Water-stable metal−organic framework (MOF) UiO-66 was studied in boron removal from water for the first time. XRD, SEM, nitrogen adsorption/desorption isotherms, and thermogravimetric analysis (TG) were employed to confirm the structure. The boron adsorption kinetics, isotherms, thermodynamics, mechanism, and recycling on UiO-66 were further investigated in batch adsorption process. UiO-66 exhibits great adsorption performance of 10.59 mmol• g −1 at 45 °C, and the adsorption process reaches equilibrium rapidly in 1 h. Pseudo-second-order model, intraparticle diffusion, and Boyd model are employed for kinetic analysis. The process is a spontaneous endothermic process controlled by entropy change rather than enthalpy change, which suggests intensive chemisorption. The adsorption capacity does not decrease obviously after four cycles. Characterization on exhausted UiO-66 with 11 B MAS NMR reveals not solely interaction between boric acid and UiO-66. The XPS patterns suggest interaction with an Zr site, which is confirmed by the adsorption simulation with quantum chemistry. Higher boron adsorption capacity than conventional boron removal adsorbents and easy regeneration make UiO-66 a promising agent for boron removal from aqueous solution.

A two-section temperature strategy was employed to achieve micromesoporous composites with five kinds of long-chain alkyl quaternary ammonium salts as single template. Zeolites with an ordered twodimensional hexagonal mesopore and crystallized MFI domain were successfully obtained. Gemini quaternary ammonium salt surfactants C 18 N 2 and C 22 N 2 are effective in directing the structure of MCM-41 than CTAB at 100 °C and will transform to lamellar MFI structures at 150 °C gradually. While single quaternary ammonium salts C 18 N and C 22 N direct lamellar M41s at 100 °C and transform to mesoporous structure at a higher temperature of 150 °C, it is possible to get a composite of microporous and mesoporous material with a surface area as high as 1046 m 2 g −1 . Catalytic performance of typical hierarchical zeolites was evaluated by Claisen-Schmidt condensation of bulky reactants. The excellent conversion suggested the synergy effects of improved large molecule diffusion in mesopores and highly separated MFI domains as catalytic centers in the hierarchical zeolites, which can be explained by an appletree model.

The rapid development of IoT (Internet of Things) brings great convenience to people through the utilization of IoT applications, but also brings huge security challenges. Existing IoT security breaches show that many IoT devices have authentication flaws. Although many IoT authentication schemes were proposed, they are not fit for recent smart IoT applications covering IoT device, back-end sever, and user-end mobile applications. To build the first line of defense for smart IoT systems, this paper proposes a new authentication scheme. The proposed scheme first models the entire lifecycle of the IoT device authentication for real-world scenarios of smart IoT systems that contains factory manufacturing, daily usage, and system resetting. For each stage in the lifecycle, the proposed scheme employs efficient symmetric key mechanisms to achieve the authentication between IoT device, back-end server, and mobile application. The proposed scheme supports both server-free local area network communication and sever-involved remote public area communication. Formal security verification shows that the proposed scheme resists existing attacks. The open-source experimental evaluations also show that the proposed scheme is efficient and promising for practical usage.

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