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101.
102.
Elegbede AI Haldar MK Manokaran S Kooren J Roy BC Mallik S Srivastava DK 《Chemical communications (Cambridge, England)》2007,(32):3377-3379
We offer a novel strategy for designing "multi-prong" inhibitors of enzymes by incorporating selective ligands on the liposomal surface. 相似文献
103.
Bhattacharya S Chattopadhyay S Nayak SK Bhattacharya Banerjee S Banerjee M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,68(3):427-431
The host-guest interactions of various tetraarylporphyrins (TP), viz., 5,10,15,20-tetraphenyl-21H,23H-porphyrin (1), 5,10,15,20-tetrakis(octadecyloxyphenyl)-21H,23H-porphyrin (2) and 5,10,15,20-tetrakis(dodecyloxyphenyl)-21H,23H-porphyrin (3) with C60 and C70 have been studied by 1H NMR, UV-vis and fluorescence spectroscopic techniques in toluene medium. All the fullerene/porphyrin complexes are found to be stable with 1:1 stoichiometry. Binding constants (K) of all the fullerene/porphyrin complexes have been determined by fluorescence quenching experiment. The trend in K values revealed that the presence of long chain n-alkyl group in tetraarylporphyrin effectively and remarkably increases the selectivity ratio of C70 over C60. Theoretical calculations have extended a good support in interpreting the stability difference between various fullerene/TP complexes. 相似文献
104.
Lewis acid-mediated unprecedented ring-opening rearrangement of 2-aryl-N-tosylazetidines to enantiopure (E)-allylamines 总被引:1,自引:0,他引:1
A highly efficient strategy for Cu(OTf)2-mediated ring-opening of 2-aryl-N-tosylazetidines in polar and coordinating solvents followed by an unprecedented rearrangement to substituted achiral and chiral (E)-allylamines (ee >99%) is reported. The methodology has been applied for the synthesis of gamma-unsaturated-beta-amino acids. A plausible mechanism for the rearrangement is also described. 相似文献
105.
A click-reagent version of the Sonogashira-coupling protocol has been developed. Diarylalkynes with donor and/or acceptor substituents have been synthesized via this protocol at moderate to excellent yields and with no or drastically reduced quantities of undesired homocoupled side products. This protocol is green-solvent compatible, air-insensitive, and effective under microwave conditions. 相似文献
106.
Bhunia MK Das SK Pachfule P Banerjee R Bhaumik A 《Dalton transactions (Cambridge, England : 2003)》2012,41(4):1304-1311
In an effort to expand the realm of possibilities of nitrogen-rich porous materials that could be used in catalysis, herein we report the synthesis of a new highly nitrogen rich (ca. 45%) porous covalent imine network (CIN-1) material employing simple Schiff base chemistry and further grafting its surface with palladium. Pd-loaded CIN-1 support acts as a truly heterogeneous catalyst towards Suzuki C-C coupling reaction between aryl halides with arylboronic acids. High surface area and excellent accessibility of the catalytic sites make it very efficient for heterogeneous catalysis. The stability of the catalyst due to intimate contact between nitrogen-rich organic support and metal allows several reuses with only a minor loss in catalytic activity. 相似文献
107.
Zhida Xu Manas R. Gartia Charles J. Choi Jing Jiang Yi Chen Brian T. Cunningham Gang Logan Liu 《Journal of Raman spectroscopy : JRS》2011,42(11):1939-1944
Anomalous surface‐enhanced Raman scattering (SERS) peaks were identified for liquid sample stored in polypropylene (PP) centrifuge tubes for months. We observed unexpected Raman peaks during experiments with thiamine hydrochloride aqueous solutions stored in PP tubes for 2 months. In order to identify the contaminants, we have performed SERS experiments on deionized (DI) water stored in PP centrifuge tubes for 2 months and compared them with those from fresh DI water sample. We have also carried out ultraviolet (UV) absorption spectra for both fresh and contaminated water. We believe that the water is contaminated because of chemicals leaching from the PP tube. From the gas chromatography‐mass spectrometry data, the main contaminants were found to be phthalic acid (PA) and its derivatives. Further SERS and UV absorption experiment for PA correlated well with the anomalous peaks identified earlier. We qualitatively confirmed the identification and quantitatively estimated the concentration of the suspect contaminants as between 1 and 10 µM with both SERS and UV absorption spectroscopy. With UV absorption spectroscopy, we precisely estimated the concentration as 2.1 µM . We have shown that the sample in PP tube can be contaminated by the leaching chemicals upon long‐term storage, and suggest SERS and UV absorption spectroscopy as two quick and simple techniques to detect the contamination. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
108.
Bhattacharya S Banerjee M Mukherjee AK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(12):2563-2569
[60]fullerene has been shown to form 1:1 molecular complexes with pyridine and some methylated pyridines such as 2-picoline, 3-picoline, 4-picoline, 2,6-lutidine and 2,4,6-collidine in CCl4 medium by absorption spectrometric method. Well defined charge transfer (CT) bands have been observed for complexes of C60 with all the pyridines studied except 4-picoline. From an analysis of the trends in the CT absorption bands the ionisation potentials of the methylpyridines have been determined. The electron affinity of C60 has also been determined from the spectral data. The formation constants of the complexes exhibit a very good linear free energy relationship from which the Hammett p parameter for the complexation process is found to be -2.96. 相似文献
109.
Madhuri Mukhopadhyay Ram Kuntal Hazra Manas Ghosh Samaresh Mukherjee Shankar P. Bhattacharyya 《Central European Journal of Physics》2012,10(4):983-988
We present a quantized model of a harmonically confined dot atom with inherent damping in the presence of a transverse magnetic
field. The model leads to a non-Hermitian Hamiltonian in coordinate space. We have analytically studied the effects of damping
on Rabi type oscillations of the system. The model explains the decoherence of Rabi oscillations in a Josephson Junction. 相似文献
110.
Biswajit Mallick Ramesh Chandra Behera Simanchal Panigrahi Tanmaya Badapanda Biswanath Parija Banita Behera Manas Panigrahi Madhumita Sarangi 《Indian Journal of Physics》2009,83(4):525-529
Electron microscopy is an important characterization technique for the study of textile fibre as it gives more information
on fabric wear, nature of fibre fracture, chemical degradation, abrasion, fatigue and many others. Electron Probe Micro Analyzer
(EPMA) micrographs of virgin and some neutron-irradiated samples (graphite coated) are discussed. The filament diameter, D, of virgin PET fibre obtained from EPMA study was 12.5 μn. The surface topography of single filament distinctly reveals the
core and sheath parts of the filament. The core diameter of the virgin fibre was estimated to be 1.43 μm. The fibre irradiated
at fluence 1 × 1012 n/cm2 shows radiation induced sphere like polymer balls or spherulites of diameter 2.27 μm in the expanded core region. Due to
irradiation, the sheath area crosslinks with expanded core region, which may be responsible for increase of strength and hardness
of the polymer materials. Moreover, the micrograph at 3000 X magnifications clearly shows that there is no preferred orientation
of the polymer in any direction confirming the isotropic nature of the sample.
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