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IR, Raman and surface‐enhanced Raman scattering (SERS) spectra of 5‐sulphosalicylic acid were recorded and analysed. The vibrational wavenumbers were computed by density functional theoretical (DFT) method using B3LYP/6–31G* basis. The bands due to the stretching modes CO, C S and SO2 are intense in the SERS spectrum. The C H stretching mode also appears in the SERS spectrum. The molecule is found to adsorb through both the carboxyl and sulphonyl groups. A possible tilted orientation of the molecule is suggested. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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Bisht  Babita  Bhardwaj  Priyank  Giri  Manoj  Pant  Sanjay 《Journal of fluorescence》2021,31(6):1787-1795
Journal of Fluorescence - The methyl orange [C14H14N3SO3Na], an azo dye exhibited strong emission and large Stokes shift in various solvents, and the largest shift (Δλ = 125.51nm or...  相似文献   
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Lanthanum fluoride nanorod and nanoparticles have been synthesized by a simple method with and without sonication, respectively. Thermogravimetric/differential thermal analysis confirms the sample formation at low temperature for the sonication-assisted sample than the directly prepared sample. The structure of the prepared lanthanum fluoride nanorods and nanoparticles has been analyzed by X-ray diffraction studies and the micro-structural properties have been studied using transmission electron microscopy. The transmission electron microscopic image reveals a capsule-like shape for the sample prepared under sonication. Ion conduction and conductivity analysis of the prepared nanorods and nanoparticles has been studied using AC impedance spectroscopy, and the ionic conductivity was found to increase by an order for the sample prepared with sonication.  相似文献   
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The synthesis of novel spatially directional multivalent resorcin[4]arene cavitand glycoconjugates (RCGs) and their ability to catalyze organic reactions is reported. The β‐d ‐glucopyranoside moieties on the upper rim of the “bowl”‐shaped resorcin[4]arene cavitand core are capable of multiple hydrogen‐bond interactions resulting in a pseudo‐cavity, which has been investigated for organic transformations in aqueous media. The RCGs have been demonstrated to catalyze thiazole formation, thiocyanation, copper(I)‐catalyzed azide alkyne cycloaddition (CuAAC), and Mannich reactions; they impart stereoselectivity in the three‐component Mannich reaction. Thermodynamic values obtained from 1H diffusion‐ordered spectroscopy (DOSY) experiments suggest that the upper saccharide cavity of the RCG and not the resorcin[4]arene cavity is the site of the complexation event.  相似文献   
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Generators of \(\operatorname{SO}(8)\) group have been described by using direct product of the Gamma matrices and the Pauli Sigma matrices. We have obtained these generators in terms of generalized split octonion also. These generators have been used to describe the rotational transformation of vectors in \(\operatorname{SO}(7)\) symmetry group.  相似文献   
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An access to different glycohybrids involving nucleophilic addition of N- and C-nucleophiles to the butenonyl glycosides followed by cyclization and subsequent reactions is reported. In the present communication, three different prototypes, β-D-glucopyranosylmethyl pyrazolines, β-D-glucopyranosylmethyl pyrimidines and β-D-glucopyranosylmethyl biphenyls, were prepared in moderate to good yields.  相似文献   
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Postulating the existence of magnetic monopole in electromagnetism and Heavisidian monopoles in gravitational interactions, a unified theory of gravi-electromagnetism has been developed on generalizing the Schwinger-Zwanziger formulation of dyon to quaternion in simple and consistent manner. Starting with the four Lorentz like forces on different charges, we have generalized the Schwinger-Zwanziger quantization parameters in order to obtain the angular momentum for unified fields of dyons and gravito-dyons (i.e. Gravi-electromagnetism). Taking the unified charge as quaternion, we have reformulated manifestly covariant and consistent theory for the dynamics of four charges namely electric, magnetic, gravitational and Heavisidian associated with gravi electromagnetism.  相似文献   
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