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11.
Asmita Mukherjee R. Basu H. Dahiya L. Gamberg R. Godbole S. Gupta M. C. Kumar L. Magnea P. Mathews N. Mathur A. Mukherjee P. J. Mulders V. Ravindran A. Tripathi 《Pramana》2009,72(1):277-283
This is the report of the QCD working sub-group at the Tenth Workshop on High Energy Physics Phenomenology (WHEPP-X).
相似文献
12.
The upsurge interest in the development of efficient methodologies for the construction of nitrogen‐containing frameworks via the use of expedient reagents have been creating a renaissance in contemporary organic chemistry. In this perspective, tertbutyl nitrite (TBN) is an emerging building block. Due to its unique structural features, it shows differential reactivity under different reaction conditions. These diverse reactivities have resulted in the construction of a diverse array of complex N‐containing molecules. The primary objective of the present review is to bring the latest findings of TBN in terms of its applications in reactions (oxidation, diazotization, nitrosation, nitration, oximation, N‐synthon, and miscellaneous reactions) into the limelight. For simplicity and brevity, reactions in each section are explained with the mechanism of formation and selected examples are given. 相似文献
13.
14.
Grant J. Sherborne Avetik G. Gevondian Ignacio Funes‐Ardoiz Amit Dahiya Christoph Fricke Franziska Schoenebeck 《Angewandte Chemie (International ed. in English)》2020,59(36):15543-15548
Selective C –C couplings are powerful strategies for the rapid and programmable construction of bi‐ or multiaryls. To this end, the next frontier of synthetic modularity will likely arise from harnessing the coupling space that is orthogonal to the powerful Pd‐catalyzed coupling regime. This report details the realization of this concept and presents the fully selective arylation of aryl germanes (which are inert under Pd0/PdII catalysis) in the presence of the valuable functionalities C?BPin, C?SiMe3, C?I, C?Br, C?Cl, which in turn offer versatile opportunities for diversification. The protocol makes use of visible light activation combined with gold catalysis, which facilitates the selective coupling of C?Ge with aryl diazonium salts. Contrary to previous light‐/gold‐catalyzed couplings of Ar–N2+, which were specialized in Ar–N2+ scope, we present conditions to efficiently couple electron‐rich, electron‐poor, heterocyclic and sterically hindered aryl diazonium salts. Our computational data suggest that while electron‐poor Ar–N2+ salts are readily activated by gold under blue‐light irradiation, there is a competing dissociative deactivation pathway for excited electron‐rich Ar–N2+, which requires an alternative photo‐redox approach to enable productive couplings. 相似文献
15.
In a solvent-free system, Oxone on wet alumina oxidizes a variety of benzoins under the influence of microwaves. This rapid method circumvents the solubility limitations of Oxone in organic solvents and its use in solvents that may not be compatible at elevated temperatures. 相似文献
16.
This paper extends the work of Lewin et al., which showed that high levels of flame retardancy could be conferred on polyamide 6 (PA6) in the presence of small concentrations of ammonium sulphamate (AS) and dipentaerythritol (DP). PA6 samples were compounded with similarly low concentrations (2.5%w/w AS and 1%w/w DP) with or without nanoclays and fumed silica present at 1 and 2%w/w levels. Compounded samples were characterized by X‐ray diffraction, thermal analysis (differential thermal analysis/thermogravimetric analysis) and Fourier transform infrared. Flammability properties were measured by UL‐94, limiting oxygen index (LOI) and cone calorimetry test methods. All PA6 blended samples with or without nanoparticles were found to be V‐2 rated which differed from the results reported by Lewin et al. for similar samples where V‐0 ratings were obtained for clay‐free samples. LOI increases promoted by the inclusion of AS and DP alone were slightly reduced following the addition of all nanoparticles with the functionalized clays showing the largest effect. Introduction of silica, however, had the smallest effect in reducing LOI. Cone calorimetric results showed that while the presence of AS and DP raise peak heat release rate values with respect to PA6, addition of nanoparticles reduced values to below that for pure PA6. These reductions are dependent on nanoparticle concentration although differences between them, within experimental error, are very similar. While smoke generation is little affected by addition of AS and DP, the presence of nanoparticles promotes a slight increase. Results were interpreted in terms of previously published mechanisms for PA6‐AS‐DP thermal degradation and nanoparticle‐polymer interactions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
17.
A solid state method for the oxidation of thiols is described that uses benign oxidant, ammonium persulfate. 相似文献
18.
Alkyl, aryl and cyclic sulfides are rapidly oxidized to the corresponding sulfoxides in high yields upon microwave thermolysis with iron(III) nitrate impregnated on clay (clayfen) under solvent-free conditions; the conversion also occurs in refluxing methylene chloride but requires much longer reaction time. 相似文献
19.
Kalpana Dahiya Surjeet Kaur Suneja Vanita Verma 《Computational Optimization and Applications》2007,36(1):67-82
In this paper a minimization problem with convex objective function subject to a separable convex inequality constraint “≤”
and bounded variables (box constraints) is considered. We propose an iterative algorithm for solving this problem based on
line search and convergence of this algorithm is proved. At each iteration, a separable convex programming problem with the
same constraint set is solved using Karush-Kuhn-Tucker conditions. Convex minimization problems subject to linear equality/
linear inequality “≥” constraint and bounds on the variables are also considered. Numerical illustration is included in support
of theory. 相似文献
20.
Motivated by dead-mileage problem assessed in terms of running empty buses from various depots to starting points, we consider a class of the capacitated transportation problems with bounds on total availabilities at sources and total destination requirements. It is often difficult to solve such problems and the present paper establishes their equivalence with a balanced capacitated transportation problem which can be easily solved by existing methods. Sometimes, total flow in transportation problem is also specified by some external decision maker because of budget/political consideration and optimal solution of such problem is of practical interest to the decision maker and has motivated us to discuss such problem. Various situations arising in unbalanced capacitated transportation problems have been discussed in the present paper as a particular case of original problem. In addition, we have discussed paradoxical situation in a balanced capacitated transportation problem and have obtained the paradoxical solution by solving one of the unbalanced problems. Numerical illustrations are included in support of theory. 相似文献