Oligomeric and Polymeric Nitrogen-Phosphorus Compounds: New Aspects of Plant Nutrition

1969 ◽  
Vol 8 (8) ◽  
pp. 617-617 ◽  
Author(s):  
W. Waněk
2009 ◽  
Vol 89 (11) ◽  
pp. 1871-1878 ◽  
Author(s):  
Arnon Dag ◽  
Eric Ben-David ◽  
Zohar Kerem ◽  
Alon Ben-Gal ◽  
Ran Erel ◽  
...  

Author(s):  
F. A. J. Armstrong ◽  
Susan Tibbitts

A photochemical reactor, using a medium power mercury arc lamp for oxidation of organic matter in sea water, is described. The decomposition of some known compounds in distilled water and in sea water, using a 380 W lamp, was followed. First order kinetics with rate constants in the range 0·2–4·0 h−1 were observed. All the nitrogen compounds tested, including urea and some of its derivatives, were oxidized quantitatively. Breakdown of phosphorus compounds was rapid, but polyphosphate esters yielded polyphosphate ion which was only slowly hydrolysed to reactive orthophosphate. If polyphosphate is to be determined, hydrolysis by heating with acid should follow the irradiation. Some samples of English Channel water contained 0·02-0–05 fig-axom P/1. as organic polyphosphate.


1965 ◽  
Vol 45 (3) ◽  
pp. 219-225 ◽  
Author(s):  
W. T. Cram

Field applications to strawberry of nitrogen, phosphorus and potassium had no significant effect on the fecundity of the obscure root weevil, Sciopithes obscurus Horn, fed on detached leaflets in the laboratory, but when nitrogen was not applied there was a significant reduction in the fecundity of the black vine weevil, Brachyrhinus sulcatus (F.). With strawberry in sand culture, low levels of nitrogen had no apparent effect on the fecundity of S. obscurus but were associated with a significant reduction in the fecundity of B. sulcatus. Some association is suggested between the different effects of nitrogen nutrition on these species and their different susceptibilities to cyclodiene insecticides.


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