background: natural radioactivity in materials under certain conditions can reach the hazardous radiological levels. so, it becomes necessary to study the natural radioactivity in different materials to assess the dose for the population in order to know the health risks and to have a baseline for future changes in the environmental radioactivity due to human activities. materials and methods: ...

Due to their potentials in light-weight, flexible, and semitransparent devices, organic photovoltaics are of great significance the field renewable energy. However, narrow intrinsic absorption spectrum materials hinders full utilization solar To fabricate a highly efficient opaque cell, it is greatly necessary modify optical properties device improve light absorption. In addition, growing inter...

The development of new conjugated organic materials for dyes, sensors, imaging, and flexible light emitting diodes, field-effect transistors, and photovoltaics has largely relied upon assembling π-conjugated molecules and polymers from a limited number of building blocks. The use of the dithiolodithiole heterocycle as a conjugated building block for organic materials is described. The resulting...

abstract coontail (ceratophyllum demersum) and watermilfoil (myriophyllum spicatum) are current submersed weeds in many fresh waters of iran. the excessive growth of these plants causes the reduction in utilization of water resources and making some ecological and economical damages in these areas. the aim of this study was to determine the response of two submerged aquatic weeds of coontail an...