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131.
Rathore N. S. Pabby Anil Kumar Venugopalan A. K. 《Journal of Radioanalytical and Nuclear Chemistry》2004,262(3):543-549
Hydrated iron oxide or amorphous-Fe2O3·3.5 H2O (HFeO), hydrated titanium oxide (HTiO) and hydrated thorium oxide (HThO) were synthesized and their applicability for the decontamination of intermediate level liquid wastes (ILLW) was tested. The sorption of a few actinides like plutonium and americium on HFeO, 137Cs and 106Ru on HTiO and 90Sr on HThO was investigated as a function of pH, time and loading capacity of the hydrous oxide with metal ions. The influence of the total dissolved salt content was also monitored. Some of these parameters influenced the sorption behavior significantly. The radiation stability of these inorganic sorbents were studied by irradiating them up to 48 Mrad. Adsorbed actinides and fission products were successfully eluted from HFeO and from the mix-bed of HTiO and HThO by 0.5M nitric acid.The authors wish to thank Shri R. D. Changarani, Chief Superintendent NRG Facilities and Shri P. K. Dey, Head FRD for their valuable advice and constant support. 相似文献
132.
Anil Kumar PG Pregosin PS Schmid TM Consiglio G 《Magnetic resonance in chemistry : MRC》2004,42(9):795-800
Three new salts of Rh(I), [Rh(1,5-COD)(Biphemp)]X, Biphemp = (6,6'-dimethylbiphenyl-2,2'-diyl)bis(diphenylphosphine), X = BF4-, 2a, PF6-, 2b, and CF3SO3-, 2c, were prepared and studied using PGSE diffusion, 1H-19F HOESY and inverse 103Rh (amongst other) NMR methods. Although the immediate coordination sphere of the cation does not sense the change in the anion, the PGSE diffusion and 1H-19F HOESY data suggest that, in addition to some ion pairing, each of the anions in 2 demonstrates selectivity in its approach towards the cation. 相似文献
133.
Kishore Kumar Sankara Layne T. Watson 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1985,36(6):845-853
Summary This paper studies the flow of an incompressible, constant density micropolar fluid past a stretching sheet. The governing boundary layer equations of the flow are solved numerically using a globally convergent homotopy method in conjunction with a least change secant update quasi-Newton algorithm. The flow pattern depends on three non-dimensional parameters. Some interesting results are illustrated graphically and discussed.
This work performed at Sandia National Laboratories supported by the U. S. Department of Energy under contract number DE-AC04-76DP00789. 相似文献
Résumé Nous étudions l'écoulement d'un fluid micropolaire et incompressible, de densité constante, le long d'une surface qui l'étend. Les équations de la couche limite qui régissent l'écoulement sont résolues numériquement. On utilise un algorithme quasi-Newtonien de type least change secant update avec une méthode homotopique /`a convergence globale. Certains résultats intéressants sont discutés et illustrés graphiquement.
This work performed at Sandia National Laboratories supported by the U. S. Department of Energy under contract number DE-AC04-76DP00789. 相似文献
134.
Summary 3,4-Dicyano-5-aminopyrazole, H3,4(CN)25NH2pz (L) reacts either with anhydrous MCl2 or with [M(PPh3)2Cl2] to yield ML4Cl2 complexes (M = Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd or Hg), whose monomeric and covalent natures have been confirmed by their solubility in most non-polar solvents and their low electrical conductivities. The bonding mode of substituted pyrazole is inferred from the position of the (C-N) band in the i.r. spectra. The electronic spectra and the magnetic moments of these compounds were recorded. 相似文献
135.
Syed Mashhood Ali Santosh Kumar Upadhyay Arti Maheshwari Mamoru Koketsu 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(3-4):325-328
1H NMR spectroscopic study of fluvastatin sodium (FLU), β-Cyclodextrin (β-CD) and their mixtures confirmed the formation of FLU/β-CD inclusion complex in solution. The stoichiometry of the complex was determined to be 1:1 and the overall binding constant (K
s) was calculated to be 340 M−1. Two dimensional COSY, ROESY and DEPTO experiments were performed for the unambiguous assignment of aromatic proton resonances and it was found that two isomeric forms of FLU are present in solution. It was confirmed with the help of ROESY spectral data that only F-substituted aromatic ring penetrates the β-CD cavity and there is chiral differentiation by the β-CD as one of the isomer binds more strongly, which is indicated by the intensity of correlation peaks. The mode of penetration of the guest into the β-CD cavity was also established and structure of the complex has been proposed. 相似文献
136.
Kumar K Michalik D Garcia Castro I Tillack A Zapf A Arlt M Heinrich T Böttcher H Beller M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(3):746-757
A practical route for the synthesis of new biologically active 5-HT(2 A) receptor antagonists has been developed. In only three catalytic steps, this class of central nervous system (CNS) active compounds can be synthesized efficiently with high diversity. As the initial step, an anti-Markovnikov addition of amines to styrenes provides an easy route to N-(arylalkyl)piperazines, which constitute the core structure of the active molecules. Here, base-catalyzed hydroamination reactions of styrenes with benzylated piperazine proceeded in high yield even at room temperature. After catalytic debenzylation, the free amines were successfully carbonylated with different aromatic and heteroaromatic halides and carbon monoxide to yield the desired compounds in good to excellent yields. The two key reactions, base-catalyzed hydroamination of styrenes and palladium-catalyzed aminocarbonylation of haloarenes/heterocycles, showed tolerance towards various functional groups, thereby demonstrating the potential to synthesize a wide variety of new derivatives of this promising class of pharmaceuticals. 相似文献
137.
Y.C. Sunil Kumar 《Tetrahedron letters》2007,48(26):4565-4568
2-(1-Methyl-1,2,5,6-tetrahydropyridin-3-yl)morpholine is useful for synthesizing potent antimicrobials including the arecoline derivatives, phendimetrazine and polygonapholine and was synthesised in nine steps with an overall yield of 36%. Bromination of 3-acetylpyridine and dehydration of a diol with cyclization were pivotal to the success of the strategy. 相似文献
138.
Tapan Kumar Sengupta 《Journal of polymer science. Part A, Polymer chemistry》1989,27(6):2065-2070
In the complete absence of a systematic polymer nomenclature, a scheme of nomenclature based on structure is proposed. The problem of naming a “mer” has been solved for an addition polymer by adding “ne” to the monomer name, the justification being on withdrawal of a π bond a monomer becomes a mer. To furnish completeness to the nomenclature, condensation polymers were included in the system. The present nomenclature system of polymers is very arbitrary. Some polymers are not chemically named, some named incorrectly, and there are some fantastic names. After pointing these out, the possible solutions were shown, encompassing a systematic discussion on nearly every type of polymer–linear, branched, or crosslinked–and copolymer (including block or graft), and plastic, fiber, or rubber, and stereospecific polymer. One or more names were proposed for different cases. 相似文献
139.
N. S. Rathore Anil Kumar Pabby A. K. Venugopalan 《Journal of Radioanalytical and Nuclear Chemistry》2005,262(3):543-549
Hydrated iron oxide or amorphous-Fe2O3·3.5 H2O (HFeO), hydrated titanium oxide (HTiO) and hydrated thorium oxide (HThO) were synthesized and their applicability for the decontamination of intermediate level liquid wastes (ILLW) was tested. The sorption of a few actinides like plutonium and americium on HFeO, 137Cs and 106Ru on HTiO and 90Sr on HThO was investigated as a function of pH, time and loading capacity of the hydrous oxide with metal ions. The influence of the total dissolved salt content was also monitored. Some of these parameters influenced the sorption behavior significantly. The radiation stability of these inorganic sorbents were studied by irradiating them up to 48 Mrad. Adsorbed actinides and fission products were successfully eluted from HFeO and from the mix-bed of HTiO and HThO by 0.5M nitric acid.The authors wish to thank Shri R. D. Changarani, Chief Superintendent NRG Facilities and Shri P. K. Dey, Head FRD for their valuable advice and constant support. 相似文献
140.
Richard A. Bartsch David A. Babb Bronislaw P. Czech Dhimant H. Desai Eddy Chapoteau Carl R. Gebauer Wolodymyr Zazulak Anad Kumar 《Journal of inclusion phenomena and macrocyclic chemistry》1990,9(2):113-123
Four novel chromogenic benzocryptands and one side-armed chromogenic cryptand have been synthesized and their complexing abilities for alkali metal cations are described. 相似文献