Sökning: "quaternary science"

Visar resultat 1 - 5 av 55 avhandlingar innehållade orden quaternary science.

  1. 1. The development and implementation of software for palaeoenvironmental and palaeoclimatological research : the Bugs Coleopteran Ecology Package (BugsCEP)

    Författare :Philip Buckland; Roger Engelmark; Geoffrey Lemdahl; Paul Sinclair; Umeå universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; Quaternary geology; environmental archaeology; quaternary science; Coleoptera; beetles; database; environmental reconstructions; climate reconstructions; software; Mutual Climatic Range; MCR; palaeoentomology; Kvartärgeologi; Archaeology; Arkeologi; Archaeology; arkeologi;

    Sammanfattning : This thesis documents the development and application of a unique database orientated software package, BugsCEP, for environmental and climatic reconstruction from fossil beetle (Coleoptera) assemblages. The software tools are described, and the incorporated statistical methods discussed and evaluated with respect to both published modern and fossil data, as well as the author’s own investigations. LÄS MER

  3. 2. Glass Ionomer Cements with Improved Bioactive and Antibacterial Properties

    Författare :Song Chen; Håkan Engqvist; Wei Xia; Jie Zhou; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; biomaterial; glass ionomer cement; bioactivity; hydroxyapatite; monetite; calcium silicate;

    Sammanfattning : Dental restorative cements are placed in a harsh oral environment where they are subjected to thermal shock, chemical degradation, and repeating masticatory force. The ideal restorative dental cements should have superior mechanical properties, chemical stability, aesthetic, good handling properties, biocompatibility, antibacterial properties, and preferably bioactivity. LÄS MER

  4. 3. Greenhouse gas emissions from cultivated peat soils in Sweden

    Författare :Örjan Berglund; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Greenhouse gas emissions and peat subsidence are major concerns both from an environmental perspective and for farmers with declining soil production capacity. Agricultural databases, digitised maps of quaternary deposits and 40K radiation have been used in a GIS analysis to estimate the distribution and land use of agricultural organic soils in Sweden. LÄS MER

  5. 4. Late Quaternary Biostratigraphy of Sediments of the Southeastern Baltic Sea

    Författare :Daiva Üsaityté; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; SE Baltic Sea; pollen analysis; Late Quaternary; numerical zonation; principal components analysis; Geovetenskap; Earth sciences; Geovetenskap; Quarternary Geology; kvartärgeologi;

    Sammanfattning : This thesis presents Late Quaternary biostratigraphy in the SE Baltic Sea, based on palynological data from fifteen sediment cores. An objective subdivision of the cores has been achieved by numerical zonation. Ordination has revealed a succession of pollen spectra that can be used for biostratigraphic correlation across the region. LÄS MER

  7. 5. Utanför gränserna : En vetenskapshistorisk biografi om Astrid Cleve von Euler

    Författare :Kristina Espmark; Christer Nordlund; Bo Sundin; Anders Lundgren; Umeå universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; History of science; biography; women scientists; diatoms; botany; geology; archaeology; popular science; boundary-work; Astrid Cleve; Hans von Euler-Chelpin; Sweden; History Of Sciences and Ideas; idé- och lärdomshistoria;

    Sammanfattning : This dissertation is a scientific biography of Astrid Cleve von Euler. She was Sweden’s first female Ph.D. graduate in the natural sciences (1898) and pursued a scientific career in spite of formal and cultural limitations. LÄS MER