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Visar resultat 1 - 5 av 229 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Quaternary paleoceanography of the Arctic Ocean : A study of sediment stratigraphy and physical properties

   Författare :Emma Sellén; Martin Jakobsson; Jan Backman; Dorthe Klitgaard-Kristensen; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Arctic Ocean; sedimentology; Quaternary; stratigraphy; physical properties; Earth sciences; Geovetenskap; Quaternary geology; Kvartärgeologi; Sedimentology; Sedimentologi; Marine Geoscience; marin geovetenskap;

   Sammanfattning : A Quaternary perspective on the paleoceanographic evolution of the central Arctic Ocean has been obtained in this PhD thesis by studying sediment cores from all of the Arctic’s major submarine ridges and plateaus. The included cores were mainly recovered during the Healy-Oden Trans-Arctic expedition in 2005 and the Lomonosov Ridge off Greenland expedition in 2007. LÄS MER

3. 2. Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean

   Författare :Daniela Hanslik; Martin Jakobsson; Marit-Solveig Seidenkrantz; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic Ocean; Quaternary; biostratigraphy; foraminifera; paleoceanography; Other earth sciences; Övrig geovetenskap; Marine Geoscience; marin geovetenskap;

   Sammanfattning : The central Arctic Ocean is one of the least explored deep sea regions and long biostratigraphic sediment records are sparse. The main focus of this thesis is the Arctic Ocean foraminiferal record and its application to reconstruct paleoceanographic variations and summer sea ice cover changes between late Quaternary interglacial periods. LÄS MER

4. 3. Cellulose in quaternary ammonium hydroxide solutions

   Författare :Shirin Naserifar; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; quaternary ammonium hydroxides; cellulose; N; N-dimethylmorpholinium hydroxide; Triton B; NaOH; dissolution; TMAH; etherification;

   Sammanfattning : An ever-increasing demand to shift away from fossil-based feedstock towards renewable resources has led to more use of bio-based materials. Cellulose being the most abundant biopolymer on Earth has received a considerable attention with a wide range of applications (in textile fibers, films, membranes, etc. LÄS MER

5. 4. The influence of stress on clay microstructure : an investigation of pre-Quaternary and Quaternary clay sediments

   Författare :Roland Pusch; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : .... LÄS MER

7. 5. Late Quaternary ice sheet history and dynamics in central and southern Scandinavia

   Författare :Timothy Johnsen; Helena Alexanderson; James T. Teller; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Scandinavian ice sheet; ice sheet dynamics; luminescence dating; cosmogenic exposure dating; geochronology; moraine; interstadial; deglaciation; nunatak; Quaternary geology; Kvartärgeologi; kvartärgeologi; Quarternary Geology;

   Sammanfattning : Recent work suggests an emerging new paradigm for the Scandinavian ice sheet (SIS); one of a dynamically fluctuating ice sheet. This doctoral research project explicitly examines the history and dynamics of the SIS at four sites within Sweden and Norway, and provides results covering different time periods of glacial history. LÄS MER