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The role of microstructural and fluid processes in the genesis of gold-bearing shear zones : Fazenda Maria Preta mine, Rio Itapicuru greenstone belt, Bahia, BrazilXavier, Roberto Perez January 1991 (has links)
No description available.
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Gold exploration in tropically weathered terrains : the formation, evolution and geochemistry of lateritic profiles in Liberia and Guinea, West AfricaEvans, Jon Michael January 2001 (has links)
No description available.
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Applications of ultrasound in electrochemistrySilva-Martinez, Susana January 1997 (has links)
No description available.
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Fluid evolution related to gold mineralisation in the central Iberian zoneMurphy, Pamela Jane January 1994 (has links)
No description available.
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Electrostatic self assembly of multilayer films incorporating metallic nanoparticlesCant, Nicola Elizabeth January 2003 (has links)
No description available.
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The geology exploration and evaluation of the gold deposits of SurinameSmith, I. H. January 1987 (has links)
No description available.
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The clinical value of monitoring gold levels in patients with rheumatoid arthritis undergoing chrysotherapyHeath, M. J. January 1988 (has links)
No description available.
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Gold and its financial derivativesCross, J. January 1994 (has links)
No description available.
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Solution studies on the mucoadhesive potential of various polymers for use in gastrointestinal drug delivery systemsFiebrig, Immo January 1995 (has links)
No description available.
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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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