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An additive-free, low-viscosity polyalphaolefin (PAO) has been oxidized under pure oxygen at elevated pressure and temperature. This biodegradable PAO base oil is a promising candidate for use as a motor-gear lubricant in electrical drive systems. The oxidation behavior is systematically investigated to evaluate its thermal stability and long-term performance. Rheological measurements are performed to assess viscosity, water content is quantified, tribological tests determine the coefficient of friction, and Fourier-transform infrared spectroscopy is used to monitor chemical changes during oxidation. All analytical methods consistently revealed a two-step oxidative degradation process. It is proposed that the first stage involves the formation of carbonyl compounds and water without compromising lubrication properties, while the second stage—triggered by hydrolysis of oxidation products—leads to chain scission and initiates the desired degradation. This two-stage mechanism is discussed in the context of technological functionality and sustainability requirements for next-generation electric drive lubricants.

Benzothiazoles, including the cationic thioflavin T and its variants, are of immense interest because of their therapeutic potential and applications as biomolecular fluorescence probes. This study investigates the photophysics of an interesting benzothiazole derivative, TEG-BTA-2, that combines a neutral thioflavin T type of moiety (BTA-2) with a tetraethylene glycol chain (TEG). Unlike thioflavin T, TEG-BTA-2 is highly fluorescent and shows multiple prototropic transformations. Monoprotonated TEG-BTA-2 is found to exist in two isomeric forms, each having characteristic absorption, emission, and fluorescence lifetimes. Furthermore, TEG-BTA-2 shows strong affinity toward the cavitands α-, β-, and γ-cyclodextrins (CDs). The binding constants of TEG-BTA-2 with the cavitands are considerably higher than that of thioflavin T, which is attributed to its neutral charge and favorable hydrophobic/H-bonding interactions provided by the TEG chain. Interestingly, it is found that the size of the macrocyclic cavity plays a pivotal role in controlling the fluorescence response of TEG-BTA-2 due to formation of complexes with different stoichiometries. In contrast to the fluorescence enhancement observed with αCD and βCD, the interaction of TEG-BTA-2 with γCD leads to fluorescence quenching. These results provide valuable insights for development of thioflavin T-inspired benzothiazole molecules as fluorescent markers and diagnostic agents.

A series of 23 heterocyclic derivatives incorporating 1,2,4-triazole and oxadiazole motifs are synthesized via cyclization of thiocarbamoylimidates with hydrazine salts. Reaction parameters including solvent, base, and temperature are systematically optimized and very good results are obtained in the environmentally friendly reaction media composed of water and ethanol, under mild conditions of temperature (40 °C). The reaction is very versatile and allows for the introduction of a wide variety of functional groups. All the new compounds are submitted to in silico evaluation of their drug potential using the SWISS-ADME tool. Several compounds of both families did not violate any drug likeness rules, making them potential candidates for further evaluation of their biological activity and structural optimization.

Lead contamination in the environment severely threatens human health due to its high toxicity, particularly in water sources. Exposure to lead ions (Pb²⁺) can cause neurological disorders, kidney damage, and developmental impairments, necessitating the development of sensitive and selective detection methods. Biomass-derived fluorophores, such as carbon dots (CDs), have emerged as eco-friendly and cost-effective alternative sensors that offer high sensitivity while overcoming the limitations of conventional techniques. This work reports a fluorescence-quenching sensor for lead ion (Pb²⁺) based on CDs synthesized from biomass (Saccharum spontaneum). The CDs are synthesized via a hydrothermal process. Optical studies reveal a fluorescence quenching of CDs in the presence of Pb²⁺ ions due to the complex formation of CDs through functional groups, enabling highly sensitive lead detection. The CDs exhibit a low detection limit of 376 nM, demonstrating its potential as a reliable lead sensor. These CDs are further explored as fluorescent ink for anticounterfeiting applications.

This research work demonstrates the engineering of rGO/Fe₃O₄ based heterojunction as cost-effective, highly efficient, and robust photocatalyst with readily recoverable and reusable characteristics. Herein, the Fe₃O₄ nanoparticles have been synthesized from the waste toner powder collected from used cartridges for advancing a magnetically separable photocatalyst. The Fe₃O₄ nanoparticles have been decorated on rGO sheets for enhancing the conductivity and retarding the recombination rate of photogenerated electron–hole pairs, as reflected by the decrease in photoluminescence intensity for rGO/Fe₃O₄ relative to pure rGO and Fe₃O₄. Additionally, the specific surface area has also improved from 12.93 m² g⁻¹ for Fe₃O₄ to 115.58 m² g⁻¹ in the case of rGO/Fe₃O₄. Henceforth, the rGO/Fe₃O₄ nanocomposite showcases remarkable performance for the removal of various pollutants like, rhodamine B (RhB) (98.5%), methylene orange (93.8%), methylene blue (99.99%), and tetracycline hydrochloride (95.4%) after 30, 40, 20, and 40 min of simulated solar light exposure, respectively, by utilizing 0.2 mg ml⁻¹ of photocatalyst. Furthermore, it degrades 74.3% of RhB pollutant with very high concentration of 30 mg L⁻¹ within 80 min of light irradiation. Additionally, this work also manifests the impact of different parameters, like dosage of photocatalyst and initial concentration of the pollutants and mixing of diverse pollutants on the photodegradation efficiency of nanocomposite. The scavenger's study is performed to investigate the active species involved in the photodegradation process. Furthermore, the role of built-in potential at the interface of heterojunction is thoroughly discussed to understand the mechanistic intricacies of the charge transfer process during the photodegradation process.

To enhance the operating voltage window of supercapacitors (central part), electrolyte engineering (bottom part) is implemented. Ethylene carbonate (EC, white balls) with superior electrochemical stability preferentially absorbs onto the activated carbon electrode (gray, left part). Meanwhile, EC restricts the molecular mobility of fragile acetonitrile (AN, green rugby-ball) through strong interactions（right part). The AN decomposition is effectively avoided and the systematic stability is enhanced. More information can be found in the Research Article by Huachao Yang and co-workers (DOI: 10.1002/cplu.202500367).

Nitrosoarenes exhibit a variety of biological and pharmacological activities. This review uncovers their utility as therapeutic agents, which extends to oxidative stress regulation, DNA damage and repair interaction, cyclin-dependent kinase inhibitors, anticancer, antiviral, antibacterial, antifungal, antiparasitic, anti-inflammatory, and other miscellaneous effects. The synthesis of the most relevant targets is also reviewed.

The electrochemical characterization of DNA films with different base mismatches or with Cu^II- or Ag^I-mediated pairs was carried out to assess possible immobilization and interaction effects. Toward this end, 3-hydroxy-2-methylpyridin-4(1H)-one (H), imidazole-4-carboxylate (K), purine-6-carboxylate (P), and 7-deaza-6-pyrazolylpurine (D) were used as artificial metal-binding nucleobases. Cyclic voltammetry and square-wave voltammetry confirmed the immobilization of suitably modified oligonucleotides on Au electrodes. The incorporation of the metal ions into the base mismatches to form metal-mediated base pairs showed a negligible effect on the peak potentials. Ambiguous electrochemical impedance spectroscopy results were obtained for DNA with metal-mediated base pairs, as some duplexes showed no effect of metal ion addition, while others showed variable charge transfer resistance (R_CT) with no discernible pattern. Notably, the formation of Ag^I-mediated base pairs induced larger relative changes in R_CT compared to Cu^II-mediated base pairs. Amongst the latter, only strands containing the artificial nucleobase H showed statistically relevant sequence- and distance-dependent charge transfer changes upon metalation. The data indicate that neither nucleobase charge nor nucleobase size directly correlates with the charge transfer resistance, but suggest that changes in DNA film stiffness and hence permeability outweigh other effects.

Developing technologies to capture, purify, and reuse potent greenhouse gases such as sulfur hexafluoride (SF₆) is crucial because of their high global warming potential. Porous solid matrices are promising candidates for this purpose, due to their high surface areas and pore volumes. Herein, two coconut shell–derived activated carbons (AC) (CS-CO₂ and CS-ZnCl₂), obtained through physical and chemical activation, are evaluated and compared with two commercial adsorbents: an AC monolith (ACM) and a metal-organic framework. The adsorption capacities for SF₆ and nitrogen (N₂) are measured gravimetrically at three temperatures: 283.15, 303.15, and 323.15 K. The experimental data are fitted using the Toth model, and the impact of temperature and pressure on the adsorption performance is analyzed. The order of SF₆ adsorption capacity is: ACM > CS-ZnCl₂ > Fe-BTC > CS-CO₂, reflecting dependence on surface area. Selectivity for SF₆/N₂ separation is evaluated using Ideal Adsorbed Solution Theory, with ACM exhibiting the highest adsorption capacity due to its selective separation properties. These findings contribute to the understanding and selection of efficient adsorbent materials for SF₆ separation and recovery, providing valuable insights for their future implementation in industrial gas treatment and environmental management applications.

Cyclodextrin is a typical macrocyclic molecule that can recognize and bind numerous guest molecules with specific structure and functional groups. The cyclodextrin-based supramolecular nanostructures, characterized by well-defined, ordered, compact, and regular molecular arrangements, are widely utilized in drug delivery, sensing, and light-harvesting systems. Their unique physicochemical properties have further expanded the scope of research in both biophysics and chemistry. In this review, we provide an overview of the concepts and applications of cyclodextrin-based supramolecular nanostructures, with a focus on their relevance to biochemistry and chemistry.