Sökning: "Ulf Grandin"

Hittade 2 avhandlingar innehållade orden Ulf Grandin.

  1. 1. Long-term studies of succession : Colonisation and seed banks

    Författare :Ulf Grandin; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ellenberg indicator values; genetic variation; long-term study; Lythrum salicaria; Moehringia trinervia; primary succession; seed bank; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Using data from long-term studies of the vegetation in two areas under primary succession, patterns of colonisation and the accumulated seed bank during plant succession were studied.At century-old small islands in Lake Hjälmaren, Sweden, the genetic structure of differently old populations of Moehringia trinervia and Lythrum salicaria was studied, using allozyme variation for M. LÄS MER

  2. 2. Tribology of Metal-Graphite Composites : A Study of Sliding Electrical Contact Surfaces

    Författare :Martina Grandin; Wiklund Urban; Staffan Jacobson; Ulf Jansson; Christian Holzapfel; Uppsala universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; tribology; tribofilm; surface analysis; wear; friction; electrical contacts; metal-graphite; contact resistance; cross-section; nanocomposite coating; copper; silver; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

    Sammanfattning : An environmentally sustainable production of electrical power is important for preserving the earth’s natural resources. In order to utilize this power as efficiently as possible, it is of great importance to minimize the losses, for example in sliding electrical contacts. LÄS MER