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321.
Satish D Joglekar 《Pramana》1990,34(2):91-101
A self-contained argument is given for the mass independence of the renormalization constants in the minimal subtraction scheme
in dimensional regularization in a two mass theory (Yukawa theory). An extension to a theory containing more mass parameters
seems straightforward. 相似文献
322.
Indoles 1a-f and carbazoles 3a-c on treatment with ammonium thiocyanate on montmorillonite K10 clay at 80°C furnished the corresponding 3-thiocyanato derivatives 2a-f and 4a-c in good to high yields. Skatole 5 furnished the dimeric oxindole 6, which resulted from autoxidation. 相似文献
323.
Satish D. Joglekar Bhabani Prasad Mandai 《Zeitschrift fur Physik C Particles and Fields》1997,74(1):179-183
We consider a certain local generalization of BRS transformations of Yang-Mills theory in which the anti-commuting parameter is space time dependent. While these are not exact symmetries, they do lead to a new nontrivial WT identity. We make a precise connection between the “local BRS” and the broken orthosymplectic symmetry recently found in superspace formulation of Yang-Mills theory by showing that the local BRS WT identity is precisely the WT identity obtained in the superspace formulation via a superrotation. This “local BRS” WT identity could lead to new consequences not contained in the usual BRS WT identity. 相似文献
324.
Prafulla Joglekar Q. B. Chung Madjid Tavana 《Journal of Applied Mathematics and Decision Sciences》2001,5(4):253-268
Over the last three decades, numerous algorithms have been proposed to solve the work-cell formation problem. For practicing manufacturing managers it would be nice to know as to which algorithm would be most effective and efficient for their specific situation. While several studies have attempted to fulfill this need, most have not resulted in any definitive recommendations and a better methodology of evaluation of cell formation algorithms is urgently needed. Prima facie, the methodology underlying Miltenburg and Zhang's (M&Z) (1991) evaluation of nine well-known cell formation algorithms seems very promising. The primary performance measure proposed by M&Z effectively captures the objectives of a good solution to a cell formation problem and is worthy of use in future studies. Unfortunately, a critical review of M&Z's methodology also reveals certain important flaws in M&Z's methodology. For example, M&Z may not have duplicated each algorithm precisely as the developer(s) of that algorithm intended. Second, M&Z's misrepresent Chandrasekharan and Rajagopalan's [C&R's] (1986) grouping efficiency measure. Third, M&Z's secondary performance measures lead them to unnecessarily ambivalent results. Fourth, several of M&Z's empirical conclusions can be theoretically deduced. It is hoped that future evaluations of cell formation algorithms will benefit from both the strengths and weaknesses of M&Z's work. 相似文献
325.
326.
Elegbede AI Haldar MK Manokaran S Mallik S Srivastava DK 《Chemical communications (Cambridge, England)》2007,(43):4495-4497
We report the selective recognition of carbonic anhydrase isozymes based on the excited-state lifetimes of chelated Eu(3+) ions incorporated in polymerized liposomes. 相似文献
327.
Chemical investigation of the gum resin of Ferula assa-foetida L. resulted in the isolation of a new sesquiterpenoid coumarin, 7-(((E)-5-((1S,3S,6S)-3,6-dihydroxy-2,2,6-trimethylcyclohexyl)-3-methylpent-2-en-1-yl)oxy)-2H-chromen-2-one (asimafoetidnol), together with several other known compounds. The structure of asimafoetidnol was established on the basis of spectroscopic analyses. Geometry optimization of the compound has been carried out using a DFT/B3LYP/3-21G* method. 相似文献
328.
The photophysical behavior of acridine (Acr) shows facilitated water-assisted protonation equilibrium between its deprotonted (Acr* ~ 10 ns) and protonated forms (AcrH(+*) ~ 28 ns) within confined region of ordered water molecules inside AOT/H(2)O/n-heptane reverse micelles (RMs). The time-resolved-area-normalized-emission spectra confirm both Acr* and AcrH(+*), while time-resolved-emission spectra depict time evolution between them. Quenching of AcrH(+*) with N,N-dimethylaniline (DMA) is a purely diffusion-controlled bimolecular quenching with linear Stern-Volmer (S-V) plot, while nonlinearity arises with triethylamine (TEA) that forms ground state complex with AcrH(+) (AcrH(+)··H(2)O··TEA) indicating both static and dynamic quenching. Transient intermediates, DMA(?+) and AcrH(?) infer photoinduced electron transfer from DMA to Acr, while those from AcrH(+)··H(2)O··TEA complex suggest water mediated excited-state proton transfer (ESPT) between AcrH(+) and TEA. The ESPT becomes faster in larger RMs due to enhanced mobility of hydronium ions in AcrH(+)··H(2)O··TEA, which reduces in smaller RMs as water becomes much more constrained owing to stronger complexation by excess confinement. 相似文献
329.
The solvatochromic properties of saturated β-diketones (dk) are largely dependent on the nature of 1- and 3-aryl substituents. The photophysical properties of four such different diketones (dk 1-4) are studied in a small variety of solvents. For all these diketones intramolecular charge transfer (ICT) take place along with the intermolecular one depending upon the 1,3-diaryl substituents. Formation of isosbestic among the diketones and Mg2+ are well established in the ground state while for excited state these are much labile. The binding energies also vary with the aryl substitution. 相似文献
330.