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Showing 1 to 20 of 33 for “"Coarse particles"”.
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Chemistry of airborne particles from metallurgical processing
Airborne particles fall into one of three size ranges. The nucleation range consists of nanoparticles created from vapor atom collisions. The decisive parameter for particle size and composition is the supercooling of the vapor. The accumulation range, which comprises particles less than 2 …
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The effect of energy input on flotation kinetics
… to an increase in the flotation rate for fine particles, an optimum flotation rate for intermediate particles and a decrease in the flotation rate for coarse particles. The optimum in the flotation rate for minerals with higher density is at a lower energy input than that for lower density …
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An experimental study of solid propellant deflagration using high speed motion pictures and postfire residue analysis
… in all cases while the mean diameters of the coarse particles was approximately the same size as the initial aluminum cast in the propellant. Measurements taken from the high speed motion pictures included resolution, propellant burning rate, the diameter of burning particles ejected from the …
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A mathematical model for predicting classification performance in wet fine screens
… The process involves separation of fine particles from coarse particles based on size and is applicable to both dry and fine screening. Fine screening is normally carried out wet. Until recently, fine wet screening had been limited to relatively low throughput applications. Developments …
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Effect of particle size on slugging fluidised beds
… fluidising fluid in all cases was air and the particles used were sand, quartz, ballotini and catalyst. The range of particle sizes was about 30 to 500 microns. Column diameters of 1 to 4 inches were used. Much of the work is concerned with the varying behaviour of slugs in beds of different …
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Pipeline flow of coarse particle slurries
The horizontal pipeline flow of coarse-particle slurries has been examined. The study includes an evaluation of previous work, an experimental investigation and a presentation of improved modelling techniques for determining pipeline design parameters. The experimental investigation was carried out …
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Evaluation of stormwater control measures for the removal and fate of legacy and emerging contaminants
… size fractions including clay, fine silt, coarse silt, and sand. PFAS were evaluated in both dissolved form and associated with total particulates. Stormwater samples were collected at both the inlets and outlets of each SCM during multiple storm events. Results for legacy contaminants …
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THE CHARACTERIZATION AND UTILIZATION OF BARK AS A FLORICULTURE GROWING MEDIUM
… and 75 percent of the total mixture by volume. Coarse particles in both the fresh hardwood and softwood mixtures created greater aeration and drainage than comparable products. Vermiculite was the best overall inorganic component throughout the experiments.</p><p>When properly watered and …
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An investigation of particle collection efficiency in different particle-bubble contacting environments in flotation
The collection efficiency of quartz particles in four different particle-bubble contacting environments was investigated during this thesis. Flotation experiments were carried out in a hybrid flotation column that could be modified into three different cell configurations (a quiescent column cell, …
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Sulphur sorbent particle effects in fluidised combustion
… African sorbents. The sulphation of sorbent particles is described by a simple, two-parameter, kinetic model. No loss in physical relevance is incurred when the decrease in reaction rate with time is given by a negative exponential term. Both sulphation rate and capacity are shown to be …
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Hydrodynamics, stability and scale-up of slot-rectangular spouted beds
… in gas/particle processes such as drying of coarse particles and coating of tablets. However, application of this spouted bed was limited because of instability and insufficient hydrodynamic studies. The present work is therefore aimed at the study of hydrodynamics, stability and scale-up of …
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Heterogeneous combustion of condensed particles in transition regime
… are performed for combustion of zirconium particles of different sizes. Temperature and oxygen concentration profiles are calculated and compared to those predicted by the continuous medium transfer model. It is shown that for particles in the range from 100 nm up to 30 gm heat and mass …
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Investigation of the effect of particle size on froth stability
… in the physico-chemical properties of liberated particles, mainly the particle hydrophobicity which allows the particles to be attached to air bubbles rising from the pulp phase into the froth phase and subsequently collected to the launder. The stability of the froth phase which is be defined as …
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Hydrodynamics and heat transfer in shallow fluidized beds
… terms of fluidization variables. For relatively coarse particles (Geldart's Group B particles) the vigor of solid mixing can be the most important factor in affecting the heat-transfer performance. Bed voidage and static electricity effects are found to be important for smaller and/or lighter …
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Interactions Between Dust and Ecosystem, and Landscape at Multiple Scales
… Africa. Findings indicate that the fraction of coarse dust in emissions increases with wind speed and slope, particularly under uphill winds, the latter highlighting the role of topography in enhancing vertical transport for larger particles. These positive correlations weaken during the …
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Developing analytical methods to determine physicochemical properties, protein and amino acid composition of African staple foods
… diffraction which showed corn-soya and teff had coarse particles distributed within a similar size fraction. Maize, cassava and sorghum showed relatively fine particles distributed between multiple size fractions. The protein and amino acid composition was also determined to evaluate the …
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Mass, Composition, Source Identification and Impact Assessment for Fine and Coarse Atmospheric Particles in the Desert Southwest
… Pinal County, Arizona to characterize fine and coarse particulate matter as a means of furthering our understanding of ambient concentrations and composition in rural, arid environments. Detailed measurement of ambient fine and coarse mass, ion, metal, and carbon concentrations at one-in-six day …
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Bubble Size Effects in Coal Flotation and Phosphate Reverse Flotation using a Pico-nano Bubble Generator
… that the low-flotation efficiency of ultrafine particles is mainly due to the low probability of bubble-particle collision while the main reason for poor flotation recovery of coarse particles is the high probability of detachment of particles from the bubble surface.;Pico-nano bubbles refer to …
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Burn time measurements of micron sized Al-Mg alloys and Mg in a heterogeneous shock tube in different oxidizing environments
… on Mg and Mg-Al alloys has been performed with coarse particles (>50 μm), which tend to have burn times in the 1-100 milliseconds. Work on single aluminum particles below 10 microns has shown a transitional regime. This marks the shift from diffusion limited combustion to the kinetically limited …
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Scale-up of Using Novel Dewatering Aids
… removal of free water from the surface of fine particles is difficult and costly, and often the results are less than desirable. Fine particles inherently have very large surface areas, and hence retain large amounts of water. Increased amounts of fines also cause denser particle packing, which …
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