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Jerry W MisnerJack W Fisher John P GardnerSteve W Pedersen Kristina L TrinkleBilly G Jackson Tony Y Zhang 《Tetrahedron letters》2003,44(32):5991-5993
The nucleus of the carbacephem antibiotic loracarbef was synthesized in a highly efficient and enantioselective fashion from 2S,3S-2-amino-3-hydroxy-6-heptenoic acid (AHHA), which was derived from enzyme-catalyzed condensation of glycine and 4-pentenaldehyde. The bicyclic framework of this compound was established through sequential Mitsunobu reaction and aldol condensations. 相似文献
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N. Jachowicz G. C. McLaughlin 《The European Physical Journal A - Hadrons and Nuclei》2006,29(1):43-47
We argue that isotropization and, consequently, thermalization of the system of gluons and quarks produced in an ultrarelativistic
heavy-ion collision does not follow from Feynman diagram analysis to any order in the coupling constant. We conclude that
the apparent thermalization of quarks and gluons, leading to success of perfect fluid hydrodynamics in describing heavy-ion
collisions at RHIC, can only be attributed to the non-perturbative QCD effects not captured by Feynman diagrams. We proceed
by modeling these non-pertrubative thermalization effects using viscous hydrodynamics. We point out that matching Color Glass
Condensate inital conditions with viscous hydrodynamics leads to a continuous evolution of all the components of the energy-momentum
tensor and, unlike the case of ideal hydrodynamics, does not give rise to a discontinuity in the longitudinal pressure. An
important consequence of such a matching is a relationship between the thermalization time and shear viscosity: we observe
that small viscosity leads to short thermalization time. 相似文献
129.
We report an intrinsically stable quantum key distribution scheme based on genuine frequency-coded quantum states. The qubits are efficiently processed without fiber interferometers by fully exploiting the nonlinear interaction occurring in electro-optic phase modulators. The system requires only integrated off-the-shelf devices and could be used with a true single-photon source. Preliminary experiments have been performed with weak laser pulses and have demonstrated the feasibility of this new setup. 相似文献
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Changshi Li Yuhui Liu Fengru Wang Jerry Zhijian Yang & Cheng Yuan 《高等学校计算数学学报(英文版)》2023,16(2):433-452
We proposed absorbing interface conditions for the simulation of linear
wave propagation on non-uniform meshes. Based on the superposition principle of
second-order linear wave equations, we decompose the interface condition problem into two subproblems around the interface: for the first one the conventional
artificial absorbing boundary conditions is applied, while for the second one, the
local analytic solutions can be derived. The proposed interface conditions permit
a two-way transmission of low-frequency waves across mesh interfaces which can
be supported by both coarse and fine meshes, and perform a one-way absorption
of high-frequency waves which can only be supported by fine meshes when they
travel from fine mesh regions to coarse ones. Numerical examples are presented to
illustrate the efficiency of the proposed absorbing interface conditions. 相似文献