Structural Chemistry - The molecular mechanism of the cycloaddition reactions of 2H-azirine with 1-methoxybutadiene and cyclohexadiene has been studied at the M06-2X/cc-pVDZ level of theory.... 相似文献
Journal of Solid State Electrochemistry - Nanostructured carbon material (NSCM) based chemiresistive sensors are popular for sensing different analytes because of their high sensitivity, low cost,... 相似文献
Benzofurocarbazole moieties are commonly used donor structures in the design of thermally activated delayed fluorescence (TADF) emitters. However, only 5 H-benzofuro[3,2-c]carbazole (34BFCz) has been reported and, to the best of our knowledge, no other benzofurocarbazole derivatives have been covered in the literature. In the present study, two further benzofurocarbazole moieties, 12 H-benzofuro[3,2-a]carbazole (12BFCz) and 7 H-benzofuro[2,3-b]carbazole (23BFCz), have been synthesized to investigate the effect of the donor structure on the photophysics and device parameters of TADF emitters. Two benzofurocarbazole-derived TADF emitters, 12-(2-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-12 H-benzofuro[3,2-a]carbazole (o12BFCzTrz) and 7-(2-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-7 H-benzofuro[2,3-b]carbazole (o23BFCzTrz), have been compared with 5-(2-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-5 H-benzofuro[3,2-c]carbazole (oBFCzTrz). The benzofurocarbazole donor structure governs the TADF characteristics, such as charge-transfer property and emission color. The 12BFCz donor has proved to be effective in blue-shifting the emission color, and 34BFCz has proven useful for improving the external quantum efficiency (EQE). The 12BFCz-derived o12BFCzTrz showed blue-shifted color coordinates of (0.159, 0.288), compared to (0.178, 0388) for o23BFCzTrz and (0.169, 0.341) for oBFCzTrz. The 34BFCz-derived oBFCzTrz exhibited an EQE of 22.9 %, compared to 19.2 % for o12BFCzTrz and 21.1 % for o23BFCzTrz. 相似文献
The main aim of this paper was to study the effect of a new tripodal chelating agent on La1?xSrxCo1?yFeyO3?δ perovskite prepared by the complexation method. For this purpose, a phenolic derivative of glycine (L) was synthesized applying the Mannich reaction and characterized by NMR and IR spectroscopies as well as by elemental analysis. To evaluate the complexation capability of L, its formation constants with the perovskite cations were measured. Comparison of these results with those reported for the complexaion with glycine, introduced L as a good candidate for the complexation with Fe(III) and La(III) cations. Furthermore, the powder XRD observations confirmed an improvement in the perovskite formation in the presence of L. 相似文献
A magnetic sorbent was fabricated by coating the magnetized graphene oxide with polystyrene (PS) to obtain a sorbent of the type GO-Fe3O4@PS. The chemical composition and morphology of the sorbent were characterized. The sorbent was employed for the enrichment of polycyclic aromatic hydrocarbons (PAHs) from water samples. Various parameters affecting the enrichment were investigated. The PAHs were then quantified by gas chromatography with flame ionization detection. Linear responses were found in the range of 0.03–100 ng mL?1 for naphthalene and 2-methylnaphthalene, and of 0.01–100 ng mL?1 for fluorene and anthracene. The detection limits (at an S/N ratio of 3) range between 3 and 10 pg mL?1. The relative standard deviations (RSDs) for five replicates at three concentration levels (0.05, 5 and 50 ng mL?1) of analytes ranged from 4.9 to 7.4%. The method was applied to the analysis of spiked real water samples. Relative recoveries are between 95.8 and 99.5%, and RSD% are <8.4%.
Graphical abstract A magnetic sorbent was fabricated by polystyrene coated on the magnetic graphene oxide for the extraction and preconcentration of PAHs in water samples prior to their determination by gas chromatography with flame ionization detection.
A new method for multi-component synthesis of 1,4-dihydropyridine derivatives (1,4-DHPs) in the presence of meglumine supported on multiwalled carbon nanotubes (MWCNTs@meglumine) as a new heterogeneous, highly efficient and reusable catalyst was investigated. The reaction was performed under ultrasonic irradiation in EtOH at room temperature. A new, highly efficient heterogeneous catalyst, short reaction times, high to excellent yield of products, and safe and clean conditions are the advantages of the presented method. 相似文献
A method for one-step synthesis of ultrafine agarose-coated superparamagnetic iron oxide nanoparticles (AC-SPIONs) was developed. The method is facile and fast and requires no organic solvent or surfactant. The average particle size of the prepared AC-SPIONs was only 20–40 nm with a narrow size distribution and with large saturation magnetization at room temperature. The obtained ultrafine nanogel particles were characterized by scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, transmission electron microscopy and vibrating sample magnetometer techniques. The AC-SPIONs were epoxy-activated by epichlorohydrin and aminated by ammonium hydroxide. The amination of the particles was investigated by the Kaiser test. The adsorption of two model compounds (gallic acid and ellagic acid) on the functionalized nanoparticles and their releases from them were investigated spectrophotometrically in three different pH values under biological conditions. The functionalized AC-SPIONs displayed good adsorption and in vitro drug release in a phosphate-buffered saline (pH 7.4). The ultrafine AC-SPIONs can be potentially used in magnetic solid-phase extraction, drug delivery, protein purification and enzyme immobilization methods. 相似文献