The elemental stoichiometry of sea water and particulate organic matter is remarkably similar. This observation led Redfield to hypothesize that the oceanic ratio of nitrate to phosphate is controlled by the remineralization of phytoplankton biomass1. The Redfield ratio is used universally to quantitatively link the marine nitrogen and phosphorus cycles in numerous biogeochemical applications2–...

Phosphorus has been identified as an important determinant of nutrition-related biological variation. The macronutrients protein (P) and carbohydrates (C), both alone and interactively, are known to affect animal performance. No study, however, has investigated the importance of phosphorus relative to dietary protein or carbohydrates, or the interactive effects of phosphorus with these macronut...

abstract the objectives of this research was to evaluate the rhizospheric effects of wheat (triticum aestivum l.) on the status of various inorganic p fractions and total organic p in 10 calcareous soils amended with 1% (w/w) municipal sewage sludge from the refinery of shahrekord city under rhizobox conditions. thus, wheat plant was planted in completely randomized design with three replicatio...

We studied the role of phosphorus retention in parathyroid cell proliferation and parathyroid hormone (PTH) oversecretion in severe secondary parathyroid hyperplasia. Mice transplanted with human parathyroid tissue from a patient who had undergone parathyroidectomy for severe secondary hyperparathyroidism were divided into four groups; each group was given a diet with a different phosphorus con...

The Salton Sea is the largest inland water body in California, covering an area of 980 km(2). Inflow to the Salton Sea (1.6 km(3) yr(-1)) is predominately nutrient-rich agricultural wastewater, which has led to eutrophication. Because internal phosphorus release from the bottom sediments is comparatively low and external phosphorus loading to the Salton Sea is high, reduction of tributary phosp...

To understand the origin of cleavage fracture which dominates in Fe Mn -Al-C alloys at a high phosphorus concentration, we performed first-principles study of the phosphorus effect on ideal cleavage energy and critical stress in -carbide, Fe3AlC, a precipitate in the austenitic alloys. We find that phosphorus has higher solubility in Fe3AlC than in -Fe and sharply reduces the cleavage character...

The growth of the freshwater microalga Scenedesmus obliquus was studied at 30°C in a mineral culture medium with phosphorus concentrations of between 0 and 372 pro. The values for the specific growth rates, between So=0 #m and S,=298 pro, fitted a semistructured substrate-limitation model with #,,~ = 0.0466 h P.,,2 = 0.0256 h ~ and Ks = 0.2 ttm. The specific uptake rate of phosphorus reached a ...

Investigations were focused on the development of a technology for phosphorus (P) recovery straight from wastewater. Facing the finiteness of the natural resources of this essential nutrient, the declared goal must be the sustainable use of available phosphorus sinks such as wastewater treatment plants (WWTP) for the generation of P rock substitutes. A feasible method for simultaneous eliminati...

Studies investigating the effect of increasing CO2 levels on the phosphorus cycle in natural waters are lacking although phosphorus often controls phytoplankton development in many aquatic systems. The aim of our study was to analyse effects of elevated CO2 levels on phosphorus pool sizes and uptake. The phosphorus dynamic was followed in a CO2-manipulation mesocosm experiment in the Storfjärde...

We report, for the first time, the synthesis of the high-quality p-type ZnO NWs using a simple chemical vapor deposition method, where phosphorus pentoxide has been used as the dopant source. Single-crystal phosphorus doped ZnO NWs have their growth axis along the 001 direction and form perfect vertical arrays on a-sapphire. P-type doping was confirmed by photoluminescence measurements at vario...