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401.
N-doped SWCNT with different concentration of doped nitrogen atoms were investigated through density functional theory (DFT) calculations for detecting CO molecule. The CO molecule was adsorbed to different sites of the modified nanotubes and their geometric structures and electronic properties were investigated after full optimization. A significant change can be observed in adsorption energies and electronic properties of N-doped SWCNT after CO adsorption. By increasing the number of nitrogen atoms in each unit cell, these properties change more obviously. So these modified nanotubes can be used as CO sensors.  相似文献   
402.
Abstract 3-[(Naphthalen-2-yl) methyl]isocoumarin was synthesized by the reaction of homophthalic acid with 2-(naphthalen-2-yl)acetyl chloride at elevated temperature and its crystal structure has been determined (C20H14O2), Mr = 286.31, a = 13.704(3), b = 7.356(4), c = 7.042(7) ?, β = 99.21(3)°, space group Pc, Z = 2, and V = 700.7(8) ?3. The isocoumarin and the naphthalene ring systems are individually planar and the dihedral angle between the mean planes of these two ring systems is 70.05(8)°. Graphical Abstract Synthesis and crystal structure of 3-[(Naphthalen-2-yl)methyl]isocoumarin Aamer Saeed, Junmei Liang, Masood Parvez The synthesis and crystal structure of a novel isocoumarin, 3-[(naphthalen-2-yl)methyl]isocoumarin has been presented.   相似文献   
403.
The occurrence of fungal infections has increased over the past two decades. It is observed that superficial fungal infections are treated by conventional dosage forms, which are incapable of treating deep infections due to the barrier activity possessed by the stratum corneum of the skin. This is why the need for a topical preparation with advanced penetration techniques has arisen. This research aimed to encapsulate fluconazole (FLZ) in a novasome in order to improve the topical delivery. The novasomes were prepared using the ethanol injection technique and characterized for percent entrapment efficiency (EE), particle size (PS), zeta potential (ZP), drug release, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and antifungal activity. The FN7 formulation with 94.45% EE, 110 nm PS and −24 ZP proved to be the best formulation. The FN7 formulation showed a 96% release of FLZ in 8 h. FTIR showed the compatibility of FLZ with excipients and DSC studies confirmed the thermal stability of FLZ in the developed formulation. The FN7 formulation showed superior inhibition of the growth of Candida albicans compared to the FLZ suspension using a resazurin reduction assay, suggesting high efficacy in inhibiting fungal growth.  相似文献   
404.
The objective of this study was to assess the biological potency and chemical composition of Rumex vesicarius aboveground parts using GC–MS. In this approach, 44 components were investigated, comprising 99.99% of the total volatile compounds. The major components were classified as fatty acids and lipids (51.36%), oxygenated hydrocarbons (33.59%), amines (7.35%), carbohydrates (6.06%), steroids (1.21%), and alkaloids (0.42%). The major components were interpreted as 1,3-dihydroxypropan-2-yl oleate (oxygenated hydrocarbons, 18.96%), ethyl 2-hydroxycyclohexane-1-carboxylate (ester of fatty acid, 17.56%), and 2-propyltetrahydro-2H-pyran-3-ol (oxygenated hydrocarbons, 11.18%). The DPPH antioxidant activity of the extracted components of R. vesicarius verified that the shoot extract was the most potent with IC50 = 28.89 mg/L, with the percentages of radical scavenging activity at 74.28% ± 3.51%. The extracted plant, on the other hand, showed substantial antibacterial activity against the diverse bacterial species, namely, Salmonella typhi (23.46 ± 1.69), Bacillus cereus (22.91 ± 0.96), E. coli (21.07 ± 0.80), and Staphylococcus aureus (17.83 ± 0.67). In addition, the extracted plant was in vitro assessed as a considerable anticancer agent on HepG2 cells, in which MTT, cell proliferation cycle, and DNA fragmentation assessments were applied on culture and treated cells. The larvicidal efficacy of the extracted plant was also evaluated against Aedes aegypti, the dengue disease vector. As a result, we may infer that R. vesicarius extract increased cytocompatibility and cell migratory capabilities, and that it may be effective in mosquito control without causing harm.  相似文献   
405.
The newly discovered crystal structures of CH3(OCH2CH2)OCH3(LiCF3SO3)2, monoglyme:(LiTf)2, and CH3(OCH2CH2)3OCH3(LiCF3SO3)2, triglyme:(LiTf)2, are briefly described. The coordination of lithium cations and the CF3SO3 anions in these structures is compared with the cation and anion coordination in the crystalline phase of high molecular weight P(EO)3LiCF3SO3. Comparison is also made with the previously reported crystalline phase of CH3(OCH2CH2)2OCH3LiCF3SO3, diglyme:LiTf. A tendency to form trans-gauche-trans conformations for the bond order -O-C-C-O- is noted in adjacent ethylene oxide sequences interacting with a five-coordinate lithium ion.  相似文献   
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