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1.
《Advanced Powder Technology》2020,31(12):4585-4597
Focussing on visible light active ferrites for high performance removal of noxious pollutants, we report the synthesis of Mg0.5NixZn0.5-xFe2O4 (x = 0.1, 0.2, 0.3, 0.4, & 0.5) ferrite nanoparticle for degradation of reactive blue-19 (RB-19). Lattice parameters calculated using intense X-ray diffraction (XRD) peaks and Nelson-Riley plots (N-R plot) are in well agreement with each other. The sample Mg0.5Ni0.4Zn0.1Fe2O4 (M5N4) exhibits best performance with 99.5% RB-19 degradation in 90 min under visible light. Photoluminescence (PL) results confirm that recombination of charge carriers is highly reduced in the photocatalyst. Scavenging experiments suggest that O2− radicals were the dominant species responsible for photocatalytic performance. The photocatalytic mechanism was explained in terms of dopant driven shifting of conduction bands and valence bands (calculated by Mott-Schottky plots). The thermodynamic probability of radical generation along with role of redox cycles of metal ions has been discussed in the mechanism. The dye degradation was ascertained by detection of intermediates via mass spectrometry analysis and a possible degradation route was also predicted. The findings in this work provide intriguing opportunities to modify the electronic band structure of spinel ferrites for visible and solar light photocatalytic activity for environmental detoxification. 相似文献
2.
John Bensted 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(4):181-184
Characterisation of raw materials for Portland cement manufacture by use of the methylene blue adsorption method is discussed. The method is shown to be a simple, convenient ‘rule of thumb’ procedure. It provides a guide to the quantity and type of argillaceous minerals present in a given raw material sample. 相似文献
3.
Qin‐Tao Liu Malcolm R Clench Judith L Kinderlerer 《Journal of the science of food and agriculture》2002,82(5):553-558
Structural isomers of monoacylglycerols (monoglycerides, MAGs) were identified and compared after degradation of butter oil by two strains of Penicillium roquefortii and a commercial lipase from P roquefortii (EC 3.1.1.3) at pH 7.0 and 10 °C. The conditions were selected as they were comparable with those used in the manufacture of blue mould‐ripened cheese. The commercial lipase was selected to compare with the fungal strains in terms of acyl migration. Results showed that the main isomers formed by lipolysis with the commercial lipase were sn‐2 MAGs (64 mol%), whilst spores and emerging mycelia of P roquefortii produced mainly sn‐1(3) MAGs (83–90 mol%). The work reported here may lead to further assessment of different MAG structural isomers as natural preservatives in foods and dairy products. © 2002 Society of Chemical Industry 相似文献
4.
Comments on the article "A house divided? The psychology of red and blue America" by D. C. Seyle and M. L. Newman (see record 2006-11202-001). Seyle and Newman concluded that the red and blue metaphor is inaccurate and proposed a purple America strategy to better convey that the majority of people do not align themselves with political extremes. There is interdisciplinary agreement on this. Although not cited by Seyle and Newman, the findings by Professor Fiorina of Stanford University were reported by the APA Monitor on Psychology in its coverage of the 2005 APA State Leadership Conference (Murray Law, 2005). In contrast to their social psychological analysis, Seyle and Newman were incorrect in concluding that "[a]s psychologists, we are not in a position to change either the elements of the American political system that may spur this conflict or even the decisions made by pundits, politicians, and reporters about the terms they choose to use in political discussion" (p. 579). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
现代民间青花与现代陶艺 总被引:1,自引:0,他引:1
现代民间青花与现代陶艺都是火与土的艺术,都具有粗犷,质朴、自然、大方的共同艺术特点。前者在传统民间青花的基础上,汲取了现代陶瓷科技成就和现代文化艺术成果,而发展成为富有现代艺术意蕴和现代审判内涵的新型民间青花艺术;而后者则是从传统陶艺延伸、扩展、蜕变为纯粹艺术表达和具有独特审判内涵的一门现代艺术。 相似文献
6.
The nature of the interaction of monomer, and the early stages of growth of oligomers of ethylene on a rather more uniform surface of Cr/SiO2 catalyst than hitherto studied has been investigated by differenceFTIR spectroscopy using C2D4 and C2H4 as reactants both with and without subsequent treatment of the catalyst with CO andTHF. The active catalyst was prepared by reaction of vapour phase CrO2Cl2 with the vicinal hydroxyls of the silica surface. Three distinct kinds of methylene groups were detected. Arguments are given for assigning the peaks at 2935 and 2860 cm–1 to CH2 groups directly bound to the active site and those at 2920 and 2850 to CH2s in the growing chain well removed from the Cr. The peaks at 2160 and 2165 cm–1 are attributed to CD2 groups hydrogen bonded to surface hydroxyls. 相似文献
7.
采用化学共沉淀法作为钴蓝颜料的制备方法,探讨了主要工艺因素对制备钴蓝颜料性能的影响,对制备的样品进行了测试与表征。结果表明:Co2+和Al3+物质的量比为1∶2.5时,制备的钴蓝样品颜色饱和度与明度最高,沉淀剂为尿素时制得的样品的粒度最小,粒度分布比较均匀。前驱体的洗涤过程采取水洗加醇洗的方法可有效减少样品的硬团聚现象,且前驱体的最佳煅烧温度为950℃左右。 相似文献
8.
由于器件的快速退化,101.5小时似乎成了Znse基蓝绿色半导体激光器难于逾越的寿命极限。分析退化机制,发现在强电流注入的半导体激光器中,热退化具有重要影响。研究表明,用作载流子限制层的宽带Ⅱ-Ⅵ族四元合金(如ZnMgSSe)只能对ZnSe中的电子有效地限制,无法对空穴很好地限制;而对BeTe,却只能对空穴进行有效的限制,无法对电子很好地限制。这导致ZnSe(或BeTe)活性层空穴(或电子)漏电发热,引起退化。本文提出以ZnSe/BeTe超晶格为蓝绿发光层,并用包络函数理论具体计算了阱宽、垒宽对载流子能级的不同影响,考察了ZnSe、BeTe厚度比和超晶格周期对带隙、载流子限制能力的调节。为研制新型长寿命蓝绿色半导体激光器提供了一条新的途径。 相似文献
9.
10.
稀土镧、钇对蓝色氧化钨氢还原的影响 总被引:6,自引:2,他引:6
借助于SEM、X射线衍射技术及IPP粉末粒度仪等系统地研究了稀土镧、钇对蓝色氧化钨(BO)氢还原的影响。结果表明:稀土元素镧、钇在蓝色氧化钨的还原钨粉中以氧化物及钨酸盐形式存在;还原后所得的钨粉颗粒大多为规则形状的多面体;稀土镧、钇和铝相似,强烈地抑制BO氢还原钨粉颗粒的长大,而且钇的作用更为显著。 相似文献