Nowadays, the increasing population and water demand in various sectors of agriculture, industry, drinking and sanitation has brought about tremendous pressure on groundwater resources. Changes in groundwater quality and salinity of the water resources are currently major threats to development, especially in the dry and too dry lands. The aim of this study is evaluation of the trend of changes...

the caspian sea contains great resources of oil and gas. the caspian sea is a 700- mile- long body of water in central asia, land located between azerbaijan, iran, kazakhstan, russia and turkmenistan. iran was challenges and opportunities in the caspian region. key question in this thesis includes three section that first question, opportunities of iran in the caspian region, second question ch...

in this thesis, a better reaction conditions for the synthesis of spirobarbiturates catalyzed by task-specific ionic liquid (2-hydroxy-n-(2-hydroxyethyl)-n,n-dimethylethanaminium formate), calcium hypochlorite ca(ocl)2 or n-bromosuccinimide (nbs) in the presence of water at room temperature by ultrasonic technique is provided. the design and synthesis of spirocycles is a challenging task becaus...

Drought is a phenomenon that threating water quality in addition to its shortage. In this paper we investigate the effect of drought on surface water quality of Kashkan watershed. For this purpose, during the collection of meteorological data and water quality data during 20 years (1987 to 2009) from Meteorology and Water Resources offices of Lorestan province, initially duration and severity o...

the application of e-learning systems - as one of the solutions to the issue of anywhere and anytime learning – is increasingly spreading in the area of education. content management - one of the most important parts of any e-learning system- is in the concern of tutors and teachers through which they can obtain means and paths to achieve the goals of the course and learning objectives. e-learn...