Sökning: "Organic phosphorus"

Visar resultat 1 - 5 av 112 avhandlingar innehållade orden Organic phosphorus.

  1. 1. New methods and reagents for small scale synthesis of phosphor organic compounds with focus on the phosphonic acids and their analogues

    Författare :Rikard Wärme; Dan Johnels; Jacek Stawinski; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; micro scale; phosphorus oxyacids; solid phase; chlorination; fluorination; radiolabelling; Organic synthesis; Organisk syntes; organisk kemi; Organic Chemistry;

    Sammanfattning : The development of a synthetic method of radiolabelled methylphosphono-fluoridates on a milligram scale is presented. The aim of this method is, besides affording high yield, to choose reaction pathways and reagents so that handling and transfer of labelled toxic substances is minimised, thereby reducing the risk of exposure as much as possible. LÄS MER

  2. 2. Novel Approaches to Phosphorus-containing Heterocycles and Cumulenes

    Författare :Anna Arkhypchuk; Sascha Ott; John D. Protasiewicz; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; phosphorus; phosphole; oxaphosphole; cumulene; phospha-Wittig-Horner reagent; molecular electronics; Kemi; Chemistry;

    Sammanfattning : Fast development in all areas of life and science over the last 50 years demands versatile, energy efficient and cheap materials with specific but easily tuneable properties which can be used for example in organic light emitting diodes (OLEDs), thin-film transistors, photovoltaic cells, etc. This thesis is devoted to the development of novel synthetic approaches to molecules with potential applications in the field of molecular electronics. LÄS MER

  3. 3. Organic phosphorus speciation in environmental samples : Method development and applications

    Författare :Julia V. Paraskova; Per J.R. Sjöberg; Emil Rydin; William T. Cooper; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Organic phosphorus; DNA; phospholipids; inositol phosphates; sediment; soil; extraction; liquid chromatography LC ; mass spectrometry MS ; Kemi med inriktning mot analytisk kemi; Chemistry with specialization in Analytical Chemistry;

    Sammanfattning : This thesis investigates the development of new methodology for the identification and quantification of organic phosphorus compounds in environmental samples.Phosphorus is a vital element for primary production and one of the factors contributing to eutrophication. LÄS MER

  4. 4. Organic Phosphorus Compounds in Aquatic Sediments : Analysis, Abundance and Effects

    Författare :Joakim Ahlgren; Emil Rydin; Monica Waldebäck; Lars Tranvik; Karin Markides; Sven Blomqvist; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; Organic phosphorus; aquatic sediment; eutrophication; NMR; internal loading; sample preparation; extraction; degradation; Miljökemi; Environmental chemistry; Miljökemi;

    Sammanfattning : Phosphorus (P) is often the limiting nutrient in lacustrine and brackish eco-systems, and enhanced input of P into an aquatic system might therefore negatively impact the environment. Because modern waste water manage-ment have reduced external P input to surface waters, internal P loading from the sediment has become one of the main P sources to aquatic ecosys-tems, in which relatively unknown organic P compounds seem to be more active in P recycling than previously thought. LÄS MER

  5. 5. Organic Phosphorus Compounds in Aquatic Sediments : Towards Molecular Identification with Mass Spectrometry

    Författare :Heidi De Brabandere; Monica Waldebäck; Emil Rydin; Per J. R. Sjöberg; Rolf Danielsson; William T. Cooper; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; electrospray ionisation; mass spectrometry; liquid chromatography; organic phosphorus; aquatic sediment; eutrophication; sample preparation; extraction; Analytical chemistry; Analytisk kemi;

    Sammanfattning : Phosphorus (P) regulates trophic status in most aquatic systems. However, only bioavailable P contributes to primary production. In most lakes and shallow seas, mineralisation of sediment P into its bioavailable form and its release to the water column is important for maintaining primary production. LÄS MER