the synthesis of functionalized 2-oxo-2h-coumarin derivatives has been studied by a one-pot reaction of o-hydroxybenzaldehyde, ethyl 2-bromoacetate and triphenylphosphine in the presence of catalytic amount of triethyl amine in etoac, water or under solvent free conditions. we have found the best results obtained under solvent free condition.

abstract in order to investigate the effects of nutrient resources and weed management on qualitative and quantitative criteria of cat tyme (teucrium polium), an experiment was conducted as split plot based on a complete randomized block design with 3 replications at the agricultural research station, ferdowsi university of mashhad, iran, during the years 2008 and 2009. treatments included diff...

In this paper, we present two different techniques to accelerate and approximate particle-based fluid simulations. The first technique identifies and employs larger time steps than dictated by the CFL condition. The second introduces the concept of approximation in the context of particle advection. For that, the fluid is segregated into active and inactive particles, and a significant amount o...

When one solves PDEs modelling physical phenomena, it is of great importance to take physical constraints into account. More precisely, numerical schemes have to be designed such that discrete solutions satisfy the same constraints as exact solutions. For instance, the underlying physical assumptions for the Euler equations are the positivity of both density and pressure variables. We consider ...