saluk mount is selected for devonian biostratigraphy. this area located at southwest of bojnurd. in this study three sections are selected and two sections, chahar-borj and tabar sections with a thickness of 650 m, which consist mainly of calcareous sediments was studied in detailed but third section, qelli section, with a thickness of about 450m which consist mainly of sandstone and evaporates...

Introduction: Deficit of rainfall and consequently, water scarcity is one of the most important problems in arid and semi-arid areas. Water collecting structures have a positive effect on light textured lands due to deposition of clay and organic matter, as well as controlling the floods will enhance the vegetation (Abdollahi et al., 2015). Water Collection in order to store surface water runof...

in this thesis, we exploit a simple and suitable method for immobilization of copper(ii) complex of 4?-phenyl-terpyridine on activated multi-walled carbon nanotubes [amwcnts-o-cu(ii)-phtpy]. this nanostructure was characterized by various physico-chemical techniques. to ensure the efficiency and fidelity of copper species, the implementation of three-component strategies in click-chemistry all...

     Management of underground resources has a special priority in arid and semi-arid in Iran. Increasing underground resources is one of the useful ways for providing water requirements during the drought years. The main objective of this study was for mapping underground dam in the arid and semi-arid area in western Iran. The first and important stage of underground dam construction is recogn...

Digital soil mapping includes soils, spatial prediction and their properties based on the relationship with covariates. This study was designed for digital soil mapping using binary logistic regression and boosted regression tree in Zarand region of Kerman. A stratified sampling scheme was adopted for the 90,000 ha area based on which, 123 soil profiles were described. In both approaches, the o...

Dust phenomenon is the One of the most important hazards in the dry and semi-arid region. The occurrence of this phenomenon is accompanied by many physical and financial losses. In this research, was studied the characteristic of land use and geomorphology dust source in Khorasan Razavi Province. At first, 65 soil dust sources were identified for the time period (2005-2016) by using the dust en...

heteropoly acids (hpa) and their salts have advantages as catalysts which make them both economically and environmentally attractive, strong br?nsted acidity, exhibiting fast reversible multi-electron redox transformations under rather mild conditions, very high solubility in polar solvents, fairly high thermal stability in the solid states, and efficient oxidizing ability, so that they are imp...

the issue of curriculum and syllabus evaluation and revision has been in center of attention right from when curriculum came into attention of educational institutions. thus everywhere in the world in educational institutions curricula and syllabi are evaluated and revised based on the goals, the needs, existing content, etc.. in iran any curriculum is designed in a committee of specialists and...