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CreatorTitleDescriptionSubjectDate
76 Zhdanov, Michael S.3-D magnetic inversion with data compression and image focusingWe develop a method of 3-D magnetic anomaly inversion based on traditional Tikhonov regularization theory. We use a minimum support stabilizing functional to generate a sharp, focused inverse image. An iterative inversion process is constructed in the space of weighted model parameters that acce...2002-01-01
77 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
78 Brown, Francis HaroldMagnetostratigraphy of the shungura and usno formations, Southwestern Ethiopia: new data and comprehensive reanalysis1978
79 Miller, Jan D.Bismuth dissolution from smelter flue dust residuesEffective bismuth removal from flue dust residues has been accomplished for flue dusts from both zinc and copper smelters. Selective dissolution of bismuth, with respect to silver and lead, can be achieved by the proper manipulation of temperature, sulfuric acid addition and sodium chloride addition...Technique; Distribution; Chloride1976
80 Miller, Jan D.Anisotropic character of talc surfaces as revealed by streaming potential measurements, atomic force microscopy, and molecular dynamics simulationsA study of the interfacial properties of the basal plane and the edge surfaces of talc is described in this paper. The isoelectric-point measured at the two different crystallographic planes by the streaming potential method was found to be similar and exists at about pH 3.0. In the case of the edg...Streaming potential; Scanning electron microscope; Atomic force microscope2006
81 Zhdanov, MichaelResistivity imaging by time domain electromagnetic migration (TDEMM)One of the most challenging problems of electrical geophysical methods is the interpretation of time domain electromagnetic (TDEM) sounding data in the areas with the horizontally inhomogeneous geoelectrical structures. This problem is of utmost importance in mining exploration and environmental stu...1995
82 Brown, Francis HaroldRadiometric dating and tuff mineralogy of omo group depositsThrough the efforts of the Omo Research Expedition and the East Rudolf Research Group, a large number of vertebrate fossils have been collected from the sedimentary deposits near the northern end of Lake Rudolf in Kenya and in the lower Omo valley in Ethiopia. The hominid fossils collected in this a...1976
83 Miller, Jan D.Adsorption mechanisms in nonmetallic activation systemsAdsorption of lead and ferric iron on quurtz and alumina is presented as a function of pH. Only the hydrolyzed species of these metal ions, FeOHt+ and PbOH', adsorb significantly on each of these minerals. Zeta potentials of quartz were measured as a function of pH in the presence of various additio...Ferric iron; Quartz; Lead; Alumina; Adsorption; pH (Chemistry)1970
84 Chapman, David S.; Harris, Robert N.Mid-Latitude (30°-60° N) climatic warming inferred by combining borehole temperatures with surface air temperaturesWe construct a mid-latitude (30°-60° N) reduced temperature-depth profile from a global borehole temperature database compiled for climate reconstruction. This reduced temperature profile is interpreted in terms of past surface ground temperature change and indicates warming on the order of 1°C...Surface air temperature; Surface ground temperature; Borehole temperatures; Geothermal observations2001
85 Brown, Francis HaroldGombe group basalts and initiation of pliocene deposition in the Turkana depression, northern Kenya and southern EthiopiaA little before 4 Ma ago, deposition of Pliocene and Pleistocene strata described as the Omo Group began in the Turkana and Omo basins of northern Kenya and southern Ethiopia. Soon after, basaltic magma erupted as thin lava flows, and intruded as dykes into the oldest Pliocene strata of the basin. T...2004
86 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
87 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
88 Miller, Jan D.Removal of dissolved contaminants from mine drainageEleven mill tailing samples from locations throughout the Rocky Mountain region were tested for their effectiveness in removal of dissolved contaminants from mine drainage . With the exception of the sample of the Blaine Mill tailing, the average capacity of the tailings tested was 9.8 mg of iron p...Mine drainage; Mill tailing; Adsorption; Precipitation; Rocky Mountain Region1972
89 Miller, Jan D.Flotation behavior of digested Asphalt Ridge tar sandThe hot water process for Utah tar sands differs significantly from that used for Canadian tar sands due to inherent differences in respective bitumen viscosities and the nature of bitumen-sand association. These differences have led to the identification of certain design criteria necessary to ac...Tar sand; Utah; Bitumen; Hot water separation; Froth flotation1981
90 Brown, Francis HaroldSome early pleistocene deposits of the lower Omo valley: the Usno formationEarly Pleistocene deposits of the Rudolf Basin have been described by E. Brumpt (Bourg de Bozas, 1903: 107 ff.), Arambourg (1943: 190 ff.), Fuchs (1939), Patterson (1966), and Butzer and Thurber (1969). These include the Omo Beds, first recognized by Brumpt in 1902 and subsequently studied by Arambo...1969
91 Zhdanov, Michael S.Electromagnetic inversion using quasi-linear approximationThree-dimensional electromagnetic inversion continues to be a challenging problem in electrical exploration. We have recently developed a new approach to the solution of this problem based on quasi-linear approximation of a forward modeling operator. It generates a linear equation with respect to ...Quasi-linear approximation; Electromagnetic inversion2000
92 Chapman, David S.; Allis, Richard GeorgeLate Neogene exhumation patterns in Taranaki Basin (New Zealand): evidence from offset porosity-depth trendsTaranaki Basin, New Zealand, is located adjacent to the Australian-Pacific Plate boundary where the tectonic regime changes from dominantly subduction-related to the north to transpression-related along the Alpine Fault to the south. During the Neogene, burial and exhumation varied extensively, in ...Neogene; Uplift; Exhumation; Taranaki Basin; New Zealand1998
93 Miller, Jan D.Characterization of spherical alumina particles obtained by melting in a hydrogen-oxygen flameSpherical oxide particles can be used as mineral fillers, paint pigments, polishing materials and catalysts. They can be prepared using various techniques involving precipitation and spray drying. Melting of particles in a high-temperature flame is a simple technique which produces particles with ...Alumina; Oxides; Hydrogen-oxygen flame2003
94 Miller, Jan D.Mercury control in the cyanidation of gold oresThe control of mercury during gold cyanidation is of particular interest to the gold mining industry. Typically, mercury(II) is released as cyano complexes during leaching and follows gold through the solution concentration and purification step (carbon adsorption and electrowinning or zinc cementat...Gold cyanidation; solvation extraction; selective cementation1996
95 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
96 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
97 Miller, Jan D.Treatment of cyanide by using the Mexican modification of the Merrill-Crowe processCyanide consumption can be a major factor which contributes to operating cost for cyanidation. Also after extraction and recovery of precious metals substancial amounts of cyanide are delivered to tailings ponds which creates environmental problems due to the toxicity of cyanides. In this regard, th...Cyanidation; Merrill-Crowe process; Air-sparged hydrocyclone; Cyanide recovery; Cyanide destruction; Chlorine dioxide1999
98 Miller, Jan D.Selectivity considerations in the amine extraction of gold from alkaline cyanide solutionsIt has been discovered that gold can be extracted from alkaline cyanide solution with primary, secondary, and tertiary amines by adding certain Lewis base modifiers, such as organic phosphorus oxides. Under these circumstances, gold can be extracted at about pH 10, commensurate with the pH of cyan...Gold; Amines; Alkaline cyanide; Extraction1984
99 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
100 Zhdanov, Michael S.Novel approach to the model appraisal and resolution analysis of regularized geophysical inversionThe existing techniques for appraisal of geophysical inverse images are based on calculating the model resolution and the model covariance matrices. In some applications, however, it becomes desirable to evaluate the upper bounds of the variations in the solution of the inverse problem. It is possib...Geophysical inversion; Electromagnetic modeling; Cauchy inequality; Resolution analysis; Lanczos decomposition method; SLDM; Voisey's Bay; 3-D modeling2006
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