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The effects of steaming at varying times and temperatures on ZSM-5 pore structures, framework Al distribution, acid properties and ethanol to propene (ETP) catalytic performance were systematically studied in this study. The results show that the crystallinity and specific surface areas of steam treated ZSM-5 samples decrease with the increase treatment time and temperature. 27Al MAS NMR and Co(II) exchange-ICP results show that the isolated framework Al species (Alsingle) can be preferentially removed from the zeolite framework, while the paired Al sites (Alpairs) remain relatively stable after steam treatment. The characterization of Py-IR reveals that the concentration of B acid sites and the acid strength are all declined with the steaming time or temperature increase. The catalytic results of ETP at 450°C show that the sample after steaming gives improved selectivities to propene and butene at the expense of ethene conversion and alkanes selectivity relative to the unmodified zeolite. Besides, a good positive correlation between ethylene conversion and Alsingle concentration is found, whereas the propene formation is influenced by the combination effect of Alsingle and Alpairs sites.

Taking advantage of a nitronyl nitroxide radical ligand 8-QNNIT (1) (8-quinolyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide) and Ln(hfac)3·2H2O (LnIII = Tb 2 and Dy 3; hfac = hexafluoroacetylacetonate), two Ln–radical one-dimensional chains [Ln(hfac)3(8-QNNIT)]n were constructed. The magnetic properties, thermodynamics and optical behavior of both compounds were observed, exhibiting polyfunctionality of the 2p–4f system. Complexes 2 and 3 show typical single-chain magnet (SCM) properties with temperature-dependent relaxation peaks giving an effective energy barrier (Ueff/kB) of 47.4 K (2) and 64.6 K (3). Luminescence spectra and ultravioletvisible (UV-vis) absorption spectra of the Tb compound, and UV-vis absorption spectra and thermodynamics properties of the Dy complex were investigated. As far as we know, the Dy complex is the first SCM with thermodynamics behavior and optical properties comparable to those of multifunctional magnetic materials. This study aims to provide a new way and field of vision for the construction of 2p–4f heterospin multi-functional materials.

A superhydrophobic and corrosion-resistant coating with hierarchical macro/nanostructures was constructed by one-step electrodeposition of dodecyltrimethoxysilane (e-DTMS) on Mg alloy AZ31 in a relatively media. The surface morphology and chemical composition were characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). Surface wettability was evaluated by measuring water contact angles and sliding angles of water droplets. The protective performance was measured by electrochemical and hydrogen evolution tests. The results indicated that the e-DTMS coating had excellent self-cleaning performance with a contact angle of 158° ± 2.3° and a sliding angle of 4° ± 0.5°. The superhydrophobic surface greatly reduced the contact area between the AZ31 substrate and water, and it was chemically stable in corrosive media. The corrosion current density (2.11 × 10−7 A cm−2) of the e-DTMS coating was about three hundred times less than that of the AZ31 substrate (7.34 × 10−5 A cm−2). The results demonstrated that the e-DTMS coating remarkably enhanced the anti-corrosion performance of AZ31 alloys.

A novel Ag3PO4/WO3·H2O composite was prepared by loading Ag3PO4 on WO3·H2O substrate via a two-step hydrothermal method and characterized by various analytical techniques. The photocatalytic performance was evaluated by the degradation of methylene blue (MB) and oxytetracycline (OTC) under visible light irradiation. Within 30 min, 98.9 % MB can be degraded by the Ag3PO4/WO3·H2O composite with a molar ratio of 3:1 (3Ag/1W), which is higher than that of individual Ag3PO4 and WO3·H2O. The 3Ag/1W photocatalyst also exhibits improved photocatalytic activity for OTC degradation than pure WO3·H2O and Ag3PO4. The improvement of photocatalytic activity would be mainly ascribed to the highly efficient separation of photo-induced electron-hole pairs due to matched band structure, as confirmed by photoluminescence spectra (PL) and photocurrent responses test. According to the experimental results of radical trapping and electron spin resonance (ESR), a possible photocatalytic mechanism of the Ag3PO4/WO3·H2O composite was proposed.

Superhydrophobic coatings can remarkably improve the anti-corrosion performance of many materials. In this study, a fluorine-free superhydrophobic Mg(OH)2/DTMS composite coating was successfully fabricated on the surface of Mg alloy AZ31 by hydrothermal process and electrodeposition of dodecyltrimethoxysilane to enhance corrosion resistance. The corrosion resistance of the coating was tested using a potentiodynamic polarization scan, electrochemical impedance spectroscopy (EIS), and hydrogen evolution measurements. The superhydrophobicity was investigated by measuring water contact angles and sliding angles. The results showed that the Mg(OH)2/DTMS composite coating was composed of walnut-like micro/nanostructures and exhibited superhydrophobicity with a contact angle of 165.1° ± 2.1° and a sliding angle of 3.5° ± 0.6°. Moreover, the corrosion current density of the composite coating (1.777 × 10−8 A·cm−2) decreased about three orders of magnitude compared with uncoated AZ31 substrate (7.342 × 10−5 A·cm−2), suggesting that the composite coating had excellent corrosion resistance. Finally, the anti-corrosion mechanism of the composite coating was also addressed.

The linear trienes were obtained in high yields by copper-mediated cycloaddition of 2,5-bis(trimethylsilyl)zirconacyclo-pentadienes with dimethyl acetylenedicarboxylate (DMAD) which can be quantitatively converted to novel asymmetric hexasubstituted cyclohexadienes with high (E)-stereoselectivity. The structure of cyclohexadienes was determined via X-ray analysis.