AIMS The recent increases in food prices caused by the corresponding increases in fertilizer costs have highlighted the demand for reducing the overuse of fertilizers in industrial agriculture. There has been increasing interest in developing plant root-targeted delivery (RTD) of fertilizers in order to address the problem of inefficient fertilizer use. The aim of this study is to develop a low...

background and objectives: the quefts model is using for optimizing fertilizer managements in crops, but it has not been used in iran yet. quefts accounts for interactions among npk affecting the ie of n, p and k and allows differentiation according to different yield levels targeted. it is necessary to determine crops parameters before application the model in the studying area. the first step...

background and purpose:organic dyes with a complex structure are often toxic, carcinogenic, mutagenic, non-biodegradation and stable in the environment and if released to the environment without treatment can endanger the environment and human health. the aim was to evaluate the performance nanoscalezero-valent iron (nzvi) in the removal of dye acid red 18 (ar18) from aqueous solutions. materia...

liquid membrane processes have attracted many interests in recent years for removal of heavy metals such as cadmium from industrial wastewaters. in this study, a modified hybrid liquid membrane system is introduced. the setup is worked by applying the water-insoluble dioctyl phthalate as the organic solvent. n-octanol and tetra butyl ammonium bromide are added to the organic phase to increase t...

background & aims of the study: dyes are one of the widespread chemicals which may have many adverse effects on life cycle. thus, this study was conducted to survey the rb19 dye removal efficacy from aqueous solution, using the sio2 nanoparticles. materials and methods: this study was an experimental-lab study. the batch adsorption system were utilized to evaluated the rb19 dye removal efficien...

It was hypothesized that nutrient removal from waste­ water could be achieved by using methane oxidizing bacteria (melhan­ otrophs). Because methane is inexpensive. it can be used as an energy source to encourage bacterial growth to assimilate nitrogen and phos­ phorus and other trace elements. This initial feasibility study used syn­ thetic nutrient mixtures and secondary sewage effluent as fe...

background: natural organic matter is the cause of many problems associated with water treatment such as the presence of disinfection by-products (dbps) and membrane fouling during water filtration. in this study, the performance of the peroxi-electrocoagulation process (pep) was investigated for the removal of humic acids (has) from aqueous solutions. methods: pep was carried out for the remov...

In this study, experiments have been conducted to evaluate the organics and nutrients removal from synthetic wastewater by a laboratory scale moving bed biofilm process. For nutrients removal, moving bed biofilm process has been applied in series with anaerobic, anoxic and aerobic units in four separate reactors. Moving bed biofilm reactors were operated continuously at different loading rates ...

In aquatic environments, eutrophication causes algal blooms, oxygen depletion, increase in undesired vegetation, loss of plant beds, fish, coral reef and other species. Eventually, the water bodies become unavailable to utilize for agricultural, recreational, industrial and drinking purposes. Discharge of domestic sewage introducing high levels of nutrients to water bodies is one of the main ca...

The interaction between the ions and the charge of membranes can affect the efficiency of pollutant removal. The present study investigated the removal efficiency of hexavalent chromium and nitrate ions from both actual and synthetic contaminated water via two different commercial spiral wound polyamide nanofilters. In addition, the interaction of ions under different experimental conditions wa...