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981.
Ricardo José Alves Joaquin Isac Garcia Alain Olesker Gabor Lukacs 《Journal of carbohydrate chemistry》2013,32(3):655-659
Abstract Using well-established methodology, D-glucose was transformed into a tribenzoyloxy cyclohexanone oxime derivative. Sodium azide treatment permitted the regiospecific exchange of the benzoyloxy group at a α-position relative to ketone oxime. Under standard Beckmann conditions the α-azido was oxime cleaved to provide an ω-dicyano compound. 相似文献
982.
Jonas Croissant Dr. Marie Maynadier Audrey Gallud Dr. Harmel Peindy N'Dongo Dr. Jeff L. Nyalosaso Dr. Gaëlle Derrien Dr. Clarence Charnay Dr. Jean‐Olivier Durand Dr. Laurence Raehm Prof. Françoise Serein‐Spirau Dr. Nathalie Cheminet Dr. Thibaut Jarrosson Dr. Olivier Mongin Dr. Mireille Blanchard‐Desce Dr. Magali Gary‐Bobo Dr. Marcel Garcia Dr. Jie Lu Prof. Fuyuhiko Tamanoi Dr. Derrick Tarn Tania M. Guardado‐Alvarez Prof. Jeffrey I. Zink 《Angewandte Chemie (International ed. in English)》2013,52(51):13813-13817
983.
984.
985.
986.
Norberto Garcia‐Cairasco Miguel Moyses‐Neto Flavio DelVecchio Jos A. C. Oliveira Francisco L. dosSantos Olagide W. Castro Gabriel M. Arisi Mrcio Dantas Ruither O. G. Carolino Joaquim Coutinho‐Netto Andre L. A. Dagostin Marcelo C. A. Rodrigues Ricardo M. Leo Samir A. P. Quintiliano Luiz F. Silva Leonardo Gobbo‐Neto Norberto P. Lopes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(49):12981-12981
987.
988.
Salvador Garcia 《advances in applied mathematics and mechanics.》2009,1(4):546-572
The lid-driven square cavity flow is investigated by numerical
experiments. It is found that from $ \mathrm{Re} $$=$ $5,000 $ to $
\mathrm{Re}
$$=$$ 7,307.75 $ the solution is stationary, but at $
\mathrm{Re}$$=$$7,308 $ the solution is time periodic. So the
critical Reynolds number for the first Hopf bifurcation localizes
between $ \mathrm{Re} $$=$$ 7,307.75 $ and $ \mathrm{Re} $$=$$ 7,308
$. Time periodical behavior begins smoothly, imperceptibly at the
bottom left corner at a tiny tertiary vortex; all other vortices
stay still, and then it spreads to the three relevant corners of the
square cavity so that all small vortices at all levels move
periodically. The primary vortex stays still. At $ \mathrm{Re}
$$=$$ 13,393.5 $ the solution is time periodic; the long-term
integration carried out past $ t_{\infty} $$=$$ 126,562.5 $ and the
fluctuations of the kinetic energy look periodic except slight
defects. However, at $ \mathrm{Re} $$=$$ 13,393.75 $ the solution is
not time periodic anymore: losing unambiguously, abruptly time
periodicity, it becomes chaotic. So the critical Reynolds number for
the second Hopf bifurcation localizes between $ \mathrm{Re} $$=$$
13,393.5 $ and $ \mathrm{Re} $$=$$ 13,393.75 $. At high Reynolds
numbers $ \mathrm{Re} $$=$$ 20,000 $ until $ \mathrm{Re} $$=$$
30,000 $ the solution becomes chaotic. The long-term integration is
carried out past the long time $ t_{\infty} $$=$$ 150,000 $,
expecting the time asymptotic regime of the flow has been reached.
The distinctive feature of the flow is then the appearance of drops:
tiny portions of fluid produced by splitting of a secondary vortex,
becoming loose and then fading away or being absorbed by another
secondary vortex promptly. At $ \mathrm{Re}
$$=$$ 30,000 $ another phenomenon arises—the abrupt appearance at
the bottom left corner of a tiny secondary vortex, not produced by
splitting of a secondary vortex. 相似文献
989.
M.E. Garcia 《Applied Physics A: Materials Science & Processing》2001,72(3):261-271
A theoretical study of different ultrafast nonequilibrium processes taking place during and after ultrashort excitation of
clusters is presented. We discuss similarities and differences for several processes involving nonequilibrium ultrafast motion
of atoms and electrons. We study ultrashort relaxation of clusters in response to excitations produced by femtosecond laser
pulses of different intensities. We show how different relaxation processes, such as bond breaking, melting, fragmentation,
emission of atoms, or Coulomb explosion, can be induced, depending on the laser intensity and laser pulse duration. We also
discuss processes involving nonequilibrium electron dynamics, such as intraband Auger decay in clusters and ultrafast electronic
motion during collisions between clusters and surfaces. We show that this electron dynamics leads to Stückelberg-like oscillations
of measurable quantities, such as the electron emission yield.
Received: 4 April 2000 / Accepted: 6 November 2000 / Published online: 9 February 2001 相似文献