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In this study, we constructed a “turn-off” fluorescence probe for the specific detection of antiviral agents by preparing stable reserve solutions of 1,1,2,2-tetraphenylethylene (TPE), which notably exhibits the character of aggregation-induced emission (AIE). The fluorescent molecules were systematically characterized. The maximum excitation and emission peaks were located at 281 and 440 nm, respectively. We discussed the fluorescence response between TPE and antiviral agents, as well as the effects of certain single-variable factors. The % suppressed efficiency (%E) was calculated and the Stern–Volmer equation was analyzed. The results indicated that Cidofovir (CDV) can more effectively quench TPE based on the mechanism of internal filtration effect (IFE) and static quenching. We studied the linear correlation between fluorescence intensity and the concentration of CDV. The limit of detection (LOD) was found to be 0.2279 mg·L⁻¹. The recovery rates of CDV in blank samples ranged from 93.22%–97.90%. Additionally, different letters “L” were written using the prepared solutions under ambient light and UV light, respectively, demonstrating that the written contents were both readable and easily erasable. The specific recognition of CDV using TPE lays the groundwork for detecting CDV residues, which holds promising prospects for practical detection.

In this study, to make the most of biomass as raw material, carbon aerogel was fabricated by green synthesis and low-cost methods with high applicability. Pachyrhizus erosus-derived carbon aerogel (PCA) was synthesized through a simple process by hydrothermal freeze-drying combined with pyrolysis. The effect of pyrolysis temperature on the characterization and applications of PCA was investigated at 600, 700, and 800 °C. Characterization of PCA was analyzed by modern methods: scanning electron microscope, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), energy-dispersive X-ray (EDX), and nitrogen adsorption–desorption isotherms. With its diverse pore structure and bulk form, PCA was investigated for applications of oil and organic solvent adsorption and energy storage. From that, PCA becomes a potential material application in adsorption and energy storage with an oil adsorption capacity 31 times its volume and a specific capacitance of up to 349.9 F/g for PCA pyrolysis at 700 °C.

This study aims at elucidating the role of the polysaccharide skeleton (alginate versus chitosan) during the growth and shaping of HKUST-1 as porous beads. Although the two biopolymers afford an open porous hydrogel network, the freeze-drying step was crucial with water medium being inappropriate to preserve the crystalline framework of HKUST-1. Alternatively, drying in ethanol circumvented this drawback by keeping intact the structure of HKUST-1. However, a contrasting behavior was observed in the resulting polysaccharide@HKUST-1 beads, as HKUST-1 grown in alginate underwent a dramatic collapse, whereas self-standing, open porous microspheres could be obtained using the chitosan templating route. The resulting chitosan@HKUST-1 cryogel displays an enhanced CO₂ capture (2.67 mmol.g⁻¹) compared to its analogs shaped by alginate, making consequently chitosan a better option for structuring MOF-based adsorbents.

Modifying the wax crystal habit is useful for transporting and processing crude oil at low temperatures. Various polymeric pour point depressant (PPD) additives can aid in this maneuver differently. Various morphologies of polymeric additives (like comb, brush, centipede, etc.,) have been shown to lower the pour point of crude oil by providing several nucleation sites for wax precipitation. Out of the large array of materials available, it is challenging to forecast which one will act as a wax-crystal modifier on the crude oil under consideration. We propose, in this study, a detailed classification of wax-crystal modifier additives based on criteria such as linear or branched copolymers, the presence of crystalline or amorphous segments, aromatic units and their positions (such as in the backbone or branch), the ability to self-assemble or aggregate, etc. Accordingly, we synthesized additives from the maleic anhydride class having three different morphologies namely brush, combs, and centipedes, through free radical polymerization (FRP). The detailed characterization of these additives was carried out using structure-sensitive techniques, such as ¹H nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, and gel permeation chromatography. To evaluate the real-time performance of the as-synthesized additives, we selected crude oils from the South Kadi (SK), Limbodara (LM), and Nada (ND) oil fields of the Cambay basin, Gujarat, India having different levels of wax and asphaltenes. The rheological parameters of crude (with and without additive) were investigated using an Advance Rheometer AR-500. Depending on the additive capability to self-aggregate and the composition of the crude oil, the additive AMI-3 is the most effective for ND, EST-2 for LM, and A-18S for SK crude oils. Their 1000 ppm dose can reduce the pour point of these crudes up to 18 °C and improve their rheological parameters accordingly. Finally, we propose the mechanisms of pour point depression by these as-synthesized additives and carry out the microscopic imaging of the precipitated wax crystals from the blank and additive-treated crude oil.

The fourth period metal fluorides acting as a Lewis acid form binary compounds with nitrogen-containing bases (HCN, NHCH₂, and NH₃), which the calculations are carried out at the MP2 ab initio level with the AVTZ and AVQZ basis set and employed by the CBS method. AIM and IGMH analyses further indicate that the metal-N-bases (M─N) bonding exists in the binary complexes. The strength of interactions is ranging from −4.76 to −56.54 kcal/mol. M─N bonding exhibits a partially covalent nature characterized with a negative energy density and large interaction energy. With the decrease of electronegativity of the substituents on the Lewis base, the interaction energies increase. The M─N interaction is dominated by electrostatic interaction in all complexes, whereas induction and dispersion energies cannot be ignored either.

The photochromic properties of organic bromide salts prepared from 3,6-bis(bromomethyl)durene and nicotinic acid/methyl nicotinate were explored. UV exposure induced color changes, revealing distinct photoresponsive rates for each compound. Structural analysis, electron spin resonance (ESR), and DFT calculations elucidated the underlying mechanisms, highlighting the critical role of electron transfer and supramolecular interactions. This study provides structural insights to enhance the photochromic properties of non-viologen compounds.

The exceptional protective coating can extend the service life of the equipment in a severe marine environment. Carbon fibers (CFs), characterized by high tensile strength, elastic modulus, and excellent chemical resistance, serve as an appropriate filler for coating reinforcement. However, the inadequate fiber/matrix interfacial adhesion makes it difficult to prepare high performance CF-reinforced composites. Therefore, we synthesized a kind of silk fibroin modified CF (CF─SF) as a reinforced-additive for strengthening the corrosion resistance and anti-erosion properties via improving the interfacial adhesion between CFs and resin matrix. The impedance value of composite coating including 1 wt% CF—SF (CF—SF/EP) was 1.65 × 108 Ωˑcm² after immersion, which was two orders of magnitude greater than that of the pure EP coating. In addition, the erosion experiments results showed that the volume loss of EP/CF—SF coating was 132.6 mm³, which decreased by 36.4% and 17.4% compared with EP/CF and EP/CF─O, respectively. The average depth of the CF—SF/EP coating (0.27 mm) was the shallowest among the coatings. Ultimately, we examined the protective mechanism of the CF–SF/EP coating.

This study investigates the development and optimization of activated carbon (AC) from corn silk (CS-AC) and corn silk hydrochar (CS-HC-AC) as a sustainable solution for water purification. For the first time, hydrothermal treatment and activation processes were employed, producing AC from corn silk with improved structural properties. CS-HC-AC exhibited a remarkable S_BET surface area of 331.233 m² g⁻¹, surpassing the 7.335 m² g⁻¹ of CS-AC. Key factors such as temperature, activation time, and activator rate were optimized (100% activator rate, 500 °C temperature, and 60 min activation time), with K₂CO₃ and ZnCl₂ identified as the most effective activators for CS-AC and CS-HC-AC, respectively. The resulting ACs showed high adsorption capacities for heavy metals (Cr(VI), Pb(II), and Ni(II)) and methylene blue dye.

Polyoxometalates (POM) are a class of inorganic metal oxides with distinctive structural characteristics, compositional versatility, high catalytic efficacy, and convenient storage properties. In recent years, POM have shown considerable potential for mimicking enzyme activities. Besides their biological activities, POM have been demonstrated to possess the ability to sense diseases and perform synergistic therapies based on their redox and near-infrared absorption properties. Similar to the metallic nanoparticles and the organic materials, these inorganic clusters also exhibit distinctive photothermal imaging and therapeutic properties. Based on this, the current review focuses exclusively on the application of POM in the photothermal therapy of tumors. Furthermore, the advantages and the potential issues associated with the current POM-based nanomaterials in tumor therapy are discussed and analyzed.

New polymeric spheres of sodium alginate (AlgNa) containing dicarboxylic acids—maleic acid (MA) and oxalic acid (OA)—were developed for adsorption of copper metal from water. Water adsorption capacity, elementary composition, structural, morphological, vibrational, and thermal properties were characterized by scanning electron microscopy (SEM), intumescence degree (IG), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and differential scanning calorimetry. SEM data revealed that functionalization with dicarboxylic acids affects the morphology and surface of the AlgNa matrix. Sample containing MA (0.35 ± 0.004 g) absorbs more water than the OA sphere (0.28 ± 0.007 g). XRD patterns showed that the AlgNa–MA and AlgNa samples exhibit an amorphous nature, whereas the AlgNa–OA sample has a partially crystalline phase. Adsorption experiments were conducted to analyze whether the synthesized spheres could be optimized to reach the best performance in copper adsorption. The adsorbents were most efficient at the highest dosage used (250 mg), corresponding to removal percentages of 84.54 ± 3.97% (AlgNa), 94.21 ± 3.04% (AlgNa–MA), and 84.22 ± 3.39% (AlgNa–OA). The energy-dispersive X-ray spectroscopy maps validated the incorporation of Cu²⁺ ions on the surface of the adsorbents. Kinetic and isotherm assays confirmed the highest efficiency of AlgNa–MA spheres.