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Showing 1 to 20 of 34 for “"polymetallic"”.
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Transport phenomena at elevated temperatures - studies related to direct polymetallic smelting
… of two key areas of transport phenomena in a new polymetallic smelter has been achieved by using both mathematical andphysical models to investigate optimum operating conditions. A study of oxygen mass transfer caused by multiple top-blown, subsonic gas jets contacting water flowing in a …
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Rare metal resources in polymetallic nodules from the Eastern Equatorial Pacific Ocean
… greatest interest in terms of metal resources in polymetallic nodules. The nodules are enriched (relative to crustal composition) in economically important metals such as Mn, Ni, Cu, Zn, and so-called critical metals such as Co, Rare Earth Elements and Y (REYs). This project involves the …
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Depression of pyrite in polymetallic sulfide flotation using chitosan-grafted-polyacrylamide polymers
… the prediction of the flotation efficiency in polymetallic sulfide systems. </p><p>This research contributes to the advanced efforts to develop “smart and sustainable” processes for the flotation of sulfide minerals in industrial plants”--Abstract, page iii.</p>
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The synthesis and characterisation of polymetallic transition metal complexes towards single-molecule magnets
The synthesis and characterisation of sixteen new complexes are reported. The use of the ligand edte (((HOCH2CH2)2NCH2CH2N(CH2CH2OH)2)), H4L1) has resulted in five new iron complexes. Two Fe6 complexes and an Fe3 complex display non-zero ground states of S = 5 and S = 3 respectively. An Fe12 …
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POLYMETALLIC NODULE ABUNDANCE ESTIMATION USING SIDESCAN SONAR: A QUANTITATIVE APPROACH USING ARTIFICIAL NEURAL NETWORK
… Clipperton Fracture Zone (CCFZ) are pockets of Polymetallic Nodules (PMN). These PMN possess high economic potential as they are rich in minerals such as manganese, nickel, copper and rare earth elements. Quantification of such PMN coverage is important for economic feasibility studies and …
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Sediment plumes and financial modeling in the context of deep-sea polymetallic nodule mining
Deep-sea polymetallic nodule mining commercial operations are close to becoming a reality. In recent years, research activity in the field has substantially increased, but there are yet many technical, environmental and financial challenges to be addressed. This work tackles three critical topics …
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The Synthesis and Photophysical Properties of New Polymetallic Complexes Designed for Use in Photoinitiated Electron Collection
The goal of this research was to develop stereochemically defined multimetallic systems for use as light absorbers and electron donor / light absorber dyads in photoinitiated electron transfer and electron collection. The basis for the stereochemical control was provided by the symmetric bridging …
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Time-Space Relationships between Sediment-Hosted Gold Mineralization and Intrusion-Related Polymetallic Mineralization at Kinsley Mountain, NV
… SHGDs, intrusion-related tungsten skarn, and polymetallic carbonate replacement vein deposits have been mined from Kinsley Mountain, proximal to an Eocene intrusive center. Stratigraphically and structurally controlled SHGDs occur as replacement bodies in Cambrian shelf carbonates and …
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Deep-sea mining : dewatering plumes, vortex-induced vibrations and economic modelling
… issued twenty nine exploration licenses for polymetallic nodules, polymetallic sulphides and polymetallic crusts. The ISA is seeking to approve the exploitation regulations for polymetallic nodules in the next two years, but there are significant research and knowledge gaps that still have to …
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Spatial and Temporal Relationships between Carlin-style Gold and Polymetallic Mineralization at the Deep Cove Gold-Silver Deposit, Lander County, Nevada
… Nevada that contains both Carlin-style and polymetallic mineralization. It has been interpreted as a distal disseminated deposit approximately 1.6 km northeast of the Eocene McCoy Au skarn deposit and adjacent late Eocene quartz monzonite Brown stock. Previous geologic mapping, stable …
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Effect of VRM on a polymetallic sulfide ore and the flotation response as compared to conventional wet and dry rod milling
… in a 3 litre Barker flotation cell. A complex polymetallic sulfide ore containing chalcopyrite (1.3 %), galena (2.4 %) and sphalerite (1.8 %) as the main value minerals and magnetite (68.0 %) and quartz (15.7 %) as dominant gangue minerals was used for the study. The ore was milled to target …
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Tuning the ground and excited state properties of a series of polymetallic tridentate complexes incorporating Ru(II) or Os(II) as the chromophore
… the synthesis of a series of monometallic and polymetallic complexes incorporating the tridentate polypyridyl bridging ligand tpp (where tpp = 2,3,5,6-tetrakis(2-pyridyl)pyrazine) and an investigation of their ground and excited state properties. A series of ruthenium monometallic chromophore …
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The deepest paradox : seafloor mining and its future
… water's surface in geological formations such as polymetallic nodules, ferromanganese crusts, and seafloor massive sulfides is well-established, the biological and ecological profiles of these sites are still actively developing. As a result, the two scientific disciplines - geochemistry and …
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Fundamental Capillary Electrophoresis: An Evaluation of Electrokinetic Sampling
… analysis may be extended to the analysis of polymetallic complexes. Polymetallic complexes are of current interest in the literature due to their complexity and wide range of potential applicability. The first isomeric compound to be studied is [Ru(tpy)CI] 2(bpmi+ (tpy = …
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Iridium (III) photosensitisers for photoredox catalysed carboxylation reactions of ketimines
… industry. Following on from the above, polymetallic transition metal complexes have been promulgated as photocatalysts in processes such as CO2 reduction. These polymetallic photocatalysts were reported to exhibit higher reactivity due to multiple active sites, improved photostability …
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Towards the development of an integrated modelling framework underpinned by mineralogy
… this proposed framework using a case study of a polymetallic sulfide ore flotation circuit. The initial focus in the framework development is on integrating the techno-economic and the environmental aspects of sustainability. Thereafter the framework is used to consider a variety of scenarios …
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Petrography and geochemistry of hydrothermal breccias hosted in the Schrikkloof Formation (Rooiberg Group), north of Modimolle, South Africa
… Bushveld Igneous Complex and is known to host polymetallic Sn-F-REE. The aim and objective of this research is to understand whether the hydrothermal brecciation in the upper Schrikkloof Formation is associated with ore forming processes or not. The study area is located approximately 20 km …
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Effects of heavy metals on the physical activity and survival of freshwater clams
… CDA drainage. In a field-caging assay along the polymetallic gradient in the drainage, clam survival was significantly higher in the unpolluted portion of the drainage (P < 0.001). Laboratory assays of clams exposed to ecologically-relevant doses of zinc and cadmium suggested that the doses …
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Mineral deposition in epithermal deposits formed through flash vaporization and implications for improved understanding of the Arista intermediate-sulfidation epithermal deposit in southern Mexico
… that vein formation at this prolific polymetallic (Au-Ag-Zn-Pb-Cu) deposit was controlled by a relay ramp providing linkage between two adjacent extensional faults. The banded veins at Arista consist of quartz that formed through recrystallization of a noncrystalline precursor. The …
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