heat and mass transfer, in this paper, is considered in one-row heat exchanger, that fins are hotter than air flow and water is added to fins. related governing equations are derived by analyzing a two-dimension model in a unique cell of a heat exchange. these equations are numerically solved by finite difference method. heat transfer and efficiency under partially wet surface are calculated by...

the groundwater resources of the urmia plain have been under intensive tension for the last recent years. this has caused the production and observation wells to become dry and in some local places well deepening to take place. in some other locations, the groundwater level is high and there is a danger of local water logging condition along with its associated drainage work. for the settlement...

Introduction: Studying the changes in surface water storage and exchanges with groundwater in the hydrological system of rivers is a prerequisite for water resources management in the basin. In this paper, Zayandehrood River has been studied and the historical series of flow has been used in six hydrographic stations located downstream the Zayandehrood Dam. Materials and Methods: Based on the ...

batiaghata upazila, khulna district in south-west coastal region of bangladesh is the mostly saline affected area, where agriculture activities are mainly dependent on rainfall. 23 water samples from surface water and shallow tube well (stw) were collected in the monsoon season and analyzed for physico-chemical properties to classify them according to salinity hazard. electrical conductivity (e...

introduction: given its low and sparse precipitation both in spatial and temporal scales, iran is nestled in an arid and semiarid part of the world. on the other hand, because of population growth, urbanization and the development of agriculture and industry sector is frequently encountered with increasing water demand. the increasing trend of water demand will widen the gap between water suppl...

a new sorbent composed of 3-aminopropyltriethoxy-silane-coated magnetic nanoparticles, functionalized with rhodium(iii) porphyrin complex was synthesized and characterized by elemental analysis, x-ray diffraction (xrd), transmission electron microscopy (tem), fourier transform infrared spectroscopy (ft-ir) and thermogravimetric analysis (tga). the effect of some co-existing anions present in aq...

the relative impacts of different types of land use on the surface water quality are yet to be ascertained and quantified. in this paper, the influence of different types of land use on surface water quality is investigated. rain events samples from different land use in the central plateau, iran, were analyzed for major ions. statistical analyses were employed to examine the statistical relati...

the world is facing severe challenges in meeting the rapidly growing demand for water resources. in addition,irrigation water which is the largest use of water in most developing countries and arid and semi arid regions, will likelyhave to be diverted increasingly to meet the needs of the households in urban areas and industry sectors whilst remaining aprime engine of agricultural growth. a lin...

concentrations of six heavy metals including cr, mn, ni, pb, v and zn were determined in topsoil (from 47 grid cells), surface water (4 streams) and groundwater (8 wells and 4 qanats) from an agriculturalarea located at south part of the iranian capital, near the tehran oil refinery. concentrations of the elementswere measured using flame and flameless atomic absorption spectrometry. based on t...