introduction: a modern technique for elemental analysis of biological samples is laser induced breakdown spectroscopy (libs). this technique is based on emission of excited atoms, ions, and molecules in plasma produced by focusing a high power laser pulses on sample surface. because of several advantages of libs including little or no sample preparation; minimally invasive; fast analysis time a...

An approximation technique is considered for computing transmission and reflection coefficients for plane waves propagating through stratified slabs. The propagation of elastic pulse through a planar slab is derived from first principles using straightforward time-dependent method. The paper ends with calculations of enhancement factor for the elastic plane wave and it is shown that it depends ...

In this paper, we used the time-of-flight (TOF) of a charge packet, that injected by a voltage pulse to calculate the drift velocity and mobility of holes in organic semiconducting polymers. The technique consists in applying a voltage to the anode and calculating the time delay in the appearance of the injected carriers at the other contact. The method is a simple way to determine the charge t...

introduction in recent years due to problems associated with intensive agricultural systems, the role of legumes in the sustainability of cropping systems has been accelerated (draper, 2006). currently, one of the challenges of energy intensive agricultural systems is monoculture, which is associated with low biological diversity (carmine, 2007). iran has been considered as the area with low ag...