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581.
Manju Bala Satish Kumar Rekha Devi Avni Khatkar V. B. Taxak Priti Boora S. P. Khatkar 《Journal of fluorescence》2018,28(3):775-784
A series of five new terbium(III) ion complexes with 4,4-difluoro-1-phenylbutane-1,3-dione (HDPBD) and anciliary ligands was synthesized. The composition and properties of complexes were analyzed by elemental analysis, IR, NMR, powder X-ray diffaraction, TG-DTG and photoluminescence spectroscopy. These complexes exhibited ligand sensitized green emission at 546 nm associated with 5D4?→?7F5 transitions of terbium ion in the emission spectra. The photoluminescence study manifested that the organic ligands act as antenna and facilitate the absorbed energy to emitting levels of Tb(III) ion efficiently. The enhanced luminescence intensity and decay time of ternary C2-C5 complexes observed due to synergistic effect of anciliary ligands. The CIE color coordinates of complexes came under the green region of chromaticity diagram. The mechanistic investigation of intramolecular energy transfer in the complexes was discussed in detail. These terbium(III) complexes can be thrivingly used as one of the green component in light emitting material and in display devices. 相似文献
582.
Satish M. Manocha Deval Y. Vashistha L.M. Manocha 《Journal of Sol-Gel Science and Technology》1999,16(3):221-226
Transparent monolithic discs of organic-inorganic hybrid gels have been prepared by hydrolysis-condensation reactions of tetraethyl orthosilicate with 1,4 butanediol. The gels and glasses have been characterized by infrared spectroscopy and 29Si MAS NMR. The characterization of the gels by infrared spectroscopy showed the incorporation of carbonaceous groups in the polymeric structure and Si–C bonding in the glasses. Pyrolysis of the gels has been studied using thermal analysis. It showed that the pyrolysis of the gels occurs in two temperature domains. The first is below 400°C due to condensation reactions and second is in the temperature range 450–550°C due to decomposition of carbonaceous groups and crosslinking. Pyrolysis of the gels at 1000°C resulted in X-ray amorphous, hard black glasses similar to oxycarbide glasses obtained by pyrolysis of siloxanes. On further heat treatment to 1400–1600°C, development of cristobalite structure and crystalline silicon carbide is observed in the otherwise amorphous black mass. The pyrolysed materials have been found to exhibit good resistance towards oxidation at 1000°C. 相似文献
583.
Inside Back Cover: “Head‐to‐Middle” and “Head‐to‐Tail” cis‐Prenyl Transferases: Structure of Isosesquilavandulyl Diphosphate Synthase (Angew. Chem. Int. Ed. 3/2018) 下载免费PDF全文
Jian Gao Dr. Tzu‐Ping Ko Lu Chen Dr. Satish R. Malwal Jianan Zhang Xiangying Hu Fiona Qu Dr. Weidong Liu Dr. Jian‐Wen Huang Dr. Ya‐Shan Cheng Dr. Chun‐Chi Chen Yunyun Yang Prof. Dr. Yonghui Zhang Prof. Dr. Eric Oldfield Prof. Dr. Rey‐Ting Guo 《Angewandte Chemie (International ed. in English)》2018,57(3):851-851
584.
Yves Rubin Timothy C. Parker Salvador J. Pastor Satish Jalisatgi Christophe Boulle Charles L. Wilkins 《Angewandte Chemie (International ed. in English)》1998,37(9):1226-1229
A logical precursor of macrocycle C 60 H 6 , cyclophane C60H6(CO)12 ( 1 ) represents a building block in a possible total synthesis of C60. In Fourier transform ion cyclotron resonance laser desorption mass spectroscopic experiments in the negative-ion mode, 1 fragments to C60H6 ( 2 ) under successive loss of CO. Further loss of six H atoms and rearrangement gives C60 ions with a fullerenic structure. 相似文献