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The development of new composite materials is of great significance to improve the photocatalytic degradation efficiency. In this article, the TiO2/ZIF‐8 composite materials (TZCM) have been designed via the combination of hydrothermal‐assisted liquid phase deposition and the simple coprecipitation method. The experimental results indicate that the TiO2 and ZIF‐8 nanoparticles can be tightly bonded together by chemical bonds. Moreover, the TZCM also exhibit a significantly increased specific surface area and a reduced band gap width, which would provide more active sites and realize the visible‐light response during the photocatalytic process. The photodegradation rate and the corresponding first‐order reaction rate of methylene blue within 24 min by TiO2/ZIF‐8 composite material (e.g., sample TZCM‐3) is 93.36% and 0.1376 min−1, which is 31 times and 17 times that of pristine TiO2 and ZIF‐8, respectively. According to the photoelectrochemical experiments, the separation efficiency of photogenerated electrons and holes in TZCM sample during the photocatalytic process could be significantly enhanced. [ABSTRACT FROM AUTHOR]

On the basis of an analysis of status quo and problems facing the travel development of Liaoxi Corridor, some developmental strategies with special characteristics are put forward to maintain the healthy development of the travel in Liaoxi Corridor, such as balancing the layout, building elite brands, strengthening local cooperation, etc. The purpose of the strategies is to increasingly improve the Corridor's competitiveness in tourism industry, and to achieve a balanced development in the local economy. The research results will be beneficial to the optimal layout for the travel in Liaoxi Corridor, and also to the improvement of competitiveness in travel for other regions in Liaoning Province. Meanwhile, the results also serve as a reference for the tourism of areas outside Liaoning Province. [ABSTRACT FROM AUTHOR]

A series of T- and H-shaped donor-acceptor (D-A) types of dipyrido[3,2- a:2′,3′- c]phenazine (DPPZ)-based molecules, extended by thienyl and triphenylamino chromophores at the 2,7-(bottom) and/or 10,13-positions (top), have been designed and prepared successfully. Synthetic, structural, thermal, spectral, and computational comparisons have been carried out for related compounds because of their adjustable intramolecular charge-transfer properties. It is noted that a pair of structural isomers ( 5 and 6) has been obtained, respectively, where distinguishable UV/Vis and fluorescence spectra, electrochemical activity, thermal stability, and bandgaps are observed. Furthermore, compounds 6, 8, 10, 11, 13, and 15 exhibit excellent thermal stability, and the Td10 values for them are found to range from 524 to 646 °C, which can be regarded as one of the best groups of thermally stable compounds among organic small molecules. In addition, theoretical calculations were performed, and the structure-property relationships were examined to reveal the effects of the position and number of donor arms on the DPPZ acceptor core. [ABSTRACT FROM AUTHOR]

A family of planar oligothiophene/imidazole/1,10-phenanthroline (OTIP)-based heterocyclic, aromatic, semiconducting, and fluorescent compounds with N-substituted alkyl chains (allyl, n-butyl, n-octyl, n-dodecyl, and n-cetyl) have been designed and synthesized. They all have specific N-coordination sites, various donor-acceptor spacers, good molecular planarity, suitable solubility, and high thermal stability. In comparison with conventional double β-alkylation of the thiophene ring, our results reveal that the single imidazole N-alkylation strategy for OTIPs has the advantage of maintaining the planarity of the whole molecule, in addition to improving the solubility, which can be clearly verified by the small dihedral angles between adjacent thiophene/imidazole/1,10-phenanthroline (TIP) rings in eight X-ray single-crystal structures. In particular, n-dodecyl- and n-cetyl-substituted OTIPs (7 and 8) with the same molecular length of 2.37 nm (MW =939 and 1052), show good molecular planarity with the aforementioned dihedral angles of 8.9(5) and 10.4(5)°. Furthermore, special attention has been paid to the physicochemical properties of seven symmetrical OTIPs (6-8, 13-15, and 19), including two to six thiophene rings in the middle of their molecular structures. To the best of our knowledge, this is the first synthetic, structural, and spectral investigation into the N-alkylation of OTIP-based compounds., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of T- and H-shaped donor-acceptor (D-A) types of dipyrido[3,2-a:2',3'-c]phenazine (DPPZ)-based molecules, extended by thienyl and triphenylamino chromophores at the 2,7-(bottom) and/or 10,13-positions (top), have been designed and prepared successfully. Synthetic, structural, thermal, spectral, and computational comparisons have been carried out for related compounds because of their adjustable intramolecular charge-transfer properties. It is noted that a pair of structural isomers (5 and 6) has been obtained, respectively, where distinguishable UV/Vis and fluorescence spectra, electrochemical activity, thermal stability, and bandgaps are observed. Furthermore, compounds 6, 8, 10, 11, 13, and 15 exhibit excellent thermal stability, and the Td10 values for them are found to range from 524 to 646 °C, which can be regarded as one of the best groups of thermally stable compounds among organic small molecules. In addition, theoretical calculations were performed, and the structure-property relationships were examined to reveal the effects of the position and number of donor arms on the DPPZ acceptor core., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A family of linear asymmetrical D-π-A and symmetrical D-π-D types of thiazole-based aromatic heterocyclic fluorescent compounds bearing various electron-donating and electron-withdrawing tails (bromo, triphenylamino, pyridyl, thienyl and benzoic acid) have been designed and prepared successfully. Synthetic, structural, thermal, spectral and computational comparisons have been carried out for related compounds because of their adjustable electronic properties. It is interesting to mention that compound 2 can be prepared from 5-bromothiazole by one-pot Suzuki-Miyaura coupling and subsequent C-H activation reactions via a 5-TPA-substituted thiazole intermediate 1. X-ray single-crystal structures of six compounds indicate that they all crystallize in the triclinic P1 space group and the thiazole core exhibits different dihedral angles with its adjacent benzene ring of the triphenylamino group (3.6(3)-40.8(3)°). The photophysical and electrochemical results demonstrate that compound 7 exhibits high electrochemical activity with a green fluorescence emission. Meanwhile, compounds 1, 2, and 6 show high luminescence quantum yields, and compound 8 exhibits excellent thermal stability (T(d(10)) = 503 °C).