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11.
A magnetic cotton/polyester fabric with photocatalytic, sonocatalytic, antibacterial and antifungal activities was successfully prepared through in-situ sonosynthesis method under ultrasound irradiation. The process involved the oxidation of Fe2+ to Fe3+ via hydroxyl radicals generated through bubbles collapse in ultrasonic bath. The treated samples were analyzed by X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and vibrating sample magnetometry. Photocatalytic and sonocatalytic activities of magnetite treated fabrics were also evaluated toward Reactive Blue 2 decoloration under sunlight and ultrasound irradiation. Central composite design based on response surface methodology was applied to study the influence of iron precursor, pH and surfactant concentration to obtain appropriate amount for the best magnetism. Findings suggested the potential of one-pot sonochemical method to synthesize and fabricate Fe3O4 nanoparticles on cotton/polyester fabric possessing appropriate saturation magnetization, 95% antibacterial efficiency against Staphylococcus aureus and 99% antifungal effect against Candida albicans, 87% and 70% dye photocatalytic and sonocatalytic decoloration along with enhanced mechanical properties using only one iron rich precursor at low temperature. 相似文献
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环糊精包结作用下水溶液共聚合制备疏水改性阳离子聚丙烯酰胺及其絮凝效果研究 总被引:1,自引:0,他引:1
在水溶液中制备了甲基环糊精(Me-β-CD)/疏水单体2-苯氧乙基丙烯酸酯(POEA)的包结物(1a)。利用紫外-可见光谱及核磁共振波谱等检测手段研究了Me-β-CD与POEA的包合作用,并对包合物的结构、性能进行了表征和分析。同时在水溶液中引发丙烯酰胺(AM)、阳离子单体丙烯酰氧乙基三甲基氯化铵(DAC)以及1a的均相共聚合得到疏水修饰的阳离子聚丙烯酰胺P(AM-DAC-POEA),实现了用绿色方法合成高效高分子絮凝剂的目的,并对该高分子对高岭土模拟污水的絮凝效果进行了考察。 相似文献
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Ligands N,N'-tetramethylthiourea and 2-mercapto-1-methyl-imidazole form stable Au(III) complexes [AuCl3(N,N'-tetramethylthiourea)] (1) and [AuCl3(2-mercapto-1-methyl-imidazole)] (2) instead of reducing the Au(III) metal center into Au(I), which would be typical for the attachment of sulfur donors. Compounds 1 and 2 were characterized by spectroscopic methods and by X-ray crystallography. The spectroscopic details were explained by simulation of the UV-Vis spectra via the TD-DFT method. Additionally, computational DFT studies were performed in order to find the reason for the unusual oxidation state in the crystalline materials. The preference for Au(III) can be explained via various weak intra- and intermolecular interactions present in the solid state structures. The nature of the interactions was further investigated by topological charge density analysis via the QTAIM method. 相似文献
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《中国化学快报》2021,32(9):2869-2872
Pressure-related sensing materials in mechanochromic luminescent materials have received wide attention. However, at present, most piezochromic luminescence (PCL) materials have problems such as aggregation-caused quenching (ACQ) effect due to the presence of powder form, complicated preparation methods and fluorescence quenching effect under high pressure. To solve these problems, we employ three components containing carbon dots (CDs), layered double hydroxides (LDHs) and polyvinyl alcohol (PVA) to construct the CDs-LDHs/PVA film. The LDHs can provide a rigid environment for CDs and improve the luminescent efficiency of CDs. The film shows high sensitivity, stability and reversibility. Moreover, the compressed film can recover to its original state by heating. Therefore, the PCL film with dual emission (fluorescence and phosphorescence) characteristic is constructed, which boosts the sensitivity of pressure-sensing. 相似文献
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A solvable cover of a graph is a regular cover whose covering transformation group is solvable. In this paper, we show that a solvable cover of a graph can be decomposed into layers of abelian covers, and also, a lift of a given automorphism of the base graph of a solvable cover can be decomposed into layers of lifts of the automorphism in the layers of the abelian covers. This procedure is applied to classify metacyclic covers of the tetrahedron branched at face-centers. 相似文献
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Several reference priors and a general form of matching priors are derived for a stress–strength system, and it is concluded that none of the reference priors is a matching prior. The study shows that the matching prior performs better than Jeffreys prior and reference priors in meeting the target coverage probabilities. 相似文献
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