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Efforts to develop a green, inexpensive and effective adsorbent are crucial for eliminating antibiotics in polluted water. The sorption capacity of the as-prepared polyvinyl alcohol (PVA)-assisted cellulose nanocrystals/SiO 2 (CNCs/SiO 2 ) composite aerogel to ciprofloxacin (CIP) rises with the increase of temperature and initial concentration. Reverse trend of sorption capacity can be found when increasing the adsorbent dosage of adsorbent. The optimal pH value for the sorption is proved to be 4. It's found in the uniaxial compression test that the maximum load that PVA-assisted aerogels can withstand is nearly 100 times than that of non-PVA aerogels. Sorption results confirm that the Pseudo-second order (R 2  = 0.9885) and Langmuir models (R 2  = 0.9959) fit well to sorption kinetics and equilibrium data, respectively. The rate constant differs from the initial concentration of CIP according to the Pseudo-second order model. The composite aerogel sorption capacity of Langmuir (q max ) for CIP was 163.34 mg·g -1 . The thermodynamic studies showed that the sorption process is endothermic with the value of enthalpy change of 41.032 kJ/mol. Hydrogen bonding, π-π interaction, hydrophobic and electrostatic interactions are the dominant mechanisms of CIP sorption by the PVA-assisted CNCs/SiO 2 composite aerogel., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Micron-sized hydrophobic SiO 2 encapsulated SiO 2 gel (HSESG) was prepared successfully by using SiO 2 gel as the solid core and hydrophobic nano-SiO 2 particle as the shell under high-speed shear stirring. The flowability, stability, particle size distribution, bulk density and water repellency of the powder were measured separately, and it was concluded that this type of product can exhibit smaller static angle, larger flow rate and lower bulk density. After the formation of a stable spatial network of SiO 2 gel in its interior, relevant fire extinguishing experiments were carried out and HSESG exhibits higher efficiency in suppressing wood stack fires than that of ordinary dry water (DW) and ABC dry powder. As a high-efficiency fire-extinguishing material, it also exhibits excellent environmental friendliness and non-toxicity, which will make it have the potential to develop a new application market., (Copyright © 2020 Elsevier B.V. All rights reserved.)