing the challenges encountered during seed germination and, consequently, developing more effective conservation strategies. This study conducted morphometric and FTIR chemical analyses on the seeds of Anacamptis morio (L.) R.M. Bateman, Pridgeon & M.W. Chase, Anacamptis sancta (L.) R.M. Bateman, Pridgeon & M.W. Chase, Neotinea maculata (Desf.) Stearn, Neotinea tridentata (Scop.) R.M. Bateman, Pridgeon & M.W. Chase, Orchis anatolica Boiss, and Orchis italica Poir. When evaluating the morphometric measurements of the seeds, it was observed that the genera showed distinct differences, while species belonging to the same genus clustered together. Parameters such as seed size, embryo size, and cavity percentage had a positive impact on this differentiation. The similarity of the analysed species' FTIR spectra confirms their belonging to the same family. However, the secondary order FTIR spectra clearly revealed variations in absorbance values, highlighting differences between genera and species. It was observed that species belonging to the orchid genus and the genus Anacamptis exhibited similarities among themselves, whereas N. tridentata showed distinct differences from other species. Principal Component Analysis (PCA) based on FTIR results further supported these findings. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to develop and optimize a method for evaluating the persistence of residual fragrance after body washing, addressing a significant requirement in the development of personal care products. The main objective is to establish a reliable, sensitive and reproducible analytical technique to assess fragrance longevity on skin post‐use of body wash products. Methods: Headspace solid‐phase microextraction (HS‐SPME) coupled with gas chromatography–mass spectrometry (GC–MS) is used to analyse residual fragrances. We investigate the extraction efficiencies of various SPME fibres and compare different methods for sampling skin‐emitted fragrances, including tape stripping and sealed glass funnels. A controlled body‐washing procedure is implemented to standardize the cleansing process. Results: Our findings indicate that the relative standard deviation for measuring five distinct fragrances is within the range of 3%–14%, highlighting the precision of the method. A notable variance exists in the extraction efficiency of fragrances using different types of SPME fibres, with some exhibiting over a threefold difference. Furthermore, the glass funnel method for fragrance collection demonstrates an 11.7 times greater sensitivity to galaxolide than that of the tape‐stripping method. Residual fragrances with base notes as the main components can be detected on the skin up to 24 h after body washing. Conclusion: The optimized method for residual fragrance evaluation developed in this study offers a robust tool for analysing fragrance components persisting on the skin for up to 24 h post‐wash. This advancement facilitates a deeper understanding of fragrance longevity in personal care products, enabling comparative analyses between different products. [ABSTRACT FROM AUTHOR]

Objective: European Commission Regulation (EU) n°2023/1545 introduced the concept of grouping names in the cosmetics sector in July 2023. These groups bring together allergenic substances with the same level of skin sensitization. Their purpose is to lighten the list of ingredients on cosmetic packaging, by grouping together substances deemed to be similar under the same name. As this classification is based on a single toxic effect − skin sensitization − the present study aims to analyse the relevance of these groupings with regard to other toxic effects of substances in the same group. Methods: This study was carried out by consulting an available database, various reports from 5 committees, 2 books and 5 articles in order to complete the toxicological profile of each substance. Then, in order to highlight any discrepancies within the classification, the worst cases were identified. For this purpose, the data for each substance in a group were compared, and in the event of greater criticality for a toxic effect, this was qualified as a worst case. In addition, similar toxic effects between several substances within the same group were also recorded. The aim of this additional research was to validate the definition of the grouping name and the similarities between substances in the same group. Results: From the 17 grouping names, 5 presented worst cases. Two groups had 2 worst cases and the others only one. In total, from the 7 worst cases detected, 3 were due to the toxic effect "skin irritation". In most cases, the substances in the groupings shared the presence or absence of risk. Only the degree of risk criticality varied. Conclusion: Classification by grouping names appears justified regarding the similarities between substances, particularly in terms of skin sensitization. However, the presence of worst cases qualifies it and highlights the importance of being vigilant when assessing the risk of cosmetic products including these grouping names in their list of ingredients. [ABSTRACT FROM AUTHOR]

In root research, hydroponic plant cultivation is commonly used and soil experiments are rare. We investigated the response of 12‐day‐old barley roots, cultivated in soil‐filled rhizotrons, to different soil water potentials (SWP) comparing a modern cultivar (cv. Scarlett) with a wild accession ICB181243 from Pakistan. Water potentials were quantified in soils with different relative water contents. Root anatomy was studied using histochemistry and microscopy. Suberin and lignin amounts were quantified by analytical chemistry. Transcriptomic changes were observed by RNA‐sequencing. Compared with control with decreasing SWP, total root length decreased, the onset of endodermal suberization occurred much closer towards the root tips, amounts of suberin and lignin increased, and corresponding biosynthesis genes were upregulated in response to decreasing SWP. We conclude that decreasing water potentials enhanced root suberization and lignification, like osmotic stress experiments in hydroponic cultivation. However, in soil endodermal cell suberization was initiated very close towards the root tip, and root length as well as suberin amounts were about twofold higher compared with hydroponic cultivation. Summary Statement: In soil‐grown roots of barley, the endodermal cell suberization was initiated far much closer towards the root tip, suberin amounts were almost doubled, and roots were more than twofold longer compared with hydroponics. There is a very different plastic response to water stress in soil‐grown roots compared with hydroponically cultivated roots. [ABSTRACT FROM AUTHOR]

Measurement of scalar couplings between protons is a very challenging task because of complex multiplet patterns and severe overlapping of these multiplets in congested 1D spectra. Numerous 2D J‐resolved sequences now exist that utilize either the Zangger‐Sterk or PSYCHE or z‐filter elements along with selective refocusing and pure‐shift schemes to generate high‐resolution phase‐sensitive spectra with simple doublets in F1$$ {F}_1 $$ dimension. Herein, we present a 2D J‐resolved sequence that employs a simple element consisting of hard pulses and inter‐pulse delays to generate phase‐sensitive spectra. This simple element in combination with selective refocusing eliminates all the undesired components including the intense axial peaks, thus provides clean 2D J‐resolved spectra with signals of only two targeted protons with simple doublets in F1$$ {F}_1 $$ dimension and full multiplets of target protons in F2$$ {F}_2 $$ dimension. This high selectivity thus obviates the need for extra filtering elements and pure‐shift acquisition schemes that are integrated into existing sequences to facilitate coupling measurements in overcrowded signals. It is therefore anticipated that this sequence, with the ease of implementation and ability to extract coupling values from highly congested spectra, should turn out an important tool for structural and conformational analyses in chemical and biological studies. [ABSTRACT FROM AUTHOR]

The primary objective of this review is to provide a comprehensive overview of the challenges involved in detecting ancient ayahuasca, a traditional hallucinogenic drink from the Amazon region, which is prepared using Banisteriopsis caapi liana and other plants, by utilizing advanced analytical techniques. The presence of harmine and harmaline in Andean archaeological findings has led certain authors to speculate that the Banisteriopsis liana may have been the source plant responsible for their occurrence. Consequently, the utilization of this liana can be traced back to at least 500 CE. However, a combination of archaeological, ethnobotanical, biochemical and analytical chemistry considerations has rendered uncertain the true origins of the presence of harmine and harmaline in ancient mummies and artifacts. Thus, the archaeological evidence does not convincingly prove the ancient usage of ayahuasca. [ABSTRACT FROM AUTHOR]

4-(2-amino-2-oxoethyl) phenyl 4-methylbenzenesulfonate (APMBS), a novel compound, has been synthesized and characterized by spectro-analytical techniques. X-ray diffraction data reveals it crystallizes in the triclinic crystal system with space group P 1 ¯ . The structure is stabilized through strong N–H⋯O, weak C–H⋯O and C–H⋯π hydrogen bond interactions yielding a supramolecular structure. The N1A–H1AA⋯O4A, C4–H4⋯O3, and C14–H14⋯Cg1 (Ring: C8–C13) interactions link the molecules into dimers, while the interaction C9-H9–O2 results in the formation of a molecular chain along the a-axis. The optimized structural geometry, by and large, as calculated using DFT and HF techniques is in conformity with the corresponding X-ray data. The DFT computation further aid in the follow up investigations including frontier molecular orbitals (FMOs), density of states (DOS), atomic charges, and molecular electrostatic potential surface (MEP). For a comprehensive description of various molecular intersections, Hirsheld surface and fingerprint plots analysis has been reported, besides the combined atoms-in-molecules (QTAIM) and reduced density gradient (RDG) analysis. Docking studies have been performed against the target protein Tubulin-Colchicine: Stathmin-Like Domain Complex. [ABSTRACT FROM AUTHOR]

We present ReactionMechanismSimulator.jl (RMS), a modern differentiable software for the simulation and analysis of chemical kinetic mechanisms, including multiphase systems. RMS has already been applied to problems in combustion, pyrolysis, polymers, pharmaceuticals, catalysis, and electrocatalysis. RMS is written in Julia, making it easy to develop and allowing it to take advantage of Julia's extensive numerical computing ecosystem. In addition to its extensive library of optimized analytic Jacobians, RMS can generate and use Jacobians computed using automatic differentiation and symbolically generated analytic Jacobians. RMS is demonstrated to be faster than Cantera and Chemkin in several benchmarks. RMS also implements an extensive set of features for analyzing chemical mechanisms, including a library of easy‐to‐call plotting functions, molecular structure resolved flux diagram generation, crash analysis, traditional sensitivity analysis, transitory sensitivity analysis, and an automatic mechanism analysis toolkit. RMS implements efficient adjoint and parallel forward sensitivity analyses. We also demonstrate the ease of adding new features to RMS. [ABSTRACT FROM AUTHOR]

Microfluidic technology is widely used in biomedicine, chemical analysis, and environmental improvement. Improvement of the mixing quality of low Reynolds number flows in micro-dimensional devices is essential. In this paper, we present a novel electroosmotic micromixer with twin diamond-shaped chambers and sawteeth, that can broaden the mixing space and boost the local velocity. The fluids are disturbed and folded due to the electroosmotic flow generated by electrodes on the chambers. The comprehensive analysis of the flow characteristics, the mixing performance and pressure drop of the micromixer of different parameters have been carried out. The findings demonstrate that each of these designs is good for efficient mixing, and numerous vortices are generated in the chambers. After optimizing the parameters, the best mixing efficiency can reach 99.9% in one second. The novel structure proposed in this paper provides a simple and effective method for mixing in the field of micro-total-analysis systems. [ABSTRACT FROM AUTHOR]

Iphiona grantioides (Boiss) Anderb. is a medicinal plant featuring several traditional uses. Nevertheless, this plant has not been widely investigated by modern medicinal chemistry yet, as also the properties of its extracts. In this study, we report the extraction of the essential oil by hydrodistillation from the leaves of I. grantioides. This was characterised by GC-MS analysis and ten chemical constituents were identified. Our findings demonstrate that the essential oil is effective in inhibiting the growth of bacterial strains, and of Klebsiela pneumonia and Staphylococcus aureus in particular. Additionally, its antioxidant properties were evaluated, and it showed radical scavenging activity in vitro. [ABSTRACT FROM AUTHOR]

Globally, African marigold (MG) derived essential oils (EOs) have attained an immense economic pertinence in the flavor, fragrance, food, medicinal, and floricultural industries, which necessitate boosting its production on a commercial scale. Therefore, we aimed to assess varying levels (0, 50, 100, 150, and 200 mg L-1) of exogenously applied melatonin (MT) as a growth hormone to trigger growth, flower yield, and EOs of MG. The MT was applied as a foliar spray after thirty days of transplantation of MG plants and repeated thrice at fifteen-day intervals. The results depicted that exogenous MT (150 mg L-1) recorded the maximum plant height and leaves number along with fresh and dry weights of leaves and roots. The same treatment exhibited 66%, 64%, and 18% higher flower fresh and dry weights and flower yield respectively, than the control. Additionally, MT remained effective in reducing days taken to bud emergence and flowering, while flower retention duration increased by 11 days. Following the trend of vegetative growth traits, foliar-applied MT (150 mg L-1) remained unmatched in terms of physiological attributes (transpiration rate, stomatal conductance, chlorophyll a, and b contents) of MG. Moreover, for EOs extracted from fresh and dry flowers and leaves, this treatment remained effective by producing 77%, 73%, 53%, and 85% higher content, respectively than the control. Finally, the chemical profiling analyses detected eighty-seven chemical constituents (Caryophyllene oxide was the most dominant compound, and cis-Z-alpha-Bisabolene epoxide followed it) in MG flowers. In terms of the retention time of different chemical compounds in MG flowers, Calarene epoxide had the highest retention time of 19.75 minutes among major compounds. Based on these results, 150 mg L-1 dose of MT may be recommended to growers for boosting MG growth, floral yield and EOs content sustainably. [ABSTRACT FROM AUTHOR]

The passive film on a dual-phase Al0.3Cr0.5Fe2Mn0.25Mo0.15Ni1.5Ti0.3 FCC + Heusler (L21) compositionally concentrated alloy formed during extended exposure to an applied potential in the passive range in dilute chloride solution was characterized. Each phase, with its own distinct composition of passivating elements, formed unique passive films separated by a heterophase interface. High-resolution, surface sensitive characterization enabled chemical analysis of the passive film formed over individual phases. The film formed over the L21 phase had a higher concentration of Al, Ni, and Ti, while the film formed over FCC phase was of similar thickness but contained comparatively higher Cr, Fe, and Mo concentrations, consistent with the differences in bulk microstructure composition. The passive film was continuous across phase boundaries and the distribution of passivating elements (Al, Cr, and Ti) indicated both phases were independently passivated. Spatially resolved analysis of the surface chemistry of the dual-phase CCA revealed that the cation with the highest composition in passive film formed on the FCC phase was Cr (52.4 at. pct) and for the L21 phase was Ti (53.1 at. pct) despite the bulk concentration of each element being below 20 at. pct in their respective phases. Al, Cr, and Ti were enriched in both phases within the passive film relative to their respective bulk compositions. In parallel studies, single-phase alloys with compositions representative of the FCC and L21 phases were synthesized to evaluate the corrosion behavior of each phase in isolation. The corrosion behavior of the dual-phase alloy showed passivity evidenced by a pitting potential of 0.615 VSCE in 0.01 M NaCl. The pitting potential and other electrochemical parameters suggested a combination of behaviors of both single-phase samples, suggesting that the global corrosion behavior may be represented by a composite theory applied to phases, their area fractions, and interphase length. However, the interphase in the dual-phase CCA was a local corrosion initiation site and may limit localized corrosion protectiveness. The alloy design implications for optimization of second phase structure and morphology are discussed. [ABSTRACT FROM AUTHOR]

In this study, two different ethanol-based RP-HPLC methods for assay and quantification of rivaroxaban related substances in tablets were developed, based on green analytical chemistry (GAC) principles, using the design of experiments approach. The chromatographic separation was performed on X-Bridge C18 column (250 × 4.6 mm, 5 µm particle size), using isocratic elution with ethanol : water (35:65, % v/v) for the assay and gradient elution with ethanol/water mobile phase, for related substances, with a flow rate of 1.0 mL min−1. The gradient method was optimized for the separation of three specified impurities (impurity G, impurity H, and impurity 14) and the selectivity was further confirmed using forced degradation studies. Both methods were validated in accordance with ICH guidelines. The robustness of the methods was confirmed with the Central Composite Face Design of Experiments. Analytical Eco-scale approach and AGREE metrics confirmed that both methods are in accordance with the GAC principles. The proposed ethanol-based RP-HPLC methods were applied for assay and determination of related substances in rivaroxaban 10 mg tablets obtained from three different manufacturers available on the Macedonian market. [ABSTRACT FROM AUTHOR]

Raoiella indica Hirst has rapidly and widely spread throughout the New World since 2004, primarily infesting coconut palms and interacting with the predator Amblyseius largoensis (Muma). Although A. largoensis feeds on R. indica at all stages of development, it cannot naturally reduce its population to levels that do not impact the host plant. Raoiella indica possesses dorsal setae that secrete exudates during all post-embryonic developmental stages, and females have a behavior that deliberately deposits droplets on the freshly laid egg, possibly as a defense strategy against predation in vulnerable stages. In this context, we analyzed whether the presence or absence of droplets in R. indica eggs affects predation using A. largoensis as a biological model. Thus, we evaluated whether some biological and behavioral characteristics of A. largoensis could be affected by the consumption of R. indica egg masses washed or unwashed with water. Also, we performed a chemical analysis of the droplets exuded by R. indica and provided a description of the oviposition behavior of R. indica. The predator showed a higher consumption rate and preference for washed eggs. The results suggest that the exudate droplets have defensive functions, which are incorporated by the female onto the egg during oviposition and subsequently during a patrolling behavior, as they lose their effect after being washed with water. Although the droplets do not prevent the predator from feeding, they reduce the number of R. indica eggs consumed without affecting the growth of A. largoensis. [ABSTRACT FROM AUTHOR]

The evolution of hazardous chemical accidents (HCAs) is characterized by uncertainty and complexity. It is challenging for decision‐makers to expeditiously adapt emergency response plans in response to dynamically changing scenario states. This study proposes a data‐driven methodology for constructing accident scenarios and develops a novel hybrid deep learning model for scenario deduction analysis. This model aids in accurately predicting the evolution of HCAs, enabling emergency responders to prepare and implement targeted interventions proactively. First, a framework for constructing an accident scenario database is presented, based on the time‐sequential characteristics of accident progression. This framework employs a data‐driven approach to describe the evolution process of accident scenarios. Second, a deep learning model (CNN‐LSTM‐Attention) that integrates convolutional neural network (CNN), long short‐term memory (LSTM), and attention mechanism (AM) is developed for accident scenario deduction analysis. Finally, to illustrate practical application, a scenario database for HCAs is established. A major HCA case study is conducted to demonstrate the ability of this model to analyze various scenarios, thereby improving emergency decision‐making efficiency. Compared with algorithms such as CNN, LSTM, and CNN‐LSTM, the prediction accuracy of this method ranges from 86% to 93%, signifying an improvement of over 7%. This work provides a reliable framework for supporting decision‐making in emergency management. [ABSTRACT FROM AUTHOR]

Atrazine, a human-made herbicide, is infamous for its endocrine-disrupting properties, with adverse consequences on the immune, reproductive, and nervous systems. Consequently, effective recognition of atrazine in various environments, such as water, is critically important. This work presents a precise and efficient method for detecting atrazine across various environments, utilizing a well-established electrochemical technique. A metal organic framework (MOF) ZIF-67 has been synthesized and employed as a catalyst for the electrochemical detection of the triazine herbicide atrazine. Structural, morphological, and chemical analyses were conducted to evaluate the sensing material and to elucidate the interactions between the sensor and the analyte. The ZIF-67 was then integrated on the surface of the working electrode (carbon paste electrode (CPE)) to form a ZIF-67 modified-CPE (ZIF-67/MCPE). The ZIF-67/MCPE was utilized to detect atrazine by electrochemical techniques including differential pulse voltammetry (DPV) and cyclic voltammetry (CV). The sensor demonstrated excellent sensitivity and was effective in detecting atrazine. The modified sensor demonstrated a lower limit of detection (LLOD) of 3.7 μM within a linear concentration range of 4–44 μM and exhibited a strong linear correlation efficiency of 0.97. Computational results corroborated the experimental findings, revealing that the combination of ZIF-67 with atrazine forms minor triangular structures and exhibits enhanced dynamics compared to the pristine MOF. This improvement in the crystallinity of the ZIF-67 MOF with atrazine is attributed to the negative binding energy and reduced energy gap at the interface between the MOF and atrazine. Additionally, the sensor's practical application was evaluated by testing it on sewage water and fresh liquid milk. The sensor demonstrated an exceptional ability to detect atrazine, with a recovery rate ranging from 96% to 99%. This approach holds promise for developing electrochemical or solid-state devices for real-time atrazine monitoring. [ABSTRACT FROM AUTHOR]

Reasonable construction of proton transfer channels is the key to enhancing the proton transfer process and improving the performance of proton exchange membrane fuel cells. In recent years, the construction of nanofiber composite proton exchange membranes (NCPEMs) through optimizing the nanofiber chemical micro-environment or physical structures designing has become the research hotspots in this field. Based on this, this paper started with the preparation methods of nanofibers, combined with the research work of other researchers and our research group, and mainly focused on a comprehensive review of the relevant progress in optimizing the nanofiber chemical micro-environment (acid--acid, acid--base, etc.) collocation and physical structures design (porous, hollow, vertically aligned, etc.) to construct proton transport channels and improve the performance of NCPEMs. Additionally, the future development direction of NCPEMs was also discussed. This paper was in order to provide certain reference value for further research on proton exchange membrane fuel cells. This paper provides a comprehensive review focus on the progress of the rational construction of proton transport channels through the optimization of nanofiber chemical microenvironments and physical topology to enhance the performance of NCPEM. [Display omitted] • Brief on nanofibres preparation methods and their application in PEMFCs. • Analysis of the chemical microenvironment between nanofibres and polymer matrix. • The effect of nanofibres with different physical structures on NCPEMs was analysed. • The future development direction of NCPEMs was proposed. [ABSTRACT FROM AUTHOR]

The efficient extraction of various analytes from a wide spectrum of matrices with organic solvents is still a great challenge in analytical chemistry. Especially polar and charged compounds are hard to extract in combination with neutral analytes of intermediate to low polarity. The QuEChERS method is often chosen and has been adapted not only to the analysis of food samples, but also to environmental matrices (soil, wastewater) or biota. In this study, we overcome major drawbacks of QuEChERS such as low recoveries of charged analytes and impairment of downstream analysis by high salt loads. The new extraction method, applicable to liquid and solid samples, is called SWIEET (sugar water isopropanol ethyl nitrile extraction technique). Phase separation of the otherwise miscible extraction solvents water and acetonitrile is achieved by sugaring-out instead of salting-out. Extraction efficiencies were greatly improved by adding isopropanol to the acetonitrile phase. The concentrations of the additives glucose and isopropanol, as well as temperature, were optimized by a design of experiment. Further improvement was achieved through electro- or double-extractions. For all sample types tested (surface water, wastewater treatment plant effluent, tomato, soil, and oats), recoveries and precision were higher with SWIEET than with the established QuEChERS method. From wastewater treatment plant effluent, 75% recovery on average were achieved with our SWIEET method compared to 37% with QuEChERS for a model analyte mixture with polarities of logDpH7 = − 5.7 − 3.5. Higher recoveries and lower standard deviations compared to QuEChERS were achieved especially for polar and charged analytes such as metformin. Handling proved to be easy, since there was no additional solid phase and no tedious weighing of salts. [ABSTRACT FROM AUTHOR]

AbstractMiniaturized procedures for chemical analysis give the possibility of a significant reduction in quantities of organic solvents used during isolation and determination processes. Liquid-liquid microextraction (LLME) using butanol as an extractant was investigated to selectively isolate oxytetracycline (OTC) antibiotic residues from dairy products. The optimal conditions of LLME were established after deproteinization of the samples. The isolation procedure for OTC was performed using 700 µL of butanol. The extracts were analysed by HPLC-UV and LC-MS/MS. A satisfactory analyte recovery was achieved in the range 97.6%–98.9%. The concentration of the linearity range of the studied antibiotic should allow its determination at the level of MRL values. The limit of detection during HPLC-UV and LC-MS/MS determination of OTC in milk samples was 9.9·10−8 mol L−1 (47.85 µg kg−1) and 5.7·10−9 mol L−1 (2.75 µg kg−1), respectively. The precision (1.7%–8.6%) of the methods using LLME isolation of OTC varied depending on the kind of sample and the chromatographic technique used. The developed methods were applied to the analysis of milk and cottage cheese to estimate the presence and detection of OTC content. [ABSTRACT FROM AUTHOR]

Highlights In order to optimize the reinforcing effect of nano‐SiO2 on the interface of fiber metal laminates (FMLs), the nano‐SiO2 was treated by ultraviolet irradiation and silane coupling agent for different surface properties. The interaction mechanisms of nano‐SiO2 were studied by mechanical test, chemical analysis, morphology observation, and molecular dynamics (MD) simulation. The results showed that the average failure strength of FMLs with untreated, hydrophilic and lipophilic nano‐SiO2 increases by 31.80%, 48.77%, and 51.38% compared to the FMLs without SiO2, respectively, and the interface fracture energy for those increases by 31.50%, 74.82%, and 21.47%, respectively. The disparity among the properties is primarily attributed to the surface polarity. The surface group of untreated and hydrophilic SiO2 is hydroxyl, which shows stronger attraction to resin but also easy to agglomerate, while the lipophilic is silane group that shows lower polarity, resulting in weaker attraction to resin but easier dispersion within the resin. Specifically, the surface polarity was verified by characterizing the particle center distance and the number of atoms surrounded by the particle in the two‐particle model. Moreover, the simulation revealed that nano‐SiO2 and resin molecules are mainly connected by chemical bond and hydrogen bond to transfer the load. The mechanism was explored by experiment and molecular dynamic simulation. The addition of lipophilic SiO2 increased the failure strength by 51.38%. The incorporation of hydrophilic SiO2 enhanced fracture energy by 74.82%. The polarity of the surface group of SiO2 affected the agglomeration/dispersion. The SiO2 and resin were mainly connected by chemical bond and hydrogen bond. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs), an emerging nanomaterial, have shown significant promise in the materials science. This study aims to electrochemical deposited reduce carbon dots (RCDs) and pectin (PC) scaffold on the pencil graphite electrode (PGE), resulting a multifunctional electrocatalyst support (PC/RCDs/PGE) for electroloading of the nickel nanoparticles (NiNPs) to creates the NiNPs/PC/RCDs/PGE for electrooxidation of ethanol. Comprehensive surface and structural analysis and chemical identification methods were utilized for characterization of the modified electrode. Evaluation as an electrocatalyst for ethanol oxidation in 0.1 M NaOH, demonstrated that the NiNPs/PC/RCDs/PGE shows high electrocatalytic activity (Jp = 112 mA cm−2), outperforming several comparisons modified electrodes, RCDs/PGE, NiNPs/RCDs/PGE, NiNPs/PC/PGE, and NiNPs/PGE. These findings suggest that the RCDs and PC scaffold enhances the electrocatalytic activity of the NiNPs via the increasing the surface area of electrodeposited NiNPs and synergistic effect of nanocomposite components, indicating potential for significant advancements in non-platinum ethanol oxidation electrocatalysts. [Display omitted] • The RCDs were electrodeposited at PGE by electroreduction of the synthesized CDs. •The PC was electrodeposited on/in RCDs/PGE for first time to produce PC/RCDs/PGE. •The NiNPs/PC/RCDs/PGE was prepared by electroloading of NiNPs on/in PC/RCDs/PGE. •The NiNPs/PC/RCDs/PGE was used as a potent electrocatalyst for EOR in 0.1 M NaOH. •The NiNPs/PC/RCDs/PGE displayed high electrocatalytic activity toward EOR in NaOH. [ABSTRACT FROM AUTHOR]

The ternary combination like omeprazole (OMP), amoxicillin (AMX), and rifabutin (RFB) was approved by the FDA in November 2019 for combating Helicobacter pylori infections and ulcers caused by this infection. This study aims to develop and authenticate a robust and eco-friendly RP-UPLC technique aimed at the concurrent analysis of OMP, AMX, and RFB, following ICH guidelines, Analytical Quality by Design (AQbD), and green analytical chemistry (GAC) principles. The analysis used the Thermo C18 column (100 mm × 2.1 mm, 1.7 µm), ethanol, and formic acid solution (43:57) as mobile phase with a flow rate of 0.2 ml/min at 272 nm. The method was developed based on the ICH Q14 and validated according to ICH Q2(R1) followed by Forced degradation studies under various conditions. The method showed good linearity for OMP, AMX, and RFB, with coefficient of determination (r2) of 0.9995, 0.9993, and 0.9997, respectively. Precision studies indicated low %RSD values, confirming high reproducibility. Forced degradation studies confirmed the stability of the drugs for 30 min in acid, base, and redox reactions, and they were also stable for 6 h at 105 °C in dry conditions. GAPI assessment depicted a green and yellow pictogram, AGREE scored 0.85, BAGI scored 80, and RGB12 Whiteness Assessment Tool scored 97.5%. The developed RP-UPLC-PDA technique is robust and reliable for the concurrent quantification of the triple combination. It aligns with sustainability goals, enhancing the efficiency and environmental sustainability of pharmaceutical analysis, and setting a benchmark for future analytical methods. [ABSTRACT FROM AUTHOR]

The application of machine learning models in chemistry has made remarkable strides in recent years. While analytical chemistry has received considerable interest from machine learning practitioners, its adoption into everyday use remains limited. Among the available analytical methods, Infrared (IR) spectroscopy stands out in terms of affordability, simplicity, and accessibility. However, its use has been limited to the identification of a selected few functional groups, as most peaks lie beyond human interpretation. We present a transformer model that enables chemists to leverage the complete information contained within an IR spectrum to directly predict the molecular structure. To cover a large chemical space, we pretrain the model using 634,585 simulated IR spectra and fine-tune it on 3,453 experimental spectra. Our approach achieves a top–1 accuracy of 44.4% and top–10 accuracy of 69.8% on compounds containing 6 to 13 heavy atoms. When solely predicting scaffolds, the model accurately predicts the top–1 scaffold in 84.5% and among the top–10 in 93.0% of cases. Infrared spectroscopy stands out as an analytical tool for its affordability, simplicity, and accessibility, however, its use has been limited to the identification of a select few functional groups, as most peaks lie beyond human interpretation. Here, the authors use a transformer model that enables chemists to leverage all information contained within an IR spectrum to directly predict the molecular structure. [ABSTRACT FROM AUTHOR]

PM2.5 samples were collected in Suncheon during the summer (June 2–11, 2023) and winter (January 15–21, 2024). The chemical composition analysis included carbonaceous components (OC, EC), secondary ionic components (NH4+, NO3−, SO42−), dithiothreitol - oxidative potential (QDTT-OP), and volatile organic compounds. Results showed higher summer PM2.5 concentrations due to photochemical reactions and higher winter concentrations from heating and stable atmospheric conditions. The OC/EC ratio indicated greater secondary organic aerosol formation in summer. Oxidative potential (QDTT-OPv) was higher in summer (0.12 µM/m³) than winter (0.09 µM/m³), correlating strongly with OC in summer. Health risk assessment of BTEX revealed higher concentrations in winter, with benzene as the primary contributor to lifetime cancer risk (LTCR). The cumulative hazard quotient (HQ) was higher in winter, indicating increased non-carcinogenic risk. The study highlighted that oxidative potential is more influenced by chemical composition than physical characteristics, suggesting that regulating PM2.5 concentration alone may be insufficient. VOCs, as precursors of SOA, showed a positive correlation with QDTT-OPv, with benzene exhibiting the strongest correlation in winter. These findings emphasize the need for targeted management of specific PM2.5 components to mitigate health risks effectively. [ABSTRACT FROM AUTHOR]

An effective tannic acid-incorporated polyvinylpyrrolidone/polyvinyl alcohol composite hydrogel with high-potential sorption capacity was developed for the removal of copper from aqueous solution. The composite hydrogel exhibited pH-dependent swelling, in which swelling and shrinking occurred reversibly with adjustment of the pH of the medium. At pH 4, the maximal adsorption capacity for copper at 30 °C was 297.0 mg g-1, and the adsorbent dose was 4 g L-1. The adsorption kinetics were best fitted with a pseudo-second order kinetic model. The adsorption behavior was well predicted by the Freundlish isotherm. The thermodynamics parameters indicated a spontaneous and exothermic reaction with an increase in the entropy of the system. The chemical changes in the film structure before and after adsorption treatment were characterized by Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS). The FTIR, XPS and XAS results confirmed that Cu bound to the oxygens in the -OH, C = O and N-(C = O)- functional groups on the T-HD. XAS analysis revealed the chemical composition and molecular geometry of the adsorbed copper ions. The single-solute adsorption and coadsorption mechanisms, which provide insight into cobalt-copper, nickel-copper, or nickel-cobalt-copper complex solutions, were investigated. The composite hydrogel exhibited excellent regeneration ability in EDTA solution. Notably, the adsorbent retained an adsorption efficiency exceeding 87% even after five regeneration cycles. On the basis of both adsorbent characteristics and adsorption performance, it was determined that the composite hydrogel has the potential to be used as a platform for developing materials to treat wastewater containing high levels of metal contaminants such as those from the electroplating industry. [ABSTRACT FROM AUTHOR]

Phenothiazine derivative N‐(4‐bromophenyl)‐10H‐phenothiazine‐10‐carboxamide (BPC), a novel compound is selected for the present study based on the reported effectiveness of phenothiazine towards neurodegenerative diseases. Synthesis and characterization of BPC are carried out in the present work. To comprehend the electronic and structural aspects of BPC, quantum chemical studies are performed. Computational aspects using the density functional theory method using B3LYP/6–31 G ++(d,p) as a basis set are studied for the geometry optimization of the molecule. To analyze the reactivity, stability, and intramolecular interactions of the compound frontier orbital molecular analysis, molecular electrostatic potential distribution, and Fukui function are implemented. Calculations have been made to determine the electrophilic and nucleophilic descriptors of the title compounds by Fukui function evaluations on atomic charges. To visualize and quantify the localization of electrons and molecular orbitals in the molecule, electron localization function, localized orbital locator analysis and orbital localization analysis are carried out for a better understanding of chemical bonding. Basin Analysis is used for analysis of the nature of chemical bonds and interactions. To understand bond strengths, hyperconjugation, and reactivity natural bond orbital analysis is performed. [ABSTRACT FROM AUTHOR]

The objective of this work was to synthesize a new catalyst x-MoO 3 /Ni 0.5 Zn 0.5 Fe 2 O 4 using the combustion reaction method and to evaluate its catalytic potential and reuse in biodiesel production from waste oil, optimizing the process through experimental design. The catalysts were characterized in terms of structure by X-ray diffraction and phase quantification by Rietveld refinement, surface area by the Brunauer-Emmett-Teller technique, experimental density by helium pycnometry, acidity tests by ammonia desorption at programmed temperature, chemical analysis by X-ray fluorescence, morphology by scanning and transmission electron microscopy, and catalytic properties. The products of the simultaneous transesterification and esterification reactions were characterized by gas chromatography and acidity index. The results indicate the formation of catalysts with surface area ranging from 1.5 to 1.7 m2/g and density ranging from 4.5 to 5.1 g/cm3, composed of major crystalline phases of MoO 3 in the orthorhombic configuration and cubic Ni 0.5 Zn 0.5 Fe 2 O 4 ferrite, with total acidity ranging from 70 to 182 μmol/g of NH 3. Morphological characterization revealed that the catalyst comprises irregular plates of various sizes and shapes with a wide range of cluster sizes. In the simultaneous transesterification and esterification reactions of residual oil, the catalysts were active under all conditions tested, with emphasis on the catalyst containing 50 % Mo ions and 50 % Ni 0.5 Zn 0.5 Fe 2 O4 presenting the best catalytic performance with a conversion of 95 % in ethyl esters and a reduction of 71 % in acidity, with a service life of 6 cycles, an average conversion of 90 % and good thermal and structural stability after use. The experimental design was significant and predictive, with a confidence level of 95 %. Statistical analysis identified that all input variables (temperature, time, and amount of catalyst) were significant for the adopted design. The new catalyst composed of molybdenum, iron, nickel, and zinc has a positive impact on biodiesel synthesis from frying oil and ethanol. [ABSTRACT FROM AUTHOR]