Search

A series of novel imidazo[4,5-b]pyridine derivatives were synthesized and their structures were characterized by NMR spectroscopy, mass spectrometry and elemental analysis. The results of bioassays showed that some compounds exhibit good fungicidal activity against Puccinia polysora In particular, compound 7b showed an EC50 value of 4.00 mg/L, which was comparable with that of tebuconazole. Besides, preliminary structure-activity relationship was discussed.

The advanced oxidation process based on persulfate group is a promising technology for water purification. However, the synergistic effect of free radical and non‐free radical degradation is still not feasible in the persulfate activation process, which consumes a large amount of external energy. The self‐floating Cu3BiS3/polydopamine/polyurethane sponge was prepared using a simple method, resulting in high catalytic performance when activated by peroxydisulfate (PDS). The experiments conducted to identify free radicals showed that the degradation process of tetracycline (TC) involved the synergistic action of non‐radical 1O2 and free radicals (SO4⋅− and • OH) and the conversion of Cu+/Cu2+. The addition of Cl−, HCO3−, PO43−, and SO42− to the solution did not significantly affect the high degradation rate of TC. Furthermore, the interfacial evaporation process achieved a remarkable evaporation rate of 1.53 kg m−2 h−1 and produced reclaimed water without any detectable TC contaminants. The sponge also exhibited excellent salt resistance and chemical stability. This study provides valuable insights into the degradation of antibiotics and the desalination of seawater. [ABSTRACT FROM AUTHOR]

The YMnO3/TiO2 composite photocatalysts with high photocatalytic activity for the degradation of tetracycline hydrochloride have been synthesized successfully via a simple cryogenic route. The characterization of phase composition, purity and functional group information showed that YMnO3 and TiO2 were the main components of YMnO3/TiO2 composite photocatalysts. After the coupling of YMnO3 and TiO2, the average particle size decreased compared with YMnO3, but increased compared with TiO2. With the increase of YMnO3 content, the ultraviolet–visible (UV) absorption coefficient of YMnO3/TiO2 composite photocatalysts decreases, while the visible optical absorption coefficient increases. The photocatalytic activity of YMnO3/TiO2 composite photocatalysts also increased with the increasing of YMnO3 content. The capture experiment and photocatalysis mechanism analysis showed that the holes, hydroxyl radicals and superoxide radicals played an important role in the photocatalyst degradation of tetracycline hydrochloride under simulated solar irradiation by YMnO3/TiO2 composite photocatalysts. This simple synthesis technique will provide technical reference for the construction of other type I band arrangement heterojunction photocatalysts. [ABSTRACT FROM AUTHOR]

A novel CFCl2CF2Cl(R113)/H2 gas treatment process was proposed and successfully applied for the redispersion of a sintered alloy PdCu/AC catalyst. The redispersion process was initiated by the formation of an oxidative PdCuClx intermediate, which can easily migrate to a nearby catalyst surface and then be reduced to smaller PdCu NPs. [ABSTRACT FROM AUTHOR]

A series of novel imidazo[4,5‐b]pyridine derivatives were designed and synthesized. The structures of all the newly synthesized compounds were identified by spectroscopic data NMR, MS, and elemental analysis. Bioassay showed that the compounds exhibited potent fungicidal activities against Erysiphe graminis, Puccinia polysora, and so forth. Particularly, 2‐chloro‐5‐((5‐methoxy‐2‐(2‐(trifluoromethyl)phenyl)‐3H‐imidazo[4,5‐b]pyridin‐3‐yl)methyl)thiazole (9b) displayed fungicidal potency against P. polysora. Its EC50 value: 4.00 mg/L is comparable with that of tebuconazole. The structure–activity relationship for the target compounds is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Using multi-walled carbon nano-tubes (MWNTs) as the template, Gd3+-doped mesoporous TiO2 (M-TiO2) material was prepared by the homogeneous precipitation-assisted template method. The as-prepared photo-catalysts were characterised using X-ray diffraction, scanning electron microscopy, nitrogen adsorption/desorption and ultraviolet–visible (UV–vis) diffuse-reflection spectroscopy analyses. The photo-catalytic properties of Gd3+-doped M-TiO2 were primarily investigated by the photo-degradation of methyl orange under Xe-lamp irradiation and compared with those of pure M-TiO2 and the commercial photo-catalyst Degussa P25. The results showed that the as-synthesised samples were of anatase crystalline phase and had red shifts in their UV–vis patterns with different Gd3+-doping concentrations. Gd3+-adding at 0.12mol% could significantly enhance the photo-catalytic properties of the M-TiO2 material and the rate of photo-degradation of methyl orange reached 97.3% under Xe-lamp irradiation for 150min. [Copyright &y& Elsevier]

Abstract: Ordered porous TiO2 thin films were fabricated on conductive glass by using colloid crystal template of polystyrene (PS) spheres. Microstructural characterization by scanning electron microscopy techniques was carried out to explore the porous structural changes due to the PS templates which could be controlled by adjusting the drawing rate. Photovoltaic performance was measured and this revealed the effect of microstructural changes. The results showed that monolayer porous TiO2 films and multilayer porous TiO2 films could be successfully prepared. And multilayer porous TiO2 films provided large surface area for dye absorption to increase the efficiency of dye-sensitized solar cells (DSSCs) which were assembled by porous TiO2 films. [Copyright &y& Elsevier]

A novel CFCl 2 CF 2 Cl(R113)/H 2 gas treatment process was proposed and successfully applied for the redispersion of a sintered alloy PdCu/AC catalyst. The redispersion process was initiated by the formation of an oxidative PdCuCl x intermediate, which can easily migrate to a nearby catalyst surface and then be reduced to smaller PdCu NPs.

In this study, three different approaches, i.e. the sol-gel method, precipitation method and hard-template method, were applied to synthesize MgF 2 catalysts with improved stability towards the dehydrofluorination of hydrofluorocarbons (HFCs); the in situ XRD technique was employed to investigate the relationship between the calcination temperature and the crystallite size of precursors to determine optimal calcination temperature for the preparation of the MgF 2 catalysts. Moreover, the physicochemical properties of MgF 2 catalysts were examined via BET, XRD, EDS and TPD of NH 3 and compared. Undoubtedly, the application of different methods had a significant influence on the surface properties and catalytic performances of MgF 2 catalysts. The surface areas of the catalysts prepared by the precipitation method, sol-gel method and template method were 120, 215 and 304 m 2 g -1 , respectively, upon calcination at 200 °C. However, the surface area of the MgF 2 catalysts decreased significantly when the calcination temperatures of 300 and 350 °C were applied. The catalytic performance of these catalysts was evaluated via the dehydrofluorination of 1,1-difluoroethane (HFC-152a). The MgF 2 catalyst prepared by the precipitation method showed the lowest catalytic activity among all the MgF 2 catalysts. When the calcination temperature was above 300 °C, the MgF 2 catalysts prepared via the template method demonstrated the highest catalytic conversion rate with catalytic activity following the order: MgF 2 -T (template method) > MgF 2 -S (sol-gel method) > MgF 2 -P (precipitation method). The conversion rate generally agreed with the total amount of acid on the surface of the catalysts, which was measured by the NH 3 -TPD technique. The MgF 2 -T catalysts were further examined for the dehydrofluorination of HFC-152a for 600 hours, and a conversion rate greater than 45% was maintained, demonstrating superior long-term stability of these catalysts., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)