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CreatorTitleDescriptionSubjectDate
176 Miller, Jan D.; Wan, Rong YuSignificance of carbon properties in the enhanced ferric sulfate leaching of CuFeS2/C aggregatesAcid ferric sulfate solution has been used for heap and dump leaching of low-grade chalcopyrite ores and is being considered as a possible lixiviant for the hydrometallurgical processing of copper sulfide concentrates. For many years, researchers have attempted to explain the leaching behavior of ch...Ferric sulfate; CuFeS2; Particulate carbon1984
177 Zhdanov, MichaelCross-well electromagnetic imaging in three dimensionsIn this paper, we develop a new technique for 3D cross-well electromagnetic tomography, based on an EM borehole survey consisting of a moving vertical magnetic dipole transmitter, located in one or several boreholes, and a tri-axial induction receiver, located in the other boreholes. The method is b...2003
178 Chandran, RaviEvolution of microstructure and phases in in-situ processed Ti-TiB composites containing high volume fractions of TiB whiskersA series of titanium composites, with varying volume fractions of titanium monoboride (TiB) whiskers, were made by mixing various proportions of titanium (Ti) and titanium diboride (TiB2) powders followed by hot pressing. The phases present were identified by x-ray diffraction.Morphology; diffraction; relative intensity1999
179 Miller, Jan D.Study of particle-bubble interaction using atomic force microscopy: current possibilities and challengesStudy of interaction forces between mineral particles and air bubbles is a key to understanding flotation processes. Measurement of such interaction forces has only recently been made possible with the introduction of the atomic force microscope (AFM) and the colloidal probe technique. Using AFM, in...Particle-bubble interaction; Atomic Force Microscopy (AFM); Hydrophobic force; Contact angle; Hydrodynamic force2002
180 Miller, Jan D.Minerals beneficiation in '69 steps up tonnage, engineering, environmental control and automation: size analysis and flotation chemistry highlighted by basic science researchersThe application of computers to the control and study of mineral processing operations such as grinding, classification and notation has created an interest in simulation studies of these operations with mathematical models. Evidence of this interest is confirmed by papers presented at the 1969 Int...Mineral processing; Computer simulations; Mathematical models1970
181 Brown, Francis HaroldDatingThere are basically three lines of investigation that are involved in geochronology ? the dating of rocks and other earth materials. First, there are the physical and chemical dating methods which give us numerical estimates of age. Second, there is the reconstruction of the order of events in sec...1984
182 Miller, Jan D.; Nalaskowski, JakubInteraction forces between silica surfaces in aqueous solutions of poly(ethylene oxide)sAn understanding of forces responsible for the stability of dispersions of colloidal particles when interacting with each other in aqueous solutions is of great interest academically and industrially. When water-soluble polymers are adsorbed onto colloidal particles, various effects on the stabil...Water-soluble polymers; Colloidal particles; Interaction forces2003
183 Miller, Jan D.Determination of Madelung constants for infinite and semi-infinite lattices by direct summationLattice sums for the electrostatic interactions in ionic crystals, first evaluated by Madelung, are now known to high degrees of accuracy. The problem of conditional convergence has been solved either by manipulations of a mathematical model of the lattice, or by directly summing over neutral group...Lattices; Madelung constants1976
184 Brown, Francis HaroldThe evolution of neogene terrestrial ecosystems in EuropeThe Pliocene-Pleistocene chronology of hominid and other vertebrate evolution in East Africa is largely constrained by isotopic dating and regional intercorrelation of volcanic ash layers. Some eruptions were of sufficient magnitude or duration that their widespread tephra dispersal defines a serie...1999
185 Miller, Jan D.Reaction kinetics of bismuth dissolution from lead cake by sulfuric acid leachingLead cake, a zinc smelter flue dust residue, consists primarily of lead sulfate. Characteristic properties of lead cake were determined in order to aid the understanding of reaction mechanisms involved in bismuth removal from lead cake by sulfuric acid digestion. Sp gr (specific gravity) measuremen...Lead cake; Smelter flue; Lead sulphate; Bismuth; Sulfuric acid1978
186 Jewell, PaulCirculation, salinity, and dissolved oxygen in the Cretaceous North American seawayCritical paleoceanographic problems regarding the maximum transgressive phase of the Cretaceous North American seaway have been studied with a three-dimensional ocean circulation model. Four simulations employing minimum and maximum solar insolation winds from the Cretaceous and a wide range of pre...Cretaceous North American Seaway1996
187 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
188 Miller, Jan D.Separation of bitumen from Utah tar sands by a hot water digestion-flotation techniqueTar sand deposits in the state of Utah contain more than 25 billion bbl of in-place bitumen. Although 30 times smaller than the well-known Athabasca tar sands, Utah tar sands do represent a significant domestic energy resource comparable to the national crude oil reserves (31.3 billion bbl). Based ...Tar sand; Utah; Bitumen; Hot water separation; Froth flotation1978
189 Chapman, David S.; Picard, M. DaneHeat flow in the Uinta Basin determined from bottom hole temperature (BHT) dataThe thermal resistance (or Bullard) method is used to judge the utility of petroleum well bottom-hole temperature data in determining surface heat flow and subsurface temperature patterns in a sedimentary basin. Thermal resistance, defined as the quotient of a depth parameter AZ and thermal con...Thermal analysis; Bottom hole temperature1984-04
190 Reichler, Thomas J.Determining the tropopause height from gridded dataA method is presented to determine tropopause height from gridded temperature data with coarse vertical resolution. The algorithm uses a thermal definition of the tropopause, which is based on the concept of a threshold lapse-rate. Interpolation is performed to identify the pressure at which this th...Meteorology and Atmospheric Dynamics: Stratosphere/troposphere interactions; Numerical modeling and data assimilation; Meteorology; Atmospheric Dynamics: General circulation2003
191 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
192 Miller, Jan D.Axial flow reversal and its significance in air-sparged hydrocyclone (ASH) flotationIn recent years the potential of air-sparged hydrocyclone (ASH) flotation for fine coal cleaning has been demonstrated both in pilot plant testing and in a plant-site demonstration program. Further improvements in the ASH technology will depend, to some extent, on improved understanding of the co...Flotation; zero axial velocity; computational fluid dynamics1995
193 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
194 Chapman, David S.Reply to comment by T.J. Osborn and K. R. Briffa on "Mid-Latitude (30?-60?N) climatic warming inferred by combining borehole temperatures with surface air temperatures"We thank Osborn and Briffa [2002] for their comment regarding our use of the climatic reconstruction of Overpeck et al. [1997]. We [Harris and Chapman, 2001] had taken a proxy, Arctic wide summer-weighted annual temperature reconstruction [Overpeck et al., 1997], given in dimensionless sigma units (...Surface air temperature; Ground surface temperature; Borehole temperatures; Geothermal observations; Heat transfer2002
195 Miller, Jan D.Nonsulfide flotation technology and plant practiceThere are hundreds of nonsulfide mineral flotation plants throughout the United States, and most have a plant design that depends upon the specific ore characteristics and the market specifications for their product. There is no common thread of technology between the design and processing of diffe...Flotation; Minerals; Processing plants2002
196 Miller, Jan D.; Herbst, John A.; Lin, Chen-LuhDevelopment of a multicomponent-multisize liberation modelThis paper is concerned with the development of a kinetic model for mineral liberation by grinding. Existing population balance size reduction models are extended to include two minerals with an arbitrary number of locked particle fractions. The validity of this approach to liberation modelling is d...Population balance; size reduction; liberation; grinding model1985
197 Miller, Jan D.Importance of bitumen viscosity in the hot-water processing of domestic tar sandsThe separation efficiency of the hot water digestion-flotation technique used for bitumen recovery from various domestic tar sands was evaluated. Bitumen viscosity was found to be the most important tar sand property in determining the success of the bitumen separation. Bitumen viscosity of the tar ...Tar sand; Bitumen viscosity; Flotation; Hot-water processing1983
198 Zhdanov, Michael S.Parameter estimation for 3-D geoelectromagnetic inverse problemsParameter estimation in geoelectromagnetics aims to obtain the most important parameters of a well-defined conductivity model of the Earth. These parameters are features of typical geological structures, such as depth and size of conductive or resistive targets, angle of dike inclination and its le...1999-01-01
199 Brown, Francis HaroldCorrelation of tephra layers from the Western Rift Valley (Uganda) to the Turkana Basin (Ethiopia/Kenya) and the Gulf of AdenFour volcanic ashes have been mapped in Albertine Group strata (Warwire, Kaiso Village and Nyabusosi Formations) Western Rift Valley, Uganda. Three of these tuffs have geochemical fingerprints similar to tuffs in the Turkana Basin (Ethiopia, Kenya), in Afar (Ethiopia) and the Gulf of Aden, permitti...1991
200 Brown, Francis HaroldMagnetostratigraphy of the shungura and usno formations, lower Omo Valley, Ethiopia1976
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