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991.
Tandrima Chaudhuri Soumyaditya Mula Subrata Chattopadhyay Manas Banerjee 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):739-744
The absorption and emission spectroscopic investigations of the C-8-phenyl substituted analogue of the pyrromethene dye PM567 in various polar, non-polar as well as protic and aprotic solvents are reported. The solvatochromic shifts of the spectral bands were studied in a multitude of polar, non-polar and protic, aprotic solvents followed by a multilinear regression in which several solvent parameters were simultaneously analysed. Comparison of the experimental results with those obtained by gas phase ab initio computation with CIS, TD-HF and TD-DFT theories using 6-31G* basis set reveal an overestimation of the experimentally measured excitation parameters by all these theoretical models. However, the trends in the experimental results agree with those calculated theoretically. 相似文献
992.
We prove some uniqueness theorems concerning the derivatives of meromorphic functions when they share two or three sets which will improve some existing results. 相似文献
993.
Crystallography Reports - A co-crystal of 2-aminobenzothiazol and 1-methylisatin (III) was synthesized and characterized by elemental analysis, Fourier-transform infrared spectroscopy, nuclear... 相似文献
994.
S. Banerjee 《Phase Transitions》2013,86(1-4):389-406
Abstract The continuous ordering process can be viewed as a development and a gradual amplification of concentration modulations with wave lengths of the order of a few lattice spacings. How the development of different concentration modulaltions leads to different superlattice structures in cubic systems is explained with the help of some illustrative examples. The importance of concentration modulations with special point wave vectors in the stability of the various coherent superlattice structures is discussed. Experimental evidences for such continuous ordering is cited from recent results on ordering in Ni-Mo alloys. The evolution of ordering in some systems can also be viewed as progressively tiling the disordered lattice by superlattice tiles. When more than one type of coherent superlattice tiles compete, juxtaposition of different types of tiles can occur during the course of ordering. The transitional states between the short range and the long range ordered Ni-Mo alloys indeed exhibit such structures where different types of superlattice tiles decorate the fcc lattice. The role of special point concentration waves in the development of such structures will be discussed in relation to the secondary ordering processes involving two perpendicular ?1 ½ 0? waves and a combination of an ?1 ½ 0? and an appropriate ?100? wave. 相似文献
995.
996.
An asymmetric synthesis of the calcimimetic agent NPS R‐568 using a (1R,2S)‐N‐benzylephedrine‐promoted addition of dimethylzinc to a diphenylphosphinoylimine derived from 3‐methoxybenzaldehyde is described. The enantiomeric ratio of the key amine fragment was determined to be 93:7 (86% ee), favoring the (R)‐enantiomer by derivatization and chiral stationary phase HPLC analysis. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
997.
Jana Shibu Narayan Sing Dilip Banerjee Subhadip Haldar Pallab Kanti Dasgupta Barun Kar Amit Sharma Nanaocha Bandyopadhayay Rajib Mukherjee Pulok K. 《平面色谱法杂志一现代薄层色谱法》2021,34(6):521-530
JPC – Journal of Planar Chromatography – Modern TLC - Piperine is the most important alkaloid molecule present in Piper nigrum. In this study, a simple, rapid, quantitative... 相似文献
998.
999.
The cyclic diones (1), (5), (8) and (11) on treatment with iodine and methanol underwent fragmentation yielding the anisole derivatives (4), (6), (9) and (12) respectively. 相似文献
1000.
The reactions of bis(cyclopentadienyl)titanium(IV) chloride with a new class of bis(thiosemicarbazones) (H2L), derived by condensing isatin with different N(4)‐substituted thiosemicarbazides, have been studied both by a conventional stirring method and also using microwave technology. Binuclear products of type [{(η5‐C5H5)2TiCl} 2(L)] have been isolated in both cases. Tentative structural conclusions are drawn for the reaction products based upon analysis, electrical conductance, magnetic moment and spectral (UV‐visible, IR, 1H NMR and 13C NMR) data. FAB mass spectra of these compounds were also recorded to confirm the binuclear structures. Studies were conducted to assess the growth inhibiting potential of the ligands and complexes against various fungal, viral and bacterial strains. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献