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131.
We investigate the generalized Quantum Chromodynamics (QCD) ghost model of dark energy in the framework of Einstein gravity. First, we study the non-interacting generalized ghost dark energy in a flat Friedmann-Robertson-Walker (FRW) background. We obtain the equation of state parameter, w D = p/ρ, the deceleration parameter, and the evolution equation of the generalized ghost dark energy. We find that, in this case, w D cannot cross the phantom line (w D > ?1) and eventually the universe approaches a de-Sitter phase of expansion (w D → ?1). Then, we extend the study to the interacting ghost dark energy in both a flat and non-flat FRW universe. We find that the equation of state parameter of the interacting generalized ghost dark energy can cross the phantom line (w D < ?1) provided the parameters of the model are chosen suitably. Finally, we constrain the model parameters by using the Markov Chain Monte Carlo (MCMC) method and a combined dataset of SNIa, CMB, BAO and X-ray gas mass fraction.  相似文献   
132.
133.
This paper deals with the diffusion approximation of a semiconductor Boltzmann–Poisson system. The statistics of collisions we are considering here, is the Fermi–Dirac operator with the Pauli exclusion term and without the detailed balance principle. Our study generalizes, the result of Goudon and Mellet [11 Goudon , T. , Mellet , A. ( 2003 ). On fluid limit for the semiconductors Boltzmann equation . J. Diff. Eqs. 189 : 1745 . [Google Scholar]], to the multi-dimensional case.  相似文献   
134.
The tricyclic isatin, 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione, undergoes three‐component, one‐pot reactions with 1‐aryl‐3‐methylpyrazole‐5‐amines and cyclohexane‐1,3‐diones producing hexacyclic spiro products, hexahydrospiro[pyrazolo[3,4‐b]quinoline‐4,1‐pyrrolo[3,2,1‐ij]quinoline‐2′,5(1H,4′H)‐diones]. Comparable spiro condensation products are also obtained using 4‐hydroxy‐2H‐1‐benzopyran‐2‐one in place of cyclohexane‐1,3‐diones.  相似文献   
135.
A new, fast, and easy one‐pot cyclopropanation reaction of aromatic and aliphatic aldehydes with 1H‐indene‐1,3(2H)‐dione and cyanogen bromide (BrCN) was developed for synthesizing 3′‐(aryl[alkyl])‐dispiro[indan‐2,1′‐cyclopropane‐2′,2′′‐indan]‐1,1′′,3,3′′‐tetrone in excellent yields in a short time (about 15 s) under basic media. All structures were characterized using IR, 1H NMR, and 13C NMR spectroscopy techniques.  相似文献   
136.
Research on Chemical Intermediates - Photocatalysis using semiconductors has emerged as a promising wastewater treatment process to overcome the major challenges faced by conventional technologies....  相似文献   
137.
The thermophoretic motion of a charged spherical colloidal particle and its accompanying cloud of counterions and coions in a temperature gradient is studied theoretically. Using the Debye-Hückel approximation, the Soret drift velocity of a weakly charged colloid is calculated analytically. For highly charged colloids, the nonlinear system of electrokinetic equations is solved numerically, and the effects of high surface potential, dielectrophoresis, and convection are examined. Our results are in good agreement with some of the recent experiments on highly charged colloids without using adjustable parameters.  相似文献   
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139.
Research on Chemical Intermediates - An efficient solid/slurry-state synthesis of arylidene and alkylidene malonates as versatile intermediates is developed in the presence of mesoporous...  相似文献   
140.
We present two Penning trap experiments concerned with different aspects of the physics of extreme electromagnetic fields, the ARTEMIS experiment designed for bound-electron magnetic moment measurements in the presence of the extremely strong fields close to the nucleus of highly charged ions, and the HILITE experiment, in which well-defined ion targets are to be subjected to high-intensity laser fields.  相似文献   
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