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CreatorTitleDescriptionSubjectDate
251 Miller, Jan D.Thermogravimetric/Mass spectrometric (TG/MS) characterization of toner particles from photocopied wastepaper and the impact of these features on flotation deinkingFlotation deinking of photocopies from office waste is known to be much more difficult than the flotation deinking of newsprint. In this regard, research has been undertaken to better understand the phenomena which account for the poor efficiency in the flotation deinking of such office waste. Durin...Photocopied paper; Recycling; Deinking; Flotation; Thermal decomposition; Thermogravimetry; Mass spectrometry; Differential scanning calorimeter; Toner particles1995
252 Miller, Jan D.Thiocarbonate collectors in pyrite flotation ? fundamentals and applicationsRecent results from electrochemical measurements demonstrate that trithiocarbonate (TTC) collectors are more readily oxidized to their corresponding dithiolates than the dithiocarbonate/xanthate (DTC) collectors. Based on the traditional analysis of collector adsorption, trithiocarbonates might then...Trithiocarbonate; xanthate; nitrogen2003
253 Miller, Jan D.Thiourea-thiocyanate leaching system for goldThe leaching of gold in thiourea-thiocyanate solutions has been studied by the rotating-disk technique using ferric sulfate as oxidant. The effects of initial concentrations of ferric, thiourea (Tu) and thiocyanate as well as temperature and pH values on gold leaching rates were studied. An initial ...2010-01-01
254 Miller, Jan D.Three dimensional analysis of particulates in mineral processing systems by cone beam X-ray microtomographyIn general, X-ray-computed tomographic (CT) techniques are capable of providing three-dimensional images of the internal structure of opaque materials in a nondestructive manner. The unique cone beam geometry allows acquisition of all two-dimensional projections with only one rotation of the sample,...Cone beam CT; X-ray microtomography; Liberation analysis; Particle shape; Heap leaching; Exposure analysis; Coal washability2004
255 Zhdanov, MichaelThree-dimensional inversion of large-scale EarthScope magnetotelluric data based on the integral equation method: geoelectrical imaging of the Yellowstone conductive mantle plumeInterpretation of the EarthScope MT (magnetotelluric) data requires the development of a large-scale inversion method which can address two common problems of 3D MT inversion: computational time and memory requirements. We have developed an efficient method of 3D MT inversion based on an IE (integ...2011
256 Zhdanov, MichaelThree-dimensional quasi linear electromagnetic inversionOne of the most challenging problems of electromagnetic (EM) geophysical methods is developing three-dimension(a3l- D) EM inversion techniques. This problem is of utmost importance in practical applications because of the 3-D nature of the geological structures.T he main difficulties in 3-D inversio...1996-01-01
257 Zhdanov, Michael S.Three-dimensional quasi-linear electromagnetic modeling and inversionThe quasi-linear (QL) approximation replaces the (unknown) total field in the integral equation of electromagnetic (EM) scattering with a linear transformation of the primary field. This transformation involves the product of the primary field with a reflectivity tensor, which is assumed to vary slo...1999-01-01
258 Zhdanov, Michael S.Three-dimensional regularized focusing inversion of gravity gradient tensor component dataWe develop a new method for interpretation of tensor gravity field component data, based on regularized focusing inversion. The focusing inversion makes its possible to reconstruct a sharper image of the geological target than conventional maximum smoothness inversion. This new technique can be eff...Focusing inversion; Gravity gradient; Gravity gradiometry2004
259 Brown, Francis HaroldTiming of volcanism and evolution of the northern Kenya RiftThe northern Kenya Rift is bounded on the west by uplands of Turkana which comprise horst-like blocks that include metamorphic basement rocks, locally overlain unconformably by the Cretaceous Lubur Sandstone, in turn overlain by predominantly volcanic sequences in which relatively thin sedimentary p...2009
260 Miller, Jan D.Toner ink particle morphology in air-sparged hydrocyclone flotation deinkingA series of pulping and flotation deinking tests were performed using a pilot-scale air-sparged hydrocyclone (ASH) flotation cell and a toner ink printed furnish. Microscopy studies indicate ink particles in both the flotation accepts and rejects are relatively flat. Many of the ink particles ap...Elongation; Cyclone; Particles1996
261 Hu, LihaiTrace elements in the hairStudy of uneven distribution of trace elements in elephant hair and compare the result with animal horns.2013
262 Solomon, Douglas KipTracer applications of noble gas radionuclides in the geosciencesNoble gas radionuclides, including 81Kr (t1/2 = 229,000 yr), 85Kr (t1/2 = 10.8 yr), and 39Ar (t1/2 = 269 yr), possess nearly ideal chemical and physical properties for studies of earth and environmental processes. Recent advances in Atom Trap Trace Analysis (ATTA), a laser-based atom counting method...2014-01-01
263 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
264 Miller, Jan D.Trithiocarbonates for PGM flotationSmall replacements of C12-trithiocarbonate (C12-TTC) for dithiocarbonate DTC)/dithiophosphate (DTP) in a reagent suite for the flotation of platinum group metals (PGM) have significantly improved the rejection of gangue. Coupled to this is an improvement in kinetics, grade and recovery of PGMs. In ...2006
265 Zhdanov, MichaelTwo-dimensional magnetotelluric inversion of blocky geoelectrical structuresThis paper demonstrates that there are alternative approaches to the magnetotelluric (MT) inverse problem solution based on different types of geoelectrical models. The traditional approach uses smooth models to describe the conductivity distribution in underground formations. In this paper, we pres...2002-01-01
266 Reichler, Thomas J.; Kim, JunsuUncertainties in the climate mean state of global observations, reanalyses, and the GFDL climate modelClimate research relies on realistic atmospheric data over long periods of time. Global reanalyses or observations are commonly used for this type of work. However, the many problems associated with both the reanalyses and observations cast doubts on the reliability of such data for climate appli...Climate; Atmospheric data; Reanalyses2008
267 Zhdanov, Michael S.Underground imaging by frequency-domain electromagnetic migrationA new method of the resistivity imaging based on frequency-domain electromagnetic migration is developed. Electromagnetic (EM) migration involves downward diffusion of observed EM fields whose time flow has been reversed. Unlike downward analytical continuation, migration is a stable procedure tha...1996-01-01
268 Miller, Jan D.Understanding the agglomeration behavior of nickel laterite and gold ores using statistical design of experimentsThe drum agglomeration of nickel laterite and gold ores has been optimized through the design of experiments (DOE) using a Taguchi L16 (45) orthogonal array to determine the optimum conditions for maximizing average agglomerate size and minimizing the amount of fines. The effects of controllable ope...2014-01-01
269 Miller, Jan D.Understanding the role of ion interactions in soluble salt flotationThere is anecdotal evidence for the significant effects of salt ions on the flotation separation of minerals using process water of high salt content. Examples include flotation of soluble salt minerals such as potash, trona and borax in brine solutions. Although some of the effects are expected, so...2011-01-01
270 Reichler, Thomas J.; Staten, Paul W.Use of radio occultation for long-term tropopause studies: uncertainties, biases, and instabilities.Research suggests that changes in tropopause structure can both indicate and impact changes in the global climate system. The Global Positioning System radio occultation (RO) technique shows tremendous potential for monitoring the global tropopause due to its precision, temporal consistency, and ...Radio occultation; Tropopause; Climate2007
271 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
272 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
273 Thorne, Michael S.Viterbi sparse spike detectionAccurate interpretation of seismic traveltimes and amplitudes in the exploration and global scales is complicated by the band-limited nature of seismic data. We discovered a stochastic method to reduce a seismic waveform into a most probable constituent spike train. Model waveforms were constructed ...2013-01-01
274 Miller, Jan D.Water at interfaces - some recent experimental results from surface spectroscopyFundamental aspects of interfacial phenomena in aqueous systems are determined by the properties of interfacial water It has become evident that interfacial water must be characterized spectroscopically in order to explain the recently identified non DLVO forces observed by atomic force microscopy a...Interfacial water; Surface spectroscopy; Hydrophobic surfaces; Hydrophilic surfaces; Hydrogen bonding; FTIR/IRS; SFG; Spectroelectrochemistry; Non-DLVO forces; Atomic force microscopy1996
275 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
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