‎a ring $r$ is strongly clean provided that every element‎ ‎in $r$ is the sum of an idempotent and a unit that commutate‎. ‎let‎ ‎$t_n(r,sigma)$ be the skew triangular matrix ring over a local‎ ‎ring $r$ where $sigma$ is an endomorphism of $r$‎. ‎we show that‎ ‎$t_2(r,sigma)$ is strongly clean if and only if for any $ain‎ ‎1+j(r)‎, ‎bin j(r)$‎, ‎$l_a-r_{sigma(b)}‎: ‎rto r$ is surjective‎. ‎furt...

clean hydrogen is the major energy carrier for power production. the conversion of co to co2 and zero emission during hydrogen energy production causes high capital cost. it is a matter of prestige to optimize the process in order to make zero emission and cost effective production of clean hydrogen energy and electric power. in this era, coal gasification is the most promising technology for t...