نتایج جستجو برای: suspended sediment in karaj river was estimated first

تعداد نتایج: 17192350  

Journal: :The Science of the total environment 2001
P N Owens D E Walling J Carton A A Meharg J Wright G J Leeks

Samples of suspended, floodplain and channel bed sediment have been used to examine downstream changes in ediment-associated contaminant transport and storage in contrasting rivers in Yorkshire, UK. The concentrations of hosphorus, chromium and selected PCBs associated with sediment in the River Aire and its main tributary, the River Calder, which drain an urbanized and industrialized catchment...

Fatemeh Shokrian, K. Shahedi,

Estimate of sediment load is required in a wide spectrum of water resources engineering problems. The nonlinear nature of suspended sediment load series necessitates the utilization of nonlinear methods to simulate the suspended sediment load. In this study Artificial Neural Networks (ANNs) are employed to estimate daily suspended sediment load. Two different ANN algorithms, Multi Layer Perce...

Journal: :Water research 2002
Philip N Owens Desmond E Walling

The phosphorus content of fluvial sediment (suspended sediment and the < 63 microm fraction of floodplain and channel bed sediment) has been examined in contrasting rural (moorland and agricultural) and industrialized catchments in Yorkshire, UK. The River Swale drains a rural catchment with no major urban and industrial areas, and the total phosphorus (TP) content of fluvial sediment is genera...

, ,

Estimation of sediment loads in rivers is one of the most important, difficult components of sediment transport studies and river engineering. Accessing new methods that can be effective in this background are more important. In this research, we have used the artificial neural network (ANN) to optimize the results of the sediment rating curve (SRC) to predict the suspended sediment loads. For ...

2004
Peter T. Harris Michael G. Hughes Elaine K. Baker Robert W. Dalrymple Jock B. Keene

Current metre deployments, suspended sediment measurements and surface sediment samples were collected from three locations within distributary channels of the tidally dominated Fly River delta in southern Papua New Guinea. Net bedload transport vectors and the occurrence of elongate tidal bars indicate that mutually evasive ebband flooddominant transport zones occur in each of the distributary...

2008
Houjie Wang Zuosheng Yang Yan Wang Yoshiki Saito J. Paul Liu

r a 200 .005 dress: Ke , China. ail.ouc.e Summary The Changjiang (Yangtze River) has been effectively gauged since the 1950s and demonstrates the transformation of a river system due to intensified human activities in its drainage basin over the past 50 yr. However, the 50-yr measurements of water and sediment are inadequate to show the long-term trend of sediment flux from the river to the sea...

ژورنال: علوم آب و خاک 2000
استاد عسگری, منصور , شفاعی بجستان, محمود ,

The application of “Modified Einstein Procedure” is recommended by the Specialized Committee on Sediment, Iranian Ministry of Energy. However, this method has not been applied to any river in the country. It is the purpose of this study to investigate the total sediment load of the Karun and Karkheh rivers at Ahwas and Hamidieh stations. The graphical calculations of the method are very complic...

Journal: :محیط زیست طبیعی 0
سادات فیض نیا استاد دانشکده منابع طبیعی، دانشگاه تهران، ایران گلاله غفاری کارشناس ارشد آبخیزداری و عضو گروه پژوهشی مرکز خدمات تخصصی آب و خاک و gis معاونت پژوهش جهاد دانشگاهی واحد کردستان، ایران کیوان کریمی زاده کارشناس ارشد آبخیزداری و عضو گروه پژوهشی مرکز خدمات تخصصی آب و خاک و gis معاونت پژوهش جهاد دانشگاهی واحد کردستان، ایران منیرالسادات طباطبایی زاده دانشجوی کارشناسی ارشد مدیریت مناطق بیابانی، دانشکده منابع طبیعی، دانشگاه تهران، ایران

there is a lack of accurate and correct information about erosion in iran. moreover, there is a big difference between measurements and estimations. sediment is also an important environmental problem which pollutes water physically and chemically and therefore, sediment problem is usually studied as environmental problems. estimation of sediment yield of drainage basins is important for preven...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شهید چمران اهواز - دانشکده علوم 1370

1- in a search directed to the reaction of compound)23(the cycloaddition reaction of 1,3- diphenylisobenzofurane)14(with p-benzoquinone)19(,followed by addition of cyclopentadiene was carried out.the specific spacial stracture of its ir,nmr,mass spectra. 2- in another attempt the kinetic stability and behavior of compounds)20(and)23(was studied.the main subject of this study was the highly reve...

Journal: :Environmental science & technology 2008
Chaopeng Shen Mantha S Phanikumar Theng T Fong Irfan Aslam Shawn P McElmurry Stephanie L Molloy Joan B Rose

Viruses are important pathogens in both marine and fresh water environments. There is a strong interest in using bacteriophages as tracers because of their role as model viruses, since dissolved chemical tracers may not adequately describe the behavior of viruses that are suspended colloids. Despite a large number of studies that examined the transport of bacteriophages in the subsurface enviro...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید