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CreatorTitleDescriptionSubjectDate
51 Miller, Jan D.Gold flotation from Colorado River sand with the air-sparged hydrocyclonePilot-scale tests indicate that effective concentration of fine gold from Colorado River sands can be achieved by flotation with the air-sparged hydrocyclone. The fine sands (55% -kOQ mesh and 0 01 opt *) from gravity concentration were processed with a 5-cm air-sparged hydrocyclone (capacity -1.0 t...Gold; Hydrocyclones; Sand; Flotation1986
52 Miller, Jan D.Methodology for detailed liberation analysis in mineral processing technologyA transformation equation can be used to describe the relationship between the one, two and three dimensional information regarding the composition of mineral particles of specified size. Linear or areal grade distributions f(gi) can be transformed to an estimate of the volumetric grade distribution...Volumetric grade; Grade; Distribution1986
53 Brown, Francis HaroldMagnetostratigraphy of the Koobi Fora Formation, Lake Turkana, KenyaThe Koobi Fora Formation, a Pliocene and Pleistocene sequence of sedimentary deposits northeast of Lake Turkana, has yielded numerous fossils and stone artifacts of early hominids. Stratigraphic correlation of the hominid-bearing deposits throughout the Turkana region was established primarily by th...1986
54 Chandran, RaviNear threshold fatigue crack growth behaviour of a high strength steel: the effect of prior austenitic grain sizeNear threshold fatigue crack propagation behaviour of a high strength steel under different prior austenitic grain sizes with constant tensile properties was investigated. Attention has been paid to the observation of facture modes at thresh-; old in different grain sizes. The observations indicate ...High strength steel; Crack growth; Austenitic grain size1987
55 Miller, Jan D.Fluoride activation in oleate flotation of collophaniteFluoride activation has been evaluated by Hallimond tube flotation of collophanite in terms of fluoride concentration, conditioning time, pH, and temperature. The results reveal that efficient oleate flotation of collophanite can be achieved by fluoride activation. Experimental results of fluoride...Fluoride; Oleate; Collophanite; Flotation; Calcium; Chemisorption1987
56 Miller, Jan D.Zinc-dust cementation of silver from alkaline cyanide solutions - analysis of plant dataThe direct recovery of precious metals from alkaline cyanide solution is frequently accomplished by the well-established Merrill-Crowe process involving zinc-dust cementation. This is particularly true for silver. Plant data from two operations are presented and analyzed in terms of intrinsic reacti...Zinc-dust; Silver; Alkaline cyanide; Merrill-Crowe1988
57 Miller, Jan D.Development of the air-sparged hydrocyclone - a swirl-flow flotation columnFrom laboratory research activities during the past five years, it is now evident that effective flotation separations can be achieved with the high-capacity air-sparged hydrocyclone.Air-sparged hydrocyclone; Froth core1988
58 Miller, Jan D.Air sparged hydrocyclone for fine coal flotationThe cleaning of fine coal to achieve compliance specifications generally is a challenging problem for coal preparation engineers. Gravity separation techniques are limited with regard to capacity/ efficiency considerations, and the most promising process alternative seems to be flotation, the u...Microbubble; Compliance; Bituminous1988
59 Chapman, David S.Inversion of bottom-hole temperature data: the Pineview field, Utah-Wyoming thrust beltThe present day temperature field in a sedimentary basin is a constraint on the maturation of hydrocarbons; this temperature field may be estimated by inverting corrected bottom-hole temperature (BHT) data. Thirty-two BHTs from the Pineview oil field are corrected for drilling disturbances by a Ho...Thermal analysis; Bottom hole temperature; Inversion; Pineview Oil Field1988-05
60 Jarrard, Richard D.Seismic stratigraphy and history of deep circulation and sediment drift development in Baffin Bay and the Labrador SeaDrilling results and seismic-reflection records at and across Ocean Drilling Program (ODP) Sites 645 (western Baffin Bay), 646, and 647 (Labrador Sea) provide important constraints on the history of deep-water circulation and sedimentation in response to Cenozoic climatic change, as well as the tect...1989
61 Jarrard, Richard D.The magnetostratigraphy of ocean drilling program leg 105 sedimentsDuring Leg 105 of the Ocean Drilling Program, a series of 11 holes was drilled at three sites along a north-south transect in Baffin Bay and the Labrador Sea. Intermittent recovery and drilling disturbance, resulting in part from the harsh weather conditions encountered, hampered magnetostratigraph...1989
62 Jarrard, Richard D.Velocity and density of sediments of Eirik Ridge, Labrador Sea: control by porosity and mineralogyA 767-m section of late Neogene (0-8 Ma) terrigenous sediments was cored at Ocean Drilling Program (ODP) Site 646. Continuous downhole geophysical logs, 161 laboratory measurements of core porosity and density, and 63 laboratory measurements of core velocity are used to analyze in detail the effects...1989
63 Miller, Jan D.Selective flotation of fossil resin from Wasatch Plateau high-volatile bituminous coalCertain bituminous coals are known to contain appreciable quantities of natural fossil or subfossil resin. Such resinous coals are found in the western US, particularly the Wasatch Plateau coalfield of UT. Some of the seams in this field contain an average of 5% resin. This fossil resin has been r...Bituminous coal; Wasatch Plateau; Resin1989
64 Miller, Jan D.Infrared spectroscopy for in-situ characterization of surface reactionsInfrared spectroscopy has been one of the most useful experimental techniques for the analysis of surface reactions in flotation systems, including surface alteration and surfactant adsorption reactions. With the advent of Fourier transform infrared (FTIR) spectrometers, many low-energy throughpu...Reflection; Flotation; Measurements1989
65 Miller, Jan D.Quantitative in-situ analysis of collector adsorption reactions by FTIR internal reflection spectroscopyResearchers in flotation chemistry have long sought to describe collector adsorption phenomena in greater detail including kinetics, orientation and interactions between adsorbed species. Now a quantitative description can be made in-situ using FTIR internal reflection spectroscopy. Details of the a...Fourier transform infrared spectrometers1989
66 Jarrard, Richard D.Sedimentary response to paleoclimate from downhole logs at Site 693, Antarctic Continental MarginThe first well logs collected below the Antarctic circle were obtained during Leg 113 at Site 693 on the Dronning Maud Land Margin (Antarctica) in the Weddell Sea. Gamma-ray, resistivity, and sonic logs were collected between 108.0 and 439.0 mbsf. The downhole logs show good agreement with the data...1990
67 Miller, Jan D.; Lin, Chen-LuhFlotation recovery of high-purity gibbsite concentrates from a Brazilian bauxite oreRecently research efforts have been made to obtain a high-purity gibbsite concentrate, suitable for first-class alumina refractories, from a Brazilian bauxite ore containing gibbsite (50%), quartz (35%),and kaolinite (15%). Detailed polished-section microprobe analysis was used to describe the ...Gibbsite; Alumina1990
68 Miller, Jan D.Molybdenite flotation from copper/molybdenum concentrates by ozone conditioningTypically, rougher molybdenite flotation and recovery from bulk copper/molybdenum concentrates involves the use of alkalisulfides, Nokes reagents, cyanides, oxidants, and/or thermal treatment to depress copper sulfide minerals. The bulk copper/molybdenum feed generally varies from 0.2% Mo to 1.0% M...Molybdenum; Copper; Flotation; Ozone conditioning1990
69 Miller, Jan D.Spectroscopic analysis of passivation reactions for carbonaceous matter from carlin trend oresAbstract. Three different refractory carbonaceous gold ores from the Carlin operation in northeastern Nevada were investigated to characterize the effect of passivation treatments on the nature of the carbonaceous material. The carbonaceous material was chemically isolated from the ores and pass...Gold; Chlorine; Cyanidation1990
70 Jarrard, Richard D.Milankovitch paleoceanographic cycles in geophysical logs from ODP Leg 105, Labrador Sea and Baffin BayOcean Drilling Program (ODP) Sites 645 and 646, in Baffin Bay and the Labrador Sea, respectively, were logged following drilling during Leg 105. Geophysical logs in ODP drill sites yield long, continuous records of sedimentary sequences and thus provide the opportunity for examining evidence of peri...1990
71 Jarrard, Richard D.Results of borehole televiewer observations in the Celebes and Sulu SeasBorehole televiewer data were collected during Ocean Drilling Program Leg 124 to investigate stress orientations in the Sulu and Celebes sea basins. At Site 768C, in the Sulu Sea, televiewer logs were collected from 809-870 and 950-1250 meters below sea floor (mbsf). At Site 770C, in the Celebes Se...1991
72 Miller, Jan D.Search for adsorbed gold cyanide on carbon surfacesThe mechanism of adsorption of gold from alkaline cyanide solutions by carbon has been the subject of much research over the past decade. In this paper, the nature of the gold cyanide adsorption phenomenon is investigated, particularly with respect to carbon substrates and associated surface adsorpt...Gold cyanide; spectrometers; X-ray photoelectron spectroscopy1991
73 Jewell, PaulGeochemistry and paleoceanographic setting of Central Nevada bedded baritesThe bedded barite deposits of central Nevada are hosted by rocks of the Roberts Mountains allochthon and constitute the largest barite reserves in North America. Detailed geochemical studies of three barite deposits in the Devonian Slaven Chert indicate that rocks surrounding the barite have elevate...Bedded barites; Roberts Mountains allochthon; Late Devonian1991
74 Jarrard, Richard D.Geochemical results from wireline logs in the Celebes Sea, Sites 767 and 770 of Leg 124Geochemical well logs were obtained at ODP Sites 767 and 770 in the Celebes Sea. The log data obtained at sea have been corrected for borehole size changes, the effects of drilling fluids, and logging-speed variations. The processed logs are then used to calculate the amounts of the three major ra...1991
75 Jarrard, Richard D.High-resolution geochemical variations at Sites 723, 728, and 731: a comparison of X-ray fluorescence and geochemical logsGeochemical logging is a routine part of the Ocean Drilling Program, yet the reliability of ODP geochemical logs has rarely been evaluated quantitatively. On ODP Leg 117, geochemical logs were obtained at Sites 723, 728, and 731. We report here an evaluation of ODP geochemical log quality based on h...1991
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