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161.
In this work, environmentally friendly magnetite nanoparticles (Fe3O4 MNPs) were used to adsorb chlorotetracycline (CTC) from aqueous media. Fe3O4 MNPs exhibit ultrahigh adsorption ability to this widely used antibiotic. The adsorption behavior of CTC on Fe3O4 MNPs fitted the pseudo-second-order kinetics model, and the adsorption equilibrium was achieved within 10 h. The maximum Langmuir adsorption capacity of CTC on Fe3O4 (476 mg g−1) was obtained at pH 6.5. Thermodynamic parameters calculated from the adsorption data at different temperature showed that the adsorption reaction was endothermic and spontaneous. Low concentration of NaCl and foreign divalent cations hardly affected the adsorption. Negative effect of coexisting humic acid (HA) on CTC adsorption was also observed when the concentration of HA was lower than 20 mg L−1. But high concentration of HA (>20 mg L−1) increased the CTC adsorption on Fe3O4 MNPs. The matrix effect of several environmental water samples on CTC adsorption was not evident. Fe3O4 MNPs were regenerated by treatment with H2O2 or calcination at 400 °C in N2 atmosphere after separation from water solution by an external magnet. This research provided a high efficient and reusable adsorbent to remove CTC selectively from aqueous media. 相似文献
162.
本文重点研究了三级安全等级保护的基本模型和基本技术、设计思路,并指出了建设过程应该关注的几个关键问题。最后简单介绍了等保系统存在的安全风险。以期能对等级保护建设时提供参考。 相似文献
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Shunlin Zhang Yuxin Xie Rosie J. Somerville Farzaneh Fadaei Tirani Rosario Scopelliti Zhaofu Fei Dunru Zhu Paul J. Dyson 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(41):2206999
Solid-state proton conductors based on the use of metal–organic framework (MOF) materials as proton exchange membranes are being investigated as alternatives to the current state of the art. This study reports a new family of proton conductors based on MIL-101 and protic ionic liquid polymers (PILPs) containing different anions. By first installing protic ionic liquid (PIL) monomers inside the hierarchical pores of a highly stable MOF, MIL-101, then carrying out polymerization in situ, a series of PILP@MIL-101 composites was synthesized. The resulting PILP@MIL-101 composites not only maintain the nanoporous cavities and water stability of MIL-101, but the intertwined PILPs provide a number of opportunities for much-improved proton transport compared to MIL-101. The PILP@MIL-101 composite with HSO4− anions shows superprotonic conductivity (6.3 × 10−2 S cm−1) at 85 °C and 98% relative humidity. The mechanism of proton conduction is proposed. In addition, the structures of the PIL monomers were determined by single crystal X-ray analysis, which reveals many strong hydrogen bonding interactions with O/N H···O distances below 2.6 Å. 相似文献