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131.
Chandrasekhar S Rao CL Reddy MS Sharma GD Kiran MU Naresh P Chaitanya GK Bhanuprakash K Jagadeesh B 《The Journal of organic chemistry》2008,73(23):9443-9446
Short homo-oligomers of a new building block, cis-beta(2,3)-furanoid sugar aminoxy acid, are designed, characterized, and found to exhibit rigid ribbon-like secondary structures composed of 5/7 bifurcated intramolecular hydrogen bonds. 相似文献
132.
Chandrasekhar V Pandian BM Boomishankar R Steiner A Vittal JJ Houri A Clérac R 《Inorganic chemistry》2008,47(11):4918-4929
The reaction of LH3 with Ni(ClO4)(2).6H 2O and lanthanide salts in a 2:2:1 ratio in the presence of triethylamine leads to the formation of the trinuclear complexes [L2Ni2Ln][ClO4] (Ln=La (2), Ce (3), Pr (4), Nd (5), Sm (6), Eu (7), Gd (8), Tb (9), Dy (10), Ho (11) and Er (12) and L: (S)P[N(Me)NCH-C6H3-2-O-3-OMe]3). The cationic portion of these complexes consists of three metal ions that are arranged in a linear manner. The two terminal nickel(II) ions are coordinated by imino and phenolate oxygen atoms (3N, 3O), whereas the central lanthanide ion is bound to the phenolate and methoxy oxygen atoms (12O). The Ni-Ni separations in these complexes range from 6.84 to 6.48 A. The Ni-Ni, Ni-Ln and Ln-O phenolate bond distances in 2-12 show a gradual reduction proceeding from 2 to 12 in accordance with lanthanide contraction. Whereas all of the compounds (2-12) are paramagnetic systems, 8 displays a remarkable ST=(11)/2 ground state induced by an intramolecular Ni. . .Gd ferromagnetic interaction, and 10 is a new mixed metal 3d/4f single-molecule magnet generated by the high-spin ground state of the complex and the magnetic anisotropy brought by the dysprosium(III) metal ion. 相似文献
133.
P. Chandrasekhar Reddy Chakrapani B. Rangamannar 《Journal of Radioanalytical and Nuclear Chemistry》1992,165(1):57-60
A radiochemical displacement method has been developed for the determination of 10 g amounts of iron and antimony. The effect of pH and various foreign ions on the displacement of tracer60Co from labeled Co-o-Hydroxybenzaldehyde isonicotinoyl hydrazone (BIH) complex in isoamyl alcohol by iron and antimony was studied. 相似文献
134.
The solubilities of two fatty acids, namely hexadecanoic acid (palmitic acid) and octadecanoic acid (stearic acid) in supercritical carbon dioxide (SCCO2), were determined at T = (328 and 338) K from 12.8 MPa to 22.6 MPa. Three models, namely a thermodynamic model based on the Peng–Robinson equation of state with Kwak and Mansoori mixing rules, a model based on dilute solution theory proposed by Mendez-Santiago and Teja and a new reformulated Chrastil equation model, were used to correlate the solubilities. In all the models, the correlation constants are temperature independent. All the models successfully correlated the experimental results for the solubilities of hexadecanoic acid within 3%. 相似文献
135.
Wilfred F. van Gunsteren Dirk Bakowies Riccardo Baron Indira Chandrasekhar Markus Christen Xavier Daura Peter Gee Daan P. Geerke Alice Glttli Philippe H. Hünenberger Mika A. Kastenholz Chris Oostenbrink Merijn Schenk Daniel Trzesniak Nico F. A. van der Vegt Haibo B. Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2006,118(25):4168-4198
136.
Avijit Maiti Jessica Stubbe Dr. Nicolás I. Neuman Dr. Pankaj Kalita Prakash Duari Prof. Dr. Carola Schulzke Prof. Dr. Vadapalli Chandrasekhar Prof. Dr. Biprajit Sarkar Dr. Anukul Jana 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(17):6795-6800
Diradicals have been of tremendous interest for over a century ever since the first reports of p- and m-phenylene-bridged diphenylmethylradicals in 1904 by Thiele and 1915 by Schlenk. Reported here are the first examples of cyclic(alkyl)(amino)carbene (CAAC) analogues of Thiele's hydrocarbon, a Kekulé diradical, and Schlenk's hydrocarbon, a non-Kekulé diradical, without using CAAC as a precursor. The CAAC analogue of Thiele's hydrocarbon has a singlet ground state, whereas the CAAC analogue of Schlenk's hydrocarbon contains two unpaired electrons. The latter forms a dimer, by an intermolecular double head-to-tail dimerization. This straightforward synthetic methodology is modular and can be extended for the generation of redox-active organic compounds. 相似文献
137.
Ratna Surya Alwi Ramakrishnan Gopinathan Avijit Bhowal Chandrasekhar Garlapati 《Molecules (Basel, Switzerland)》2020,25(24)
The adsorption response of eosin Y and indigo carmine acid dyes on activated carbon as a function of system temperature for a fixed concentration was investigated at various temperatures via adsorption isotherms and their thermodynamic quantities such as enthalpy, entropy, and Gibbs free energy changes. The adsorption data were exploited to develop a new adsorption isotherm. The new isotherm was developed with the spirit of solid–liquid phase equilibrium and regular solution theory. The proposed model has four adjustable constants and correlates adsorption isotherm in terms of the system temperature and melting temperature of the dye. The effect of pH on the removal of acid dyes was reported. The pH variation was observed to affect the adsorption efficiency. The removal of eosin Y and indigo carmine decreased from 99.4% to 82.6% and 92.38% to 79.48%, respectively, when the pH of the solution varied from 2 to 12. The thermodynamic analysis of the process reveals that the process of the removal of acid dyes is exothermic and spontaneous. Moreover, the kinetics parameters of the batch process are reported. 相似文献
138.
S.P. Vinay Udayabhanu H.N. Sumedha G. Nagaraju S. Harishkumar N. Chandrasekhar 《应用有机金属化学》2020,34(10):e5830
Silver oxide nanoparticles (Ag2O NPs) were prepared using cantaloupe (Cucumis melo) seeds as a fuel by employing a green synthesis method. The prepared Ag2O NPs were investigated using powder X-ray diffraction (PXRD), UV–visible spectrum, Fourier transform infrared analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy-dispersive spectroscopy, and photoluminescence studies. PXRD data reveal the establishment of cubic crystal structure of Ag2O NPs. According to SEM and TEM results, the morphology of the prepared NPs was agglomerated and spherical. The photodegradation activity of the prepared Ag2O NPs over methylene blue dye was promising under visible light irradiation. Furthermore, the antimicrobial assay of the synthesized Ag2O NPs was carried out by the disc diffusion method against Gram-positive and Gram-negative microbial strains. 相似文献
139.
Srivari Chandrasekhar Birudaraju Saritha Police Naresh Marelli Udayakiran Chada Raji Reddy Bharatam Jagadeesh 《Helvetica chimica acta》2008,91(7):1267-1276
The conformational control of a 14‐helix nucleating template, cis‐β‐furanoid sugar amino acid (FSAA), over a flexible δ‐amino acid, ornithine is studied in a FSAA‐ornithine cyclic tetrapeptide. Extensive NMR and MD studies reveal that the cyclic peptide adopts a three‐dimentional bowl‐shape cavity, which promotes six‐ and seven‐membered intra‐ and inter‐residue H‐bonding, in polar and non‐polar solvents, respectively. 相似文献