Palladium-Catalyzed Synthesis of Substituted Hydantoins—A New Carbonylation Reaction for the Synthesis of Amino Acid Derivatives

One-step synthesis of substituted hydantoins can be achieved by the palladium-catalyzed “ureidocarbonylation” of aldehydes with urea derivatives and carbon monoxide [Eq. (1)]. This surprisingly selective protocol converts substituted ureas into 1,5- and 1,3,5-substituted hydantoins in yields of up to 93 %.     

Design,synthesis, in vivo and in vitro studies of 1,2,3,4-tetrahydro-9H-carbazole derivatives,highly selective and potent butyrylcholinesterase inhibitors

Molecular Diversity - Inhibition of butyrylcholinesterase (BChE) might be a useful therapeutic target for Alzheimer’s disease (AD). A new series of 1,2,3,4-tetrahydro-9H-carbazole derivatives...     

Exact Solutions of Dirac Equation and Particle Creation in (1+3)-Dimensional Robertson-Walker Spacetime

The exact solutions of the Dirac equation are discussed for a Robertson-Walker spacetime with asymptotically Minkowskian in and out regions. We obtain the mode solutions which reduce to positive and negative Minkowskian spinors in asymptotically regions. Using the obtained solutions we compute the density of created particles.     

A modified volume of fluid advection method for uniform Cartesian grids

This paper presents a modification on the stair-shaped volume of fluid (VOF) advection algorithm called defined donating and accepting region (DDAR) scheme which shows the importance of the more accurate definition of donating and accepting region. The algorithm which is suitable for uniform Cartesian grids uses multi-dimensional method of cell boundary flux integration. The performance of the modified scheme presented here has been compared with the performance of a number of alternative schemes taking into account translation, rotation and shear advection tests. In some aspects, the DDAR scheme is shown to be more accurate than linear constant and flux limited schemes, and in some way comparable with the linear piecewise schemes (PLIC). Without using any geometrical information, DDAR scheme predicts flux correctly using information of cell volume fraction and its face velocities and consequently improves the performance the first order DDR schemes.     

t-clique ideal and t-independence ideal of a graph

In this paper, we introduce and study families of squarefree monomial ideals called clique ideals and independence ideals that can be associated to a finite graph. A family of clique ideals with linear resolutions has been characterized. Moreover, some families of graphs for which the quotient ring of their clique ideal is Cohen–Macaulay are introduced and some homological invariants of the clique ideal of a graph G, which is the complement of a path graph or a cycle graph, are obtained. Also some algebraic properties of the independence ideal of path graphs, cycle graphs and chordal graphs are studied.     

Transverse magnetic wave propagation along flat biological membranes

Propagation of the transverse magnetic waves along flat biological membranes are studied within the framework of the classical electrodynamics. The ionic excitations adjacent to the exterior and interior surfaces of the flat cell membranes are modeled by a quasi two-dimensional (2D) layers of counter-ions fluid which is described by means of the linearized hydrodynamic theory. Dispersion relation of the plasma wave in the system is obtained by solving Maxwell and fluid equations with appropriate boundary conditions.     

Prediction of vapor-liquid equilibrium data of the system MTBE + methanol + ethanol by PRSV2 EOS

The Stryjek and Vera (1986) [9] modification of Peng-Robinson (PRSV2) equation of state has been applied for modeling vapor-liquid equilibrium of the systems MTBE + methanol, MTBE + ethanol and methanol + ethanol. Binary interaction parameters for mixing rules have been estimated by using experimental data at the atmospheric pressure. The calculated binary interaction parameters were used for predicting azeotropic behavior at high pressure and also for isobaric equilibrium points which showed an excellent agreement with experimental data. In addition, estimated binary interaction parameters for binary systems were used for ternary system (MTBE + methanol + ethanol). The predictions deviated only slightly from the experimental data. The results show PRSV2 can be used for VLE prediction of polar systems.