We consider an optimal control problem involving the use of bacteria for pollution removal where the model assumes the bacteria switch instantaneously between active and dormant states, determined by threshold sensitivity to the local concentration v of a diffusing critical nutrient; compare [7], [3], [6] in which nutrient transport is convective. It is shown that the direct problem has a solut...

* Corresponding author ([email protected]) Abstract: Recirculation (closed) type hydroponics, despite its comparative eco-friendliness and cost-effectiveness, is less popular in greenhouse agriculture due to the need for close monitoring of nutrient availability within the fertigation cycle. As a practicable and low cost measure, the uptake volume based supplementation of plant nutrients at hi...

Solution culture experiments were carried out to study the kinetics at cotyledon stage (11-day-old) and the effect of different NO3/NH4 on NO3 and NH4 uptake at seedling stage (31-day-old) with two cultivars of sugar beet, including Tianyan7 and Tianyan8. NO3 uptake by sugar beet seedlings at cotyledon stage (11-day-old) reached equilibration after 2 hours of adaptation, and NH4 uptake reached ...

Previous investigations have confirmed the potential effectiveness of various metabolic stimulants and physiological salt solutions in supporting broiler embryogenesis. The current study investigated the effects of the same solutions on chick posthatch performance and tissue nutrient profiles. In the first of 2 trials, 200 μL each of a (i) 0.18 mM carbohydrate electrolyte nutrient (CEN) solutio...

The purpose of this study was to investigate the response of physicochemical properties of gerbera (Gerbera Jamesonii L.) to silica nanoparticles (Nanoparticle-SiO2) and calcium chelate (Ca-Chelate) in nutrient solutions. A factorial experiment based on completely randomized design with two factors was conducted in four replicates. The first factor the concentration of Nanoparticle-SiO2 in nutr...

The present study was based on the hypothesis that Boron (B) induces changes of other micronutrients in soil-plant systems. A preliminary study was carried out in sand culture growing radish (cv. French breakfast) as a test crop, under green house conditions. The experiment was laid out in a randomized complete block design and replicated three times. Boron was applied at the rate of 0, 0.25, 0...

abstract regarding to this issue that nitrogen is one of the main essential elements for plant that growth and efficiency of plant is related to it, and on the other hand most of the water and soil resources in iran are alkaline; in order to evaluation of the interactive effect of different concentrations of sodium bicarbonate and nitrogen form on snap bean in hydroponic system, this research w...