51 - 75 of 152
Number of results to display per page
CreatorTitleDescriptionSubjectDate
51 Miller, Jan D.; Nalaskowski, JakubFlotation chemistry and technology of nonsulfide mineralsThe dimensions of nonsulfide flotation technology extend in many directions, as might be expected from the diversity of the mineral classes, which include soluble salt minerals (potash, borax, and trona), semisoluble salt minerals (phosphate minerals, fluorite, calcite, and barite), and insoluble ox...Flotation; Insoluble collectors; Salt minerals; Nonsulfide minerals2007
52 Miller, Jan D.Hydrophobic character of semisoluble salt minerals with oleate as collectorThe effects of temperature, oxygen partial pressure, and solution chemistry can have a significant effect on the hydrophobic character of semisoluble salt minerals with adsorbed oleate. Measurements of bubble-attachment time and contact angle reveal the sensitivity of these hydrophobic surfaces to c...Flotation; Solution; Oleate1984
53 Chandran, RaviNear threshold fatigue crack growth behaviour of a high strength steel: the effect of prior austenitic grain sizeNear threshold fatigue crack propagation behaviour of a high strength steel under different prior austenitic grain sizes with constant tensile properties was investigated. Attention has been paid to the observation of facture modes at thresh-; old in different grain sizes. The observations indicate ...High strength steel; Crack growth; Austenitic grain size1987
54 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
55 Miller, Jan D.Air-sparged hydrocyclone (ASH) technology for cyanide recoveryAn air-sparged hydrocyclone (ASH) mobile system was evaluated for continuous stripping and recovery of cyanide (the AVR process) from process water at a gold plant site. The ASH unit performed exceptionally well as an absorber. HCN was absorbed from the gas phase in a single pass with an efficiency...Cyanide recovery; Air-sparged hydrocyclone; Gold processing; Process water2005
56 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
57 Miller, Jan D.Characterization of interfacial water at hydrophilic and hydrophobic surfaces by in situ FTIR/internal reflection spectroscopyIn-situ FTIR/internal reflection spectroscopy (FTIR/IRS) has been used to spectroscopically characterize interfacial water near hydrophilic (silicon single crystal) and hydrophobic (polymer-coated germanium single crystal) surfaces. Interfacial water was examined spectroscopically over certain dista...Interfacial water; hydrophilic surfaces; Hydrophobic surfaces; Internal reflection spectroscopy; Silicon crystals; Germanium crystals1995
58 Miller, Jan D.Electrochemistry in silver catalysed ferric sulfate leaching of chalcopyritePrevious investigations have demonstrated the catalytic effect of silver additions in the ferric sulfate leaching of chalcopyrite. CuFeS2 + 4Fe+3 > Cu++ + 5Fe++ + 2S° The enhanced rate of leaching was found to be due to the formation of an intermediate Ag2S film which forms on the CuFeS2 surf...Reaction; Sulfur; Elemental1981
59 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
60 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
61 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
62 Miller, Jan D.Dimethyl ether - a new synthetic fuel commodity and chemical building blockDimethyl ether (DME) is recognized as a potential next-generation, environmentally benign commodity for energy storage and distribution, as well as a momentous chemical building block. DME can be produced at a competitive price from synthesis gas conveniently generated from a variety of carbon-cont...Dimethyl ether; DME; Energy carrier; Energy commodity; Diesel fuel2005
63 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 cyani...Gold; Amines; Alkaline cyanide; Extraction1984
64 Miller, Jan D.Critical review of wetting and adhesion phenomena in the preparation of polymer-mineral compositesThe wetting behavior of liquid polymers at solid surfaces and the adhesion forces involved at polymer-filler interfaces should always be considered in the preparation of high-quality polymer composites, including those made with mineral fillers. Spontaneous polymer spreading over the filler surface...Polymer-minerals; Composites; Wetting; Adhesion1995
65 Miller, Jan D.Selective flotation of fossil resin from Wasatch Plateau high-volatile bituminous coalCertain bituminous coals are known to contain appreciable quantities of natural fossil or subfossil resin. Such resinous coals are found in the western US, particularly the Wasatch Plateau coalfield of UT. Some of the seams in this field contain an average of 5% resin. This fossil resin has been r...Bituminous coal; Wasatch Plateau; Resin1989
66 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
67 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
68 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
69 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
70 Miller, Jan D.Interaction forces between ink particles, cellulose fibers and mineral fillers as determined by AFMRecycling of wastepaper is an important industrial activity for the conservation of our natural resources. Wastepaper is mostly generated from newspaper and office waste (from photocopiers and laser printers) [1]. One important step in wastepaper recycling is the separation of ink from cellulose...Solution; Wastepaper; Chemistry1996
71 Miller, Jan D.Flotation behavior of chromium and manganese mineralsFlotation behavior of chromite and manganese-bearing minerals has been reviewed. Flotation of these minerals and ores with fatty acids, amines, sulfates, sulfonates and hydroxamates has been presented and is discussed in terms of surface charge and chemical interaction between the mineral surface ...Concentration; Chromite; Deposits1986
72 Miller, Jan D.Gold flotation from Colorado River sand with the air-sparged hydrocyclonePilot-scale tests indicate that effective concentration of fine gold from Colorado River sands can be achieved by flotation with the air-sparged hydrocyclone. The fine sands (55% -kOQ mesh and 0 01 opt *) from gravity concentration were processed with a 5-cm air-sparged hydrocyclone (capacity -1.0 t...Gold; Hydrocyclones; Sand; Flotation1986
73 Miller, Jan D.; Niewiadomski, Marcin M.; Hupka, Jan; Nalaskowski, JakubAir bubble and oil droplet interactions in centrifugal fields during air-sparged hydrocyclone flotationThe interactions of air bubbles and oil droplets in centrifugal flotation have been considered with respect to process conditions present during Air-sparged Hydrocyclone (ASH) flotation. Encounter efficiency of oil droplets with air bubbles has been found to be significantly smaller when compared t...Centrifugal flotation; Froth flotation; Oil flotation; Dispersed oil; Air-sparged hydrocyclone; ASH2007
74 Miller, Jan D.Axial flow reversal and its significance in air-sparged hydrocyclone (ASH) flotationIn recent years the potential of air-sparged hydrocyclone (ASH) flotation for fine coal cleaning has been demonstrated both in pilot plant testing and in a plant-site demonstration program. Further improvements in the ASH technology will depend, to some extent, on improved understanding of the co...Flotation; zero axial velocity; computational fluid dynamics1995
75 Miller, Jan D.Infrared spectroscopy for in-situ characterization of surface reactionsInfrared spectroscopy has been one of the most useful experimental techniques for the analysis of surface reactions in flotation systems, including surface alteration and surfactant adsorption reactions. With the advent of Fourier transform infrared (FTIR) spectrometers, many low-energy throughpu...Reflection; Flotation; Measurements1989
51 - 75 of 152