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The use of mineral-based fillers tends to reduce the mechanical properties of paper, which can limit their application. The filler surface modification is a significant treatment to overcome this limitation. This research aims to offer a novel modified mineral-based filler to provide its industrial application. The surface of precipitated calcium carbonate (PCC) was modified with xylan (XS), which is a type of hemicellulose, a polysaccharide consisting mainly of xylose residues. It is used as a filler at different filler dosage levels in paper pulp. Modified PCC(MPCC) was characterized with Fourier transform infrared spectroscopy, Thermogravimetric analysis, X-ray photoelectron spectroscopy, X-ray diffraction and Field-emission scanning electron microscopy analyses. The analysis demonstrated that the MPCC filler surface was coated with XS successfully. The effect of PCC and MPCC-filled hand-sheet paper physical, chemical and optical properties were studied. The experimental results showed that the mechanical (tensile, burst, tear strength) and optical (brightness, opacity) of hand-sheet paper filled with MPCC were significantly improved compared with unmodified PCC-filled paper at the same ash content. The filler retention of PCC and MPCC fillers in paper was investigated, and the MPCC filler showed better filler retention properties in paper stock than the PCC filler. [ABSTRACT FROM AUTHOR]

The natural polymer cellulose exhibits significant potential for various applications due to its unique optical, electronic, and chemical properties. However, the use of cellulose materials in luminescent applications has been relatively limited. This study aims to develop a simple and efficient method to enhance the fluorescence of cellulose materials by incorporating rare earth elements, thereby expanding their range of applications. In this work, we synthesized hybrid cellulose materials by grafting Eu‐bpy (H2bpydc=2,2‐bipyridine‐5,5‐dicarboxylic acid) onto the surface of cellulose fibers through a straightforward post‐processing procedure, resulting in materials with excellent fluorescence properties. By leveraging the abundant hydroxyl groups on the surface of cellulose fibers, Eu‐bpy@CF exhibits high luminescence in response to relative humidity and pH changes, with a noticeable color shift from light red to red visible to the naked eye. Consequently, these materials were further applied in the construction of smart fluorescent switches for the highly accurate and selective detection of phenylenediamine. Our research provides a simple approach to creating environmentally responsive handheld fluorescent papers and expands the diversity of rare‐earth cellulose fibers for developing new fluorescent materials with smart functions. [ABSTRACT FROM AUTHOR]

In this work, a low-cost and eco-friendly paper-based analytical device (PAD) method is described for the determination of phyto-cannabinoids in cannabis and oral fluids based on a simple colorimetric reaction. The PAD was able to distinguish tetrahydrocannabinol (THC)- and cannabidiol (CBD)-rich plant samples by using 4-aminophenol (4-AP) and later on to quantify total phyto-cannabinoid content (THC + CBD + CBN) in plant and oral fluids by using the Fast Corinth V reagent. The chemical and physical properties regarding paper type and reagent concentration in the PAD were optimized to achieve the best analytical performance. After that, analytical features were obtained, including a linear range of 0.01–0.1 mg mL−1, a limit of detection (LOD) of 0.003 mg mL−1, and a suitable precision, expressed as relative standard deviation (RSD) lower than 10%. Furthermore, no significant interferences were observed in colorimetric reactions when tea, herbs, and drug samples were analyzed. Additionally, the PAD proved color stability up to 1 month after the sampling at 25 °C. The developed PAD was suitable for determining total phyto-cannabinoid content in plants and oral fluids, obtaining good results compared to GC–MS. Overall, this method showed good reliability resulting in an operational on-site device for drug monitoring. [ABSTRACT FROM AUTHOR]

Purpose: The main aim of this study is to study the effect of alkyl dimethyl benzyl ammonium chloride on removing stains, yellowness and harmful metal ions on historical printed paper, as well as the effect of this cleaner on optical and chemical properties of treated paper. Design/methodology/approach: The assessments after and before treatment were carried out using digital microscopy, infrared spectroscopy (FTIR), pH measurement, color change and finally scanning electron microscopy. Findings: The results showed that the concentrations used under study (1% and 3%) cleaned the paper efficiently without any observed effect on the chemical composition of cellulose, which was confirmed by IR spectra. The most stains that completely disappeared were the soil spots, also the pH values had improved significantly after treatment, which confirms that the detergent is effective in neutralizing the acidity of cellulose. Moreover, the color change revealed an increase in the chromatic lightness of the paper after treatment, which agreed with the results of the scanning electron microscopy examination, as the paper appeared free of dirt, and the fibers and bundles became more cohesive. Originality/value: To the best of the authors' knowledge, this study is a unique study, as there is no previous literature that has indicated the use of the effect of alkyl dimethyl benzyl ammonium chloride washing treatments for printed historical paper, as it was limited only to making disinfection materials and water purification products. [ABSTRACT FROM AUTHOR]

This document is an exclusive review of catalytic materials and their applications in various fields. It includes reviews on topics such as enzyme-nanoparticle immobilization for biocatalysis, the catalytic activity of gold enzymes, nickel single-atom catalysts for hydrogenation and dehydrogenation reactions, heterogeneous catalysts for oxime hydrogenation, advanced oxidation processes for water and air purification, and selective catalytic reduction technology for reducing NOx emissions from diesel engines. The reviews provide insights into the synthesis, structure, and application of different catalytic materials, highlighting their potential in solving technological challenges in sensing, catalysis, and biomedicine. [Extracted from the article]

Ageing of paper is a complex process of great relevance for application purposes because of its widespread use as support for information storage in books and documents, and as common low-cost and green packaging material, to name a few. A key factor in paper ageing is the oxidation of cellulose, a macromolecule of natural origin that constitutes the main chemical component of paper. Such a complex process results in changes in the cellulose polymeric chains in chemical and structural properties. The scope of this work is to explore the effects of oxidation of cellulose as one of the principal mechanisms of ageing of paper using a fluorescence-based approach. To this aim, fluorescence-lifetime imaging microscopy (FLIM) measurements on pure cellulose samples stained using Carbotrace 680 dye were performed, and data were analyzed by phasor approach. The comparison with results from conventional techniques allowed to map paper microstructure as a function of the sample oxidation degree correlating the fluorescence-lifetime changes to cellulose oxidation. A two-step oxidation kinetics that produced specific modification in paper organization was highlighted indicating that FLIM measurements using Carbotrace 680 dye may provide a simple tool to obtain information on the oxidation process also adding spatial information at sub-micrometric scale. [ABSTRACT FROM AUTHOR]

This document is a contents list for the New Journal of Chemistry, a publication by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. It includes titles and authors of various articles covering topics such as hydrogenation products of fatty acids, macrocycles obtained from condensation reactions, and the characteristics of copper(II) Schiff base complexes as antimicrobial agents. Other papers mentioned in the document discuss catalytic hydrogenation, drug encapsulation, and the removal of pollutants from water. The document includes three papers and a correction, covering topics such as the synthesis of diaminoacetylene, the Z-scheme of 2D structured BCN and Ti MOF heterojunctions for photocatalytic hydrogen evolution, and the crafting of flexible film photocatalysts for formic acid production from CO2 and cyclization of thioamides. [Extracted from the article]

As the understanding of natural gas hydrates as a vast potential resource deepens, their importance as a future clean energy source becomes increasingly evident. However, natural gas hydrates trend towards secondary generation during extraction and transportation, leading to safety issues such as pipeline blockages. Consequently, developing new and efficient natural gas hydrate inhibitors has become a focal point in hydrate research. Kinetic hydrate inhibitors (KHIs) offer an effective solution by disrupting the nucleation and growth processes of hydrates without altering their thermodynamic equilibrium conditions. This paper systematically reviews the latest research progress and development trends in KHIs for natural gas hydrates, covering their development history, classification, and inhibition mechanisms. It particularly focuses on the chemical properties, inhibition effects, and mechanisms of polymer inhibitors such as polyvinylpyrrolidone (PVP) and polyvinylcaprolactam (PVCap). Studies indicate that these polymer inhibitors provide an economical and efficient solution due to their low dosage and environmental friendliness. Additionally, this paper explores the environmental impact and biodegradability of these inhibitors, offering guidance for future research, including the development, optimization, and environmental assessment of new inhibitors. Through a comprehensive analysis of existing research, this work aims to provide a theoretical foundation and technical reference for the commercial development of natural gas hydrates, promoting their safe and efficient use as a clean energy resource. [ABSTRACT FROM AUTHOR]

This article discusses the practical applications of nanoparticles (NPs) in various fields, such as medicine, cosmetics, catalysis, and environmental protection. The properties of NPs are influenced by their size, shape, and composition, and their use in catalysis can greatly enhance their activity and efficiency. This special issue focuses specifically on the application of NPs in catalysis for environmental protection, including processes such as the oxidation of volatile organic compounds, hydrogen production, CO2 reduction, wastewater treatment, and soot oxidation. The article expresses gratitude towards the reviewers and authors who contributed to the special issue, acknowledging their time and effort in reviewing the papers and appreciating the high-quality research and review papers submitted. [Extracted from the article]

Jabon (Anthocephalus cadamba) is a promising plant species with straight, visually pleasing trunks that can be harvested at a young age as a resource for pulp and paper production due to the rapid growth rate possessed. Therefore, this study aims to investigate the chemical composition and fiber biometry of 3, 6, and 9-year-old Jabon wood, determining their suitability as a pulp and paper raw material. Samples were collected from both stem and branch sections and analyzed according to the Tappi standard. Fiber cell maceration was conducted to enable the precise measurement of fiber dimensions and derivatives. The results showed high cellulose, holocellulose, and lignin content in Jabon wood, with low to moderate levels of extractives and ash. Additionally, the crystallinity index (CrI) increased with age, particularly from 3 to 9 years old. The branch of the plant, with Grade II fiber derivative quality, had lower CrI compared to the stem, while the inner stem showed a lesser value than the outer part. In conclusion, 3-year-old Jabon wood is a potential raw material for pulp and paper production. [ABSTRACT FROM AUTHOR]

The paper considers the current state of Platinum Group Elements (PGEs) geochemistry in the ocean. The behavior of PGEs in the aquatic environment is defined by their oxidation state, the ability to change it, and complexation. The difference in chemical properties leads to PGEs fractionation in the ocean. This is their characteristic feature, along with their ultra-low contents. The paper describes the sources of PGEs supply to the ocean, PGEs behavior in the river–sea mixing zone, and their distribution in seawater. The processes of PGE accumulation in sediments, seafloor sulfides, and ferromanganese deposits of the ocean are reviewed. Possible mechanisms of PGE accumulation on ferromanganese oxyhydroxides are discussed. [ABSTRACT FROM AUTHOR]

This paper presents the agroproductive differences between two luvisol units at the Preajba Experimental Center, Gorj, Romania, under the influence of surface erosion. Thus, two soil profiles were comparatively executed, one on the plateau on a slope of 2-5%, on a typical luvisol characterized by an Aţel, Ao, AE, El, Bt1, BC, C profile, and another in the lower third of the slope on a 10-15% where a stagnic eroded luvisol was identified. The latter had gradually removed its upper horizons due to slow surface geological erosion, exhibiting a shorter profile with the AoEl, El, Bt1w, Bt2w sequence. By washing the fertile topsoil year after year, the physical and chemical properties of the soil worsened. In this regard, the bonitation sheets were drawn up, the potential yields achieved under natural conditions were determined, and following the application of specific hydro-ameliorative measures and the execution of enhanced bonitation based on them, it was observed that the bonitation scores increased, the favourability classes decreased, and the yields increased directly proportional to the value of the enhanced bonitation score. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are actively explored as sensing materials owing to their high porosity, substantial surface area, and structural diversity, providing diverse chemical and physical properties. Their fluorescent characteristics are pivotal, enabling MOFs to function as probes for detecting specific target molecules. Unlike conventional disease diagnosis methods such as biopsies or blood collection, the detection of pathogenic biomarkers in human urine is conventional and less risky. While mass spectroscopy identifies proteins and metabolites in urine at high costs, MOF test papers offer a convenient solution. These papers confirm the existence of the target molecules through naked‐eye observation upon UV light irradiation at specific wavelengths. MOF‐based fluorescent probes facilitate disease diagnosis, including pheochromocytoma, toluene exposure, vitamin deficiencies, gout, hyperuricemia, cancers, body disorders, and teratogenicity, with low detection limits. This review delves into recent developments in MOF fluorescent probes, covering synthesis, emission spectra, and sensing mechanisms. [ABSTRACT FROM AUTHOR]

Switchable solvents (SS) are a class of liquids with the unique ability to significantly alter their physical properties in response to external stimuli such as changes in temperature or the introduction or removal of CO2 gas. This reversible behaviour allows them to return to their original state with minimal changes, making them highly advantageous for various applications. A notable example of a switchable solvent is waste carbon dioxide gas, which is non‐toxic, non‐flammable, and cost‐effective. The versatility of switchable solvents extends to their polarity and physical states, which can be modified through molecular adjustments, opening new pathways for research and industrial applications. This review provides a comprehensive overview of switchable solvents, including their classification, history, properties, and applications, with a particular focus on their role in green chemistry. The types of switchable solvents discussed include Switchable‐Polarity Solvents (SPS), Switchable‐Hydrophilicity Solvents (SHS), and Switchable Water. Each type is examined in terms of synthesis, chemical properties, and development. The desirable properties of switchable solvents, such as their efficiency and recyclability, make them suitable alternatives to traditional solvents in various fields. Their applications range from water treatment and oil extraction to cleaning solid particles and recovering residual motor oil. Additionally, switchable solvents have proven effective as reaction media and in recovering polystyrene from foam. This paper also highlights the environmental benefits of switchable solvents, emphasizing their role in reducing the ecological impact of chemical processes. The potential for future developments in this field is significant, with ongoing research aimed at enhancing their performance and expanding their applications. By providing a detailed analysis of switchable solvents, this review aims to support researchers and industry professionals in developing more sustainable and efficient chemical processes. [ABSTRACT FROM AUTHOR]

The prospect of discovering a cure for cancer has been present for the past two to three decades. Annually, this illness affects approximately 10 million individuals worldwide. Anticancer medications are pivotal in treating cancer and other malignant diseases. In this paper, the physical properties and chemical reactions associated with the anticancer medications of various topological indices (TIs) have been established. Additionally, we have discussed the degree-based TIs and their Quantitative Structure-Property Relationship (QSPR) analysis. In mathematical chemistry, molecular descriptors are essential, particularly for researchers investigating Quantitative Structure-Activity Relationship (QSAR) and QSPR models. The goal of the QSPR study is to establish a mathematical relationship between the properties under investigation (such as boiling point and flash point) and various descriptors related to the molecular structure of the drugs. Furthermore, we show the correlation with the physicochemical properties of anticancer medications. [ABSTRACT FROM AUTHOR]

Allenes represent a distinctive class of organic molecules characterized by their unique physical and chemical properties. Among them, chiral allenes play a significant role in modern chemistry. They not only serve as pivotal frameworks for natural products and drug molecules but also are essential building blocks in organic synthesis. Over the years, numerous remarkable and efficient methods have been developed for the synthesis of chiral allenes. Notably, the catalytic synthesis of chiral allenes using transition metals in conjunction with chiral ligands has garnered considerable attention. This review paper aims to provide an overview of recent advancements in the synthesis of chiral allenes through asymmetric 1,4‐difunctionalization of 1,3‐enynes, in which two distinct strategies including non‐radical and radical processes are highlighted. [ABSTRACT FROM AUTHOR]

Fused filament fabrication (FFF) is a key extrusion-based additive manufacturing (AM) process for fabricating components from polymers and their composites. Functionally gradient materials (FGMs) exhibit spatially varying properties by modulating chemical compositions, microstructures, and design attributes, offering enhanced performance over homogeneous materials and conventional composites. These materials are pivotal in aerospace, automotive, and medical applications, where the optimization of weight, cost, and functional properties is critical. Conventional FGM manufacturing techniques are hindered by complexity, high costs, and limited precision. AM, particularly FFF, presents a promising alternative for FGM production, though its application is predominantly confined to research settings. This paper conducts an in-depth review of current FFF techniques for FGMs, evaluates the limitations of traditional methods, and discusses the challenges, opportunities, and future research trajectories in this emerging field. [ABSTRACT FROM AUTHOR]

Context: The electron localization is a concept that allows scientists to better understand the physical and chemical properties of electronic systems. It is associated with the propensity of electron pairs with opposite spins to accumulate as well as with their response to external perturbations. This paper contains a detailed description of the design and implementation of the program KLD, which was primarily developed in our research group to elucidate electron localization in molecular systems by evaluating the information content of electron-pair density functions. KLD employs two information-based functions as a real space measure of the Fermi and Coulomb holes for same-spin electrons and shows a better resolution as compared to other methods (i.e., ELF). Information about the acceleration of the code is also included in the present work, being noticeable the reduction of wall-time calculation and the error calculation between versions. Methods: KLD was designed to be easy to use, extend, and maintain; thus, many principles of modern software development, extensive testing, and package management were adopted. The latest version of the KLD program was created utilizing the Compute Unified Device Architecture (CUDA) version, which allows it to use the computational capacity of NVIDIA Graphics Processing Units (GPUs) for processing purposes. The electron-pair conditional density was calculated from the canonical molecular orbitals obtained at the HF/6-31G(2df,p) level, or alternatively the natural orbitals in the case of explicit correlated wavefunctions computed at the MP2/6-31G(2df,p)//HF/6-31G(2df,p) level. [ABSTRACT FROM AUTHOR]

ABSTRACT Trilinearity is a property of some chemical data that leads to unique decompositions when curve resolution or multiway decomposition methods are used. Curve resolution algorithms, such as Multivariate Curve Resolution–Alternating Least Squares (MCR‐ALS), can provide trilinear models by implementing the trilinearity condition as a constraint. However, some trilinear analytical measurements, such as excitation–emission matrix (EEM) measurements, usually exhibit systematic patterns of missing data due to the nature of the technique, which imply a challenge to the classical implementation of the trilinearity constraint. In this instance, extrapolation or imputation methodologies may not provide optimal results. Recently, a novel algorithmic strategy to constrain trilinearity in MCR‐ALS in the presence of missing data was developed. This strategy relies on the sequential imposition of a classical trilinearity restriction on different submatrices of the original investigated dataset, but, although effective, was found to be particularly slow and requires a proper submatrix selection criterion. In this paper, a much simpler implementation of the trilinearity constraint in MCR‐ALS capable of handling systematic patterns of missing data and based on the principles of the Nonlinear Iterative Partial Least Squares (NIPALS) algorithm is proposed. This novel approach preserves the trilinearity of the retrieved component profiles without requiring data imputation or subset selection steps and, as with all other constraints designed for MCR‐ALS, offers the flexibility to be applied component‐wise or data block‐wise, providing hybrid bilinear/trilinear models. Furthermore, it can be easily extended to cope with any trilinear or higher‐order dataset with whatever pattern of missing values. [ABSTRACT FROM AUTHOR]

AbstractOvotransferrin(OVT)is a protein found in many types of egg white and has a wide range of functional properties. It has 50% homology with human/bovine lactoferrin, and is expected to be one of the most important alternative proteins for use in food and nutritional applications. This paper mainly reviews the structural characteristics and chemical properties of OVT, as well as its extraction and purification methods. It also systematically describes the various biological activities of OVT and its applications in food and medical industries. The challenges and limitations in the research of OVT were suggested. This review recommends some possible methods such as nanoparticle carriers and microencapsulation to improve the bioavailability and stability of OVT. In addition, this review highlights several strategies to overcome the limitations of OVT in terms of preparation and purification. This review systematically summarizes the recent advances in OVT and will provide guidance for the its development for food and nutritional applications. [ABSTRACT FROM AUTHOR]

In this paper, the method for the fabrication of nanofibers based on poly(vinyl alcohol) (PVA) with controlled characteristics and surface morphology from binary solvent systems has been developed. Based on the Hildebrand–Scatchard theory of solubility, the calculated Teas diagrams, which take into account intermolecular interactions, made it possible to predict the formation of low-defect nanofibers based on PVA in systems of binary solvents with a higher proportion of hydrogen bonds. As a result of the findings, ethanol was determined to be a "inappropriate" solvent for the electrospinning PVA solution, whereas water and acetic acid displayed the properties of a "appropriate" solvent. The decrease in the volume of the unit cell with a slight decrease in the overall degree of crystallinity of the substance demonstrated the dependence of the change in the crystallization mechanism during the formation of PVA nanofibers on the transition from an individual aqueous polymer solution to the water/acetic acid binary solvent system. Compared with the results obtained during the PVA nanofibers fabrication from aqueous solution, the addition of 35% by weight of acetic acid to the aqueous solution of 8 wt% PVA allowed to lower the voltage from 30 to 26 kV and to increase the fiber fabrication yield by the increase in the flow rate from 0.2 to 0.3 mL/h. We confirmed that acetic acid has no effect on the chemical properties of PVA nanofibers however did change their lattice structure and reduce crystallinity of nanofibers. Such safe systems with controlled properties are suitable ones for biological active compounds encapsulation for drug delivery. [ABSTRACT FROM AUTHOR]

This paper aimed to provide technical support for fuel management by exploring different strengths of fuel removal on the physical and chemical properties and flammability of Betula platyphylla forests in the wildland–urban interface. After investigating the northeastern region during the forest fire prevention period in May 2023, a typical WUI area was selected, and three different treatment strengths, combined with a control, were set up to carry out indoor and outdoor experiments for 27 weeks. Compared with previous studies, this study mainly investigated and analyzed the dynamic changes in the physical and chemical properties and fuel flammability after different intensities of treatments on a time scale. By processing and analyzing the data, the following results were obtained. Significant differences existed in the fuel loading of different time-lag fuels over time (p < 0.05). The ash and ignition point of 1 h time-lag fuel after different treatment intensities generally increased first and then decreased, and the higher heat value and ash-free calorific value generally decreased first and then increased. The physical and chemical properties of 10 h and 100 h time-lag fuel fluctuated with time, but the overall change was insignificant. The indicator that had the greatest impact on the combustion comprehensive score for different time-lag fuels was fuel loading. The change in the flammability of dead surface fuel with time varied significantly, and different treatment intensities effectively reduced the fuel's flammability. The reduction effects, presented in descending order, were as follows: medium-strength treatment > low-strength treatment > high-strength treatment > control check. In conclusion, different treatment intensities have significant effects on the flammability of the fuel, and the medium-strength treatment has the best effect. Considering the ecological and economic benefits, adopting the medium-strength treatment for the WUI to regulate the fuel is recommended. [ABSTRACT FROM AUTHOR]

Study of chemical properties of water radical cations is of great significance for elucidating related reactions process. In this paper, the reaction characteristics of (H2O)2+• prepared online with several benzene derivatives were investigated. The results showed that, when (H2O)2+• reacted with aromatic compounds without electron-withdrawing groups, such as benzene (C6H6, 78 u), anisole (C7H8O, 108 u) and 2,4-dimethylaniline (C8H11N, 121 u), the corresponding phenol product ((C6H5OH) +•, m/z 94), (C7H7O−OH)+•, m/z 124) and (C8H10NOH+H)+, m/z 138)) were observed, accompanied with the production of electron transfer (ET) products (C6H6) +•, (C7H8O) +•) or proton transfer (PT) product ((C8H11N+H)+). Isotope labeling experiments proved that OH in corresponding phenol products was originated from (H2O)2+•. Interestingly, when (H2O)2+• reacted with substituted benzenes bearing strong electron-withdrawing group, such as benzonitrile (C6H5CN, 103 u) and nitrobenzene (C6H5NO2, 123 u), the main products were the radical substituted adducts (C6H5CN+ H2O)+• (m/z 121) and (C6H5NO2+H2O)+• (m/z 141), respectively, without phenol products or substituted benzene radical cation were noticed. It was obvious that the reaction between (H2O)2+• and the substrate occurred through four competing processes: (a) electron transfer (ET) reaction, in which aromatic compounds release an electron to (H2O)2+• to from an aromatic radical cation; (b) proton transfer (PT) reaction in which aromatic compounds got a proton derived from the dissociation of (H2O)2+•; (c) dissociative electron transfer (DET) reaction, accompanied with the electron transfer process, C−H bond cleavage and C−OH bond formation; (d) radical substitution reaction in which a radical cation adduct consisting of aromatic molecule and H2O generates. It was speculated that the diverse reactivity of (H2O)2+• was owe to its two interchange structures ((H2O)H+−•OH and [H2O∴OH2]+•) generates. It was proposed that the electron withdrawing groups on the aromatic ring would benefit for the existence of two-center and three-electron structure of (H2O)2+• and induced the radical substitution reaction. In contrary, compounds without electron withdrawing groups or bearing electron donating groups on the aromatic ring would contribute to the presence of proton transfer structure of (H2O)2+• (containing H+ and •OH) and facilitate the C−OH bond formation. This study will help to elucidate the chemical reaction processes involving benzene or substituted benzenes and (H2O)2+•. [ABSTRACT FROM AUTHOR]

Monte Carlo simulations are commonly used to model the behavior of chemical species of the heaviest elements and their homologs in gas chromatography experiments. In this paper, we present an extension of the fundamental Monte Carlo simulation proposed by Zvara in 1985. While preserving the core functionality, our code features two enhancements: first, it allows simulating experiments in which a primary radioisotope decays into a daughter isotope belonging to a different element, hence exhibiting different chemical properties. Second, it allows modeling scenarios where conversion of an initial chemical species to a different one can occur at temperatures high enough to overcome an activation barrier, facilitating simulations of related physisorption and chemisorption processes. This Monte Carlo code is applicable to open tubular and rectangular chromatography columns. [ABSTRACT FROM AUTHOR]

SiC reinforced Al (SiC/Al) composites have outstanding advantages in different fields including aerospace. However, the current mechanical and chemical properties of Al–SiC composites are still not up to expectations because of the problems such as wettability, interface reaction, sintering time and SiC size and distribution. Microwave rapid sintering has a promising prospect for the preparation of high performance Al–SiC, however, the lack of process observation leads to the unclear relationship of energy, microstructure and material properties. Therefore microwave rapid sintering of Al–SiC has not been fully explored and applied. In the present paper, the whole process of Al–SiC microstructure evolution was observed accurately by in situ SR-CT experiment during microwave rapid sintering process. Based on the joint analysis of energy-structure-performance, it was found that the spherical SiC located at the neck of Al particles in the microwave field effectively increased the diffusion rate of Al–SiC samples, which inhibited the growth of grains and the densification process was basically completed in a short time. It was revealed that a region with high electric field strength and uniform distribution formed due to SiC with different structural characteristics, thus achieved the rapid densification of the Al–SiC in microwave sintering. The formation and regulation mechanism of rapid densification of Al–SiC during microwave rapid sintering were researched by the relationship between energy-structure and performance, which would provid more understanding for the preparation of high-performance Al–SiC based on microwave rapid sintering technology, and provide the possibility for the preparation of more functional materials. [ABSTRACT FROM AUTHOR]

Dense environmental barrier coatings (EBCs) are urgently needed to protect SiC-based ceramic matrix composites (SiC CMCs) in future gas turbine engines, and multi-component rare-earth (Re) disilicates are attracting attention due to their excellent thermal-mechanical properties and chemical compatibility. In this paper, first-principles calculations were performed on ten different crystal structures and elastic constants of (Re 0.5 Yb 0.5) 2 Si 2 O 7 (Re Sc, Y, Ho, Er, Tm, Yb, Lu) and (Sc x Yb 1-x) 2 Si 2 O 7 (x = 0, 0.25, 0.5, 0.75, 1.00) disilicate materials. Meanwhile, five bulk disilicate ceramics of Yb 2 Si 2 O 7 , (Sc 0.5 Yb 0.5) 2 Si 2 O 7 , (Er 0.5 Yb 0.5) 2 Si 2 O 7 , (Sc 0.33 Er 0.33 Yb 0.34) 2 Si 2 O 7 , and (Sc 0.25 Ho 0.25 Er 0.25 Yb 0.25) 2 Si 2 O 7 were prepared and tested for thermal-mechanical properties. The prepared bulk ceramics exhibit superior thermal stability at 1823 K, with no phase transformation or grain coarsening occurring. Compared to Yb 2 Si 2 O 7 , (Sc 0.5 Yb 0.5) 2 Si 2 O 7 exhibits a smaller unit cell volume, average Re–O bond length, grain size, and thermal conductivity. It also shows increased ion mass disorder, lattice distortion, ion radius disorder, coefficient of thermal expansion (CTE), microhardness, and Young's modulus. However, (Er 0.5 Yb 0.5) 2 Si 2 O 7 mainly exhibits opposite behaviors. Most of the thermal-mechanical properties of (Sc 0.33 Er 0.33 Yb 0.34) 2 Si 2 O 7 and (Sc 0.25 Ho 0.25 Er 0.25 Yb 0.25) 2 Si 2 O 7 are intermediate between those of (Sc 0.5 Yb 0.5) 2 Si 2 O 7 and (Er 0.5 Yb 0.5) 2 Si 2 O 7. These findings of this study may accelerate the development of medium-entropy or high-entropy disilicates with controlled polymorphic phases and customized thermal-mechanical properties. [ABSTRACT FROM AUTHOR]

Due to the unstable chemical properties and poor water solubility of carotenoids, their processing adaptation and oral bioavailability are poor, limiting their application in hydrophilic food systems. Lipid-biomacromolecular compounds can be excellent carriers for carotenoid delivery by taking full advantage of the solubilization of lipids to non-polar nutrients and the water dispersion and gastrointestinal controlled release properties of biomacromolecules. This paper reviewed the research progress of lipid-biomacromolecular compounds as encapsulation and delivery carriers of carotenoids and summarized the material selection and preparation methods for biomacromolecular compounds. By considering the interaction between the two, this paper briefly discussed the effect of these compounds on carotenoid water solubility, stability, and bioavailability, emphasizing their delivery effect on carotenoids. Finally, various challenges and future trends of lipid-biomacromolecular compounds as carotenoid delivery carriers were discussed, providing new insight into efficient loading and delivery of carotenoids. [ABSTRACT FROM AUTHOR]

Bimetallic oxide catalysts derived from zeolitic imidazolate frameworks (ZIFs) have good catalytic oxidation activity, but their application is limited because the powder is not conducive to industrial production. In this study, CoCeOx/cordierite monolithic catalysts derived from ZIFs were prepared by a simple impregnation method. Firstly, a phase transition of Co‐ZIF was induced in ethanol solution by adding excessive Ce(NO3)3. Subsequently, tannic acid (TA) was used to chelate excess metal on the surface to expose more active sites. Meanwhile, TA staying on the surface of the precursor could also prevent the accumulation of Ce at high temperatures. After the activity test, CoCeOx/cordierite showed excellent activity for the catalytic oxidation of o‐xylene with a T90 of 295 °C. The mechanical stability of the catalyst was also tested by ultrasonic vibration method. In addition, we investigated the influence of factors such as impregnation cycles and TA treatment time on the physical and chemical properties. This paper provides a new idea for preparing monolithic catalysts derived from ZIFs. [ABSTRACT FROM AUTHOR]

Controlled modulation of electronic and magnetic properties in stimuli‐responsive materials provides valuable insights for the design of magnetoelectric or multiferroic devices. This paper demonstrates the modulation of electrical and magnetic properties of a semiconductive, paramagnetic metal−organic framework (MOF) Cu3(C6O6)2 with small gaseous molecules, NH3, H2S, and NO. This study merges chemiresistive and magnetic tests to reveal that the MOF undergoes simultaneous changes in electrical conductance and magnetization that are uniquely modulated by each gas. The features of response, including direction, magnitude, and kinetics, are modulated by the physicochemical properties of the gaseous molecules. This study advances the design of multifunctional materials capable of undergoing simultaneous changes in electrical and magnetic properties in response to chemical stimuli. [ABSTRACT FROM AUTHOR]

Controlled modulation of electronic and magnetic properties in stimuli‐responsive materials provides valuable insights for the design of magnetoelectric or multiferroic devices. This paper demonstrates the modulation of electrical and magnetic properties of a semiconductive, paramagnetic metal−organic framework (MOF) Cu3(C6O6)2 with small gaseous molecules, NH3, H2S, and NO. This study merges chemiresistive and magnetic tests to reveal that the MOF undergoes simultaneous changes in electrical conductance and magnetization that are uniquely modulated by each gas. The features of response, including direction, magnitude, and kinetics, are modulated by the physicochemical properties of the gaseous molecules. This study advances the design of multifunctional materials capable of undergoing simultaneous changes in electrical and magnetic properties in response to chemical stimuli. [ABSTRACT FROM AUTHOR]

The realization of efficient and accurate detection of biomolecules has become a key scientific issue in the field of life sciences. With the rapid development of nanotechnology, electrochemical sensors constructed from the superior physical and chemical properties of nanomaterials show faster and more accurate detection. Among nanomaterials, two-dimensional conductive MOF (2D cMOF) is considered to be a star material in electrochemical sensors due to its remarkable conductivity, high porosity, and stability. In this paper, a Cu3(HHTP)2/SPE electrochemical sensor for the detection of ascorbic acid (AA) was constructed by modifying 2D cMOF (Cu3(HHTP)2) on the surface of the screen-printed electrode (SPE). The sensor exhibited excellent catalytic activity in the detection of AA, with a lower detection limit of 2.4 μmol/L (S/N = 3) and a wide linear range of 25–1645 μmol/L. This high catalytic activity can be attributed to the abundant catalytic sites in Cu3(HHTP)2 and the rapid electron transfer between Cu+ and Cu2+, which accelerates the oxidation of AA. This work lays a foundation for the subsequent development of MOFs with special electrochemical catalytic properties and the integration of 2D cMOF into intelligent electrical analysis devices. [ABSTRACT FROM AUTHOR]

This contribution provides a thorough examination of the structural characteristics of pyrochlore-type lanthanide titanates and zirconates Ln2Ti2O7 and Ln2Zr2O7, across various length scales. This paper also examines their processing, interesting physical properties (electrical, magnetic, and thermal characteristics), and responses to high pressure and ion irradiation. Brief sections on the elemental oxides' crystal chemistry, pertinent phase diagrams, and energetics of defect formation are also provided. Pyrochlore-type Ln2Ti2O7 and Ln2Zr2O7 stand out as truly multifunctional materials. Moreover, they have emerged as fascinating materials due to magnetic geometrical frustration, arising from the ordering of magnetic Ln3+ and non-magnetic Ti4+ (or Zr4+) cations into separate, interpenetrating lattices of corner-sharing tetrahedra. This results in a diverse array of exotic magnetic ground states, such as spin-ice (e.g., Dy2Ti2O7 or Ho2Ti2O7) or quantum spin ice (e.g., Tb2Ti2O7), observed at both low and room temperatures. They also exhibit varied electrical and electrochemical characteristics. Some members such as Gd2Zr2O7, function as fast ion conductors with a conductivity (σ) of ≈10−2 S·cm−1 at 800 °C and activation energy (Ea) ranging from 0.85 to 1.52 eV, depending on the degree of structural disorder. Others, such as Gd2TiMoO7, are mixed ionic-electronic conductors with σ ≈ 25 S·cm−1 at 1000 °C, making them promising candidate materials for applications in energy conversion and storage devices and oxygen separation membranes. Their exceptionally low thermal conductivity (e.g., κ ∼ 1.1–1.7 W·m−1·K−1 between 700 and 1200 °C for Ln2Zr2O7), close to the glass-like lower limit of highly disordered solids, positions them as valuable materials for thermal barrier coatings. They can also effectively accommodate actinides (e.g., Pu, Np, Cm, Am) in solid solutions and sustain prolonged exposure to radiation due to alpha-decay events, while preserving the integrity of the periodic atomic structure. Proposed as major components in actinide-bearing ceramics, they contribute to the long-term immobilization and disposal of long-lived waste radionuclides from nuclear programs. Some of these properties are displayed simultaneously, opening avenues for new applications. Despite the wealth of data available in the literature, this review highlights the need for a better understanding of order/disorder processes in pyrochlore-type materials and the influence of the structural length scale on their physical and chemical properties. Recent experimental evidence has revealed that pyrochlore short-range structure is far more complex than originally thought. Moreover, pyrochlore local structure is now believed to include short-range, lower symmetry, ordered domains, such as the orthorhombic weberite-type of structure. Notably, short- and long-range structures appear decoupled across different length scales and temperature regimes, and these differences persist even in well-ordered samples. We believe that the pyrochlore structure offers a unique opportunity for examining the interplay between chemical composition, defect chemistry, and properties. [ABSTRACT FROM AUTHOR]

A variety of graphical invariants have been described and tested, offering lots of applications in the fields of nanochemistry, computational networks, and different scientific research areas. One commonly studied group of invariants is the topological index, which allows research on the chemical, biological, and physical properties of a chemical structure. Topological indices are numerical quantities that can be used to describe the properties of the molecular graph. In this article, we draw from the analytically closed formulas of molecular structures of polycyclic aromatic hydrocarbons by calculating temperature-based topological indices. Our results in this paper may be useful to better understand many physical and chemical properties of polycyclic aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

• We proposed a novel computational method for detect RNA m6A sites. • The proposed method is of powerful ability to predict RNA m6A sites in multiple species or tissues, and of across species or tissue ability. • A user-friendly webserver facilitates recognition of RNA m6A for biologists. N6-methyladenosine (m6A) is the most prevalent, abundant, and conserved internal modification in the eukaryotic messenger RNA (mRNAs) and plays a crucial role in the cellular process. Although more than ten methods were developed for m6A detection over the past decades, there were rooms left to improve the predictive accuracy and the efficiency. In this paper, we proposed an improved method for predicting m6A modification sites, which was based on bi-directional gated recurrent unit (Bi-GRU) and convolutional neural networks (CNN), called Deepm6A-MT. The Deepm6A-MT has two input channels. One is to use an embedding layer followed by the Bi-GRU and then by the CNN, and another is to use one-hot encoding, dinucleotide one-hot encoding, and nucleotide chemical property codes. We trained and evaluated the Deepm6A-MT both by the 5-fold cross-validation and the independent test. The empirical tests showed that the Deepm6A-MT achieved the state of the art performance. In addition, we also conducted the cross-species and the cross-tissues tests to further verify the Deepm6A-MT for effectiveness and efficiency. Finally, for the convenience of academic research, we deployed the Deepm6A-MT to the web server, which is accessed at the URL http://www.biolscience.cn/Deepm6A-MT/. [ABSTRACT FROM AUTHOR]

Certain properties of an object only emerge when a sufficient number of those objects are present in a definite arrangement. For example, one or two water molecules cannot said to be in a liquid state, but a drop of water can be. This concept of emergence has been studied extensively, but only occasionally discussed explicitly in the context of chemistry. In this paper, we aim to show the fruitfulness of the concept of emergence for chemical inquiry by considering four case studies of emergent chemical properties, i. e., the liquidity and freezing of water, structural properties of crystals, thermodynamical phase transitions and quantum mechanical phenomena. We show that some of these properties emerge gradually, some at discrete points, and some should be taken to emerge only when the number of constituents tends to infinity. We argue that studying the way in which chemical properties emerge presents a useful avenue for research that promises greater insight into the nature of those properties. [ABSTRACT FROM AUTHOR]

Triazine pesticides can easily remain in the environment and food, causing serious harm to organisms. Developing a pretreatment technology with strong purification and enrichment capabilities is of great significance for the detection of triazine. In this paper, magnetic dual-template nanomolecular imprinted polymers (MMIPs) were synthesized using silica-modified Fe3O4 magnetic shell nanoparticles as carriers, methacrylic acid (MAA) as a functional monomer, and cyromazine and melamine as template molecules. This material was characterized by transmission electron microscope (TEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The adsorption experiments were carried out and the results showed that the MMIPs had the chemical properties of surface molecular imprinting. The binding constants of MMIPs were 26.95 mg/L and 657.89 mg/L, and their maximum apparent binding capacity was 2.02 mg/g and 8.59 mg/g, respectively. The prepared MMIPs were used as adsorbents for dispersive solid phase extraction, and high-performance liquid chromatography analysis was coupled to determine triazine pesticides from three samples. The recovery of this method was between 84.8% and 109.5% and the limits of detection were between 0.01–0.03 µg/L. This method greatly shortens the sample pretreatment time and achieves the purpose of rapid pretreatment. [ABSTRACT FROM AUTHOR]

The Wiener index is one of the most classic and widely used indicators in topology. It reflects the average distance of any node pair in the graph. It not only makes the boundaries of given graphs clearer but also continuously generates topological indices that are more suitable for new fields, such as the Gutman index. The Wiener index and Gutman index are two important topological indices, which are commonly used to describe the characteristics of molecular structure. They are closely related to the physical and chemical properties of molecular compounds. And they are widely used to predict the physical and chemical properties and biological activity of molecular compounds. In this paper, we study the vertex Gutman index and Gutman index and describe the structural characteristics of all cases of two simple cycles intersecting. We comprehensively analyze the Gutman index and vertex Gutman index in these cases in detail by means of classification discussion and analogical reasoning and characterize their maximum and minimum accordingly. [ABSTRACT FROM AUTHOR]

Plasma gas phase synthesis of graphene method is one-step synthesis, without catalyst, acid, solvent and substrate materials. In this paper, plasma pyrolysis of C2H4 for the preparation of graphene was carried out to investigate the effect of doping H2, CO2, and N2 on the morphology characteristics and chemical reaction properties of the synthesized products at different reaction temperatures ranging from 1500 to 4500 K. It was found that an increase in temperature leads to flatter morphology, less agglomeration, and a decrease in defect density and oxygen content in graphene. The addition of H2, CO2, and N2 gases affected the morphology and defect density of the products. In addition, the high temperature conditions increase the hydrogen atom concentration and etch the edges of graphene, while CO2 slows down the etching process and decreases the defect density. Doping with high enthalpy N2 favors the improvement of crystallinity and defect density at low temperatures, but increases the defect density at high temperatures. These findings contribute to further understanding of the application and optimization of the method of plasma gas phase synthesis of graphene. [ABSTRACT FROM AUTHOR]

Organic farming is system with a growing interest worldwide. The objective of this paper was an assessment of the after-effects of perennial cultivation of spring barley, oats, and red clover in both conventional and organic systems on the chemical properties, enzymatic activity, and potential biochemical soil fertility index of the soil. The study analyzed the activity of acid phosphatase, alkaline phosphatase, urease and dehydrogenases as well as the potential biochemical soil fertility index of soil and the chemical parameters of soil. Soil material was collected from spring wheat grown after spring barley, oats and red clover, occurring in conventional or organic systems in 2009-2019. It has been shown that, compared to a conventional system, the perennial cultivation of red clover and cereals in the organic farming system has contributed to a significant improvement in the chemical (pHKCl by an average of 8%, total organic carbon - 18%, total nitrogen - 15%, N-NH4+ - 34%) and enzymatic (acid phosphatase - 29%, alkaline phosphatase - 67%, urease - 28% and dehydrogenases - 25%) soil quality indicators. The potential biochemical soil fertility index values were also significantly higher in soils in the organic farming system (by an average of 39%). [ABSTRACT FROM AUTHOR]

Background: Agricultural practice is considered as main factor affecting land degradation in several regions in Vietnam. However, there are limited studies relating to degraded soil properties and their soil fertility. This paper aimed to evaluate the degradation of agricultural soil under different land management practices. Methods: A total of 80 samples at 0-10 cm of agricultural soil were collected to analyze selected physicochemical properties. The group of degradation soil properties was classified based on their soil fertility using principal component analysis. Result: The results showed that physicochemical properties in agricultural soil along coastal regions were relatively lower than in hilly regions/secondary forests. High ratio of C:N in agricultural soil was because of degradation. The organic matter, nitrogen and phosphorous contents were low in the soil in lowland areas indicating a high level of degradation (1.43%, 0.09% and 0,04%, respectively). The samples classified into four groups (G1, G2, G3, G4) using principal component analysis indicated differences in soil properties due to degradation. Insufficient and excessive application of inorganic fertilizer could be a further reason affecting the status of soil properties. Overall, soil physicochemical properties indicated poor conditions for agriculture systems, thereby, careful soil management is the primary solution. [ABSTRACT FROM AUTHOR]

The work carried out a physicochemical analysis of porous carbon material (PCM) obtained from brown coal from the Maikuben basin (Kazakhstan). PUM was obtained by carbonization and activation in argon and water vapor. The electrophysical characteristics of the PCM were determined by measuring the electrical capacitance of the samples in the temperature range 293−483 K. The resulting product exhibits high characteristics, including high dielectric permittivity, specific surface area, and capacity, making it effective for use in supercapacitors as an electrode material and for hydrogen storage. The coal carbonization process includes an initial low-temperature (at 180°C, with a heating rate of 10°C/min) treatment of the raw material in the presence of air for 1 hour, followed by carbonization in an inert atmosphere at temperatures ranging from 180-900°C with a heating rate of 5°C/min, and steam activation at the maximum temperature for 1 hour of the coal ground to a 0.1 mm fraction. The material is then extruded into cylindrical shapes (diameter: 2-3 mm, length: 5-10 mm) using a binder material: starch - 5%, sodium hydroxide - 0.5%, water - 17% of the total mass of coal. [ABSTRACT FROM AUTHOR]

In order to evaluate the physical and chemical properties of polymer surfactants and analyze their oil displacement mechanisms, three types of poly-surfactant used in the Daqing oil field were chosen to be researched, and the oil displacement effects were studied using poly-surfactants of different viscosity, dehydrating rate, and core permeability. The main purpose is to determine the reasonable range of different characteristic indexes of polymeric surfactant flooding. The oil displacement effect of 15 cores was analyzed, and the effects of viscosity, the dehydrating rate of emulsion, and permeability on EOR (Enhanced Oil Recovery) were analyzed. The oil displacement mechanisms of polymeric surfactants were researched using a photolithographic glass core. This paper explores the mechanism underlying production enhancement as an EOR target, while simultaneously conducting laboratory tests to assess the physical and chemical properties of polymeric surfactants. The poly-surfactant agents exhibit a notable increase in viscosity, with the optimal displacement effect observed at a core effective permeability exceeding 400 mD, resulting in a potential EOR of 15% or higher. Moreover, at a viscosity ranging between 40 and 70 mPa·s, the total EOR can reach 73%, with the peak efficiency occurring at a viscosity of 60 mPa·s. The water loss rate of the emulsion, ranging between 30% and 70%, achieves optimal performance at 50%. The poly-surfactants' higher viscosity extends the oil sweep area, enhancing recovery efficiency, and noticeably reducing residual oil compared to water flooding. During poly-surfactant flooding, a substantial amount of residual oil is extracted and transformed into droplets. The rapid emulsification of the polymeric surfactant solution with crude oil forms a stable emulsion, contributing to its significant oil recovery effect. This research provides valuable technical support for EOR in thin and low-quality reservoirs of onshore multi-layered sandstone reservoirs. [ABSTRACT FROM AUTHOR]

In 2021, Gutman invented a novel degree-based topological index called the Sombor index, inspired by a geometric interpretation of degree-radii of the edges and invited researchers to investigate their mathematical properties and chemical meanings. The Sombor index was reformulated in terms of the edge degree instead of the vertex degree as the original Sombor Index. In this paper, we compute the exact values of a certain class of graphs. Also, some bounds in terms of the order, size, minimum/maximum degrees and other topological indices are obtained. [ABSTRACT FROM AUTHOR]

In this paper, we present the identification of polymorphisms at an early stage, identified by applying non-standard methods such as SAXS. We provide an analytical approach to polymorphism in the quality/purity of an active pharmaceutical ingredient (API), supplied to a generic company by two different suppliers (i.e., manufacturers). Changes in thermodynamic polymorphism firstly become visible in traces in the larger crystal lattices, which are visible on the SAXS spectrum only using the logarithmic scale, as shown in the result figures. Hence, we are here on the trail of the beginning of a new polymorph in nicomorphine, whose crystal waviness at the early stage is visible only in the additional symmetrical peaks identified and calculated using SAXS, while the chemical analyses excluded all kinds of chemical impurities. The chemical and structural properties were studied using the following techniques: SAXS, WAXS, DSC, dissolution, Raman spectroscopy, and FTIR. Only the SAXS technique could identify crucial differences and calculate the additional signals related to giant crystals, whilst a standard method such as WAXS showed none, and nor did the chemical analyses, such as Raman spectroscopy and FT-IR. This means that due to water in crystallization (known in nicomorphine) or thermodynamic waviness, the formation of the new polymorph starts first in traces, which become visible at larger distances from the crystal lattice, detectible only in the SAXS range. This is a very important premise and hypothesis for further research, and we believe that this work lays a new stone in understanding the origin of new unknown polymorphs and their mixtures. Therefore, the aim of this work is to show that the use of non-standard methods (i.e., SAXS) can be of great benefit to API analysis and the identification of polymorphic changes in the early phase, which can cause varied stability, solubility and bioavailability and thus different therapeutic effects or side effects. [ABSTRACT FROM AUTHOR]

Purpose: Tegafur (TF) is one of the most important clinical antitumor drugs with poor water solubility, severely reducing its bioavailability. This work develops new cocrystals to improve the solubility of TF and systematically investigates the intermolecular interactions to provide new insights into the formation of cocrystal and changes in physicochemical properties. Method: In this paper, two new 1:1 cocrystals of TF with 2,4 dihydroxybenzoic acid (2,4HBA) and p-nitrophenol (PNP) were synthesized. The cocrystal products were identified and characterized by various solid state analysis techniques. And the high performance liquid chromatography (HPLC) was conducted to determine the solubility and dissolution rate of TF and cocrystals. Moreover, the quantum chemistry calculations of crystal structure provided theoretical support for the results. Result: Compared with pure TF, the solubility and dissolution rate of TF-2,4HBA is significantly increased in a pH 6.8 buffer at 37°C. Under accelerated storage conditions (40°C, 75% RH), all cocrystal exhibits excellent stability over 8 weeks. Hirshfeld surface (HS) analysis, atoms in molecules (AIM) analysis, interaction region indicator (IRI) analysis, molecular electrostatic potential surface (MEPS) analysis and frontier molecular orbital (HOMO–LUMO) analysis were integrated to understand the hydrogen bonding interaction more comprehensively. The simulation results are in good agreement with the experimental data. The results show that the analysis of physical and chemical properties of TF-PNP cocrystal and TF crystal by quantum chemistry method is reliable at molecular level. Conclusion: These results are helpful to provide guiding methods in the cocrystal development and theoretical study of tegafur. [ABSTRACT FROM AUTHOR]

Rare-earth perovskite oxides have become a research hotspot in the fields of environment and energy owing to their structural tunability, excellent redox properties, high stability and high catalytic activity. Researchers have designed and developed different rare-earth perovskite catalysts for tackling environmental pollutants in recent years. This review summarizes recent research progress on rare-earth perovskite catalysts in the catalytic oxidation and photocatalytic degradation of pollutants, gas sensing of volatile organic compounds and photocatalytic water splitting for hydrogen production and carbon dioxide reduction and conversion, and summarizes the mechanism of these reactions. It also discusses in detail the relationship between structural modification, synthesis process and the physical–chemical properties of the catalysts. Finally, the challenges with rare-earth chalcocite catalysts in the field of environment and energy are discussed. This paper reviews recent progress in rare-earth perovskite oxide materials, explores the effects of capacity factors, lattice defects, different metal active centers and perovskite modifications on crystal structure and applied properties, discusses the effects of synthesis processes (sol-gel, co-precipitation, microemulsion, hydrothermal, high-temperature) on their physical and chemical properties, and summarizes their applications in pollutant catalytic oxidation and photocatalytic degradation, VOCs gas sensing, and photocatalytic splitting of water for hydrogen production and carbon dioxide reduction and conversion. (Image credit: P. Li.) [ABSTRACT FROM AUTHOR]