Sökning: "Elemental composition analysis"

Visar resultat 1 - 5 av 57 avhandlingar innehållade orden Elemental composition analysis.

  1. 1. Investigation of lithium and fluorine content in geological materials using Nuclear Reaction Analysis (NRA)

    Författare :Nathaly de La Rosa; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nuclear reaction analysis NRA ; Geological material; Elemental composition analysis; Ion Beam Analysis IBA ;

    Sammanfattning : This work focuses on the optimization of the Nuclear Reaction Analysis (NRA) technique to determine the content of lithium and fluorine in geological materials. Measuring low concentration of these isotopes is of great relevance in many fields such as geological, astrophysical, biological and material sciences. LÄS MER

  3. 2. Studies of Tropospheric and Stratospheric Aerosol using Ion Beam Analysis

    Författare :Giorgos Papaspiropoulos; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmosphere; Aerosols; troposphere; stratosphere; ion beam analysis; PIXE; impactors; particulate sulphur; chemical speciation; elemental analysis; thermography; Physics; Nuclear physics; Fysik; Metrology; Kärnfysik; physical instrumentation; Metrologi; fysisk instrumentering; Fysicumarkivet A:2001:Papaspiropoulos;

    Sammanfattning : Atmospheric aerosol particles are believed to have an impact on the radiative forcing of the earth's surface. The predicted results indicate a net cooling effect on the global climate, however there are few studies available to substantiate this and experimental data are needed. LÄS MER

  4. 3. Fuel conversion and ash formation interactions : a thermochemical study on lignocellulosic biomass

    Författare :Anna Strandberg; Markus Broström; Rainer Backman; Christoffer Boman; Maria Zevenhoven; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Char conversion; pyrolysis; devolatilization; ash transformation; biomass; fuel characterization; fuel composition; ash composition; silicate formation; carbonate formation; thermogravimetric analysis; micro-tomography;

    Sammanfattning : Biomass is considered to be CO2 neutral, and to be able to reduce the dependency on fossil fuels the need for expanded and sustainable biomass feedstock is increasing. Ash-related problems are some of the most important aspects of this increasing use of new biomass assortments in thermal energy conversion systems. LÄS MER

  5. 4. Geochemistry of tin, tungsten and molybdenum in Swedish Proterozoic granitoids : its potential use in regional mineral exploration

    Författare :Karl-Magnus Drake; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Granitoid; lithogeochemistry; Sn; W; Mo; Li; geotectonic - chronologic subdivision; geochemical-statistical grouping; uni- and multivariate statistical analysis; computer programs; metallogenic element distributions; Sn-W-concentration patterns; ore-bearing potential; probability calculations; petrometallogenic element ratios; petrochemical trends; postmagmatic alterations; geochemical variability; normative composition; genesis; absolute age; bibliography; analysis databank; Proterozoic; Sweden; N5600 N6800 E2330 E1120;

    Sammanfattning : The primary aim of this broad regional study is to statistically determine the Li-Sn-W-Mo-bearing potential of various granitoids using geochemical criteria.Computer-based, univariate and multivariate statistical methods are applied to major and trace element data from ca 660 granitic rock samples and over 800 major element analyses, selected from the Swedish geological literature. LÄS MER

  7. 5. Synthesis of Transition Metal Aluminides from Elemental Powder Mixtures

    Författare :Hossein Sina; Materialteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aluminides; Intermetallics; Powder Metallurgy; Reactive Sintering; Combustion Synthesis; Thermal Analysis; DSC; Onset temperature; Phase evolution; SEM; EDS; XRD;

    Sammanfattning : Structural components such as those used in gas turbines for energy conversion applications, are subjected to high loads at elevated temperatures. In order to ensure that the components survive under these conditions for a sufficiently long time, it is imperative to select materials with good high temperature properties like strength and corrosion resistance. LÄS MER