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SiO2‐TiO2 aerogel composites were synthesized by co‐gelation of a titanium tetrachloride in an aqueous silicic acid solution. As‐prepared hydrogels were hydrophobized by trimethylchlorosilane and then dried at 150 °C and ambient pressure condition. The resulting gel composites are typical 'pearl‐necklace' aggregate silica structure which is intertwined at the nanometer level with titania, yielding a three‐dimensional hydrophobic SiO2‐TiO2 interpenetrating network with an improved pore structure, BET surface area, and photocatalytic performance when compared to their calcined hydrophilic gels. A hydrophobic aerogel composite which is optimized in an L9(34) orthogonal array features a fast removal (<30 mins) of organic compounds (> 89% removal of methyl orange and humic acid) in a 10 mg/L solution under UV light exposure, in which ethanol‐water was used as co‐solvent. In comparison, the calcined hydrophilic xerogel shows 10‐fold longer degradation time (∼ 300 mins) to remove the same concentration waste from the water streams. A high and fast degradation for organic pollutants is reached by using hydrophobic aerogel composites with assistance of organic co‐solvent to eliminate the interface between gel surface and pollutant solution. [ABSTRACT FROM AUTHOR]

Silica (SiO2) based aerogel/xerogel materials have been received ever-growing attentions for versatile applications. However, the widespread applications are narrowed by the inert properties, fragile and brittle natureof silica materials and cumbersome preparation processes. In this paper, titania (TiO2) was introduced into SiO2 matrix to form photocatalytic hybrid gels. The TiO2/SiO2 composites were then reinforced by the impregnation of various fibrillary reinforcements, such as glass, mullite mineral and ceramic fibers. The properties of the composites were studied systematically in terms of fiberstability, microstructure, chemical interaction and thermal conductivity. The final xerogel composites displayed improved monolithic geometry, satisfied thermal conductivity (0.09 -0.25 W . m-1 . K -1) and optimized photocatalytic performance (85 % removal of model pollutant of methyl orange (Mo)) , which could be expected to be a feasible route to multi-functional building facades in the future. [ABSTRACT FROM AUTHOR]

Metal oxide aerogels, inorganic cousins of the highly commercialized metalloid oxide silica aerogels, exhibit distinct properties specific to each type. Nevertheless, they share a common challenge with silica aerogels—brittleness and low mechanical strength due to their particulate necklace‐like structure. In contrast, polymer aerogels often boast significantly enhanced mechanical properties thanks to their nanofibrillated networks. To enhance the mechanical properties of metal oxide aerogels, the metal oxide formation with a polymeric nanostructure is micro‐templated. This method transforms the necklace‐like particulate microstructure of metal oxide aerogels (e.g., Al2O3 Cr2O3, and Fe2O3) into a polymer‐like nanobelt structure. Remarkably, even after removing the polymer template through calcination at 600 °C, the nanobelt structure remains intact. These metal oxide nanobelt (MNB) aerogels exhibit exceptional compressibility while retaining their mesoporous structure. As a demonstration, the resulting Al‐MNB aerogel can withstand compression up to 80% strain without fracturing while preserving its porous nanobelt structure and a high specific surface area of 228 m2 g−1 and a pore volume of 0.7 cm3 g−1 after heat treatment at 1300 °C. This work introduces an innovative strategy for creating a distinctive polymer‐like nanobelt microstructure, paving the way for novel applications of metal oxide aerogels with unique structures and enhanced performance. [ABSTRACT FROM AUTHOR]

Mitigating embodied emissions is becoming increasingly crucial as the energy supply shifts toward more sustainable sources. Bio-based materials present a potentially more sustainable alternative to synthetic polymers; however, it often do not yet match the performance of synthetic materials. Given the ongoing reliance on high-performance, high-environmental-impact materials, it is essential to ensure their complete recyclability. Aerogels, recognized by IUPAC as one of the top ten emerging technologies, are witnessing rapid market growth in thermal insulation and thermal protection applications. In certain applications, synthetic and composite aerogels exhibit superior performance, particularly under high temperatures. Here, molecular simulation tools are employed to elucidate the interaction forces between polymers and solvents, develop a recycling strategy for polyimide-based aerogels, and demonstrate their application in thermal protection for firefighter textiles and thermal runaway protection for Li-ion battery packs. These composites are engineered for disassembly, allowing for the complete recovery of starting materials without any degradation of components after multiple recycling cycles. The recyclable composites can be fabricated using various manufacturing techniques to produce fibers (1D), membranes (2D), and complex structures (3D). This unique combination of outstanding performance and excellent recyclability facilitates the sustainable utilization of aerogels in protective clothing, electric mobility, consumer goods, and aeronautics., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Objective: To explore the role of prenatal exposure to lipopolysaccharides (LPS) on aortic morphology in the neonatal offspring rats., Methods: Twelve pregnant rats were randomly divided into three groups: control group, LPS group, and PDTC (pyrrolidinedithiocarbamate, LPS+PDTC) group. The rats were intraperitoneally administered vehicle, LPS (0.79 mg/kg) , or LPS plus PDTC (100 mg/kg) , respectively. LPS was given on the 8th, 10th and 12th days, whereas vehicle and PDTC were given daily from the 8th to the 14th day during gestation. Histopathological alteration of the thoracic aorta was observed by hematoxylin-eosin staining and transmission electron microscopy, thoracic aortic mRNA and protein expression of connexin (Cx) molecules including Cx37, Cx40, Cx43 and Cx45 in offspring was detected by Real Time PCR and confocal laser-scanning microscope, respectively, offspring body weight was measure at day 1 and week 1., Results: Body weight at 1 day and 1 week-old offspring was significantly lower in LPS group than in control group (P < 0.01), which were significantly higher in PDTC group compared to LPS group (P < 0.01): [1 day: control group (7.425 ± 0.146) g, LPS group (6.742 ± 0.128) g, PDTC group (7.137 ± 0.141) g; 1 week: control group (20.173 ± 3.982) g, LPS group (13.264 ± 2.581) g, PDTC group (17.863 ± 3.412) g]. In 1 week-old offspring of LPS group, the thoracic aortas exhibited lesions, including impaired endothelial cells, thickening and fibrous changes of intimae, and migration and proliferation of vascular smooth muscle cells; the number of gap junction was decreased versus control group and pathological changes were similar between PDTC group and LPS group. Cx43 protein expression in LPS group was obviously lower than in control group and which could be partly reversed in PDTC group. Expression of Cx43 mRNA was significantly lower in 1 day and 1 week offspring of LPS group compared to control group (P < 0.05), which could be reversed in PDTC group (P < 0.05) (1 day: control group 1.530 ± 0.296, LPS group 1.226 ± 0.209, PDTC group 1.619 ± 0.324; 1 week: control group 9.357 ± 1.917, LPS group 7.204 ± 1.165, PDTC group 9.271 ± 1.514)., Conclusion: Our results indicate that maternal LPS exposure during pregnancy leads to vascular changes in neonatal offspring which might increase the susceptibility to adult hypertension.