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71.
Malabika Pramanik 《Transactions of the American Mathematical Society》2002,354(4):1651-1665
A two-dimensional weighted integral in is proposed as a tool for analyzing higher-dimensional unweighted integrals, and a necessary and sufficient condition for the finiteness of the weighted integral is obtained.
72.
A Leistenschneider T Aumann K Boretzky D Cortina J Cub U Datta Pramanik W Dostal T W Elze H Emling H Geissel A Grünschloss M Hellstr R Holzmann S Ilievski N Iwasa M Kaspar A Kleinb?hl J V Kratz R Kulessa Y Leifels E Lubkiewicz G Münzenberg P Reiter M Rejmund C Scheidenberger C Schlegel H Simon J Stroth K Sümmerer E Wajda W Walús S Wan 《Physical review letters》2001,86(24):5442-5445
The dipole response of stable and unstable neutron-rich oxygen nuclei of masses A = 17 to A = 22 has been investigated experimentally utilizing electromagnetic excitation in heavy-ion collisions at beam energies about 600 MeV/nucleon. A kinematically complete measurement of the neutron decay channel in inelastic scattering of the secondary beam projectiles from a Pb target was performed. Differential electromagnetic excitation cross sections d sigma/dE were derived up to 30 MeV excitation energy. In contrast to stable nuclei, the deduced dipole strength distribution appears to be strongly fragmented and systematically exhibits a considerable fraction of low-lying strength. 相似文献
73.
Harjyoti Thakuria Ballav Moni Borah Avijit Pramanik Gopal Das 《Journal of chemical crystallography》2007,37(12):807-816
Abstract This paper describes the solid-state synthesis and systematic studies of versatile supramolecular self-assembly of 14 new
series of organic salt cocrystals. Hierarchical self-assembly in the solid state utilizes the cooperative interaction of hydrogen
bonding, electrostatic and π–π interactions. These salts are crystallized as a highly ordered self-assembly directed by intermolecular
non-covalent interaction.
Index Abstract Fourteen cocrystals of organic salt have been characterized by single crystal X-ray diffraction and their solid-state packing
pattern has been compared.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
74.
75.
Susnata Pramanik Soumen De Prof. Dr. Michael Schmittel 《Angewandte Chemie (International ed. in English)》2014,53(18):4709-4713
The interplay of biological machines depends critically on the bidirectionality of chemical information exchange. The implementation of such a communication procedure for abiological systems is achieved using two nanoswitches that both operate as transmitters and receivers by transfering copper ions in oxidation states +I and +II. Even at micromolar concentrations, communication in both directions is remarkably fast, occurring at t1/2=2–3 min. Metal ion translocation triggers a 20 Å relocation of the toggle at both nanoswitches, entailing major geometric and electronic changes. 相似文献
76.
A one-pot three-component protocol has been developed for the synthesis of amino ester-embedded benzimidazoles under metal-free neutral conditions. Sequentially, the methodology involves coupling of an amino ester with 1-fluoro-2-nitrobenzene, reduction of the coupled nitroarene by sodium dithionite, and cyclization of the corresponding diamine with an aldehyde. 相似文献
77.
Harun A. R. Pramanik Dr. Gobinda Das Prof. Chira R. Bhattacharjee Dr. Pradip C. Paul Dr. Paritosh Mondal Dr. S. Krishna Prasad Dr. D. S. Shankar Rao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(39):13151-13159
A novel photoluminescent room‐temperature liquid‐crystalline salicylaldimine Schiff base with a short alkoxy substituent and a series of lanthanide(III) complexes of the type [Ln(LH)3(NO3)3] (Ln=La, Pr, Sm, Gd, Tb, Dy; LH=(E)‐5‐(hexyloxy)‐2‐ [{2‐(2‐hydroxyethylamino)ethylimino]methyl}phenol) have been synthesized and characterized by FTIR, 1H and 13C NMR, UV/Vis, and FAB‐MS analyses. The ligand coordinates to the metal ions in its zwitterionic form. The thermal behavior of the compounds was investigated by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). The ligand exhibits an enantiotropic hexagonal columnar (Colh) mesophase at room temperature and the complexes show an enantiotropic lamellar columnar (ColL) phase at around 120 °C with high thermal stability. Based on XRD results, different space‐filling models have been proposed for the ligand and complexes to account for the columnar mesomorphism. The ligand exhibits intense blue emission both in solution and in the condensed state. The most intense emissions were observed for the samarium and terbium complexes, with the samarium complex glowing with a bright‐orange light (ca. 560–644 nm) and the terbium complex emitting green light (ca. 490–622 nm) upon UV irradiation. DFT calculations performed by using the DMol3 program at the BLYP/DNP level of theory revealed a nine‐coordinate structure for the lanthanide complexes. 相似文献
78.
Nilay K. Pramanik Ramsankar Haldar Utpal K. Niyogi MD. Sarwar Alam 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):296-307
The non-isothermal crystallization kinetics was studied by differential scanning calorimetric analysis on nylon 66 and e-beam irradiated nylon 66 at different cooling rates. The Modified Avrami equation, the Ozawa equation and the Combined Avrami-Ozawa equation were applied to study the kinetics of non-isothermal crystallization of nylon 66. The crystallization behavior of pristine nylon 66 polymer was compared with that of e-beam irradiated nylon 66 and observed that the kinetics of non-isothermal crystallization of nylon66 was affected largely upon e-beam irradiation. E-beam irradiation not only decreased the crystallization temperature of nylon 66, but influenced the mechanism of nucleation and crystal growth and reduced the overall crystallization rate of nylon 66 also. The crystallization activation energy calculated by the Kissinger method for irradiated nylon 66 was lower than that of pristine nylon 66. 相似文献
79.
A highly efficient protocol for the library synthesis of biologically important 3H,3′H-spiro[benzofuran-2,1′isobenzofuran]-3,3′-diones has been developed by employing silica sulfuric acid (SSA) as solid acid support under solvent-free condition. The dual characteristics of SSA, as an activating agent as well as oxidizing agent, have been well exposed in these syntheses. The intrinsic advantages of the methodology are the use of solvent-free reaction condition without using any toxic reagents or metal catalyst, operational simplicity, recyclability of the solid support, good availability of the starting materials, and excellent yields which make the method attractive, economic, and ‘benign by design’. 相似文献
80.
A cost-effective and eco-friendly synthesis of 2-aryl-1-arylmethyl-1H-benzimidazoles has been developed through the condensation of different aldehydes with o-phenylenediamine using alumina-sulfuric acid as a recyclable heterogeneous solid acid catalyst. Morphological properties of the catalyst have been investigated. Effect of different solvents and comparison of alumina-sulfuric acid with different acid catalysts have also been studied. A plausible mechanistic pathway has been proposed on the basis of the isotope labelling experiments where catalytic behaviour of alumina-sulfuric acid has been explained. 相似文献