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51.
Harshida Parmar Rucha Desai R. V. Upadhyay 《Applied Physics A: Materials Science & Processing》2011,104(1):229-234
Microwave combustion technique modified by post treatment procedure is used to synthesize single-phase spinel ferrites of cobalt, zinc, and substituted magnetic nanoparticles of typical size 390 Å. The post treatment does not alter the crystal structure but increases the crystallinity. This is confirmed by powder x-ray diffraction and Fourier Transform Infrared (FTIR) studies. Citric acid is used as a fuel. The fresh synthesized sample shows an impurity phase in x-ray and in FTIR. This is due to the unreacted citrate molecule adsorbed on the particle surface. It is shown that by treating the sample with 0.1 M HCl, we can eliminate the impurity phase, and one can obtain a pure single phase. The magnetization at 8 kOe increases by nearly 8% after the removal of impurity. In order to remove surface adsorbed OH? ion, samples are treated with NaCl and heated to 200°C for four hours. The XRD result indicates that after the treatment neither the crystallite size nor the distribution changes, but it removes OH? ion. This is also confirmed by FTIR analysis. Thus, this modified technique can be used to synthesize pure nanocrystalline samples of spinel ferrites. 相似文献
52.
Desai Neha S. Barhate Chandrashekhar R. Biyani Sheetal O. Kulkarni Savita R. Nagarsenker Mangal S. 《平面色谱法杂志一现代薄层色谱法》2011,24(4):306-311
JPC – Journal of Planar Chromatography – Modern TLC - Annona squamosa, commonly known as custard apple, possesses various medicinal properties such as antimicrobial, insecticidal,... 相似文献
53.
Mukund G. Kulkarni Sanjay W. Chavhan Mayur P. Desai Yunnus B. Shaikh Dnyaneshwar D. Gaikwad Attrimuni P. Dhondge Ajit S. Borhade Vijay B. Ningdale Deekshaputra R. Birhade Nagorao R. Dhatrak 《Tetrahedron letters》2010,51(34):4494-6381
Application of Wittig olefination-Claisen rearrangement protocol for the short synthesis of furo[2,3-b]indoles is described. 相似文献
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Pramana - A two-dimensional position sensitive neutron detector has been developed. The detector is a3He + Kr filled multiwire proportional counter with charge division position readout and has a... 相似文献
57.
Angela Desai 《Indagationes Mathematicae》2006,17(3):353-359
We prove that any ?d shift of finite type with positive topological entropy has a family of subsystems of finite type whose entropies are dense in the interval from zero to the entropy of the original shift. We show a similar result for ?d sofic shifts, and also show every ?d sofic shift can be covered by a ?d shift of finite type arbitrarily close in entropy. 相似文献
58.
A new, convenient, ecofriendly synthesis of 3,5-diarylisoxazoles is reported from α,β-unsaturated ketoximes. Similarly, a novel synthesis of isoxazole carboxylic acids is also reported. Both the methods use efficient, environmentally friendly, and nontoxic iodoxybenzoic acid (IBX) as an oxidative cyclizing reagent. Easy procedure, environmentally benign reaction conditions, and nontoxicity are advantages to the methodology. 相似文献
59.
The synthesis of a generation 5 (G5) poly(amidoamine) (PAMAM) dendrimer platform having cyclooctyne ligands that were subsequently be used for a copper-free Huisgen 1,3-dipolar cycloaddition (click reaction) with azido modified methotrexate is described. The G5 PAMAM dendrimer was first partially (70%) acetylated and then coupled with 20 cyclooctyne ligands through amide bonds. The remaining primary amine groups on the dendrimer surface were neutralized by acetylation. The platform was then ‘clicked’ with different numbers (5, 10, and 17) of γ-azido functionalized methotrexate. The copper-free click reactions were stoichiometric with excellent yields. 相似文献
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