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CreatorTitleDescriptionSubjectDate
151 Chapman, David S.; Harris, Robert N.Stop-go temperature logging for precision applicationsWe describe a new field procedure for stop-go temperature logging of boreholes that attains millikelvin precision. Temperature is recorded continuously throughout the entire log, but the logging probe is held stationary for a fixed time at discrete depth intervals. Equilibrium temperatures at the di...Temperature logging; Boreholes; Stop-go logging method2007
152 Miller, Jan D.Dispersed oil impact on froth stability in flotationFoam stability in flotation has been studied for more than half of the last century, however, the mechanisms responsible for the defoaming action of many presently used reagents are not completely understood. This research presents oil flotation data, which may be used in the evaluation of aqueous ...Particles; Defoaming; Surfactants2001
153 Miller, Jan D.Effect of ink types and printing processes on flotation deinkingExamination of ink types reveals that newsprint oil-based offset-cold and offset-heat inks contain substantial oil (45 to 60%) and resin (5 to 35%), water-based ink contains water (40%) and resin (polystyrene, 30%). These inks are liquids with densities around 1 g/cm3, having various viscosities...Toners; Inks; Photocopying; Laser printing; Flotation; Deinking; Recycling; Office waste; Hyrdophobicity1997
154 Miller, Jan D.Metal ion activation in xanthate flotation of quartzQuartz cannot be floated with potassium amyl xanthate as collector at any pH. Complete flotation is achieved with certain minimal additions of amyl xanthate and Pbtt from pH 5.8 to 8.5 and with amyl xanthate and Znt+ from pH 7.5 to 8.1. The active species of these metal ions responsible for activ...pH (Chemistry); Xanthate flotation; Metal ions1965
155 Miller, Jan D.; Lin, Chen-LuhParticle size distribution for copper heap leaching operations as established from 3D mineral exposure analysis by X-ray microCTThe particle size distribution (PSD) for copper heap leaching is an important consideration in the design and operation of any copper heap leaching facility. High-resolution 3D X-ray microtomography (XMT) can be used for the direct determination of the percentage of exposed valuable mineral grains i...Particle size distribution; Leaching; X-ray microtomography2003
156 Miller, Jan D.Hydrophobicity and elemental composition of laser-printed toner filmsLaser-printed toner films on a polymer support were treated with alkaline (NaOH) aqueous solutions at elevated temperature (80-85° C). These toner films were examined with a sessile-drop contact-angle measurement technique in order to establish the hydrophobicity of the toner surface. Also, X-ray p...Ink; Fibers; Deinking1996
157 Brown, Francis HaroldThe lower Omo basinThe boundaries of the Lower Omo Basin have been mapped by Fuchs (1939) and by Butzer (1970, 1971) in a general way. The structural features and physiography of the eastern and central part of the Lower Omo Basin are best expressed on the maps of Davidson et al. (1973). Walsh and Dodson (1969) have m...1983
158 Brown, Francis HaroldGeological development of the Omo-Turkana Basin during the pliocene and pleistocene epochsPliocene and Pleistocene deposits of the Omo-Turkana Basin extend from 6?N latitude to about 2?N latitude (-450 km), and laterally from about 35.5?E to 36.5?E. Sediments are brought to the basin by the Omo River which rises in Ethiopia, and by the Turkwel and Kerio Rivers which rise in Kenya and Uga...2004
159 Miller, Jan D.Bench scale flotation of sedimentary phosphate rock with hydroxamic acid collectorsIt has been discovered that water insoluble alcoholic solutions of alkyl hydroxamic acids serve as selective collectors for the flotation of phosphate mineral resources. The effectiveness of the new collector chemistry has been demonstrated by the results from single stage bench scale flotation exp...Flotation; Insoluble collectors; Hydroxamic acid; Alcohol; Phosphate rock; High solids conditioning; Particle size2002
160 Miller, Jan D.Pilot-plant evaluation of a water insoluble hydroxamic acid collector for single stage flotation of Florida phosphate rockRecent laboratory results have demonstrated that selective flotation of phosphate rock can be achieved in a single stage with improved separation efficiency when compared to the standard double float process. The new reagent chemistry is based on the use of a water insoluble alcoholic solution of ...Phosphate rock; Flotation; Double float; Separation2006
161 Rajamani, RajOnline SAG mill pulse measurement and optimization semi-annual technical progress reportThe grinding efficiency of semi autogenous milling or ball milling depends on the tumbling motion of the total charge within the mill. Utilization of this tumbling motion for efficient breakage of particles depends on the conditions inside the mill. However, any kind of monitoring device to measure...2006
162 Garrett, Timothy J.Gains in economic energy efficiency as the impetus for increasing atmospheric carbon dioxideGrowth of anthropogenic carbon dioxide (CO2) emissions is frequently diagnosed as a product of population, per capita economic production, the energy intensity of economic production (or inverse of its energy efficiency), and the carbon intensity of energy. This paper introduces an alternative, p...carbon dioxide, energy efficiency, economics2007-12-17
163 Miller, Jan D.Evaluation of a CT-based coal washability analysis system under simulated on-line conditionsThe appropriate software and hardware necessary to adapt an X-ray CTanalyzerfor the determination of coal washability was developed and successfully tested for well-characterized samples under laboratory conditions. Evaluation of the CT-based analyzer under simulated on-line conditions is also prese...Coal washability; Computer simulation; X-ray CT analysis2002
164 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
165 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
166 Miller, Jan D.Bubble generation in swirl flow during air-sparged hydrocyclone flotationAir-sparged hydrocyclone (ASH) flotation is a new, promising technology, and, since its conception, numerous applications have been successfully tested. Nevertheless, research and development efforts have continued to improve the technology with respect to operating conditions and design considerati...Air-sparged hydrocyclone flotation; Bubble size; Process variables1996
167 Jarrard, Richard D.Exceptionally preserved jellyfishes from the Middle CambrianCnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnida...Jellyfishes; Metazoan evolution; Jellyfish fossils; Marjum Formation; Utah; Middle Cambrian2007-10-31
168 Miller, Jan D.Arsenic removal from contaminated watersArsenic is a contaminant at 781 of 1,430 sites identified on the National Priorities List and in mining and mineral processing wastewaters, smelter wastes, and sites for manufacture of semiconductors, petroleum products, wood preservatives, animal feed additives, and herbicides. Arsenic affects abo...Arsenic; Arsenate; Arsenite; Microbial; Activated carbon; Magnetic activated carbon; Biomac2005
169 Brown, Francis HaroldChronologyThe boundaries of the Lower Omo Basin have been mapped by Fuchs (1939) and by Butzer (1970, 1971) in a general way. The structural features and physiography of the eastern and central part of the Lower Omo Basin are best expressed on the maps of Davidson et al. (1973). Walsh and Dodson (1969) have m...1983
170 Miller, Jan D.Direct three-dimensional liberation analysis by cone beam x-ray microtomographyLiberation of valuable minerals during size reduction is an important aspect of mineral processing technology. In practice, most quantitative information on liberation is based on the application of stereological theorems for the analysis of image data from two-dimensional polished sections. On th...Mineral processing; Cone beam x-ray; Microtomography1997
171 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
172 Fernandez, Diego P.Deep-sea scleractinian coral age and depth distributions in the Northwest Atlantic over the last 225,000 yearsDeep-sea corals have grown for over 200,000 yrs on the New England Seamounts in the northwest Atlantic, and this paper describes their distribution both with respect to depth and time. Many thousands of fossil scleractinian corals were collected on a series o f cruises from 2003- 2005; by contrast,...Desmophyllum dianthus; Scleractinian coral; Seamounts; Northwest Atlantic2007
173 Miller, Jan D.Microscopic observations of bitumen spreading at gas bubble surfacesBitumen spreading at gas bubble surfaces was observed through a stereoscopic microscope for Whiterocks oil sand samples submerged in alkaline solutions. This phenomenon was also observed for model systems where air bubbles were placed al the surface of bitumen-coated quartz slide. Finally, the film ...Hydrophobic minerals; Oil sand; Gas bubbles1995
174 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
175 Chandran, RaviMicrostructure and thermal conductivity of thermal barrier coatings processed by plasma spray and physical vapor deposition techniquesThe temperature dependence of the thermal conductivity of multilayer coatings made by a plasma spray technique as well as some coatings made by physical vapor deposition (PVD) was investigated. The multilayer coatings consisted of a varying number of layers of AI2O3 and Zr02 stabilized by 8%Y203. Pl...Thermal barrier coatings; Multilayer coatings; Plasma spray technique1996
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