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61.
N1-Hydroxy-2,4,5-trisubstituted imidazoles were synthesized starting from 1,2-diketones. The crystal structure of 4,5-dimethyl-2-(3-nitrophenyl)-1H-imidazol-1-ol has been determined. An unusual intermolecular hydrogen bonding through the association of water molecule has been reported. These imidazole derivatives can be thought of as the organic precursor for the synthesis of zinc oxide nano particles. 相似文献
62.
63.
Dr. Staffan Bergwall Dr. Arun S. Nigavekar 《Zeitschrift für Physik B Condensed Matter》1969,10(2):107-115
The results of a systematic investigation of the intensity distribution near the short wavelength limit of the continuous X-ray spectrum for the most common rare earth oxides are reported. Anomalies in the band structure of some oxides have been observed and are discussed in terms of localized energy levels in the forbidden band due to the existence of colour centres. This implies that the physical properties of pure compounds strongly depend on the precise experimental conditions of preparation. 相似文献
64.
Couturier M Ménard F Ragan JA Riou M Dauphin E Andresen BM Ghosh A Dupont-Gaudet K Girardin M 《Organic letters》2004,6(11):1857-1860
Lewis-base-catalyzed cycloisomerization of bis(enones) to decalins has been demonstrated as an alternative to the traditional Lewis acid catalyzed Diels-Alder cycloaddition. In this process, a trialkylphosphine mediates both bond formation steps in two distinct catalytic cycles. The single-pot operation generates two carbon-carbon bonds and up to five contiguous stereocenters in one step, starting from achiral, aliphatic substrates; eight examples are provided. [reaction: see text] 相似文献
65.
Arun Kumar Gupta 《Tetrahedron letters》2004,45(21):4113-4116
1-(2-Iodophenyl)-1H-tetrazole 2 was synthesized by the reaction of 2-iodoaniline, sodium azide and triethyl orthoformate in acetic acid. The newly synthesized ligand 2 was successfully used in Heck reaction to give the cross-coupled products in excellent yields. 相似文献
66.
We demonstrate resonant tunneling of ultracold atoms through potentials produced by the interaction of atoms with the vacuum field of a system of cavities. We show the close connection of the transmission characteristics to the resonant states in vacuum induced potentials. Transmission of cold atoms, though sharing some features with tunneling in finite semiconductor superlattices, is strongly dependent on the coherent addition of amplitudes from various wells and barriers. 相似文献
67.
We report the integration of inorganic nanotubes into metal-oxide-solution field effect transistors (FETs) which exhibit rapid field effect modulation of ionic conductance. Surface functionalization, analogous to doping in semiconductors, can switch the nanofluidic transistors from p-type to ambipolar and n-type field effect transistors. Transient study reveals the kinetics of field effect modulation is controlled by ion-exchange step. Nanofluidic FETs have potential implications in subfemtoliter analytical technology and large-scale nanofluidic integration. 相似文献
68.
Size controlled cubic Fe3O4 nanoparticles in the size range 90–10 nm were synthesized by varying the ferric ion concentration using the oxidation method. A bimodal size distribution was found without ferric ion concentration and the monodispersity increased with higher concentration. The saturation magnetization decreased from 90 to 62 emu/g when the particle size is reduced to 10 nm. The Fe3O4 nanoparticles with average particle sizes 10 and 90 nm were surface modified with prussian blue. The attachment of prussian blue with Fe3O4 was found to depend on the concentration of HCl and the particle size. The saturation magnetization of prussian blue modified Fe3O4 varied from 10 to 80 emu/g depending on the particle size. The increased tendency for the attachment of prussian blue with smaller particle size was explained based on the surface charge. The prussian blue modified magnetite nanoparticles could be used as a radiotoxin remover in detoxification applications. 相似文献
69.
70.
Bosco Christin Maria Arputham Ashwin Ramesh Kumar Chitumalla Arulanandu Herculin Arun Baby Joonkyung Jang Paulpandian Muthu Mareeswaran 《Journal of inclusion phenomena and macrocyclic chemistry》2018,90(1-2):51-60
The supramolecular host–guest investigation of Coumarin 460 (C460), a salient coumarin family dye molecule is studied with a noteworthy host molecule, p-sulfonatocalix[4]arene (p-SC4). The investigation is carried out by both experimental and theoretical approach. The binding affinity of C460 with p-SC4 is experimentally studied using absorption, emission, excited state lifetime and Cyclic Voltammetry methods. The binding constant is around 103 M??1, which shows potent binding. The binding stoichiometry is 1:1. The binding orientations and binding energies are studied using computational simulations. The mode of binding is also established using NMR spectral techniques. 相似文献