نتایج جستجو برای: sediment concentration and distribution
تعداد نتایج: 16928187 فیلتر نتایج به سال:
Background and purpose: The Common Coot (Fulica atra) is an abundant aquatic bird in North of Iran and is anticipated to be a good indicator for metal pollution on north wetlands of Iran. The aim of this study was to determining metals concentration in water, sediment samples and two organs of Common coot (liver and kidney). Materials and methods: This study was tested on water, sediment and 3...
a reconnaissance study has been made on the distribution of 238u, 232th, 40k, 137cs andgeochemical features in soil and sediment samples at various locations on the coast of bushehr in the persiangulf. in this study a gamma-ray spectrometer based on a high purity germanium detector and a pc basedmca and x-ray fluorescence (xrf) method were used. estimation of the measured radionuclide contentha...
the mahabad river watershed has been exposed to severe erosion as a result of landuse change. the aim of this study is to quantify the amount of sediment yield and the relationship between land use change and slope. different sources such as geologic and topographic maps, satellite images, hydrometric as well as meteorological data were used to extract and gather the information needed for this...
Background and purpose: Polycyclic aromatic compounds (PAHs) are considered as priority organic compounds pollutants worldwide due to their high toxicity. Presence of oil wells has made petroleum hydrocarbon as one of the sources of pollution in the Caspian Sea. These are the pollutants of soil and water which are very dangerous and lethal for the aquatic ecosystem. The purpose of this study wa...
sediment flushing of reservoirs is an operational technique, whereby previously accumulated sediments in the reservoirs are hydraulically removed by accelerated flow when the bottom desiltingoutlets of the dam are opened. in this research, the process of sediment flushing is simulated by a three dimensional numerical model in which sediment and flow interaction are reflected in the reservoirs. ...
Aghdarband coal mine, located in NE of Iran, with annual coal and waste production capacity of about twenty million and six thousand tons, respectively, causes the increase of the concentration of some heavy metals in the soil and surrounded sediments. This paper deals with geochemical distribution and environmental effects of the heavy metals on the sediments around the mine, using geochemical...
this study attempted to explore if teaching english collocations through two different modes of awareness-raising and input flooding has any possible differential effect on immediate retention as well as retention in a delayed assessment. it also compared the possible differential effect of teaching english collocations implicitly and explicitly on actively using the items in writing. m...
Soil is very important for the production of crops and foodstuffs. One of the most important environmental crisesin the relationship with soil is the phenomenon of soil loss and therefore the soil conservation is very important. In conditions that, there is not the possibility of establishing vegetation, the use of soil conditioners can be useful in controlling soil loss. The present study wa...
For the study of field wind erosion and the design and evaluation of wind erosion control techniques, detailed observations of soil particle transport and vertical destribution of eroded soil particles are needed. The objectives of this study were: 1) To describe one device for soil transport particle measurement, i. e. the BSNE sediment catcher and 2) To assess vertical distribution of wind–er...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید