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1.
S. Venkatesan S. Suresh P. Ramu M. Kandasamy J. Arumugam S. Thambidurai K.M. Prabu N. Pugazhenthiran 《印度化学会志》2022,99(5):100436
A facile biosynthesis route was followed to prepare zinc oxide nanoparticles (ZnO NPs) using Euphorbia milii (E. milii) leaf constituents. The SEM images exhibited presence of spherical ZnO NPs and the corresponding TEM images disclosed monodisperse nature of the ZnO NPs with diameter ranges between 12 and 20 nm. The Brunauer–Emmett–Teller (BET) analysis revealed that the ZnO NPs have specific surface area of 20.46 m2/g with pore diameter of 2 nm–10 nm and pore volume of 0.908 cm3/g. The EDAX spectrum exemplified the existence of Zn and O elements and non-appearance of impurities that confirmed pristine nature of the ZnO NPs. The XRD pattern indicated crystalline peaks corresponding to hexagonal wurtzite structured ZnO with an average crystallite size of 16.11 nm. The FTIR spectrum displayed strong absorption bands at 512 and 534 cm?1 related to ZnO. The photocatalytic action of ZnO NPs exhibited noteworthy degradation of methylene blue dye under natural sunlight illumination. The maximum degradation efficiency achieved was 98.17% at an illumination period of 50 min. The reusability study proved considerable photostability of the ZnO NPs during photocatalytic experiments. These findings suggest that the E. milii leaf constituents can be utilized as suitable biological source to synthesis ZnO NPs for photocatalytic applications. 相似文献
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The cyclophanes derived from 2,6-bis(chloromethyl)benzoquinone and suitable dithiols were reduced with sodium dithionate and then further coupled with various dibromides to give intra annularly linked bicyclic cyclophanes, which forms charge transfer complexes with TCNQ and TCNE. 相似文献
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Simon G. Bott Alan P. Marchand Dongxia Xing Rajesh Shukla Stephen James Obrey K. Venkatesan J. Narasimha Moorthy 《Journal of chemical crystallography》1997,27(11):661-665
NaBH4 reduction of a cage dione proceeds in a stereospecific fashion to give theendo,endo-diol. This reactivity is related to the crystal structure. 相似文献
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Fluorenophanes derived from 2,7-bis-(bromomethyl)-9,9′-diheptyl-9H-fluorene and various diols exhibit excellent photoluminescence properties. 相似文献
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Wave propagation in a piezoelectric human bone of arbitrary cross section with a circular cylindrical cavity 总被引:1,自引:0,他引:1
A theoretical study of wave propagation in a piezoelectric cylinder of infinite length of arbitrary cross section with a circular cylindrical cavity of class 6 is investigated. The frequency equations are obtained by using the Fourier expansion collocation method and are analyzed numerically. The frequencies are evaluated for circular, elliptic, and cardioidal sections of bone and are tabulated. A plot of frequency spectrum is also presented for the cardioidal cross-section bar. 相似文献
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Sharmin Kharrazi S.W. Gosavi T. Venkatesan J. Urban S.-W. Cheong 《Solid State Communications》2006,138(8):395-398
We report on the synthesis of TbMnO3 nanoparticles by chemical co-precipitation route and their structural, chemical bonding, magnetic and dielectric properties. It is shown that the interesting multiferroic properties of this system as reflected by the concurrent occurrence of magnetic and dielectric transitions are retained in the nanoparticles (size∼40 nm). However, the nanoparticle constitution and properties are seen to depend significantly on the calcination temperature. While the nanoparticles obtained by calcination at 800 °C correspond very well with the reported properties of single phase TbMnO3 (all the key magnetic and dielectric features near 7, 27 and 41 K, albeit with reduced dielectric constant) the nanoparticles obtained by calcination at 900 °C develop a Tb deficient skin which softens the transitions, reducing the dielectric constant further. 相似文献
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