Sökning: "S Lake"

Visar resultat 1 - 5 av 60 avhandlingar innehållade orden S Lake.

  1. 1. Temporal and spatial variation in the community composition of lake bacterioplankton

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Eva S. Lindström; Uppsala universitet.; [1998]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; bacterioplankton; freshwaters; 16S rDNA; DGGE; community composition; Biologi; NATURAL SCIENCES Biology; NATURVETENSKAP Biologi; limnologi; Limnology;

    Sammanfattning : Bacterioplankton are among the smallest and most abundant organisms in lake ecosystems. Due to the lack of relevant methods, the taxonomic composition of bacterioplankton has been studied less thoroughly than that of larger organisms. LÄS MER

  2. 2. Terrestrial response to Dansgaard-Oeschger cycles and Heinrich events : the lacustrine record of Les Echets, south-eastern France

    Detta är en avhandling från Stockholm : Institutionen för naturgeografi och kvartärgeologi

    Författare :Daniel S. Veres; Stockholms universitet.; [2007]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lake sediments; palaeoclimate; organic matter; Dansgaard-Oeschger cycles; Heinrich events; MIS 3; Western Europe; NATURAL SCIENCES Earth sciences Exogenous earth sciences Quaternary geology; NATURVETENSKAP Geovetenskap Exogen geovetenskap Kvartärgeologi; Quarternary Geology; kvartärgeologi;

    Sammanfattning : Marine Isotope Stage (MIS) 3 was an interval characterized by large and abrupt temperature changes on a millennial time scale, the so-called Dansgaard-Oeschger (DO) cycles and Heinrich events. Evidence for this high-frequency climate variability has been identified in many marine and ice core records. LÄS MER

  3. 3. C2- and C3-symmetric ligands via ring-opening of aziridines

    Detta är en avhandling från Stockholm : Kemi

    Författare :Fredrik Lake; KTH.; [2002]
    Nyckelord :asymmetric catalysis; aziridine; benzaldehyde; diethylzinc; enantionselective; ligand; proazaphosphatrane; ring-opening; sulfonamide; symmetry; titanium; nicronium;

    Sammanfattning : This thesis deals with the design and synthesis of chiralenantiopure nitrogencontaining ligands and the use of theseligands in asymmetric catalysis. A modular synthetic approachto enantiopure nitrogen-containing ligands was developed. Thesynthetic method is based on the ring-opening of activatedchiral aziridines by nitrogen nucleophiles. LÄS MER

  4. 4. Towards the Improvement of Salt Extraction from Lake Katwe Raw Materials in Uganda

    Detta är en avhandling från Stockholm : KTH Royal Institute of Technology

    Författare :Hillary Kasedde; KTH.; [2015]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Lake Katwe; salt extraction; brine; evaporites; saltpan; characterization; evaporation - crystallization; solubility; Pitzer ’s ion - interaction model; PHREEQC software; dissolution kinetics; Avrami model.;

    Sammanfattning : Uganda is well endowed with economic quantities of mineral salts present in the interstitial brines and evaporite deposits of Lake Katwe, a closed (endorheic) saline lake located in the western branch of the great East African rift valley. Currently, rudimentally and artisanal methods continue to be used for salt extraction from the lake raw materials. LÄS MER

  5. 5. Varved lake sediments and diagenetic processes

    Detta är en avhandling från Umeå : Ekologi, miljö och geovetenskap

    Författare :Veronika Gälman; Umeå universitet.; [2009]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Varved annually laminated lake sediment; diagenesis; varve appearance; iron; sulfur; chemical speciation; iron cycling; carbon; nitrogen; stabile isotopes; δ13C; δ15N; NATURAL SCIENCES Earth sciences; NATURVETENSKAP Geovetenskap;

    Sammanfattning : Varved (annually laminated) sediments are of great interest for inference of past environmental conditions, as they provide dated records with high time resolution. After deposition, the sediment varves are affected by diagenesis; i.e., chemical, physical and biological changes that occur within the sediment. LÄS MER