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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

The role of microstructural and fluid processes in the genesis of gold-bearing shear zones : Fazenda Maria Preta mine, Rio Itapicuru greenstone belt, Bahia, Brazil

Xavier, Roberto Perez January 1991 (has links)
No description available.
132

Gold exploration in tropically weathered terrains : the formation, evolution and geochemistry of lateritic profiles in Liberia and Guinea, West Africa

Evans, Jon Michael January 2001 (has links)
No description available.
133

Applications of ultrasound in electrochemistry

Silva-Martinez, Susana January 1997 (has links)
No description available.
134

Fluid evolution related to gold mineralisation in the central Iberian zone

Murphy, Pamela Jane January 1994 (has links)
No description available.
135

Electrostatic self assembly of multilayer films incorporating metallic nanoparticles

Cant, Nicola Elizabeth January 2003 (has links)
No description available.
136

The geology exploration and evaluation of the gold deposits of Suriname

Smith, I. H. January 1987 (has links)
No description available.
137

The clinical value of monitoring gold levels in patients with rheumatoid arthritis undergoing chrysotherapy

Heath, M. J. January 1988 (has links)
No description available.
138

Gold and its financial derivatives

Cross, J. January 1994 (has links)
No description available.
139

Solution studies on the mucoadhesive potential of various polymers for use in gastrointestinal drug delivery systems

Fiebrig, Immo January 1995 (has links)
No description available.
140

Synthesis and characterization of gold (I) complexes of bis(diphenylphosphino)-acetonitrile.

Sithole, Sicelo Vincent. January 2010 (has links)
This study comprised the synthesis and characterization of select phosphine ligands and their complexation to gold(I). An initial approach was the reaction between Ph2PCl in "wet" organic solvent and [ClAu(tht)] (tht = tetrahydrothiophene) which led to the complex [ClAu{Ph2P(OH)}], 1, which was the second polymorph of this complex based on solid state Xray crystallographic studies. Related to the Ph2PCl precursor, the study refocused on the preparation of the ligand bis(diphenylphosphino)acetonitrile, (PPh2)2CHCN, ("dppm-CN"), 2, obtained from a modified literature method. Ligand 2 underwent a facile reaction with either [ClAu(tht)] or [(C6F5)Au(tht)] (molar ratio 1:2) to yield new open-ended dinuclear gold(I) complexes [(ClAu)2(dppm-CN)], 3, and [(C6F5Au)2(dppm-CN)], 4, respectively, both in satisfactory yield. Ligand 2 can also be deprotonated to form the anion [(PPh2)2CCN]¯ which reacted with [AuCl(tht)] (molar ratio 1:1) to form the neutral cyclic dinuclear gold(I) complex [Au2{(PPh2)2CCN}2], 5. The anion [(PPh2)2CCN··· showed unexpected reactivity behaviour toward mono- or bis(phosphine) gold(I) chloride complexes that led to the cleavage and formation of new Au-P bonds. Complexes 1, 3, 4, 5 were all subjected to a single crystal X-ray studies. Complex 1 has a central intermolecular Au···Au interaction of 3.0375(2) Å, and peripheral hydrogen bonding (O-H···Cl) within the structure. Complex 3 displays an intramolecular Au···Au interaction of 3.1669(4) Å, but no other intermolecular interactions. The structure of complex 4 reveals a side-by-side "dimer of dimers" structural motif in the solid state and represents a new type of system. Complex 4 contains intramolecular Au· · ·Au interactions alternating between 3.0902(7) Å and 3.0809(6) Å, and an intermolecular Au· · ·Au interaction of 3.592 Å. The next dimeric unit along the virtual 1D chain is more than 6 Å away. Complex 5 has an intramolecular Au···Au separation of 2.8650(4) Å and no intermolecular interactions. The C≡N bond in 5 is 1.160(7)° and is longer relative to the C≡N bond in complexes 3 and 4. The new complexes were further investigated by elemental analyses, mass spectrometry, 1H and 31P solution NMR, and FT-IR. The luminescence properties of the complexes was investigated in the solid state. Results showed 3 to be non- or very weakly emissive at room-temperature, the emission of 4 seems to be quenched by the C6F5 group at room temperature and qualitative results for 5 showed luminescence both at room temperature and at 77K. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2010.

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