Sökning: "sulphide"

Visar resultat 1 - 5 av 153 avhandlingar innehållade ordet sulphide.

  1. 1. Sulphide mineral flotation : a new insight into oxidation mechanisms

    Författare :Alireza Javadi; Jan D. Miller; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mineralteknik; Mineral Processing;

    Sammanfattning : Formation of hydrogen peroxide (H2O2), an oxidizing agent stronger than oxygen, by sulphide minerals during grinding was investigated. It was found that pyrite (FeS2), chalcopyrite (CuFeS2), sphalerite ((Zn,Fe)S), and galena (PbS), which are the most abundant sulphide minerals on Earth, generated H2O2 in pulp liquid during wet grinding in the presence or devoid of dissolved oxygen in water and also when the freshly ground solids are placed in water immediately after dry grinding. LÄS MER

  2. 2. Origin of the Kleva Ni-Cu sulphide mineralisation in Småland, southeast Sweden

    Författare :Karolina Bjärnborg; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Palaeoproterozoic; Fennoscandia; geochronology; geochemistry; sulphide remobilisation; gabbro–diorite; mantle; arc; ore genesis; Ni-Cu sulphide deposit;

    Sammanfattning : The Kleva Ni-Cu sulphide deposit is situated within a gabbro-diorite intrusive complex in southeast Sweden. The basement north of the intrusive complex is dominated by 1.81–1.77 Ga granites of the Palaeoproterozoic Transscandinavian Igneous Belt (TIB). LÄS MER

  3. 3. Embankments founded on sulphide clay : - some aspects related to ground improvement by vertical drains

    Författare :Rasmus Müller; Stefan Larsson; Göran Sällfors; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; geotechnical engineering; embankments; vertical drains; sulphide clay; Earth sciences; Geovetenskap;

    Sammanfattning : In this thesis, some aspects concerning building embankments founded on sulphide clay are studied, with special reference to ground improvement by preloading in combination with prefabricated vertical drains (PVD’s). The main purpose of the research was to increase empirical knowledge of the mechanical behaviour of sulphide clays subjected to embankment loadings and of the interaction between vertical drains and sulphide clays. LÄS MER

  4. 4. Sulphide capacities of mulicomponent slags

    Författare :Mselly M. Nzotta; KTH; []
    Nyckelord :;

    Sammanfattning : In the present thesis, experimental measurements have beencarried out to determine the sulphide capacities of the binaryslags Al2O3-MnO, "FeO"-SiO2, "FeO"-CaO, "FeO"-MnO, ternary slags Al2O3-MgO-SiO2, Al2O3-MnO-SiO2, Al2O3-CaO-MgO, MgO-MnO-SiO2, Al2O3-MgO-MnO,"FeO"-Al2O3-SiO2, "FeO"-CaO-SiO2, "FeO"-MgO-SiO2, "FeO"-MnO-SiO2,quatenary slags Al2O3-CaO-MgO-MnO, Al2O3- CaO-MgO-SiO2,Al2O3-CaO-MnO-SiO2, CaO-MgO-MnO-SiO2, quinary slag Al2O3-CaO-MgO-MnO-SiO2, and the six component slag "FeO"-Al2O3-CaO-MgO-MnO-SiO2.The technique used was to bring the melt to equilibrium witha gas mixturecontaining Ar-CO-CO2-SO2. LÄS MER

  5. 5. Seagrasses in warming oceans : physiological and biogeochemical responses

    Författare :Rushingisha George; Mats Björk; Martin Gullström; Teresa Alcoverro Pedrola; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Global warming; greenhouse gas; warming oceans; temperate; tropical; coastal waters; Western Indian Ocean WIO ; tidal variability; seagrass; photosynthesis; respiration; photorespiration; biogeochemical processes; sulphide; methane; nitrous oxide; carbon dioxide; Plant Physiology; växtfysiologi;

    Sammanfattning : The exponential increase of atmospheric greenhouse gas concentrations over the past 50 years has caused a rise in the global average temperature by more than 1ºC above pre-industrial levels. Ninety-three percent of this heat energy has been absorbed and stored by the oceans, increasing their temperatures, particularly in surface waters. LÄS MER