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  • 1995-1999  (4)
  • 1945-1949
  • conservation  (2)
  • epoxy resin  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Biodiversity and conservation 8 (1999), S. 1519-1532 
    ISSN: 1572-9710
    Keywords: Botrychium ; Pteridophyte ; grassland ; conservation ; plant community
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two species of Botrychium are present in the Bitcherland grasslands, B. lunaria and B. matricariifolium, and both are protected in this territory. They occur in five different continental grassland communities, (i) a dune grassland (Diantho-Armerietum), (ii) a mesotrophic sandy grassland (Viscario-Avenetum), composed of three sub-units, therophitic ( V.A. airetosum), meso-eutrophic (V.A. saxifragetosum) and acidic (V.A. violetosum caninae), and (iii) an oligotrophic sandy grassland (Aveno-Genistetum). Both species of Botrychium appear in the three sub-units of Viscario-Avenetum, but only one in Diantho-Armerietum (B. matricariifolium) and in Aveno-Genistetum (B. lunaria). These Botrychium species are present in quite similar habitats in other lowland areas in Central Europe. The conservation of these threatened species, sensitive to plant competition, requires the maintenance or restoration of extensive agricultural management with late cutting and no fertilization.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Biodiversity and conservation 8 (1999), S. 1435-1445 
    ISSN: 1572-9710
    Keywords: clay ; conservation ; pasture ; phytosociology ; ruderal plant ; trampling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Carex hordeistichos is a peri-Mediterranean species, which is rare over all its distribution range. In Lorraine (France), where the field investigations were conducted, as in other Western European areas, it is present only in secondary habitats, constituted of heavily trampled wet pastures and vehicle tracks on clayed soils. All plant communities with Carex hordeistichos described from Western European areas can be linked to the Carici hordeistichi-Trifolietum fragiferi association, classified in the Agropyro-Rumicion wet pasture alliance. The conservation of this threatened ruderal plant requires the maintenance of a high disturbance level through grazing, trampling and soil packing.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1042-7147
    Keywords: epoxy resin ; homopolymerization ; thermal decomposition ; combustion ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Tetraglycidyl 4,4′-diaminodiphenylmethane (TGDDM) undergoes homopolymerization on heating. Intramolecular reactions which compete with crosslinking favor the formation of cyclic structures with increasing thermal and fire resistance of the resin, whereas physical mechanical properties tend to decrease.The mechanism of thermal decomposition of TGDDM is studied by thermogravimetry, differential scanning calorimetry and thermal volatilization analysis with characterization of volatiles evolved and residue left. Thermal degradation of poly-(TGDDM) starts at 260°C with elimination of water from secondary alcoholic groups which is a typical pathway for epoxy resin degradation. Resulting unsaturations weaken bonds in the β-position and provoke the first chain breaking at allyl-amine and allyl-either bonds. With increasing temperature, saturated alkyl-ether bonds and alkyl carbon-carbon bonds are broken first, followed by the most stable alkyl-aryl bonds at T〉365°C. The combustion performance of TGDDM is discussed on the basis of the thermal degradation behavior.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Polymers for Advanced Technologies 7 (1996), S. 823-830 
    ISSN: 1042-7147
    Keywords: epoxy resin ; phosphorylated hardener ; combusion ; fire retardancy ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: The kinetics of curing tetraglycidyl 4,4′-diaminodiphenyl methane (TGDDM) or of the mixture TGDDM/diglycidylether of bisphenol A (DGEBA) by bis(m-aminophenyl)methylphosphine oxide (BAMPO) was studied using differential scanning calorimetry. At low advancement of curing (〈50%), the low activation energy interaction between epoxy and amino groups seems to be controlled by diffusion, whereas above 50% the role of homopolymerization tends to increase and the process becomes chemically controlled.BAMPO shows a higher fire-retardant effectiveness in the mixture TGDDM/DGEBA than in TGDDM or DGEBA alone, for which the oxygen and nitrous oxide index tests suggest a condensed phase or a gas phase fire-retardant action depending on phosphorus content. An intumescent char is formed on the surface of burning fire-retarded specimens which tends, however, to be oxidized, thus reducing the fire-proofing effect at high BAMPO content.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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