Dynamical System of Scalar Field from 2-Dimension to 3-D and its Cosmological Implication

We give the three-dimensional dynamical autonomous systems for most of the popular scalar field dark energy models including (phantom) quintessence, (phantom) tachyon, k-essence and general non-canonical scalar field models, change the dynamical variables from variables $(x, y, \lambda)$ to observable related variables $(w_{\phi}, \Omega_{\phi}, \lambda)$, and show the intimate relationships between those scalar fields that the three-dimensional system of k-essence can reduce to (phantom) tachyon, general non-canonical scalar field can reduce to (phantom) quintessence and k-essence can also reduce to (phantom) quintessence for some special cases. For the applications of the three-dimensional dynamical systems, we investigate several special cases and give the exactly dynamical solutions in detail. In the end of this paper, we argue that, it is more convenient and also has more physical meaning to express the differential equations of dynamical systems in $(w_{\phi}, \Omega_{\phi}, \lambda)$ instead of variables $(x, y, \lambda)$ and to investigate the dynamical system in 3-Dimension instead of 2-Dimension. We also raise a question about the possibility of the chaotic behavior in the spatially flat single scalar field FRW cosmological models in the presence of ordinary matter.Comment: 20 pages, 8 figures,some references added. Minor changes according to the suggestions from referee

Active Methylene-based Multicomponent Reactions under Microwave Heating

The use of emerging multicomponent reactions (MCRs) in conjunction with microwave (MW)-assisted chemistry techniques is dramatically reducing chemical waste and reaction times in several organic syntheses and chemical transformations. MW-assisted active methylene-based multicomponent reactions serve as a rapid and efficient tool for the synthesis of versatile heterocycles, particularly those containing structural diversity and complexity via a one-pot operation. This minireview covers our recent advances on multicomponent reactions involving active methylene compounds for the construction of bioactive molecule skeletons. In many cases, MW-assisted MCRs offer considerable improvements in selectivity, chemical yield and purity and constitutes a very simple and extremely rapid method to access a diverse range of heterocyclic motifs

3-(4-Chloro­phen­yl)-1-(4-nitro­phen­yl)benzo[f]quinoline

In the title compound, C25H15ClN2O2, the pyridine ring is inclined at angles of 6.89 (7), 4.24 (9) and 66.98 (4)° with respect to the naphthalene, chloro­phenyl and nitro­phenyl rings, respectively. The two substituent aromatic rings make a dihedral angle of 71.1 (1)° with one another. C—H⋯π and π–π stacking are present in the crystal structure; the π–π stacking [centroid–centroid distance between the pyridyl rings of adjacent mol­ecules= 3.7838 (11) Å] links the mol­ecules into dimers, while the C—H⋯Cg type π–ring inter­actons link the mol­ecules into a chain structure along c

N-Cyclo­hexyl-3-(4-hydr­oxy-6-oxo-1,6-dihydro­pyrimidin-5-yl)-3-p-tolyl­propanamide

In the mol­ecule of the title compound, C20H25N3O3, the aromatic rings are oriented at a dihedral angle of 88.36 (3)°. The cyclo­hexane ring adopts a chair conformation. In the crystal structure, inter­molecular N—H⋯O and O—H⋯N hydrogen bonds link the mol­ecules. C—H⋯π inter­actions are also present