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CreatorTitleDescriptionSubjectDate
201 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
202 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
203 Zhdanov, Michael S.Quasi-analytical approximation and series in electromagnetic modelingThe quasi-linear approximation for electromagnetic forward modeling is based on the assumption that the anomalous electrical field within an inhomogeneous domain is linearly proportional to the background (normal) field through an electrical reflectivity tensor ˆλ. In the original formulation of...Electromagnetic modeling; Quasi-linear approximation; Quasi-analytical approximation; Quasi-analytical series2000
204 Zhdanov, MichaelQuasi-analytical boundary condition for three-dimensional finite difference electromagnetic modelingNumerical modeling of the quasi-static electromagnetic (EM) field in the frequency domain in a three-dimensional (3-D) inhomogeneous medium is a very challenging problem in computational physics. We present a new approach to the finite difference (FD) solution of this problem. The FD discretization ...2004-01-01
205 Zhdanov, Michael S.Quasi-linear approximation in 3-D electromagnetic modelingThe Born approximation in electromagnetic (EM) numerical modeling has limited application for solving 3-D electromagnetic induction problems, because in structures with high conductivity contrasts and at high frequencies, this approximation is inaccurate. In this paper, we develop a new and rel...1996-01-01
206 Zhdanov, MichaelQuasi-linear series in three-dimensional electromagnetic modelingWe have recently introduced a quasi-linear (QL) approximation for the solution of the three-dimension(a3l -D) electromagnetic modeling problem. In this paper we discuss an approach to improving its accuracy by considering the QL approximation so f the higher order. This approach can be considered th...1997-01-01
207 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
208 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
209 Chapman, David S.Regional heat-flow variations across the sedimented Juan de Fuca Ridge eastern flank: constraints on lithospheric cooling and lateral hydrothermal heat transportSeafloor heat flow has been estimated continuously along a transect on the sedimented eastern flank of the Juan de Fuca Ridge to provide constraints on the scale and rate of lateral heat and fluid transport in the upper igneous crust, and on the total flux from the young lithosphere beneath. The ...Juan de Fuca Ridge; Seafloor; Lithospheric cooling; Hydrothermal heat transport1999
210 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
211 Miller, Jan D.Removal of volatile organic compounds from contaminated water using air-sparged hydrocyclone stripping technologyThe air-sparged hydrocyclone (ASH) technology offers the unique opportunity to achieve efficient removal of volatile organic compounds (VOCs) from contaminated water at a high specific capacity, more than 100 times that of conventional air stripping technologies. VOC stripping is the first applicati...Air-sparged hydrocyclone; Air stripping; Contaminated water1997
212 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
213 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
214 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
215 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
216 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
217 Zhdanov, Michael S.Rigorous 3D inversion of marine CSEM data based on the integral equation methodMarine controlled-source electromagnetic (MCSEM) surveys have become an important part of offshore petroleum exploration. However, due to enormous computational difficulties with full 3D inversion, practical interpretation of MCSEM data is still a very challenging problem. We present a new approach ...2007
218 Reichler, Thomas J.Role of boundary and initial conditions for dynamical seasonal predictabilityThe importance of initial state and boundary forcing for atmospheric predictability is explored on global to regional spatial scales and on daily to seasonal time scales. A general circulation model is used to conduct predictability experiments with different combinations of initial and boundary co...Atmospheric predictions; Seasonal forecasting; Boundary forcing2002
219 Miller, Jan D.Role of the hydrocarbon chain in anionic flotation of calciteThe response of calcite to flotation with saturated fatty acids and alkyl sulfonates of various chain lengths is presented. The amount of collector required for flotation is shown to decrease systematically with increasing carbon content from 8 to 12-carbon atoms per molecule. This systematic flot...Hydrocarbon chain; Calcite; pH (Chemistry); Carbon1967
220 Jarrard, Richard D.Scientific methods: an online bookThis book was originally intended as ˜How to do science™, or ˜How to be a scientist™, providing guidance for the new scientist, as well as some reminders and tips for experienced researchers. Such a book does not need to be written by the most expert or most famous scientist, but by one who...Science; Process; Method2001
221 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
222 Miller, Jan D.Screening and classificationThe processing of minerals almost invariably involves the reduction in size of the minerals contained in an ore to effect liberation of disseminated values or, in other instances, to effect increased surface area. Separation of solids according to size usually is undertaken to promote maximum produc...Mesh; Mechanical; Separation1973
223 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
224 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
225 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
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