Electrospun nanofber membranes (ENMs) are new generation of membranes with many favorable properties such as high flux and low pressure drop. Although electrospinning has been known for more than a century, its applications in fltration and separation processes are relatively new. Electrospinning has provided the means to produce ultrathin fbers – as thin as a few nanome...

chipped stones, like many other archaeological artifacts, change in their original context. one of the most important changes is breakage. although it is clear that chipped stones which are gathered by archaeologists might have been broken, there have been few discussions made on the estimating the original number of chipped stones before breaking. in this article we have introduced different m...

All-dielectric frequency selective surfaces (FSSs) can serve as an alternative to their metallic counterparts when they must operate at very high power, loss must be minimized, or when the surface itself must be low observable. When metals are avoided, there is a weaker interaction with electromagnetic waves and it becomes more difficult to achieve strong suppression in the stop band while also...

The Grundy number of a graph G is the largest number of colors used by any execution of the greedy algorithm to color G. The problem of determining the Grundy number of G is polynomial if G is a P 4-free graph and N P-hard if G is a P 5-free graph. In this article, we define a new class of graphs, the fat-extended P 4-laden graphs, and we show a polynomial time algorithm to determine the Grundy...

fabrication of ultrafine grained materials by imposing severe plastic deformation for improvement of mechanical and physical properties of metals has been the focus of many researches over the past few years. in this process, a sheet is subjected to repetitive shear deformation conditions by utilizing asymmetrically grooved and flat dies through alternate pressing. in this study, a 2mm thick co...