scholarly journals Efficient Spectral Methods for Quasi-Equilibrium Closure Approximations of Symmetric Problems on Unit Circle and Sphere

2021 ◽  
Vol 89 (2) ◽  
Author(s):  
Shan Jiang ◽  
Haijun Yu
2001 ◽  
Vol 11 (PR6) ◽  
pp. Pr6-151-Pr6-159 ◽  
Author(s):  
R. Guérin ◽  
M. El Ganaoui ◽  
P. Haldenwang ◽  
P. Bontoux

1999 ◽  
Vol 53 (9-10) ◽  
pp. 1-10
Author(s):  
V. A. Omel'chenko ◽  
V. V. Balabanov ◽  
B. M. Bezruk ◽  
Yu. N. Goloborod'ko

Author(s):  
V. A. Rumyantseva ◽  
◽  
V. V. Stuchilin ◽  
I. S. Svirin ◽  
S. Z. Shkundin ◽  
...  
Keyword(s):  

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Zena G. Alrecabi ◽  
Zainab Amer ◽  
Naeemah Al-Lami

This study including prepared new colored esters containing heterocyclic with high molecular weights. In the first part of work we synthesized azo dyes [1,2] from the reaction p-toluidine with β-naphthol and o-nitro phenol, thin we synthesized Schiff bases [3,4] by the reaction anthranilic acid with benzaldehyde and dimethyl benzaldehyde. The reaction azo dyes (contain OH group) with Schiff base (contain COOH group) these led to produce the new colored esters [A1-A4]. The second part of work was modification the (C=N-) group in esters to heterocyclic compounds by reacting with phenyl iso cyanide to produce new β-lactam [B1-B4] and with anthranilic acid to get new hydroquinazoline [C1-C4]. All these compounds were characterized by physical properties and spectral methods FTIR, 1H-NMR and 13C-NMR.


10.37236/1734 ◽  
2003 ◽  
Vol 10 (1) ◽  
Author(s):  
David Arthur

An arc-representation of a graph is a function mapping each vertex in the graph to an arc on the unit circle in such a way that adjacent vertices are mapped to intersecting arcs. The width of such a representation is the maximum number of arcs passing through a single point. The arc-width of a graph is defined to be the minimum width over all of its arc-representations. We extend the work of Barát and Hajnal on this subject and develop a generalization we call restricted arc-width. Our main results revolve around using this to bound arc-width from below and to examine the effect of several graph operations on arc-width. In particular, we completely describe the effect of disjoint unions and wedge sums while providing tight bounds on the effect of cones.


1986 ◽  
Vol 51 (2) ◽  
pp. 436-446 ◽  
Author(s):  
Ladislav Kohout ◽  
Vijay Kumar Sethi ◽  
Jaroslav Zajíček ◽  
Alexander Kasal

Acetolysis of 3-methanesulfonyloxy-7-benzoyloxy-5β,6β-cyclopropanocholestanes with various configurations in positions 3 and 7 is described and the products are assigned structure using spectral methods. The 7-substituted compounds show greater propensity to elimination reactions than the 7-unsubstituted ones.


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