Chemical structures bearing a combination of aggregation-induced emission enhancement (AIEE) and intramolecular charge transfer (ICT) properties attracted the attention of many researchers. Recently, there is an increasing demand to pose tunable AIEE and ICT fluorophores that could present their conformation changes-related emission colors by adjusting the medium polarity. In this study, we designed and synthesized a series of 4-alkoxyphenyl-substituted 1,8-naphthalic anhydride derivatives NAxC using the Suzuki coupling reaction to construct donor–acceptor (D-A)-type fluorophores with alkoxyl substituents of varying carbon chain lengths (x = 1, 2, 4, 6, 12 in NAxC). To explain the observation that molecules with longer carbon chains revealed unusual fluorescence enhancement in water, we study the optical properties and evaluate their locally excited (LE) and ICT states by solvent effects combined with Lippert–Mataga plots. Then, we explored the self-assembly abilities of these molecules in water-organic (W/O) mixed solutions and observed the morphology of its nanostructure using a fluorescence microscope and SEM. The results show that NAxC, x = 4, 6, 12 show different degrees of self-assembly behaviors and corresponding aggregation-induced emission enhancement (AIEE) progresses. At the same time, different nanostructures and corresponding spectral changes can be obtained by adjusting the water ratio in the mixed solution. That is, NAxC compounds present different transitions between LE, ICT and AIEE based on the polarity, water ratio and time changes. We designed NAxC as the structure–activity relationship (SAR) of the surfactant to demonstrate that AIEE comes from the formation of micelle-like nanoaggregates, which causes a restriction of the transfer from the LE state to the ICT state, and micelle formation results in a blue-shift in emission and enhances the intensity in the aggregate state. Among them, NA12C is most likely to form micelles and the most obvious fluorescence enhancement, which will switch over time due to the nano-aggregation transition.
In this work, methods for preparing alumina-titania and ceria-titania mixed oxide supports were studied. In one method, alumina or ceria were precipitated on the surface of a commercial titanium oxide,. In the second method, alumina or ceria were impregnated on the surface of titania followed by drying and calcination as with the first method .The metal oxide couples used in this study contains NiO and MoO 3 . In this study,the catalyst content of NiO is3 wt% while MoO 3 is8 wt.% while 89 wt.% is the support material. Surface area and pore volume measurements for the supports and catalysts were determined. Al, Ce, Ni and Mo contents as well as the coke percentage the spent catalyst were determined by chemical analysis. Characterization of the prepared support samples have been studied by DTA and XRD. The HDS activities of the prepared catalyst samples have been studied in comparison with titania and alumina catalysts. Two types of catalytic tests were used.One type of measurement was a screening test using the pulse technique while the second type was focused on studying the effect of important process variables as reaction temperature, hydrogen pressure and liquid hourly space velocity (LHSV) on the extent of HDS of gas oil (GO) feadstock and simultaneous HDS and HDN of GO + Pyridine on the selected screened catalysts by using the continuous flow highpressure fixed bed cata -test unit. The results revealed that these catalysts are much more active than the conventional NiMo/Al 2 O 3 catalysts on HDS and HDN reactions. The results revealed that these catalysts are much more active than the conventional NiMo/Al 2 O 3 catalysts on HDS and HDN reactions.They also demonstrate high aromatic saturation capabilities. The inhibiting effect of pyridine on gas oil HDS was found to be similar for all catalysts, i.e.: was independent on the support composition.In general, diesel fuel quality improved as the temperature and pressure increased or space velocity decreased.
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