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Structure determination is necessary to identify unknown organic molecules, such as those in natural products, forensic samples, the interstellar medium, and laboratory syntheses. Rotational spectroscopy enables structure determination by providing accurate 3D information about small organic molecules via their moments of inertia. Using these moments, Kraitchman analysis determines isotopic substitution coordinates, which are the unsigned |x|, |y|, |z| coordinates of all atoms with natural isotopic abundance, including carbon, nitrogen, and oxygen. While unsigned substitution coordinates can verify guesses of structures, the missing +/− signs make it challenging to determine the actual structure from the substitution coordinates alone. To tackle this inverse problem, we develop Kreed (Kraitchman REflection-Equivariant Diffusion), a generative diffusion model that infers a molecule's complete 3D structure from only its molecular formula, moments of inertia, and unsigned substitution coordinates of heavy atoms. Kreed's top-1 predictions identify the correct 3D structure with near-perfect accuracy on large simulated datasets when provided with substitution coordinates of all heavy atoms with natural isotopic abundance. Accuracy decreases as fewer substitution coordinates are provided, but is retained for smaller molecules. On a test set of experimentally measured substitution coordinates gathered from the literature, Kreed predicts the correct all-atom 3D structure in 25 of 33 cases, demonstrating experimental potential for de novo 3D structure determination with rotational spectroscopy. [ABSTRACT FROM AUTHOR]

The absolute photoabsorption cross sections of norbornadiene (NBD) and quadricyclane (QC), two isomers with chemical formula C7H8 that are attracting much interest for solar energy storage applications, have been measured from threshold up to 10.8 eV using the Fourier transform spectrometer at the SOLEIL synchrotron radiation facility. The absorption spectrum of NBD exhibits some sharp structure associated with transitions into Rydberg states, superimposed on several broad bands attributable to valence excitations. Sharp structure, although less pronounced, also appears in the absorption spectrum of QC. Assignments have been proposed for some of the absorption bands using calculated vertical transition energies and oscillator strengths for the electronically excited states of NBD and QC. Natural transition orbitals indicate that some of the electronically excited states in NBD have a mixed Rydberg/valence character, whereas the first ten excited singlet states in QC are all predominantly Rydberg in the vertical region. In NBD, a comparison between the vibrational structure observed in the experimental 11B1–11A1 (3sa1 ← 5b1) band and that predicted by Franck–Condon and Herzberg–Teller modeling has necessitated a revision of the band origin and of the vibrational assignments proposed previously. Similar comparisons have encouraged a revision of the adiabatic first ionization energy of NBD. Simulations of the vibrational structure due to excitation from the 5b2 orbital in QC into 3p and 3d Rydberg states have allowed tentative assignments to be proposed for the complex structure observed in the absorption bands between ∼5.4 and 7.0 eV. [ABSTRACT FROM AUTHOR]

Saponins encompass a diverse group of naturally occurring glycoside molecules exhibiting amphiphilic properties and a broad range of biological activities. There is a resurgence of interest in those saponins produced by marine organisms based on their potential therapeutic benefits, application in food products and most recently their potential involvement in intra- and inter-species chemical communication. The continual advancements in liquid chromatography techniques and mass spectrometry technologies have allowed for greater detection rates, as well as improved isolation and elucidation of saponins. These factors have significantly contributed to the expansion in the catalogue of known saponin structures isolated from marine invertebrates; however, there currently exists no specific chemical library resource to accelerate the discovery process. In this study, a Marine Animal Saponin Database (MASD v1.0) has been developed to serve as a valuable chemical repository for known marine saponin-related data, including chemical formula, molecular mass and biological origin of nearly 1000 secondary metabolites associated with saponins produced by marine invertebrates. We demonstrate its application with an exemplar asteroid extract (Acanthaster cf. solaris, also known as crown-of-thorns starfish; COTS), identifying saponins from the MASD v1.0 that have been previously reported from COTS, as well as 21 saponins isolated from multiple other related asteroid species. This database will help facilitate future research endeavours, aiding researchers in exploring the vast chemical diversity of saponins produced by marine organisms and providing ecological insights, and the realisation of their potential for various applications, including as pharmaceuticals. [ABSTRACT FROM AUTHOR]

The development of highly active cathode is crucial to promote the electrochemical performance of intermediate-temperature solid oxide fuel cells (IT-SOFCs). Here, it is reported the cobalt and/or iron ions as dopants into Ba(Zr, Y)O 3-δ with the nominal chemical formulae of BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BCFZY), BaCo 0.8 Zr 0.1 Y 0.1 O 3-δ (BCZY), and BaFe 0.8 Zr 0.1 Y 0.1 O 3-δ (BFZY), which all form the main cubic perovskites in addition to a small amount of co-assembled hexagonal D-Ba(Co, Fe)O 3-δ , D-BaCoO 3-δ , and D-BaFeO 3-δ under the same preparing condition. Among three samples, BCZY composite shows the highest capacity of O 2 adsorption, lower thermal expansion coefficient (19.1 × 10−6 K−1), and highest electrical conductivity of 2.73 S cm−1 (750 °C). The symmetric cell with BCZY composite cathode exhibits excellent ORR activity with the lowest area specific resistance of 0.10 Ω cm2 at 700 °C, which is 0.71 and 0.67 times those of BCFZY composite and BFZY composite cathodes. Accordingly, the single cell with BCZY composite cathode shows the lowest R P of 0.16 Ω cm2 and the highest peak power density of 2.24 W cm2 at 700 °C. The distribution of relaxation times (DRT) analysis reveals that BCZY composite cathode shows the superior surficial oxygen exchange and charge transfer activity. [ABSTRACT FROM AUTHOR]

Within the current challenges in medicinal chemistry, the creation of novel and improved therapeutic agents stands out. 2‐Cyano‐3‐(thiophen‐2‐yl)prop‐2‐enethioamide (CTPTA) ligand was complexed with palladium (II) and platinum (II) ions within the nanoscale with the molecular formula [M (CTPTA)Cl2]. H2O. The CTPTA ligand and its complexes were characterized by elemental analysis, UV–Vis spectra, FTIR, mass spectra, TGA, magnetic measurement, and the molar conductance technique. Analysis with a scanning electron microscope (SEM) revealed that the nanostructure dimension of both complexes is predominantly between 10 and 30 nm. The CTPTA ligand functions as a bidentate ligand, utilizing thione sulfur, and cyanide nitrogen atoms. Density functional theory was employed to analyze the geometric structure properties of the CTPTA ligand and its complexes. Natural population (NPA) and Mulliken population (MPA) methods were used to calculate the charge distribution. The cytotoxic impact results of all compounds on human liver cancer (HepG2) cell line were satisfactory. The ligand and its complexes were also tested against gram‐negative and gram‐positive bacteria in vitro. The findings of the molecular docking study supported the cytotoxicity and antibacterial effects. The antioxidant and anti‐inflammation activities of synthesized palladium (II) and platinum (II) complexes had a great spectrum of activity. The preclinical pharmacokinetic studies on albino rats revealed that the newly studied complexes achieved excellent antitumor results. This was clear in the investigated parameters, especially the amelioration of AFP levels, liver weight, oxidative stress, and lobular hepatic architecture injury. [ABSTRACT FROM AUTHOR]

Three novel organic–inorganic polyoxoniobate-based compounds modified with Cu(II) amine complexes were synthesized under hydrothermal conditions with the chemical formulas as follows: K0.5[Cu(enMe)2]4[K0.5SiNb12O40(VO)4.25](OH)1.5·9H2O (1), K0.5[Cu(enMe)2]4[K0.5H2PNb12O40(VO)2]·12.5H2O (2), and K0.5[Cu(enMe)2]4[K0.5H2VNb12O40(VO)2]·12.5H2O (3) (enMe = 1,2-diaminopropane). These compounds were characterized by single crystal X-ray diffraction, infrared spectroscopy (IR), UV-Vis spectroscopy, elemental analysis and powder X-ray diffraction (PXRD) analysis. Notably, while these three compounds exhibit identical cell parameters, they possess distinct stoichiometric compositions and differing polyoxometalate building block structures. Typically, compounds with the same cell parameters are classified as isostructural, sharing identical structures with only minor elemental variations in their compositions. To the best of our knowledge, compounds 1–3 represent the first instances of compounds that share the same cell parameters yet are not isostructural. In this study, we not only synthesized these three compounds and thoroughly examined the differences in their structures and properties, but also investigated their catalytic performances as catalysts for the oxidation of styrene. [ABSTRACT FROM AUTHOR]

Fluorinated organic compounds (FOCs) represent a class of synthetic chemicals distinguished by their resilient carbon–fluorine bonds, which demonstrate an ability to withstand environmental degradation over an extended period. The integration of FOCs into cutting-edge applications, including lithium-ion batteries (LiBs), presents considerable potential for environmental harm that has not yet been sufficiently addressed. This study focuses on the environmental fate of two fluorinated aromatics, tris(pentafluorophenyl)borane (TPFPB) and tris(pentafluorophenyl)phosphine (TPFPP), given their important role in improving the performance of LiBs. To achieve this, laboratory simulation methods including total oxidizable precursor assay, electrochemistry (EC), Fenton reaction, UV-C irradiation, and hydrolysis were employed. Liquid chromatography and gas chromatography coupled with high-resolution mass spectrometry were used for identification of transformation products (TPs) and prediction of their molecular formulae. Despite the structural similarity between TPFPB and TPFPP, distinct differences in electrochemical behavior and degradation pathways were observed. TPFPB readily underwent hydroxylation and hydrolysis, resulting in a wide range of 49 TPs. A total of 28 TPs were newly identified, including oligomers and highly toxic dioxins. In contrast, TPFPP degraded exclusively under harsh conditions, requiring the development of innovative conditioning protocols for EC. In total, the simulation experiments yielded nine structurally different compounds, including seven previously undescribed, partially defluorinated TPs. This study highlights the potential risks associated with the use of FOCs in LiBs and provides insight into the complex environmental behavior of FOCs. [ABSTRACT FROM AUTHOR]

With the chemical formula CaCl2, calcium chloride is a salt as well as an inorganic material. At room temperature, it has the consistency of a white, crystalline solid and is very water-soluble. It can be created by neutralizing calcium hydroxide with hydrochloric acid. Calcium chloride is a solution with a large enthalpy change. It is extensively utilized in research facilities, manufacturing facilities, and pharmaceuticals, including all types of food-graded applications, the treatment of acute illnesses, packaging for drying tubes, dust controllers, and de-icing, among other uses. In this paper, firstly we compute the topological indices, coindices, and reverse indices of CaCl2. Further, we employ machine learning strategies to capture the best suitable set of indices for the proximity of the prediction of distinct physio-chemical properties of CaCl2. To strengthen the results, different regression techniques are implemented to predict HOF of CaCl2 based on our features, and the most influential features were detected to verify our results. [ABSTRACT FROM AUTHOR]

ABSTRACT The bowl‐shaped flexible carboxylic acid zwitterion 1,1′,1″‐(2,4,6‐trimethylbenzene‐1,3,5‐triyl)tris (methylene)‐tris(4‐carboxy‐pyridinium)tribromide (H3LBr3) ligand‐based lanthanide metal–organic framework (Ln‐MOF) was synthesized for the first time under solvothermal conditions. Single crystal X‐ray diffraction analysis indicates that the molecular formula of Ln‐MOF is [EuL2(H2O)4Br3]·2H2O (1). Luminescence sensing experiments demonstrate that 1 shows obvious fluorescence quenching for nitrobenzene (NB), Fe3+, and Cr2O72− with low detection limits of 0.118 μM, 9.098 nM, and 17.409 nM, respectively. 1 can be regarded as a luminescence sensor with multiple functions, displaying high selectivity, wonderful antiinterference ability, outstanding sensitivity, and recyclability to detect NB, Fe3+, and Cr2O72−. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the behavior of LiMgN half-Heusler (HH) semiconductor doped by transition metals (TM  =  Mn, Fe, Co and Ni). HHs belong to the F 4 ̄ 3 m space group (No. 216) and have a zinc blende structure that can be described by the chemical symbol XYZ. The research methodology utilized in this investigation involves theoretical analysis based on the principles of density functional theory (DFT). The studied LiMg 0. 9 5 TM 0. 0 5 N alloy displayed the half-metallicity behavior when TM  =  Fe, Co and Ni. Hence, these systems could be a promising candidate in spintronic application thanks to their ferromagnetism. The principal contribution to magnetism in the full LiMg 0. 9 5 TM 0. 0 5 N alloys comes from the Mn, Fe, Co and Ni doping. The partial magnetic moments of these elements are significantly greater than the combined partial magnetic moments of Li, Mg and N. When comparing LiMg 0. 9 5 Mn 0. 0 5 N to LiMg 0. 9 5 Fe 0. 0 5 N, 5Co 0. 0 5 N and LiMg 0. 9 5 Ni 0. 0 5 N, it is important to note that the exchange splitting energy Δ (e + , e −) TM associated to their spin up and spin down were discussed. The variation of Mn(3d) in relation to ( e + , e − ) is larger than that of Fe, Co and Ni. Therefore, Δ (e + , e −) Mn > Δ (e + , e −) Fe > Δ (e + , e −) Co > Δ (e + , e −) Ni . Furthermore, there is a correlation between the magnetic moment and electronegativity trend of the TM dopant. Specially, the electronegativity trend ( χ TM ) is well matched with the total spin moment trend, where χ Ni > χ Co > χ Fe > χ Mn . [ABSTRACT FROM AUTHOR]

In recent years, machine learning (ML) has emerged as a potential tool in the exploration of thermoelectric (TE) materials. This study exploits the StarryData2 public database to construct an ML model for predicting the figure‐of‐merit ZT of TE materials. The original dataset from StarryData2 (372,480 datapoints) underwent systematic cleaning, resulting in a refined dataset of 18,126 instances with 2,761 unique compounds. The cleaned data is employed to train an XGBoost regressor model, utilizing chemical formulas of TE compounds as features to predict ZT at given temperatures. The XGBoost regressor exhibited high prediction accuracy, achieving the coefficient of determination (R2) scores of 0.815 and mean absolute error (MAE) of 0.103 for the test set, further evaluated through cross‐validation across 5 folds. The learning curve analysis demonstrated improved model performance with increased training data. Furthermore, the contributions of different chemical descriptors to ZT are analyzed based on feature importance analysis. Beyond conventional TE families in the training set, the trained model is applied to predict ZT for promising unexplored TE materials and estimate optimal doping concentrations. This comprehensive study shows the impact of ML on TE material research, offering valuable insights and accelerating the discovery of materials with enhanced TE properties. [ABSTRACT FROM AUTHOR]

In cold methanol, energetic ionic liquid 1-n-propyl-3-vinyl-imidazol-1-ium perchlorate, 1, crystallizes in the presence of excess Ba(ClO4)2, 2, into tetrakis 1-propyl-3-vinyl-imidazol-1-ium·barium hexa-perchlorate, 3. Crystals of 3, with molecular formula (C8H13N2)4·BaCl6O24, are colorless and monoclinic, with space group P21/c. The crystal structure is characterized by a dodecahedral coordination around the barium atom, with each perchlorate chelating Ba2+ in a κ2O,O' fashion, and the Ba(ClO4)64− anion is surrounded by four imidazolium cations. [ABSTRACT FROM AUTHOR]

Acenes or polyacenes are a group of organic compounds and polycyclic aromatic hydrocarbons consisting of benzene ( C 6 H 6) rings that are linearly fused. They are also the building blocks of nanotubes and graphene and follow the general molecular formula C 4 n + 2 H 2 n + 4 . Due to the applications of polyacenes in optoelectronics, they are interesting for chemical and electrical engineering researchers. In this article, the general formulas for distance-based topological indices of Szeged, Mostar, and Padmakar-Ivan are determined by SMP-polynomials, which do not require edge counting and this formula work only by having the number of benzene rings in the composition of polyacenes. [ABSTRACT FROM AUTHOR]

The structures of two K-richterite crystals with the crystal chemical formulas (K0.44Na0.320.24)Σ=1(Ca1.18Na0.82)Σ=2Mg5Si8O22OH2 and (K0.83Na0.020.15)Σ=1(Ca1.11Na0.89)Σ=2Mg5Si8O22OH2 synthesized at a pressure of 3 GPa and a temperature of 1000°С in the MgSiO3 + CaMgSi2O6 + K2CO3 + Na2CO3 + CO2 + H2O system were studied by single-crystal X-ray analysis and Raman spectroscopy. The monoclinic cell parameters were obtained: a = 10.0256(5) and 9.9748(11) Å, b = 17.9874(7) and 17.9879(16) Å, c = 5.2687(3) and 5.2746(6) Å, Ve.c. = 916.17(18) and 918.52(8) Å3, β = 104.520(12)° and 104.821(5)°, sp. gr. С2/m (12), and Z = 2. The sites M(1), M(2), and M(3) are inhabited by Mg2+, while site M(4) is occupied simultaneously by Ca2+ and Na+. The Na+ cations not included in M(4) are located in position A, which also accommodates K+ cations. Raman spectroscopy made it possible to reveal vacancies in position A in both samples. The structure corresponds to the "ideal" structure of richterite group minerals. The unit cell volume of the measured crystals is directly proportional to the K content in position A. Based on the generalization of new and published data, an equation of the dependence of Vu.c. for amphiboles of the richterite Na(NaCa)Mg5Si8O22(OH)2–K-richterite K(NaCa)Mg5Si8O22(OH)2 series with a low tremolite component on the K content in position A is proposed. [ABSTRACT FROM AUTHOR]

The electrochemical performance of gold electrode in sulfuric acid was studied with addition of different concentrations of dissolved fullerenol-d with C60(OH)24 chemical formula. Based on the cyclic voltammetry data, the conclusion of surface complexation of Au(III) with fullerenol was made. The scheme was suggested to describe the electrode process, based on catalysis of anodic Au dissolution by fullerenol molecules. The technique was suggested to detect fullerenol-d (C60(OH)24) in concentration range from 2.6·10–9 M to 2.0·10–7 M by means of cyclic voltammetry of gold in aqueous sulfuric acid solution. [ABSTRACT FROM AUTHOR]

The current investigation involved the synthesis and detailed characterization of novel mixed‐ligand complexes of Mn(II) (MnDPPNPH) and Cu(II) (CuDPPNPH). These complexes incorporate 2,6‐di(1H‐pyrazol‐1‐yl)pyridine (DPP) and a Schiff base derived from 2‐hydroxy naphthaldehyde (NPH). The synthesized complexes revealed a stoichiometric ratio of 1:1:1 (metal:DPP:NPH), indicative of an octahedral coordination geometry around the Mn(II) and Cu(II) centers, as represented by the chemical formula [M (DPP)(NPH)(Cl)]. To elucidate their structural and electronic properties, theoretical calculations were performed. These calculations facilitated the optimization of the geometrical structures and provided insights into the molecular orbital characteristics of the complexes. The MnDPPNPH and CuDPPNPH complexes demonstrated potential phenoxazinone synthase mimicking activity by catalyzing aerial coupling of o‐aminophenol (OAPh) to form phenoxazine‐2‐one (phenox). The mimicking activity of these complexes was quantitatively assessed using Michaelis–Menten enzymatic kinetics. Various enzyme kinetics plots were employed to determine several kinetic parameters, including the specificity constant and turnover number (kcat), which are crucial for understanding the efficiency of the catalytic cycles. Remarkably, the synthesized MnDPPNPH and CuDPPNPH complexes exhibited significantly higher turnover numbers (kcat) compared to previously reported complexes. This finding suggests that these new complexes possess superior catalytic activity, highlighting their potential as effective catalysts for reactions mimicking the function of phenoxazinone synthase. [ABSTRACT FROM AUTHOR]

Finding appropriate photocatalysts for solar‐driven water (H2O) splitting to generate hydrogen (H2) fuel is a challenging task, particularly when guided by conventional trial‐and‐error experimental methods. Here, density functional theory (DFT) is used to explore the MXenes photocatalytic properties, an emerging family of two‐dimensional (2D) transition metal carbides and nitrides with chemical formula Mn+1XnTx, known to be semiconductors when having Tx terminations. More than 4,000 MXene structures have been screened, considering different compositional (M, X, Tx, and n) and structural (stacking and termination position) factors, to find suitable MXenes with a bandgap in the visible region and band edges that align with the water‐splitting half‐reaction potentials. Results from bandgap analysis show how, in general, MXenes with n = 1 and transition metals from group III present the most cases with bandgap and promising sizes, with C‐MXenes being superior to N‐MXenes. From band alignment calculations of candidate systems with a bandgap larger than 1.23 eV, the minimum required for a water‐splitting process, Sc2CT2, Y2CT2 (Tx = Cl, Br, S, and Se) and Y2CI2 are highlighted as adequate photocatalysts. [ABSTRACT FROM AUTHOR]

Semiconductors, with their exceptional properties, have diverse applications across fields such as photovoltaics, sensing, and catalysis. In the present study, nickel pyro-vanadate compounds of high purity and homogeneity, with the chemical formula A2NiV2O7 (where A = Na, Ag), were synthesized under precisely controlled stoichiometric conditions. The primary focus is to investigate the optical and electronic properties of these compounds using a combination of experimental techniques and theoretical modeling. Initially, insights into the chemical structure and morphology of the synthesized semiconductor were obtained through powder x-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). A2NiV2O7 were found to be homogeneous, crystalline in nature, and isotypic with Κ2CoV2O7, exhibiting alternating layers of NiV2O7 and Ag/Na. Moreover, absorption spectra obtained from UV–Vis diffuse reflectance spectroscopy (DRS) showed direct optical bandgaps of 1.83 eV for Na2NiV2O7 and 1.92 eV for Ag2NiV2O7, affirming their semiconductor properties. Further characterization was performed using density functional theory (DFT) and hybrid-DFT methods. These advanced techniques provide detailed understanding of the electronic structure and properties across different sodium–silver ratios. The computed electronic structures demonstrate the separation of the conduction band (CB) and valence band (VB) around the Fermi level, with bandgaps of 0.44 eV and 1.76 eV for Na2NiV2O7, and 0.56 eV and 1.60 eV for Ag2NiV2O7, as determined using the Perdew–Burke–Ernzerhof (PBE) and DFT+U methods, respectively. This comprehensive investigation offers valuable insights into the optical and electronic dynamics of nickel pyro-vanadate compounds, establishing a foundation for their potential applications in various fields, including optoelectronics, photocatalysis, and energy storage. [ABSTRACT FROM AUTHOR]

The air-sea CO2 flux in the coastal ocean is a key component of the global carbon budget. However, due to the scarcity of data, the many sources and sinks of carbon and their complex interactions in these waters remain poorly understood. In 2021, the Tara schooner collected 14,000 km of CO2 fugacity (fCO2) measurements along the coast of South America, including in the Amazon River-Ocean continuum (https://doi.org/10.5281/zenodo.13790065 , Olivier et al., 2024a). The interactions between the Amazon River and its oceanic plume are complex, and under a combined influence of many processes such as tides and bathymetry. Downstream of the Amazon River plume, the fCO2 is low compared with that of the atmosphere, reaching a minimum of 42 μatm. In the river, fCO2 reaches up to 3000 μatm. South of the estuary, the waters of the North Brazil Current have a fCO2 exceeding 400 μatm. Along the Brazil Current, fCO2 is around 400 μatm and decreases, as does temperature, as the schooner sails away from the equator. Nevertheless, in all the data collected in this coastal environment, salinity varies greatly, and therefore describes best the variability of fCO2. Despite the strong variability and uncertainties in the data, comparison with discrete samples of other carbonate parameters shows that the mean differences (2 µatm) are within the range of uncertainties related to the chemical formula used for the comparison. This data set helps to fill the gap in our knowledge of the behavior of fCO2 in the under-sampled region of the Brazilian coast. [ABSTRACT FROM AUTHOR]

A d10 Cu(I) two‐dimensional (2D) metal–organic framework (MOF) with chemical formulas, {[Cd(L)(tcm)(H2O)]⋅2H2O}n (1) (L = 1,3,5‐tris(4‐pyridylethynyl)benzene; tcm−1 = tricyanomethanide) was synthesized and structurally characterized by single crystal X‐ray diffraction method. In 1, the coordination geometry of Cu(I) ion is distorted tetrahedral coordinated to four N atoms from three L and one tcm− ligands. A 2D puckered honeycomb‐like layer is formed via the bridges of Cu(I) ions and L ligands with tris‐monodentate coordination mode. Two 2D layers are mutually interpenetrated via the π–π stacking interaction between benzene ring of L ligand and pyridyl ring of neighboring L ligand to form a two‐fold interpenetrated 2D net and then arranged orderly to construct its 3D supramolecular network. Thermal stability and in‐situ temperature‐dependent structural variations of 1 are performed by TG analysis associated with temperature‐dependent PXRD measurement. The water vapor ad‐/de‐sorption isotherm and CO2 adsorption isotherm of 1 are measured and discussed. [ABSTRACT FROM AUTHOR]

Rationale: High‐resolution mass spectrometry (HRMS) combined with electrospray ionization (ESI) has been the most useful technique for molecular characterization of dissolved organic matter (DOM) derived from diverse sources. However, the comprehensive detection of DOM composition was hindered by ionization suppression observed in ESI sources. HRMS coupled with liquid chromatography (LC) is a potential tool for comprehensive molecular characterization of DOM. Methods: The Suwannee River fulvic acids (SRFAs) and two DOM samples from seawater and refinery wastewater extracted by solid phase extraction (SPE) were analyzed by LC‐Orbitrap MS coupled with ESI. The mobile phases, solvent composition, and gradient in the LC‐Orbitrap MS analysis were optimized. Results: The number of detected molecular formulae of SRFAs by online LC‐Orbitrap MS was significantly increased by approximately 40% compared to direct injection. These additional detected compounds are mainly protein and lignin‐like compounds, with a low O/C ratio and high H/C ratio. For the SRFAs, the relative standard deviations (%) of reproducibility are 5.51, 2.33, 7.97, and 1.80 for average O/C, H/C, double bond equivalent, and modified aromaticity index, respectively. Conclusions: This study proposed a simple and rapid method based on LC‐Orbitrap MS for an in‐depth analysis of the molecular composition of DOM, achieving a remarkable analysis time of only 5 min per sample. The rapid method provides a dependable and efficient approach for the molecular characterization of DOM, thereby advancing our comprehension and investigation of DOM across diverse ecosystems. [ABSTRACT FROM AUTHOR]

To investigate the combustion characteristics of non-stick coal and the formation patterns of main combustion products and radicals, this study initially conducted a TG-DSC experiment of non-stick coal. Subsequently, non-stick coal was characterized and analyzed using XPS and 13C NMR experiments, and a molecular model with the formula C208H199O23N3S was constructed. Subsequently, the ReaxFF MD method was employed to simulate the combustion molecular dynamics of the non-stick coal periodic mixing model under varying oxygen content and temperature conditions. The analysis focused on elucidating the formation patterns of free and primary products during combustion. Experimental findings indicate that the combustion of non-stick coal progresses through stages, including water evaporation and desorption (30–145.65 °C), dynamic equilibrium (145.65–181.76 °C), oxygen weight gain (181.76–263.56 °C), thermal decomposition (263.56–379.14 °C), combustion (379.14–562.04 °C) and burnout (562.04–800 °C). The ignition temperature of non-stick coal was determined to be 379.14 °C. The simulation results indicate that an increase in temperature and oxygen content further enhances the relatively stable peak production of CO2. The peak increase of CO production is weaker than that of CO2. The rise in temperature also promotes the formation of H2O, while the increase in oxygen content initially enhances and subsequently inhibits the peak production of H2O. H radicals, O radicals, and OH radicals are primarily generated through the decomposition reactions of small molecular compounds or other free radicals. Free radical polymerization and the decomposition of small molecular compounds represent the primary pathways for the formation of CO, CO2, and H2O. [ABSTRACT FROM AUTHOR]

Holmium based metal–organic frameworks (MOFs) are attractive due to their potential biomedical and radiotherapeutic applications. Two new three-dimensional MOFs consisting of holmium(III) and 3,3′,5,5′-azobenzenetetracarboxylate (H4abtc) were prepared. The microporous Ho(III) binuclear MOF (Ho2-abtc) with the chemical formula of [Ho2(abtc)1.5(DMF)4]·DMF exhibited a three-dimensional framework. A hexacluster (RE6X8) based three-dimensional MOF with the chemical formula ([Ho6(abtc)3(μ3-X)8]·DMA; X = OH−/F−, DMA = dimethyl ammonium) exhibited Ho6 clusters bridged by OH−/F− ions. The presence of hexaclusters in the holmium MOFs opens up the design of new MOFs for the holmium delivery with high holmium content. The crystal structures of the MOFs were solved. These MOFs are characterized by single-crystal X-ray diffraction (SC-XRD), powder XRD, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), 19F nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), gas adsorption analysis, and X-ray photoelectron spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

Samples of germanium borosilicate glasses with chemical formula 50.5B2O3 + 0.5CeO2 + 10SiO2 + (20‐x) CaO + 19Na2O + XGeO2 with 0 (GeO0) ≤ X ≤ 5 (GeO5) mol% were fabricated by using the melt quenching technique. Structure, physical, and optical properties as well as radiation attenuation capacity was examined. XRD data confirmed that GeOX samples were in amorphous state. The density (ρ) of the prepared glass samples increased from 2.24 to 2.55 g/cm3, while the molar volume (Vm) slightly declined from 26.8 to 26.42 cm3/mol. The UV absorption edge shifted to a higher wavelength as the concentration of GeO2 increased. The values of direct band gap (EgDirect)$(\bm{E_g^{Direct}})$ ranged from 3.36 to 2.91 eV, and the indirect (EgIndirect)$(\bm{E_g^{Indirect}})$ ranged from 3.12 to 2.75 eV. Urbach energy (Eu) values fluctuated between 0.65 to 0.16 eV. As the Ge4+ ion increased, the glass sample's refractive index enhanced. Mass attenuation coefficients (MACs) of GeOX samples increased from 6.788 to 10.381 cm2/g at 0.015 MeV. The GeO5 sample possessed the lowest half value layer (HVL) and mean free path (MFP). Effective atomic number (Zeff) of GeOX possessed the same trend of MAC. Results confirmed that the suggested GeOX glasses can be applied in different optical and radiation attenuation applications. [ABSTRACT FROM AUTHOR]

Samples of germanium borosilicate glasses with chemical formula 50.5B2O3 + 0.5CeO2 + 10SiO2 + (20‐x) CaO + 19Na2O + XGeO2 with 0 (GeO0) ≤ X ≤ 5 (GeO5) mol% were fabricated by using the melt quenching technique. Structure, physical, and optical properties as well as radiation attenuation capacity was examined. XRD data confirmed that GeOX samples were in amorphous state. The density (ρ) of the prepared glass samples increased from 2.24 to 2.55 g/cm3, while the molar volume (Vm) slightly declined from 26.8 to 26.42 cm3/mol. The UV absorption edge shifted to a higher wavelength as the concentration of GeO2 increased. The values of direct band gap (EgDirect)$(\bm{E_g^{Direct}})$ ranged from 3.36 to 2.91 eV, and the indirect (EgIndirect)$(\bm{E_g^{Indirect}})$ ranged from 3.12 to 2.75 eV. Urbach energy (Eu) values fluctuated between 0.65 to 0.16 eV. As the Ge4+ ion increased, the glass sample's refractive index enhanced. Mass attenuation coefficients (MACs) of GeOX samples increased from 6.788 to 10.381 cm2/g at 0.015 MeV. The GeO5 sample possessed the lowest half value layer (HVL) and mean free path (MFP). Effective atomic number (Zeff) of GeOX possessed the same trend of MAC. Results confirmed that the suggested GeOX glasses can be applied in different optical and radiation attenuation applications. [ABSTRACT FROM AUTHOR]

Two-dimensional materials with chemical formula MA2Z4 are a promising class of materials for optoelectronic applications. To exploit their potential, their stability with respect to air pollution has to be analyzed under different conditions. In a first-principle study based on density functional theory, we investigate the adsorption of three common environmental gas molecules (O2, H2O, and CO2) on monolayer WSi2N4, an established representative of the MA2Z4 family. The computed adsorption energies, charge transfer, and projected density of states of the polluted monolayer indicate a relatively weak interaction between substrate and molecules resulting in an ultrashort recovery time of the order of nanoseconds. O2 and water introduce localized states in the upper valence region but do not alter the semiconducting nature of WSi2N4 nor its band-gap size apart from a minor variation of a few tens of meV. Exploring the same scenario in the presence of photogenerated electrons and holes, we do not notice any substantial difference except for O2 chemisorption when negative charge carriers are in the system. In this case, monolayer WSi2N4 exhibits signs of irreversible oxidation, testified by an adsorption energy of -5.5 eV leading to an infinitely long recovery time, a rearrangement of the outermost atomic layer bonding with the pollutant, and n-doping of the system. Our results indicate stability of WSi2N4 against H2O and CO2 in both dark and bright conditions, suggesting the potential of this material in nanodevice applications. [ABSTRACT FROM AUTHOR]

In this study, we report the efficient removal of organic dyes from aqueous solutions using a newly synthesized pyrene-appended Zn(II)-based metal–organic framework (MOF), ZnSiF6Pyrene MOF, with the chemical formula C52H32F6N4SiZn·4(CHCl3). The MOF was synthesized through a facile method at room temperature using a dipyridylpyrene ligand and ZnSiF6 metal source, resulting in a highly crystalline structure with pyrene functional groups forming the framework. The synthesized MOF was characterized using various analytical techniques, including Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD) analysis, and scanning electron microscopy (SEM). Thermal stability was assessed using thermogravimetric analysis (TGA), while the surface area of the MOF was determined using a Brunauer–Emmett–Teller (BET) surface analyzer. Furthermore, the single-crystal X-ray diffraction (SCXRD) structure was studied to authenticate its solid-state structure. The as-synthesized MOF exhibited remarkable adsorption capacity towards various organic dyes, including Congo red (CR), rhodamine B (RhB), and methyl violet (MV), due to its ample surface area and strong π–π interactions between the pyrene moieties and dye molecules, as demonstrated by experimental and in silico docking studies. The photocatalytic degradation of MV dye was also investigated. Detailed trapping tests indicate that hydroxyl (˙OH) and superoxide (O2˙−) radicals are likely the primary active species responsible for the photodegradation of the dye under study. Furthermore, the photocatalytic property of the MOF was investigated under visible light irradiation, demonstrating excellent ability to generate singlet oxygen. This study highlights the potential of pyrene-appended Zn(II)-based MOFs as promising materials for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Cobalt magnesium ferrite nanoparticles, with the chemical formula Co0.5Mg0.5Fe2O4 (CMFO), were synthesized via co-precipitation and subjected to annealing at 200–800 °C with a step size of 200. Thermal analysis for the as-dried sample was investigated through thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The presence of a plateau region in the DTA curve above 366 °C, combined with the slight weight loss noted in the TGA curve, indicates that the ferrite sample, specifically CMFO, has successfully transitioned into its final phase. X-ray diffraction and Fourier transform infrared spectroscopy (FTIR) analysis unveiled the formation of spinel CMFO NPs belonging to the Fd-3m space group. The Williamson–Hall method showed particle size increasing from 8.20 to 52.15 nm and tensile microstrain decreasing from 6.90 to 1.84 × 10−3 with higher annealing temperatures, noted by the shift of the (311) plane. TEM images confirmed the formation of smaller nanoparticles with minimal agglomeration. Particles of nearly uniform size are achieved at the optimum annealing temperature of 600 °C, owing to its narrow distribution profile. The experimental magnetization data were analyzed using the Langevin function and the law of approach to saturation to determine the saturation magnetization, spanning from 15.46 to 43.90 emu/g. The magnetic characteristics of the annealed samples exhibited a rise in coercive force, reaching up to 349.74 Oe with the elevation of the annealing temperature. The range of attributes exhibited by CMFO makes it highly advantageous for various applications, including sensor technology, high-frequency devices, and energy storage devices. [ABSTRACT FROM AUTHOR]

'Rhythmite', Ca29(SiO4)8Cl26, an anthropogenic calcium chloride silicate from the Chelyabinsk coal basin (South Ural, Russia), was investigated using chemical microprobe analysis, in situ single-crystal X-ray diffraction analysis (27–727 °C), and Raman spectroscopy. 'Rhythmite' is orthorhombic, Pnma: a = 17.0749(6), b = 15.1029(5), c = 13.2907(4) Å, and V = 3427.42(18) Å3 (R1 = 0.045). The crystal structure of 'rhythmite' consists of a porous framework formed by Ca-O bonds and SiO4 tetrahedra with additional Ca2+ cations and Cl− anions in the structure interstices. The framework is built up from multinuclear [Ca15(SiO4)4]14+ fundamental building blocks (FBBs) cut from the crystal structure of α-Ca3SiO4Cl2 ('albovite'). The FBBs are linked by sharing common Ca atoms to form a network with an overall pcu topology. The empirical chemical formula was calculated as Ca29.02(Si7.89Al0.05P0.05)Ʃ7.99O32Cl26 (on the basis of Cl + O = 58). 'Rhythmite' is stable up to 627 °C and expands slightly anisotropically (αmax/αmin = 1.40) in the ab and bc planes and almost isotropically in the ac plane (α33/α11 = 1.02) with the following thermal expansion coefficients (×106 °C−1): α11 = 14.6(1), α22 = 20.5(4), α33 = 15.0(3), and αV = 50.1(6) (room temperature). During expansion, the silicate tetrahedra remain relatively rigid with average bond length changes of less than 0.5%. A structural complexity analysis indicates that 'rhythmite' is complex, with IG,total = 920.313 (bits/u.c.), which significantly exceeds the average value of structural complexity for silicates and is caused by the modular framework construction and the presence of a large number of independent positions in the crystal structure. [ABSTRACT FROM AUTHOR]

Prussian blue analogs (PBAs) are appealing cathode materials for sodium-ion batteries because of their low material cost, facile synthesis methods, rigid open framework, and high theoretical capacity. However, the poor electrical conductivity, unavoidable presence of [Fe(CN)6] vacancies and crystalline water within the framework, and phase transition during charge–discharge result in inferior electrochemical performance, particularly in terms of rate capability and cycling stability. Here, cobalt-free PBAs are synthesized using a facile and economic co-precipitation method at room temperature, and their sodium-ion storage performance is boosted due to the reduced crystalline water content and improved electrical conductivity via the high-entropy and component stoichiometry tuning strategies, leading to enhanced initial Coulombic efficiency (ICE), specific capacity, cycling stability, and rate capability. The optimized HE-HCF of Fe0.60Mn0.10-hexacyanoferrate (referred to as Fe0.60Mn0.10-HCF), with the chemical formula Na1.156Fe0.599Mn0.095Ni0.092Cu0.109Zn0.105 [Fe(CN)6]0.724·3.11H2O, displays the most appealing electrochemical performance of an ICE of 100%, a specific capacity of around 115 and 90 mAh·g−1 at 0.1 and 1.0 A·g−1, with 66.7% capacity retention observed after 1000 cycles and around 61.4% capacity retention with a 40-fold increase in specific current. We expect that our findings could provide reference strategies for the design of SIB cathode materials with superior electrochemical performance. [ABSTRACT FROM AUTHOR]

New Nd3+-doped cadmium molybdato-tungstates with the chemical formula of Cd1−3x▯xNd2x(MoO4)1−3x(WO4)3x (where x = 0.0283, 0.0455, 0.0839, 0.1430, 0.1875, 0.2000, 0.2500, and ▯ denotes a vacant site in the crystal lattice) were successfully synthesized by the high-temperature solid state reaction method, using CdMoO4 and Nd2(WO4)3 as the initial reactants. The structure and change in their lattice parameters as a function of Nd3+ ion concentration were investigated by the XRD (X-ray diffraction) method. The surface morphology and grain size of the doped materials were characterized by SEM (scanning electron microscopy). Their thermal properties and initial reactants were analyzed by DTA-TG (differential thermal analysis coupled with thermogravimetry) techniques. The optical properties of the Nd3+-doped cadmium molybdato-tungstates, such as optical band gap, were determined by UV–vis–NIR (ultraviolet–visible–near infrared) spectroscopy. The EPR (electron paramagnetic resonance) technique provided information on the type of magnetic interactions between Nd3+ ions. [ABSTRACT FROM AUTHOR]

Objective: Novel azo-linked substituted sulfonamides were synthesized via diazo coupling with the molecular formula (C9H10N4O2S2, C11H11N3O2S) and characterized by FT-IR, UV-vis, HR-MS, and 1H NMR spectroscopy techniques. The photophysical studies were carried out using experimental techniques. Absorption and fluorescence maxima of all the synthesized molecules were determined by using different solvents. Our synthesized mono-azo derivatives are interested in identifying the cellular target site for sulfonamides (F1-F2) and (P1-P2). The newly synthesized compounds were examined for their in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli strains. Methods: In this study, we focused on the sulfonamide architecture. Antibacterial activity of compound (F1), (F2), (P1), and (P2) derivatives was studied by measuring the diameter of the inhibition zone, using the Disc-agar diffusion method. Results and Discussion: Density functional theory was used to demonstrate the electronic and optical properties of the synthesized molecules. In the correlation between the HOMO–LUMO energy gap, the derivative (F1) shows a higher (3.9866 eV) and (F2) shows a lower (3.2063 eV) excitation energy. The synthesized compound (F1) looks into antibacterial activity, exhibited more zone inhibition 25 mm in the concentration 75 µL/mL in gram-negative bacteria when compared with the common antibiotic Ciprofloxacin. Additionally, the results emerged from the in silico molecular docking studies the compound (F2) showed highest binding energy against cyclin-dependent kinase (ΔGb = –9.8 kcal/mol). Conclusions: The synthesized four mono-azo sulfonamide derivatives (F1), (F2), (P1), and (P2) are reported in photophysical, CDFT, antibacterial, and molecular docking studies with relevant results. [ABSTRACT FROM AUTHOR]

We report a theoretical investigation of a new carbon nanobelt called Hexa-Penta-belt with molecular formula C $_{42}$ 42 H $_{18}$ 18 . Hexa-Penta-belt is a variation of the synthesised Methylene-bridged[6]cycloparaphenylene (M-b[6]CPP) with molecular formula C $_{42}$ 42 H $_{24}$ 24 . Hexa-Penta-belt consists of carbon pentagon and hexagon rings and was inspired by the Penta-belt (theoretically derived from the penta-graphene sheet), the [12]cyclophenacene, and the M-b[6]CPP synthesised by Itami and Segawa [1]. Using Density Functional Theory (DFT), we calculated Hexa-Penta-belt electronic, optical, and thermodynamic properties and their vibrational frequencies. Hexa-Penta-belt is a structurally and thermally stable molecule, as Quantum Molecular Dynamics (QMD) showed. The results exhibited that the Hexa-Penta-belt has excellent electronic stability comparable to C $_{60}$ 60 , and it behaves as a semiconductor with a gap estimated at 0.89 eV. It absorbs in the ultraviolet and the visible region (corresponding to the violet, green, and red colours) presenting an absorption more consistent in the visible region than M-b[6]CPP, which could indicate application, for example, as an optical nanosensor. We verified through the carbon atom binding energy that Hexa-Penta-belt is an intermediate molecule between Penta-belt and [12]cyclophenacene. [ABSTRACT FROM AUTHOR]

To investigate the oxygen adsorption characteristics of coal with different moisture contents, a molecular model of bituminous coal from Datong coalfield was constructed based on 13C-NMR and XPS analysis, combined with molecular mechanics (MM) and molecular dynamics (MD) methods. The oxygen adsorption characteristics of coal were studied using the Grand canonical Monte Carlo (GCMC) method at a temperature of 293.15 K, with a pressure range of 0–10 MPa, and moisture contents of 3.27%, 5.13%, 6.92%, and 8.65%, respectively. The results show that the molecular formula of the Datong bituminous coal structure model is C159H134O35N2S, with a density of 1.35 g/cm3. High moisture content coal has a lower molecular surface area and porosity, and oxygen adsorption on coal molecules follows type I isotherms. The amount of physical oxygen adsorption decreases with increasing moisture content. The heat of physical adsorption is negatively correlated with pressure, and high moisture content accelerates the decrease in heat of physical adsorption caused by increased pressure. [ABSTRACT FROM AUTHOR]

A large data set of over 30 thousand organic compounds containing carbon, nitrogen, oxygen, fluorine, and hydrogen was collected, and the density of each compound was predicted by 1D descriptors derived from its molecular formula and 2D descriptors derived from its constitutional structural features. The 2D structural features are composed of Benson's groups, corrected groups, and 2D structural features of the whole molecular structures. All the descriptors were extracted by an in-house program in Java with a function to ensure that each atom (or bond) of molecules is represented by Benson's groups once for atom-based (or bond-based) descriptors. Partial least square (PLS) and random forest (RF) methods were used separately to build models to predict the density. Further, the variable selection of descriptors was performed by variable importance of RF. For partial least square, the combination of the models constructed by descriptors based on the atoms and the bonds achieved the best results in this paper: for the cross-validation of the training set, the Pearson correlation coefficient (R) = 0.9270, mean absolute error (MAE) = 0.0270 g·cm−3, and root mean squared error (RMSE) = 0.0426 g·cm−3; for the prediction of the test set, R = 0.9454, MAE = 0.0263 g·cm−3, and RMSE = 0.0375 g·cm−3. [ABSTRACT FROM AUTHOR]

A new series of 20-component fluorite-based compositionally complex oxides (20CCFBO x Nb/Ta) with the general chemical formula (15RE 1/15) 2 x +1 (Ce 1/3 Zr 1/3 Hf 1/3) 3–3 x (Nb 1/2 Ta 1/2) x O 8- δ (0 ≤ x ≤ 1, where 15RE 1/15 = La 1/15 Pr 1/15 Nd 1/15 Sm 1/15 Eu 1/15 Gd 1/15 Tb 1/15 Dy 1/15 Y 1/15 Ho 1/15 Er 1/15 Tm 1/15 Yb 1/15 Lu 1/15 Sc 1/15) are synthesized. Despite that the Gibbs phase rule allows for the existence of up to 20 phases at the thermodynamic equilibrium, 17 of the 20CCFBO x Nb/Ta compositions synthesized in this study all possess single ultrahigh-entropy phases in fluorite, pyrochlore, or weberite structure, as shown by X-ray diffraction (XRD). Only < 1 vol% of secondary phases are observed in two compositions near the phase-transition points. With changing compositional variable x , this series of 20CCFBO x Nb/Ta undergoes an abrupt fluorite-pyrochlore transition at x = ∼0.27 and an abrupt pyrochlore-weberite transition at x = ∼0.87. Careful characterization reveals abrupt changes of order parameters at both phase transitions. In addition, weberite short-range ordering can persist into the long-range pyrochlore phase, which leads to the lowest thermal conductivities. [ABSTRACT FROM AUTHOR]

In this study, few number of pages from ancient manuscripts that have undergone significant damage, were analyzed using micro-Ion Beam Analysis (micro-IBA) including micro-PIXE, micro-RBS, and micro-STIM to identify the factors responsible for the deterioration of these manuscripts. The micro-PIXE results indicate that the yellow decoration ink that has suffered severe corrosion is composed of a combination of Cu and Zn pigments. Moreover, the micro-PIXE analysis reveals that Cu is the main element that forms the decoration of this manuscript. The studying the various Cu pigments, it was discovered that one of the Cu pigment types, which is made up of Cu mineral elements, is verdigris or copper acetate (II) with the chemical formula Cu (CH3COO)2. This pigment is highly susceptible to environmental moisture. As a result, favorable environmental conditions such as optimal humidity and elemental composition like Cu can cause local oxidation of paper to destroys the paper substrate. Furthermore, the results demonstrate that the black ink used to write the text in these manuscripts are carbon-based and do not contribute to the corrosion of the paper. However, the micro-RBS analysis indicates that the ink has fully permeated and diffused in the bulk of paper and it increased the corrosion effect. [ABSTRACT FROM AUTHOR]

Atmospheric aerosols in megacities impact air quality and public health. However, limited information exists on the detailed molecular composition of organic aerosols in urban areas. This study characterized the molecular composition of organic aerosols (OA) in Shanghai, Beijing and Guangzhou, China, during summer and winter of 2021. Liquid chromatography-orbitrap mass spectrometry detected 4536−5560 and 2067− 3489 organic molecular formulas in positive (ESI+) and negative (ESI−) electrospray ionization modes, respectively. CHO and CHON compounds accounted for over 80% and 60% of total abundance in ESI+ and ESI−, respectively, suggesting their significant contribution to urban OA. The number and abundance percentages of CHO showed obvious seasonal variation, with more CHO in summer than in winter, while CHON exhibited the opposite trend in Beijing and Shanghai. Compared with winter, a lower unsaturation degree, reduced aromaticity, and higher oxidation state of OA in summer were observed in Beijing and Shanghai, while these seasonal variations were not as obvious in Guangzhou, likely due to regional climate differences. The number percentage of common compounds between Beijing and Shanghai was higher than that between Guangzhou and Beijing (or Shanghai). Nitroaromatic compounds were more prevalent in winter than in summer. Further analysis of atmospheric formation relevance and precursor-product pairs suggested that CHON compounds are derived from the oxidization or hydrolyzation processes, revealing potential chemical transformations of these aerosols. This study characterized the chemical makeup of organic aerosols, providing insight into their sources and characteristics in these cities. [ABSTRACT FROM AUTHOR]

Recent studies have shown that high dietary fructose intake enhances intestinal tumor growth in mice. Our previous work indicated that glucose enables hypoxic colorectal cancer (CRC) cells to resist receptor-interacting protein (RIP)-dependent necroptosis. Despite having the same chemical formula, glucose and fructose are absorbed through different transporters yet both can enter the glycolytic metabolic pathway. The excessive intake of dietary fructose, leading to its overflow into the colon, allows colonic cells to absorb fructose apically. This study explores the mechanisms behind apical fructose-mediated death resistance in CRC cells under hypoxic stress. Utilizing three CRC cell lines (Caco-2, HT29, and T84) under normoxic and hypoxic conditions with varying fructose concentrations, we assessed lactate dehydrogenase (LDH) activity, RIP1/3 complex formation (a necroptosis marker), and cell integrity. We investigated the role of fructose in glycolytic-mediated death resistance using glycolytic inhibitors iodoacetate (IA, a glycolytic inhibitor to glyceraldehyde 3-phosphate dehydrogenase), and UK5099 (UK, an inhibitor to mitochondrial pyruvate carrier). Our findings reveal that apical fructose prevents the hypoxia-induced RIP-dependent necroptosis in Caco-2 and HT29 cells. Fructose exposure under hypoxia also preserved epithelial integrity. IA, but not UK, blocked fructose-mediated glycolytic metabolite production and necrosis, indicating that anaerobic glycolytic metabolites facilitate death resistance. Notably, fructose treatment upregulated pyruvate kinase (PK)-M1 mRNA in hypoxic Caco-2 and HT29 cells, while PKM2 upregulation was exclusive to HT29 cells. In conclusion, apical fructose utilization through glycolysis effectively inhibits hypoxia-induced RIP-dependent necroptosis in CRC cells, shedding light on potential metabolic adaptation mechanisms in the tumor microenvironment and suggesting novel targets for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Through hydrothermal-induced interfacial reconstruction treatment, a multifaceted combination involving the spinel phase, oxygen vacancies, and reduced manganese is orchestrated to improve the anionic redox reversibility. The designed sample exhibits excellent rate capability and cycling stability, with ultra-low voltage decay of 0.91 mV cycle−1 after 150 cycles. [Display omitted] • Integrated introduction of spinel phase, oxygen vacancy, and reduced manganese in Li-rich layered oxides. • Enhanced initial couloumbic efficiency, superb rate capability, and advanced cycling stability with ultra-low voltage decay. • Chemical formulas unveil the underlying mechanism of surface defect engineering. • The modified sample has a 1.658% cell volume change, close to the "zero strain" of 1 %. • Density functional theory calculations provide comprehensive and in-depth insights. Cobalt (Co)-free lithium (Li)-rich layered oxides (LLOs) have emerged as promising cathode materials for the next generation of Li-ion batteries, attributed to their competitive market positioning and high energy density. Nevertheless, challenges arise from surface oxygen loss due to irreversible anionic redox reactions, leading to severe voltage and capacity decay that hinder the large-scale adoption of LLOs. Herein, we present an innovative, facile, and environmentally friendly hydrothermal approach to induce surface reconstruction of Li 1.2 Mn 0.6 Ni 0.2 O 2 material. A multifaceted combination involving the spinel phase, oxygen vacancies, and reduced manganese is orchestrated to alleviate the irreversible oxygen redox and impressively enhance Li-ion diffusion. The modified sample, owing to this surface transition, demonstrates low-strain and low-distortion properties along with a substantial improvement in structural stability, supported by both experimental validations and theoretical studies. As a result, the engineered sample exhibits exceptional capacity retention of 97.12% after 150 cycles at 1C, with an ultra-low voltage decay (0.91 mV cycle−1). Additionally, noteworthy enhancements in initial coulombic efficiency and rate performance are also observed. This straightforward surface defect engineering method offers a pathway to developing "low-strain" LLOs with superior electrochemical performance, thereby laying a solid foundation for future commercial applications. [ABSTRACT FROM AUTHOR]

Rationale: Phosphorotungstic acid (PTA) has many applications, especially in the field of catalysis, due to its structural properties. However, the structure of PTA is studied mainly using theoretical methods. Matrix‐assisted laser desorption/ionization (MALDI) has the potential to be an effective method for the experimental study of heteropolyacids. Limitations of MALDI are the high molecular weight of the particles and the complex distribution of isotopic peak intensities. Both problems can be solved by automatically identifying observed signals by generating hypothetical molecular formulas and estimating their isotopic distributions. Methods: Phosphotungstic acid was studied under conditions of laser desorption/ionization in the absence and in the presence of the matrix. Three types of matrices were used: 2,5‐dihydroxybenzoic acid in water, α‐cyano‐4‐hydroxycinnamic acid in acetonitrile, and sinapic acid (SA) in tetrahydrofuran. Part of the peaks in the resulting mass spectra was identified using in‐house developed software that implements the automated isotopic distribution brute force. Results: The most informative mass spectra were obtained using SA as the matrix, which enabled the detection of particles containing PTA dimers for the first time. The compositions of particles incorporating PTA dimers were determined in an automated manner and can be written as [H3PW12O40]2·2H2O (m/z = 5791.2 Da) and [H3PW12O40]2·4H2O (m/z = 5836.5 Da). Other observed species included (WO3)n·PO3−, HPO2·(WO3)n, and WO2·(WO3)n clusters, with the latter containing W in mixed oxidation states. Conclusions: The combined use of MALDI and an automated identification procedure provided valuable experimental data on the structure and fragmentation of phosphotungstic acid. To the best of our knowledge, this study was the first to report on particles containing phosphotungstic acid dimers. [ABSTRACT FROM AUTHOR]

Farnesol is a natural acyclic sesquiterpene alcohol, found in various essential oils such as, lemon grass, citronella, tuberose, neroli, and musk. It has a molecular mass of 222.372 g/mol and chemical formula of C₁₅H₂₆O. The main objective of this study was to assess the effect of farnesol on mTOR and its two downstream effectors, p70S6K and eIF4E, which are implicated in the development of cancer, via molecular dynamic simulation, and docking analysis in an in silico study. A multilayer, primarily computer-based analysis was conducted to assess farnesol's anticancer potential, with a focus on primary cancer targets. From the calculations performed, farnesol showed a binding affinity of – 9.66 kcal/mol, followed by binding affinity of – 7.4 kcal/mol and – 7.8 kcal/mol for mTOR, p70S6K and eIF4E respectively. Rapamycin showed the binding affinity of – 10.45 kcal/mol for mTOR, for p70S6K and eIF4E the calculated binding affinity was – 10.65 kcal/mol and 8.16 kcal/mol respectively. The binding affinity of farnesol was comparable to the standard drug rapamycin indicating its potential as an mTOR inhibitor. Molecular dynamics simulations suggest that the ligands (farnesol and rapamycin) were well trapped within the active site of the protein over a time gap of 50 ns. It is clear that farnesol showed relatively stable MD simulation results, with minor fluctuations and maintains a consistent binding orientation, suggesting a strong and stable interaction with the target proteins when compared to simulation data of standard drug. This study explores the potential of farnesol as an anticancer agent through an in-silico approach, focusing on its interaction with mTOR and its downstream effectors. Inhibition of mTOR signaling pathway may be responsible for the anticancer effect of farnesol. As this pathway plays a crucial role in cell proliferation and survival, making it a significant target in cancer research. [ABSTRACT FROM AUTHOR]

In the present work, we have investigated the crystal structure and magnetic properties of the Y2.97Gd0.03Fe5−xLaxO12 (Gd-La co-doped YIG) compound (0.00 ≤ x ≤ 0.05) obtained by the citrate sol–gel method. Rietveld refinement of the X-ray diffraction patterns provided the lattice parameter (a) values, which increased from 12.387(2) to 12.468(2) Å as the La3+ content increased. Raman measurements confirmed the single-phase formation, whereas transmission electron microscopy (TEM) revealed elongated and irregular particles. The Mössbauer spectroscopy confirmed the presence of Fe3+ and Fe2+ cations and the coexistence of Fe2+ and La3+ cations in the octahedral and tetrahedral sites. Nonetheless, using a phenomenological model, it was suggested that the Fe2+ and La3+ ions tend to occupy preferentially the octahedral sites in the YIG structure. Further, the correspondence between the experimental and theoretically predicted saturation magnetization values indicated that the compound stoichiometry can be described by the chemical formula Y3+2.97Gd3+0.03Fe3+5−x−yLa3+xFe2+yO2−12−y/2. Magnetic parameters such as saturation magnetization, anisotropy constant, remanent magnetization, and coercive field values were computed and discussed as a function of cations distribution in the YIG crystal structure. [ABSTRACT FROM AUTHOR]