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131.
Summary The ligand, 4-methylimidazole L, reacts with Copper(II) to yield hexacoordinated and tetragonal complexes, CuL4X2 (X = Cl, Br, NO3, ClO4, NCS or 0.5 SO4) and CuL6(BF4)2; and tetracoordinated square-planar complexes, CuL2(N3)2, (CuL4)H9Cl4) and (Me4N)(CuLCl3). The complexes obtained were characterized on the basis of analytical data, i.r. and electronic spectra, conductance and magnetic susceptibility measurements. T.g.a, d.t.g and d.t.a studies have been made for some of the complexes which were found to decompose with loss of imidazole ligand. The stoichiometry of the thermal decompositions was determined. 相似文献
132.
Sanjay Kumar Saxena Archana Mukherjee Yogendra Kumar Ramu Ram A. S. Tapase Vivek J. Anand Ashutosh Dash 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1237-1243
‘Permanent seed implantation’ using 125I- seeds has emerged as an effective treatment modality for management of prostate cancer. An indigenous technology for the production of 125I brachytherapy sources (‘BARC 125I Ocu-Prosta seed’) has been developed. In this current work, we describe an overview of our experience on large scale production of 125I brachytherapy sources, their quality assessment, in vivo bio-evaluation and initial experience on their journey from bench to bed-side for the treatment of prostate cancer. 相似文献
133.
Oxidation kinetics of benzaldehyde and some of its ortho- and para-monosubstituted derivatives have been studied using cetylpicolinium dichromates, a class of novel phase transfer oxidants, in dichloromethane medium. The rate of reaction is first order with respect to oxidant and fractional order with respect to the substrates. The Michaelis–Menten type oxidation was observed with respect to the substrates. Benzaldehydes are found to be oxidized to their corresponding acids. The mechanism of oxidation reaction has been suggested based on the solvent isotope effect, Hammett plot, and thermodynamic study. The solvent isotope effect (kCHCl3/kCDCl3 = 1.57) indicates the involvement of hydrogen exchange with the medium during oxidation reactions. A strong influence of specific solute–solvent interactions on the rate of the reaction is observed. Both the electron-withdrawing and electron-releasing substituents on the substrates accelerate the rate of reaction. 相似文献
134.
Seema Yadav Ajeet Singh Isha Mishra Sriparna Ray Shaikh M. Mobin Chandrakanta Dash 《应用有机金属化学》2019,33(7)
Well‐defined and air‐stable PEPPSI (Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation) themed palladium bis‐N‐heterocyclic carbene complexes have been developed for the domino Sonogashira coupling/cyclization reaction of 2‐iodophenol with a variety of terminal alkynes and C‐H bond arylation of benzothiazole with aryl iodides. The PEPPSI themed palladium complexes, 2a and 2b were synthesized in good yields from the reaction of corresponding imidazolium salts with PdCl2 and K2CO3 in pyridine. The new air‐stable palladium‐NHC complexes were characterized by NMR spectroscopy, X‐ray crystallography, elemental analysis, and mass spectroscopy studies. The PEPPSI themed palladium(II) bis‐N‐heterocyclic carbene complexes 2a and 2b exhibited excellent catalytic activities for domino Sonogashira coupling/cyclization reaction of 2‐iodophenol with terminal alkynes yielding benzofuran derivatives. In addition, the palladium complexes, 2a and 2b successfully catalyzed the direct C‐H bond arylation of benzothiazole with aryl iodides as coupling partners in presence of CuI as co‐catalyst. 相似文献
135.
Devi Jai Pachwania Sushila Kumar Deepak Jindal Deepak Kumar Jan Suraya Dash Ashutosh K. 《Research on Chemical Intermediates》2022,48(1):267-289
Research on Chemical Intermediates - Organotin(IV) complexes are gaining major attention as drug candidates, accordingly we have synthesized a cluster of novel diorganotin(IV) complexes R2SnClL... 相似文献
136.
Journal of Solid State Electrochemistry - In the present paper, we have reported the standard molar Gibbs energy of formation for Li2CaThF8(s) measured by solid electrolyte galvanic cell technique... 相似文献
137.
This paper deals with a chance constrained programming model, where both fuzziness and randomness are present in the objective
function and constraints. The concept of fuzzy random variable, mean and variance of fuzzy random variable, minimum of fuzzy
numbers are used in the model. The methodology is verified through a numerical example. 相似文献
138.
In this paper we use facets of simple mixed-integer sets with three variables to derive a parametric family of valid inequalities
for general mixed-integer sets. We call these inequalities two-step MIR inequalities as they can be derived by applying the simple mixed-integer rounding (MIR) principle of Wolsey (1998) twice. The two-step
MIR inequalities define facets of the master cyclic group polyhedron of Gomory (1969). In addition, they dominate the strong
fractional cuts of Letchford and Lodi (2002). 相似文献
139.
140.
Journal of Solid State Electrochemistry - The fission product strontium (Sr), after generation in the reactor due to fission of 233U, might exist as SrF2 in the molten fluoride medium of molten... 相似文献