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61.
Frank Merle 《纯数学与应用数学通讯》1996,49(8):765-794
We consider the blowup solution ( u,n,v )( t ) of the Zakharov equations where u : R 2 → C, n : R 2 → R, v: R2 → R2 in the energy space H1 = {(u,n,v) η H1 × L2 × L2}. We show that there is a constant c depending on the L2-norm of u0 such that where T is the blowup time. We check that this estimate is optimal and give further applications. © 1996 John Wiley & Sons, Inc. 相似文献
62.
Adisorn Adulpravitchai Manfred Lindner Alexander Merle Rabindra N. Mohapatra 《Physics letters. [Part B]》2009,680(5):476-479
We discuss a one loop model for neutrino masses which leads to a seesaw-like formula with the difference that the charged lepton masses replace the unknown Dirac mass matrix present in the usual seesaw case. This is a considerable reduction of parameters in the neutrino sector and predicts a strong hierarchical pattern in the right handed neutrino mass matrix that is easily derived from a U(1)H family symmetry. The model is based on the left–right gauge group with an additional Z4 discrete symmetry which gives vanishing neutrino Dirac masses and finite Majorana masses arising at the one loop level. Furthermore, it is one of the few models that naturally allow for large (but not necessarily maximal) mixing angles in the lepton sector. A generalization of the model to the quark sector requires three iso-spin singlet vector-like down type quarks, as in E6. The model predicts an inert doublet type scalar dark matter. 相似文献
63.
Therrien E Englebienne P Arrowsmith AG Mendoza-Sanchez R Corbeil CR Weill N Campagna-Slater V Moitessier N 《Journal of chemical information and modeling》2012,52(1):210-224
As part of a large medicinal chemistry program, we wish to develop novel selective estrogen receptor modulators (SERMs) as potential breast cancer treatments using a combination of experimental and computational approaches. However, one of the remaining difficulties nowadays is to fully integrate computational (i.e., virtual, theoretical) and medicinal (i.e., experimental, intuitive) chemistry to take advantage of the full potential of both. For this purpose, we have developed a Web-based platform, Forecaster, and a number of programs (e.g., Prepare, React, Select) with the aim of combining computational chemistry and medicinal chemistry expertise to facilitate drug discovery and development and more specifically to integrate synthesis into computer-aided drug design. In our quest for potent SERMs, this platform was used to build virtual combinatorial libraries, filter and extract a highly diverse library from the NCI database, and dock them to the estrogen receptor (ER), with all of these steps being fully automated by computational chemists for use by medicinal chemists. As a result, virtual screening of a diverse library seeded with active compounds followed by a search for analogs yielded an enrichment factor of 129, with 98% of the seeded active compounds recovered, while the screening of a designed virtual combinatorial library including known actives yielded an area under the receiver operating characteristic (AU-ROC) of 0.78. The lead optimization proved less successful, further demonstrating the challenge to simulate structure activity relationship studies. 相似文献
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Arrowsmith M Hadlington TJ Hill MS Kociok-Köhn G 《Chemical communications (Cambridge, England)》2012,48(38):4567-4569
The heteroleptic magnesium alkyl complex [CH{C(Me)NAr}(2)Mg(n)Bu] (Ar = 2,6-(i)Pr(2)C(6)H(3)) is reported as a highly efficient pre-catalyst for the hydroboration of aldehydes and ketones with pinacolborane. 相似文献
66.
Jrmie Chicheportiche Xavier Merle Xavier Gloerfelt Jean-Christophe Robinet 《Comptes Rendus Mecanique》2008,336(7):586-591
The first bifurcation in a lid-driven cavity characterized by three-dimensional Taylor–Görtler-Like instabilities is investigated for a cubical cavity with spanwise periodic boundary conditions at Re=1000. The modes predicted by a global linear stability analysis are compared to the results of a direct numerical simulation. The amplification rate, and the shape of the three-dimensional perturbation fields from the direct numerical simulation are in very good agreement with the characteristics of the steady S1 mode from the stability analysis, showing that this mode dominates the other unstable unsteady modes. To cite this article: J. Chicheportiche et al., C. R. Mecanique 336 (2008). 相似文献
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K. I. Blomqvist W. U. Boeglin R. Böhm M. Distler D. Drechsel R. Edelhoff J. Friedrich R. Geiges O. Hanstein M. Kahrau M. Korn H. Kramer K. W. Krygier V. Kunde M. Kuss A. Liesenfeld K. Merle R. Neuhausen E. A. J. M. Offermann Th. Pospischil M. Potokar A. Rokavec A. W. Richter G. Rosner P. Sauer S. Schardt H. Schmieden S. Sirca L. Tiator B. Vodenik A. Wagner Th. Walcher S. Wolf 《Zeitschrift für Physik A Hadrons and Nuclei》1996,353(4):415-421
The reactione+p →> e+π ++n at c.m. energyW=1125MeV and momentum transfer Q2=0.117GeV2/c2 has been measured. The transverse and longitudinal structure functions have been separated by varying the polarization of the virtual photon (Rosenbluth plot) with a 3 to 4% error. In addition the longitudinal-transverse interference term has been determined measuring the right-left asymmetry with an accuracy of 3%. The experimental data are compared to model calculations, and the sensitivity of the results to the axial and pion formfactors is discussed. 相似文献
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