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Tungsten (VI) hexachloride, WCl₆, and tungsten (VI) oxytetrachloride, WOCl₄, are of interest in a variety of technological applications. In the present work, complete vibrational assignments are provided for both molecules in the “free” state (i.e., in the gas phase or in solution) and in the solid state. The first inelastic neutron scattering spectra of both molecules in the solid state are recorded. The assignments are supported by density functional theory calculations. In all cases, the W–Cl stretching modes occur in the 300–400 cm⁻¹ range, and the Cl–W–Cl bending modes in the 100-250 cm⁻¹ range.

A combined Electrospray Infrared MultiPhoton Dissociation Mass Spectrometry (ESI-IRMPD-MS) and Density Functional Theory (DFT) investigation has allowed to elucidate the structural features of the species arising from the triple dehydration of D-fructose in the gas phase. The experimental workflow involves measuring and comparing the IRMPD spectra of different ionic populations: protonated 5-hydroxymethylfurfural [HMF·H]⁺ and the ionic species coming from the triple dehydration of the ammonium-D–fructose complex ([Fru·NH₄]⁺). The IR-photon induced fragmentation of [Fru·NH₄]⁺ reveals the coexistence of two ionic populations, which arise from of two independent not intercrossing fragmentation pathways of the ionic precursor. One population exhibits an IRMPD spectrum matching with the ([HMF·H]⁺) one and corresponding to a carbonyl-protonated structure. The second ionic product is its C2-protonated protomer, which lies 75 kJ/mol above the global minimum. The presence of a less stable protomer is most likely due to its gas-phase kinetic trapping. These findings contribute to a more refined understanding of gas-phase carbohydrate dehydration and isomer formation at the molecular level.

Heterogeneous catalytic selective hydrogenation (HCSH) of vegetable oils is a reactive pathway to maximize the fraction of monounsaturated oleic acid, a component of industrial interest, thanks to its stability and low-temperature properties. Kinetics of HCSH is usually interpreted by pseudo-first order laws, as previously done by this research group with data from batch tests on canola oil (Lindlar catalyst, 120–180 °C, 0.4–1.2 MPa): the pseudo-first order kinetics could interpret the observed phenomenon only by variable selectivities (i.e., ratios of kinetic constants). The present work proposes a refined modeling by Hougen–Watson approach. Detailed reaction mechanisms were hypothesized, challenging the following alternatives: (i) H₂ adsorption on the catalyst occured (Hinshelwood–Langmuir) or not (Eley–Rideal), (ii) H₂ adsorption was molecular or dissociative, (iii) H₂ adsorption was competitive or not with fatty acids adsorption, and (iv) reaction intermediates were formed or not. Six reaction mechanisms were developed with related kinetic rate laws for HCSH. Their kinetic parameters were regressed for the abovementioned experimental data by a purposely developed MATLAB script. The best mechanism was chosen based on the highest explained variance ($$) and the lowest number of parameters. Chemical–physical meaningfulness of regressed parameters for the best model was checked by comparison with the literature.

pH-sensitive ion-selective field effect transistors (ISFETs) are commercially available nowadays, offering high robustness, resolution, accuracy, and durability. A crucial drawback is their high price and permanent power demand. Incorporating commercially available small-sized ISFET sensors into battery-powered devices requires a thorough evaluation and the development of strategies to reduce power consumption. In this work, a direct comparison of three different commercial ISFETs is presented using a newly developed evaluation process that aims to investigate long-term performance. The different behaviors in conditioning, linearity, accuracy, response times, and long-term stability in detail are discussed. Furthermore, strategies to decrease power consumption are presented by adjusting the operating conditions and introducing an OnOff-protocol. It is found that all ISFETs have limitations in their overall performance with the best performers being 1) Winsense, with the highest slope of 59.7 mV pH⁻¹; 2) Microsens, with the highest potential output precision under the recommended working point conditions (±0.01−0.03 pH) with SD and reduced working conditions (± 0.01 pH) with WD; and 3) Sentron, with the highest stability under both power-reducing strategies. With the combination of both power-reducing strategies, the ISFET's power demand is reduced by 98.8%.

Formic acid is obtained as a byproduct of biomass pyrolysis and is used as a liquid organic hydrogen carrier due to its low decomposition temperature, enabling hydrogen production under mild conditions with noble metals. The decomposition of FA in the vapor phase using different rhenium phases (metal, carbide, and oxide) supported on graphite and carbon nanotubes was studied within a temperature range of 80–220 °C, in a fixed-bed reactor with a space velocity of 651 mL g_cat h⁻¹. The catalysts were characterized by N₂ adsorption–desorption, H₂-temperature-programmed reduction, transmission electron microscopy, temperature programmed desorption-ammonia, temperature programmed reaction-methanol, X-ray diffraction, and X-ray photoelectron spectroscopy. Graphite-supported catalysts achieved higher activity than carbon nanotube-supported ones, due to the higher rhenium dispersion on graphite. Catalytic reactions revealed that ReC/G exhibited superior performance at lower temperatures per active site, attributed to the rhenium carbide phase. High selectivity toward CO₂ was observed across all catalysts, except for ReOx/G at lower temperatures, where differences in active site characteristics likely influenced performance. ReC/G displayed the highest intrinsic activity, highlighting rhenium carbide as a more active phase than metallic or oxide rhenium.

A systematic investigation of the catalyst-free Strecker reaction is conducted in aqueous buffer, offering an efficient and green alternative that leads to α-aminonitriles without the need of chromatography. Optimization reveals that low pH and high buffer concentration significantly enhance conversion, with yields up to 97%. Broad substrate scope is demonstrated with various aldehydes, ketones, and amines, leading to key intermediates for natural and unnatural amino acids. Potassium cyanide and acetone cyanohydrin are established, latter as a safer and effective cyanide source, and reactions are conducted also in buffer–methyl tert-butyl ether mixed solvent further improving the methodology. It is hypothesized that, based on the similarity to cyanohydrin formation, the hydroxynitrile lyases (HNLs) might transform imines to aminonitriles. Adding AtHNL and HbHNL further accelerates the reaction suggesting an undiscovered reactivity of these enzymes.

This study investigates the influence of seasonal variation onthe phytochemicalcomposition and biological activities of Cistus creticus leaf extracts collected during spring, summer, autumn, and winter. Extracts are analyzed for phenolic and flavonoid contents and evaluated for antioxidant, enzyme inhibitory, anti-inflammatory, analgesic, antimicrobial, and photoprotective properties. Pronounced seasonal differences are observed. Spring and summer extracts, enriched in bioactive compounds, exhibit the strongest pharmacological potential, including notable antioxidant effects, potent enzyme inhibition, and high photoprotective capacity. The spring extract further demonstrates significant in vivo anti-inflammatory and analgesic effects, while the winter extract displays superior in vitro anti-inflammatory activity. These findings highlight the critical role of harvest season in modulating both phytochemical composition and bioefficacy. The superior performance of spring and summer extracts underscores the potential of C. creticus as a valuable natural source of antioxidants, enzyme inhibitors, and photoprotective agents. Overall, this work supports the strategic use of seasonal optimization to enhance the therapeutic and cosmeceutical applications of C. creticus.

Molecular networking has emerged as a new in silico tool for analyzing liquid chromatography–mass spectrometry (LC–MS) data for better annotation and elucidation of novel compounds and different pathways. Green synthesized nanoparticles (NPs) have gained considerable attention as a result of their effectiveness in possessing good antimicrobial activity. Their eco-friendly nature and cost-effective synthesis have positioned them as sustainable nanomaterials in various fields. However, not much is known about the mechanism underlying the green synthesis of NPs. Therefore, herein, the copper oxide NPs (CuO NPs) are fabricated, and ultrahigh performance liquid chromatography-quadrupole time of flight mass spectrometry based molecular networking is utilized to understand the phytochemical relationship between the crude extract and the NPs, outlining metabolites that might be involved in reduction. Moreover, CuO NPs synthesized from Citrus unshiu fruit peels are tested for their antimicrobial and cytotoxic activities. Various characterization methods, such as X-ray diffraction, UV–vis spectroscopy, scanning electron microscopy-energy dispersive X-ray analysis, Fourier transform infrared, dynamic light scattering, and transmission electron microscopy, are employed to provide comprehensive insights into the atomic and structural characteristics of NPs. Molecular network reveals the presence of different metabolites such as isosakuranetin-7-O-rutinoside, hesperidin, skullcapflavone II, homoorientin, eupatorin-5-methylether, scoparin, and vitexin, which are recognized as antimicrobial and reducing agents. Additionally, the synthesized CuO NPs show exceptional antibacterial efficacy with a low minimum inhibitory concentration on Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Salmonella typhimurium, highlighting the potential of using LC–MS to explain the antimicrobial properties and green synthesis pathway.

Triple-negative breast cancer (TNBC) is characterized by unique clinical and pathological traits, from which its aggressive nature and the absence of specific treatments are the most worrying. Prostaglandin E₁ (PGE₁) can affect the morphology of human breast tumor cell lines, but its potential therapeutic effects appear to be counteracted by its high degradability in physiological environments. For this reason, polylactic-glycolic acid polymeric microparticles (MPs) are developed to stabilize PGE₁ in damp conditions and enable sustained local release for the treatment of TNBC after surgical removal of the tumor mass. Specifically, the PGE₁ embedded MPs are produced using a double emulsion solvent-evaporation method, then analyzed through Mastersizer and scanning electron microscopy. Afterward, the encapsulation efficiency and the PGE₁ release are examined using liquid chromatography–mass spectrometry, and their stability at various storage temperatures is assessed. Finally, the carrier toxicity is evaluated in TNBC cells and colon adenocarcinoma epithelial cells, Caco-2. A reliable action on carcinogenic cells specific to breast cancer is observed. Although in vivo studies are still needed, these results open the way to using such a carrier for the intralesional delivery of PGE₁ and its use against TNBC.

A new series of β-carboline-{α-acylaminoamide}-bisindole hybrids (12a–l) is designed and synthesized employing an atom-economical one-pot Ugi four-component reaction (U-4CR), affording the target compounds in good yields. All synthesized compounds (12a–l) are characterized by NMR, infrared, and mass spectrometry and evaluated for their antibacterial activity against both Gram-positive and Gram-negative strains. Notably, compounds 12b, 12g, and 12h display comparable minimum inhibitory concentrations values (302–303 µg mL⁻¹) against multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa, showing markedly improved activity relative to their parent compounds 6 and 9, which show weaker inhibition (MIC = 308–623 µg mL⁻¹). Molecular docking studies of compounds 12g and 12h revealed favorable binding interactions with DNA gyrase, while density functional theory analysis supported their electronic reactivity. These findings highlight the potential of molecular hybridization in the development of novel antibacterial agents.