Mixed anhydrides of phosphorus sulfonic acids RR'P(O)OSOzR" 1 are of interest in the biological transfer of sulfates'. In the chemical synthesis of oligonucleotides, phosphoric sulfonic anhydrides 1 (R', R = nucleoside) are postulated as important and reactive intermediatesw-s-. Anhydrides 1 were also suggested as intermediates in biooxidation of thiolophosphates'. Structural analogues of anhyd...

Accurate information on the chemical nature of soil phosphorus is essential for understanding its bioavailability and fate in wetland ecosystems. Solution phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy was used to assess the conventional colorimetric procedure for phosphorus speciation in alkaline extracts of organic soils from the Florida Everglades. Molybdate colorimetry mark...

Large-area substitutional phosphorus-nitrogen co-doped monolayer graphene is directly synthesized on a Cu surface by chemical vapor deposition using molecules of phosphonitrilic chloride trimer as the phosphorus and nitrogen sources. The doping levels of both phosphorus and nitrogen atoms decrease as a function of the growth temperature. In contrast, the doping effect is enhanced with temperatu...

this study was carried out to determine effects of phosphorus residual applied to wheat on vetch (vicia panonioca) growth, yields and some  soil  physical, chemical  properties in soil. the experiment was conducted with randomized completely block design in a field with three replications including four levels of p residual (applied for wheat p0, p15, p30, and p45 kg p2o5 in hectare) from tripl...

in order to evaluation the effects of different soil fertility systems on chickpea seed quality, field experiments were carried out in sanandaj agriculture research station of iran in 2007 and 2008 growing seasons. experimental units were arranged in split-split plots based on randomized complete blocks with three replications. green manure levels considered main plots, base fertilizer compound...

Effluents from recirculating aquaculture systems (RAS) contain high concentrations of nitrogen and phosphorous wastes and thus often require proper treatment to prevent potential detrimental impacts on receiving water bodies. The purpose of this study was to evaluate the feasibility of membrane filtration coupled with chemical precipitation as a pretreatment step with emphasis on phosphorus rem...

Some treatment plants in operation have not been designed to fulfill the required standards of phosphorus removal. A possibility to upgrade the efficiency of phosphorus removal could be elimination of the phosphorus returned with sludge processing liquors by releasing and recovering from sewage sludge. The phosphorus recovery can occur from sewage sludge by chemical methods or from supernatant ...

In order to confine the aqua-eutrophication problem arising from phosphorus pollution, many municipal wastewater treatment plants have to improve their executive drainage standard for total phosphorus (TP). In this study, a municipal wastewater treatment plant employing modified Carrousel oxidation ditch as main biological treatment unit was selected as a representative case. Technical necessit...

The aims of this study were to evaluate the quantitative and qualitative chemical compound of the calcium and phosphorus ions on the carious radicular dentine surfaces resulted after lesional treatment with Carisolv system and to compare with the healthy radicular surfaces. EDX method was used for quantitative and qualitative chemical microanalysis of dentine radicular surfaces. This method als...