Two types of multilayer-film slides for measurement of urea nitrogen in blood are reported here: one for whole-blood samples, the other for plasma or serum. Urea nitrogen concentrations in plasma are determined almost immediately, without preparation of reagents or centrifugation of blood samples. Because the sample volume applied to the slide is not critical, reliable results are quickly obtai...

A laboratory-scale completely autotrophic nitrogen removal over nitrite (Canon) biofilm reactor was applied to remove nitrogen and organic carbon from swine digester liquor for 150 d. A stable nitrogen removal rate was reached after a three-week adaptation period. The nitrogen loading rate of influent were 0.20±0.04, 0.26±0.04, 0.26±0.07 kg N m(-3) d(-1) in period I, II and III, respectively. N...

Standard nutritional advice for irrigated sugarcane in South Africa and Swaziland is based on soil sample analysis and threshold values that have been determined experimentally over many years with surface-applied fertilisers. Fertilisers are normally applied in solid form during the early stages of crop development and watered in by the next irrigation cycle. The increasing popularity of subsu...

The INCA (Integrated Nitrogen CAtchment) model is a semi-distributed, dynamic nitrogen model which simulates nitrogen fluxes in catchments. Sources of nitrogen can be atmospheric deposition, the terrestrial environment or direct discharges. The model can simulate nitrogen processes in six land use classes. There are three components included; the hydrological model, the catchment nitrogen proce...

Using a variational approach, we have investigated the effects of the magnetic field, the impurity position, and the nitrogen and indium concentrations on impurity binding energy in a Ga1-xInxNyAs1-y/GaAs quantum well. Our calculations have revealed the dependence of impurity binding on the applied magnetic field, the impurity position, and the nitrogen and indium concentrations.

To study the effects of applied nitrogen levels and wild mustard densities on the growth of wheat and wild mustard, a field experiment was conducted at Re-search and Experimental Field of Islamic Azad University of Ahvaz-Iran. The effects of three nitrogen levels namely 90, 150 and 210 kg.ha-1 and four wild mustard densities such as 0, 5, 10 and 15 plants.m-2 were evaluated in split plot arrang...

Nitrogen is essential for both vegetative and generative stages of plant growth. Nitrogen efficiency is related to plant growth, production cost, and fertilizer residue. Azolla has the ability to increase nitrogen fixation from the atmosphere. Thus, Azolla cultivation in paddy field is one strategy for improving nitrogen fertilizer efficiency and increasing plant vegetative and generative growt...

Soil water, salinity and nitrogen content are three major factors affecting crop production in arid and semi-arid areas. This study was performed in two years of 2009 and 2010 in a semi-arid area in order to investigate the effects of irrigation water quantity (as main plot), quality (saline water, as sub-plot), nitrogen fertilizer (as sub-sub plot) and their interactions on growth and yiel...