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161.
Rajan Kumar Subir Kumar Ray Dr. Saikat Mukherjee Sudipta Saha Dr. Arijit Bag Prof. Dr. Pradip Kr. Ghorai Prof. Dr. Nirmalya Ghosh Prof. Dr. Raja Shunmugam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(59):13514-13522
The development of organic photoluminescent materials, which show promising roles as catalysts, sensors, organic light-emitting diodes, logic gates, etc., is a major demand and challenge for the global scientific community. In this context, a photoclick polymerization method is adopted for the growth of a unique photoluminescent three-dimensional (3D) polymer film, E, as a model system that shows emission tunability over the range 350–650 nm against the excitation range 295–425 nm. The DFT analysis of energy calculations and π-stacking supports the spectroscopic observations for the material exhibiting a broad range of emission owing to newly formed chromophoric units within the film. Full polarization spectroscopic Mueller matrix studies were employed to extract and quantify the molecular orientational order of both the ground (excitation) and excited (emission) state anisotropies through a set of newly defined parameters, namely the fluorescence diattenuation and fluorescence polarizance. The information contained in the recorded fluorescence Mueller matrix of the organic polymer material provided a useful way to control the spectral intensity of emission by using pre- and post-selection of polarization states. The observation was based on the assumption that the longer lifetime of the excited dipolar orientation is attributed to the compactness of the film. 相似文献
162.
Preparation,characterizations and biological evaluations of new copper(II) complexes containing ONO pincer type ligands
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A new heterocyclic Schiff bases, 6‐methyl/8methyl‐2‐oxo‐1,2‐dihydroquinoline‐3‐carboxaldehyde semicarbazones (H2‐6MOQsc‐H) ( H 2 L 1 ) and (H2‐8MOQsc‐H) ( H 2 L 2 ) and their corresponding copper(II) complexes [CuCl2(H2‐6MOQsc‐H)].3H2O ( 1 ), [CuCl2(H2‐8MOQsc‐H)].3H2O ( 2 ), [CuNO3(H2‐6MOQsc‐H)(H2O)].NO3 ( 3 ) and [CuNO3(H2‐8MOQsc‐H)(H2O)].NO3 ( 4 ) have been synthesized and characterized by various physicochemical techniques. The single crystal X‐ray diffraction and spectral data revealed that all of the complexes ( 1‐4 ), the ligands coordinated to the Cu(II) ion in a neutral manner via ONO donor atoms and all the complexes exhibited distorted squarepyramidal geometry. The consequence of electronegativity and ring size of nitrogen heterocyclic moiety of ONO donor type of copper(II) chelates on nucleic acid interaction and albumin binding was investigated by in vitro experiments. The interaction of compounds with calf‐thymus DNA (CT‐DNA) has been explored by absorption and emission titration, which exposed those ligands/complexes, could bind with CT‐DNA through electrostatic interaction. The results of gel electrophoresis proved the ability of complexes ( 1‐4 ) to cleave the pBR322 plasmid DNA. The interaction of serum albumin (BSA) was investigated by UV‐Vis, fluorescence, synchronous and three dimensional fluorescence spectra. In addition, radical scavenging activity, antifungal activity and cytotoxicity of the newly synthesized compounds were also evaluated. From the results of in vitro studies, it is seen that complex 3 has more potential as compared with other complexes and ligands. 相似文献
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The development of cube texture after heavy cold rolling (~95%) and annealing has been studied in pure Ni, Ni–5 at% W and Ni–5 at% Mo alloys. The two Ni alloys develop a much sharper cube texture compared to pure Ni, thus indicating the beneficial effect of W or Mo addition. W and Mo enhance the cube texture intensity in Ni by decreasing the volume fraction of the rotated cube grains. The impact of W and Mo addition is seen from a very early stage of recrystallization, where rotated cube grains form in pure Ni as opposed to sharp cube-oriented grains in the two Ni alloys. The results negate the widely perceived theory of ‘detrimental effect of impurities’ on the development of cube texture. 相似文献
165.
Ester Abtew Abraham J. Domb Arijit Basu 《Journal of polymer science. Part A, Polymer chemistry》2017,55(16):2657-2662
We report on the synthesis of polypeptides with saccharide side chains starting from d ‐glucosaminic acid. The hydroxyl groups were first protected by benzylation, followed by N‐carboxyanhydride formation, which was polymerized by ring opening to form a high molecular weight polyamide. De‐protection of the benzyl groups yields a polypeptide with fully de‐protected saccharide side chains. The resulting new non‐ionic, water soluble, and optically active polymers possessing the properties of both peptides and saccharides have potential use as scaffolds for tissue engineering and drug carriers. The method described here may be extended to any saccharide α‐amino acid. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2657–2662 相似文献
166.
Research on Chemical Intermediates - The discharge of hexavalent chromium [Cr(VI)] has resulted in significant pollution because of the presence of Cr(VI) oxyanions. They are highly water-soluble,... 相似文献
167.
A Facile and Convenient Method for the Synthesis of 8-Methoxy 10,11-Dihydronaphtho [1,2-b]Quinolines
Dihydronaphthoquinolines are relatively rare polycyclic heterocyclic compounds. We wish to report a simple and convenient preparative method for hitherto unknown compounds with these new structural features. 6-methoxy tetralone1 (I) 3.5g (.02 mole) in 3 ml DMF was added slowly to 4.6g (.02 mole) of POCl3 in 3ml DMF at 0°C. The mixture was stirred for 5 hrs. and the temp. was then gradually raised from 0° to 60–65°C. The resultant complex was treated with aq. sodium acetate solution till pH5–6 was reached. The extract on usual purification, furnished 3.2g (80°%.) of 1-chloro, 6-methoxy, 1,2,3,4 tetrahydro naphthalene-2-aldehyde(II)+2 相似文献
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This paper provides a new framework for the derivation and estimation of consumption and equity premium functions. Applying duality in a dynamic context, we show that equity premium and consumption functions can be easily obtained from the indirect utility function. Our new framework, therefore, does not require explicit specification of underlying consumer preferences. Using aggregate US data (1929–2000) we estimate the consumption and equity premium functions using a nonparametric technique. We find that the model does well in explaining the observed smooth consumption patterns and does reasonably well in explaining the high mean and volatility of equity premia. 相似文献