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CreatorTitleDescriptionSubjectDate
76 Jarrard, Richard D.Geophysical properties of oceanic crust at Sites 768 and 770Velocity, density, resistivity, and neutron-porosity logs were recorded in virtually the entire 222-m-thick section of basaltic back-arc crust drilled at Site 768 and through the 106-m section of MORB crust at Site 770. Our analysis of these logs and comparison with measurements on discrete cores pe...1991
77 Jarrard, Richard D.Electrical properties of basalts from Sites 768 and 770Conductivity of 54 basalt samples from ODP Sites 768 and 770 was measured as a function of temperature and fluid salinity. Porosity was also measured for all samples, and cation exchange capacity was measured for 46 of the samples. Porosity measurements indicated that porosity is underestimated fo...1991
78 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
79 Miller, Jan D.Significance of graphitic structural features in gold adsorption by carbonThe nature of surface sites for the adsorption of gold from alkaline cyanide solutions has been investigated using samples of synthetic, highly-oriented pyrolytic graphite (HOPG). This HOPG material offers an idealized graphite structure enabling the independent study of the graphitic basal-plane ...Graphite carbons; Gold; Adsorption1992
80 Brown, Francis HaroldMethods of datingThe fossil record of primates begins in the latest Cretaceous period, so primate palaeontologists are interested in techniques of dating applicable over the past 70 million years. Fossil bones themselves are rarely datable with any precision, and these are mainly of late Pleistocene or Holocene age....1992
81 Miller, Jan D.; Hupka, JanPotential of air-sparged hydrocyclone flotation in environmental technologyAir-sparged hydrocyclone (ASH) flotation is a high capacity flotation technology originally developed in the Department of Metallurgical Engineering at the University of Utah for processing mineral resources. However, the technology has been found to be useful in industrial waste processing, recycli...De-inking; Capacity; Recycling1992
82 Miller, Jan D.Applications of X-ray computed tomography in particulate systemsX-ray computed tomography (CT) is an ideal technique for investigating the internal structure of multiphase materials in a noninvasive and nondestructive manner. CT technology used in conjunction with specialized algorithms and advanced computer facilities can be used to provide quantitative informa...Algorithms; Beam; Intensity1992
83 Miller, Jan D.;Yu, QiangFossil resin, a value-added product from western coalCertain bituminous coals of the western United States are known to contain appreciable quantities of macroscopic fossil resin (resinite). Such resinous coals are found in the states of Arizona, Colorado, New Mexico, Utah, Washington, Wyoming, etc. The Wasatch Plateau coal field in Utah (Figure 1)...Resinite; Solvent refining; Wasatch Plateau; Hydrogenation1992
84 Jarrard, Richard D.Geometry of Pleistocene facies on the Great Barrier Reef outer shelf and upper slope - seismic stratigraphy of sites 819, 820, and 821Seismic stratigraphic analysis of the sedimentary succession intersected in Ocean Drilling Program (ODP) Sites 819, 820, and 821, on the outer shelf and upper slope seaward of the Great Barrier Reef, provides a clear indication of the importance of sediment supply and depositional base-level as two ...1993
85 Miller, Jan D.Solvent extraction reagents for gold recovery from alkaline cyanide solutionsThree different solvent extraction systems for the recovery of gold from alkaline cyanide solutions are reviewed. These include the modified amine extractants in which the basicity of simple alkyl amines, with respect to the aurocyanide anion, is controlled by the addition of alkyl phosphorous ester...Solvents; Extraction; Gold; Alkaline cyanide; Amine extractants; Solvating extractants; Substituted guanidines1993
86 Miller, Jan D.Evaluation of a PC image-based on-line coarse particle size analyzerA PC image-based, on-line coarse particle size analysis system is being developed for the control of crushing and grinding circuits. Initial results had indicated that the system is accurate when tested with irregularly shaped particles which are stationary and do not overlap with each other. Now th...Sampling; Measurements; Analysis1993
87 Jarrard, Richard D.Velocity and density of carbonate-rich sediments from northeastern Australian margin: integration of core and log dataDuring Ocean Drilling Program (ODP) Leg 133, shipboard scientists obtained a remarkable quantity of both core and log measurements of the physical properties of carbonate-rich sediments. This suite of measurements provides a unique opportunity to evaluate the robustness of each measurement technique...1993
88 Jarrard, Richard D.Resistivity/porosity/velocity relationships from downhole logs: an aid for evaluating pore morphologyRelationships between downhole resistivity/velocity logs and porosity styles, controlled by cementation/dissolution/recrystallization, are investigated using core and downhole logging data from the carbonate-rich sediments encountered during Leg 133 of the Ocean Drilling Program (ODP), northeastern ...1993
89 Jarrard, Richard D.Sedimentology and downhole log analysis of Site 820, central Great Barrier Reef outer shelf: the factors controlling Pleistocene progradational and aggradational seismic geometryThe textural and compositional characteristics of the 400 m sequence of Pleistocene wackestones and packstones intersected at Ocean Drilling Program (ODP) Site 820 reflect deposition controlled by fluctuations in sea-level, and by variations in the rate of sediment supply. The development of an effe...1993
90 Miller, Jan D.Surface phase transitions of adsorbed collector molecules as revealed by in-situ FT-IR/IRS spectroscopyIt has been shown by inspection of FT-IR/IRS spectra that the alkyl conformation of adsorbed collectors can be determined. The conformations of adsorbed collectors were interpreted in terms of bulk solution phases of the collectors. Such analysis was performed on the CaF2/oleate, A1203/SDS and KC1/...Oleates; Micellar; In situ analysis; Adsorption1993
91 Miller, Jan D.Multiphase flow characteristics of gas sparged hydrocyclone flotation deinkingA new high-efficiency technology has been developed for flotation deinking of various wastepaper grades. The GSC gas sparged hydrocyclone is a centrifugal device that operates at consistencies of 1 to 3 percent and uses conventional flotation chemistry. Research and development efforts have continue...Wastepaper; Deinking; Gas sparged hydrocyclone flotation deinking1993
92 Miller, Jan D.; Lin, Chen-LuhDevelopment of a PC, image-based, on-line particle size analyzerA PC, image-based, on-line instrument for measuring coarse particle size on a conveyor belt is under development. The hardware and software required to implement such a system are discussed, including the interface for the special image-acquisition hardware. The system concept is given with exampl...1993
93 Jarrard, Richard D.Origin of seismic reflectors within carbonate-rich sediments from northeastern Australian marginWe use continuous velocity records from 12 sites and continuous density records from 9 sites from Ocean Drilling Program (ODP) Leg 133 to examine both direct and indirect controls on seismic reflectors and depth-to-time conversion for the northeastern Australian margin. In these carbonate-rich sedim...1993
94 Miller, Jan D.; Lin, Chen-Luh; Yu, QiangPC image-based analysis system for particle characterization of deinked pulpsA low cost PC image-based particle analysis system is being developed for particle characterization of deinked pulps at the University of Utah. Initial R&D efforts of such an image analysis system were made for on-line particle characterization in the mineral processing field but now it has been fo...Deinking; Paper pulp; Wastepaper; Image-based particle analysis1993
95 Miller, Jan D.; Wan, Rong YuResearch and development activities for the recovery of gold from noncyanide solutionsAlthough most gold production from primary resources is achieved by cyanidation, many research activities have focused on alternative processes using noncyanide lixiviants. Such research has been prompted by environmental concerns and problems associated with the processing of refractory gold ores. ...Activated carbon adsorption; Cementation; Solvent extraction; Ion exchange; Reduction-precipitation; Halide solutions; Thiourea solutions; Lixiviants1993
96 Miller, Jan D.Tar sand pretreatment with diluentImportant aspects of kerosene penetration into tar sand have been investigated. The natural tar sand porosity was measured and used to analyze the performance of the hot water process. Subsequently, pretreatment experiments, using 20-kg tar sand samples (Asphalt Ridge and Whiterocks, Utah) and ker...Tar sand; Kerosene; Porosity; Temperature1993
97 Miller, Jan D.Preliminary evaluation of air-sparged hydrocyclone technology for scavenger flotation of Western phosphatesThe sedimentary western phosphate deposits of Idaho, Montana, Utah, and Wyoming tend to be calcareous and generally carry a significant amount of dolomite along with collophanite. In some cases, such as the Smokey Canyon Mine, Afton, Wyoming, the ore will also contain mudstone, and in this case the ...Collophanite; hydrosizer; scavenger concentrate1993
98 Miller, Jan D.; Lin, Chen-LuhScientific visualization in mineral and material processingScientific visualization is an ideal methodology for investigating complex phenomena that are characterized by large amounts of data. Furthermore, it is invaluable in the study of processes that evolve in time. Scientific visualization relies heavily on computer graphics, image processing and video...Air sparged hydrocyclone flotation; Ball mill grinding; Tomography; Computer graphics1993
99 Chandran, RaviFracture toughness of two Cr2Hf+Cr intermetallic composites as a function temperatureFracture toughness as a function of temperature was evaluated for two Cr2Hf+Cr intermetallic composites, each in two different microstructural conditions. The proeutectic microstructures based on Cr-6.5Hf (at%) showed a significant increase in fracture toughness with an increase from room temperatur...Fracture toughness; Fracture resistance; Intermetallic composites; Proeutectic microstructures; Eutectic microstructures1994
100 Miller, Jan D.;Yu, QiangSolvent refining of coal resin concentratesCertain bituminous coals of the western United States are known to contain appreciable quantities of macroscopic resinite (fossil resin). Such resinous coals are found in the states of Arizona, Colorado, New Mexico, Utah, Washington, Wyoming, etc. Among these, the Wasatch Plateau coal field in ce...1994
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