We study light absorption by weakly rough metal surfaces with the roughness amplitude and correlation length smaller than skin depth in metal. develop a systematic perturbative approach for calculation of absorptance such systems find that roughness-related variations are determined an interplay between several system parameters which can result, particular, greater amplitudes. show that, small...

Semiconductor photocatalysis has been intensively studied in recent decades for a wide variety of application such as hydrogen production from water splitting and water and air treatment. The majority of photocatalysts are, however, wide band-gap semiconductors which are active only under UV irradiation. In order to effectively utilize visible solar radiation, this thesis investigates various t...

Shield metal arc welding on the high strength low alloy steels in pipelines to transport natural gas from Iran is of great importance. In this article the effects of annealing heat treatment on properties of multi pass welding in different situations (6-4:30 , 4:30-3 , 3-1:30 , 1:30-12) with 36 in outside diameter is evaluated by chemical,  metallography, tensile, toughness and hardness. Tensil...