high temperatures are often encountered in almost all of the combustion systems, therefore, thermal radiation heat transfer can influence the droplets heat up rate and consequently their life time. in this paper, the effect of thermal radiation heat transfer is investigated for two cases of directional and spherically symmetric illuminations. the flow and temperature fields insdie and outside o...

The synthesis of a series of C1-symmetric metallocene complexes rac-[1-(5,6-dialkoxy-2-methyl1-η5-indenyl)-2-(9-η5-fluorenyl)ethane]zirconium dichlorides (alkyl: n-butyl, n-hexyl, n-octyl, ndecyl) is described. These complexes are versatile catalysts in the polymerization of propylene after in situ activation with triisobutylaluminum (TIBA) and Ph3C[B(C6F5)4] in toluene and heptane solution. Al...

in this paper‎, ‎we determine the simple groups $g=ab$‎, ‎where $b$ is isomorphic to $l_{3}(4)$ and $a$ isomorphic to an alternating or a symmetric group on $ngeq5$‎, ‎letters‎.

in this paper‎, ‎we determine the simple groups $g=ab$‎, ‎where $b$ is isomorphic to $l_{3}(4)$ and $a$ isomorphic to an alternating or a symmetric group on $ngeq5$‎, ‎letters‎.

‎The symmetric doubly stochastic inverse eigenvalue problem (hereafter SDIEP) is to determine the necessary and sufficient conditions for an $n$-tuple $sigma=(1,lambda_{2},lambda_{3},ldots,lambda_{n})in mathbb{R}^{n}$ with $|lambda_{i}|leq 1,~i=1,2,ldots,n$‎, ‎to be the spectrum of an $ntimes n$ symmetric doubly stochastic matrix $A$‎. ‎If there exists an $ntimes n$ symmetric doubly stochastic ...

The promoting effect of niobium in a Li/MgO catalyst for the oxidative coupling of methane (OCM) and for the oxidattve dehydrogenation of ethane (ODHE) has been studied in some detail. it has been found that a Li/Nb/MgO catalyst with 16 wt % niobium showed the highest activity for the C, production in the OCM reaction; the activity at 600 “C was ten times that of the Li/MgO catalyst at the same...

Commutative properties of four-dimensional generalized symmetric pseudo-Riemannian manifolds were considered. Specially, in this paper, we studied Skew-Tsankov and Jacobi-Tsankov conditions in 4-dimensional pseudo-Riemannian generalized symmetric manifolds.

In this paper we introduce a special form of symmetric matrices that is called central symmetric $X$-form matrix and study some properties, the inverse eigenvalue problem and inverse singular value problem for these matrices.

In the present work, the transformation of m-xylene was studied over fresh and pre-coked HZSM-5 catalyst in a riser simulator over the temperature range of 350-500C.Significant differences were observed in both the activity and product selectivity pattern for the two forms of the catalyst. While, the fresh catalyst generally gave higher m-xylene conversion, the pre-coked catalyst produced highe...