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Visar resultat 1 - 5 av 212 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Extraction of Metal Values : Thermodynamics of Electrolyte Solutions and Molten Salts Extraction Process

   Författare :Xinlei Ge; Seshadri Seetharaman; Katsunori Yamaguchi; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrolyte solutions; activity coefficient; osmotic coefficient; freezing point depression; boiling point elevation; Materials science; Teknisk materialvetenskap;

   Sammanfattning : Over the past centuries, a number of process routes for extraction of metal values from an ore or other resources have been developed. These can generally be classifiedinto pyrometallurgical, hydrometallurgical or electrometallurgical routes. LÄS MER

3. 2. Metal fate and sensitivity in the aquatic tropical vegetable Ipomoea aquatica

   Författare :Agneta Göthberg; Maria Greger; Hans Borg; M.N.V. Prasad; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aquatic plants; vegetables; methyl mercury; metal accumulation; metal effects; thiol-rich peptides; Ipomoea aquatica; Plant physiology; Växtfysiologi; Applied Environmental Science; tillämpad miljövetenskap;

   Sammanfattning : The aquatic plant Ipomoea aquatica is a popular vegetable in Southeast Asia, often cultivated in nutrient rich and polluted waters. The overall aim of this thesis was to estimate potential risks for human health and reduced plant growth due to accumulation and toxicity of total-Hg, methyl-Hg, Cd and Pb. LÄS MER

4. 3. Metal-Organic Complexes at Surfaces

   Författare :Cristina Isvoranu; Synkrotronljusfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; x-ray absorption spectroscopy; x-ray photoelectron spectroscopy; bi-isonicotinic acid; oxalic acid; spin change; gas adsorption; metal-organic complex; iron phthalocyanine; scanning tunneling spectroscopy; resonant photoemission spectroscopy;

   Sammanfattning : The adsorption of different metal-organic complexes at surfaces was investigated by spectroscopic techniques (x-ray photoemission spectroscopy, x-ray absorption spectroscopy, resonant photoemission spectroscopy) and by scanning tunnelling microscopy. The investigation methods are able to provide atomic scale information on the studied systems, which moreover originates from the top-most atomic layers in a sample, meaning that they are surface sensitive techniques. LÄS MER

5. 4. Compounds with Non-Buttressed Metal-Metal Bond between Platinum and Thallium. Model Systems for Photoinduced Two-Electron-Transfer

   Författare :Mikhail Maliarik; KTH; []
   Nyckelord :thallium; platinum; cyanide; metal-metal bond; non-buttressed; heterometallic; photoinduced; electron transfer; redox reaction; NMR; chemical shift; spin-spin coupling constant; Raman; EXAFS; X-ray diffraction; equilibrium; oxidation state; oxidative;

   Sammanfattning : A new family of oligonuclear cyano compounds incorporatingtransition (Pt) and main group (Tl) metals bound with anon-buttressed Pt-Tl bond was synthesised in aqueous solution.The metal-metal linkage is formed in the reaction betweenplatinum and thallium in their stable oxidation forms, Pt(II)and Tl(III), orvice versa: Pt(IV) and Tl(I). LÄS MER

7. 5. Metal Gate Technology for Advanced CMOS Devices

   Författare :Gustaf Sjöblom; Jörgen Olsson; Stefan de Gendt; Uppsala universitet; []
   Nyckelord :Electronics; metal gate; high-k dielectrics; titanium nitride; zirconium nitride; MOSFET; thin film; work function; XPS; Elektronik;

   Sammanfattning : The development and implementation of a metal gate technology (alloy, compound, or silicide) into metal-oxide-semiconductor field effect transistors (MOSFETs) is necessary to extend the life of planar CMOS devices and enable further downscaling. This thesis examines possible metal gate materials for improving the performance of the gate stack and discusses process integration as well as improved electrical and physical measurement methodologies, tested on capacitor structures and transistors. LÄS MER