Geopolitics Of Rare Earth Elements,
2017
Purdue University
Geopolitics Of Rare Earth Elements, Bert Chapman
Libraries Faculty and Staff Presentations
Rare earth elements (REE) contain unique chemical physical properties such as lanthamum, are found in small concentrations, need extensive precise properties to separate, and are critical components of modern technologies such as laser guidance systems, personal electronics such as IPhones, satellites, and military weapons systems as varied as Virginia-class fast attack submarines, DDG-51 Aegis destroyers, the F-35 Joint Strike Fighter, and precision guided munitions. The U.S. has some rare earth resources, but is heavily dependent on access to them from countries as varied as Afghanistan, Bolivia, and China. Losing access to these resources would have significant adverse economic, military, and …
Engineering Decision Making Under Uncertainties,
2017
Michigan Technological University
Engineering Decision Making Under Uncertainties, Snehamoy Chatterjee
TechTalks
Uncertainty is an inherent component of any engineering problem. Uncertainty comes at different stages of an engineering project with different level of complexities. Decision making by neglecting uncertainty may leads to an incorrect solution for a project. Our research focuses on identification and quantification of different sources of uncertainness, and bringing uncertainties within the decision making framework. We are developing algorithms for uncertainty evaluation of spatial and temporal data by integrating multiple source and multiple scale data types, and stochastic optimization models to take into account multiple objectives and constraints. We are applying our research on mining, geology, and geo-hydrology …
Atmospheric Processes Affecting The Separation Of Volcanic Ash And So < Inf> 2 In Volcanic Eruptions: Inferences From The May 2011 Grímsvötn Eruption,
2017
University of Oxford
Atmospheric Processes Affecting The Separation Of Volcanic Ash And So < Inf> 2 In Volcanic Eruptions: Inferences From The May 2011 Grímsvötn Eruption, Fred Prata, Mark Woodhouse, Herbert E. Huppert, Andrew Prata, Thor Thordarson, S. Carn
Michigan Tech Publications, Part 1
The separation of volcanic ash and sulfur dioxide (SO2) gas is sometimes observed during volcanic eruptions. The exact conditions under which separation occurs are not fully understood but the phenomenon is of importance because of the effects volcanic emissions have on aviation, on the environment, and on the earth's radiation balance. The eruption of Grímsvötn, a subglacial volcano under the Vatnajökull glacier in Iceland during 21-28 May 2011 produced one of the most spectacular examples of ash and SO2 separation, which led to errors in the forecasting of ash in the atmosphere over northern Europe. Satellite data from several sources …
Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties,
2017
Norwegian Institute of Air Research
Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties, A. Vogel, S. Diplas, A. J. Durant, A. S. Azar, M. F. Sunding, William I. Rose, A. Sytchkova, C. Bonadonna, K. Krüger, A. Stohl
Department of Geological and Mining Engineering and Sciences Publications
Uncertainty in the physicochemical and optical properties of volcanic ash particles creates errors in the detection and modeling of volcanic ash clouds and in quantification of their potential impacts. In this study, we provide a data set that describes the physicochemical and optical properties of a representative selection of volcanic ash samples from nine different volcanic eruptions covering a wide range of silica contents (50–80 wt % SiO2). We measured and calculated parameters describing the physical (size distribution, complex shape, and dense-rock equivalent mass density), chemical (bulk and surface composition), and optical (complex refractive index from ultraviolet to …
Degradation Of Bisphenol-A By Dielectric Barrier Discharge System: Influence Of Polyethylene Glycol Stabilized Nano Zero Valent Iron Particles,
2017
Missouri University of Science and Technology
Degradation Of Bisphenol-A By Dielectric Barrier Discharge System: Influence Of Polyethylene Glycol Stabilized Nano Zero Valent Iron Particles, Jimoh O. Tijani, Massima E.S. Mouele, Ojo O. Fatoba, Omotola O. Babajide, Leslie F. Petrik
Mining Engineering Faculty Research & Creative Works
In this study we report the synthesis and catalytic properties of polyethylene glycol stabilized nano zero valent iron particles (PEG-nZVI) added to the dielectric barrier discharge (DBD) system to induce photo-Fenton process in the degradation of bisphenol A (BPA) in aqueous solution. The influence of operating parameters such as solution pH, initial concentration of the modelled pollutant and PEG-nZVI dosage on the extent of BPA degradation was investigated. The residual concentration of BPA and its intermediates were determined using high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LCMS). The high-resolution scanning electron microscope (HRSEM), x-ray diffraction (XRD), Brunauer-Emmett-Teller …
Dpm Dispersion Inside A Single Straight Entry Using Dynamic Mesh Model,
2017
Missouri University of Science and Technology
Dpm Dispersion Inside A Single Straight Entry Using Dynamic Mesh Model, Yi Zheng, Ying Li, Magesh Thiruvengadam, Hai Lan, Jerry C. Tien
Mining Engineering Faculty Research & Creative Works
Three-dimensional simulations of diesel particulate matter (DPM) distribution inside a single straight entry for the Load-Haul-Dump loader (LHD)-truck loading and truck hauling operations were conducted by using ANSYS FLUENT computational fluid dynamics software. The loading operation was performed for a fixed period of 3 min. The dynamic mesh technique in FLUENT was used to study the impact of truck motion on DPM distribution. The resultant DPM distributions are presented for the cases when the truck was driving upstream and downstream of the loading face. Interesting phenomena were revealed in the study including the piston effect, layering of DPM in the …
Effects Of Loading Rate On Gas Seepage And Temperature In Coal And Its Potential For Coal-Gas Disaster Early-Warning,
2017
Missouri University of Science and Technology
Effects Of Loading Rate On Gas Seepage And Temperature In Coal And Its Potential For Coal-Gas Disaster Early-Warning, Chong Zhang, Xiaofei Liu, Guang Xu, Xiaoran Wang
Mining Engineering Faculty Research & Creative Works
The seepage velocity and temperature externally manifest the changing structure, gas desorption and energy release that occurs in coal containing gas failure under loading. By using the system of coal containing gas failure under loading, this paper studies the law of seepage velocity and temperature under different loading rates and at 1.0 MPa confining pressure and 0.5 MPa gas pressure, and combined the on-site results of gas pressure and temperature. The results show that the stress directly affects the seepage velocity and temperature of coal containing gas, and the pressure and content of gas have the most sensitivity to mining …
Impact Of Coalbed Incidence Angle On Methane Enrichment Zone In Longwall Gob,
2017
Missouri University of Science and Technology
Impact Of Coalbed Incidence Angle On Methane Enrichment Zone In Longwall Gob, Shengyong Hu, Ao Zhang, Guorui Feng, Shuwen Guan, Xiangqian Guo, Chao Li, Guang Xu
Mining Engineering Faculty Research & Creative Works
To control methane emissions in gob into longwall working faces, it is necessary to understand the distributions of methane enrichment zones (MEZ) around mined coal seams with different incidence angles. In this paper, FLAC3D software is used to calculate the three-dimensional stress distributions in MEZ in gobs with coalbed incidence angles ranging from 0° to 50°. The results show that MEZ consistently exhibit a "hexagon" shape, and rotate in a clockwise direction as the coalbed angle increases. The MEZ range above the mined seam is larger than that below the mined seam. As the coalbed angle increases, the MEZ …
Degradation Of 2-Nitrophenol By Dielectric Barrier Discharge System: The Influence Of Carbon Doped Tio2 Photocatalyst Supported On Stainless Steel Mesh,
2017
Missouri University of Science and Technology
Degradation Of 2-Nitrophenol By Dielectric Barrier Discharge System: The Influence Of Carbon Doped Tio2 Photocatalyst Supported On Stainless Steel Mesh, J. O. Tijani, M. E.S. Mouele, T. C. Tottito, O. O. Fatoba, L. F. Petrik
Mining Engineering Faculty Research & Creative Works
This study investigated the degradation of 2-nitrophenol (2-NP) in aqueous solution by dielectric barrier discharge (DBD) system alone and its combination with supported TiO2 photocatalysts. The TiO2 photocatalyst supported on a stainless-steel mesh was synthesized using sol–gel solution of 8% polyacrylonitrile (PAN)/dimethylformamide/TiCl4 followed by pyrolysis in the furnace under N2 atmosphere at temperatures of 300, 350, or 400 °C for 3 h holding time. The supported catalysts were characterized for their morphologies, functional groups, crystallinity, surface areas and elemental chemical states by high resolution scanning electron microscope (HRSEM), Fourier transform infrared, X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, …
A Novel Applications Of Photogrammetry For Retaining Wall Assessment,
2017
Michigan Technological University
A Novel Applications Of Photogrammetry For Retaining Wall Assessment, Renee Oats, Rudiger Escobar-Wolf, Thomas Oommen
Michigan Tech Publications, Part 1
Retaining walls are critical geotechnical assets and their performance needs to be monitored in accordance to transportation asset management principles. Current practices for retaining wall monitoring consist mostly of qualitative approaches that provide limited engineering information or the methods include traditional geodetic surveying, which may provide high accuracy and reliability, but is costly and time-consuming. This study focuses on evaluating failure modes of a 2.43 m × 2.43 m retaining wall model using three-dimensional (3D) photogrammetry as a cost-effective quantitative alternative for retaining wall monitoring. As a remote sensing technique, photogrammetry integrates images collected from a camera and creates a …
Recovery Of Phosphate Minerals From Plant Tailings Using Direct Froth Flotation,
2017
Missouri University of Science and Technology
Recovery Of Phosphate Minerals From Plant Tailings Using Direct Froth Flotation, Ashraf Alsafasfeh, Lana Z. Alagha
Mining Engineering Faculty Research & Creative Works
Wastes produced from the phosphate industry presents many challenges due to the high economic and environmental impacts involved with their disposal. However, the relative scarcity of high-grade phosphate ores has driven researchers to recover and recycle these valuable wastes (secondary sources). The goal of this study was to investigate the possibility of upgrading the P2O5 content in tailings produced from a phosphorous production plant using direct froth flotation. Characterization assays, including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), and mineral liberation analysis (MLA), were first conducted to identify the mineralogical and morphological characteristics of …
Expanding Understanding Of Optical Variability In Lake Superior With A 4-Year Dataset,
2017
Michigan Technological University
Expanding Understanding Of Optical Variability In Lake Superior With A 4-Year Dataset, Colleen B. Mouw, Audrey B. Ciochetto, Brice Grunert, Angela W. Yu
Michigan Tech Publications, Part 1
Lake Superior is one of the largest freshwater lakes on our planet, but few optical observations have been made to allow for the development and validation of visible spectral satellite remote sensing products. The dataset described here focuses on coincidently observing inherent and apparent optical properties along with biogeochemical parameters. Specifically, we observe remote sensing reflectance, absorption, scattering, backscattering, attenuation, chlorophyll concentration, and suspended particulate matter over the ice-free months of 2013-2016. The dataset substantially increases the optical knowledge of the lake. In addition to visible spectral satellite algorithm development, the dataset is valuable for characterizing the variable light field, …
The Effect Of Conditioning On The Flotation Of Pyrrhotite In The Presence Of Chlorite,
2017
Central South University, China
The Effect Of Conditioning On The Flotation Of Pyrrhotite In The Presence Of Chlorite, Yanfei Chen, Qing Shi, Qimeng Feng, Yiping Lu, Wencai Zhang
Mining Engineering Faculty Publications
The influence of conditioning on the flotation of pyrrhotite in the presence of chlorite was investigated through flotation tests, sedimentation tests, and X-ray photoelectron spectroscopy (XPS) analysis. The flotation results show that chlorite slimes dramatically impair the flotation of pyrrhotite. Sedimentation and flotation tests reveal that conditioning can effectively remove chlorite slimes from pyrrhotite surfaces, resulting in an enhanced flotation recovery of pyrrhotite. When mixed minerals were conditioned under the natural atmosphere, a faster conditioning speed and longer conditioning time decreased the flotation recovery of pyrrhotite. However, when mixed minerals were conditioned under a nitrogen atmosphere, a more intensive conditioning …
Comparing Distributed Acoustic Sensing To Three-Component Geophones In An Underground Mine,
2017
Montana Tech
Comparing Distributed Acoustic Sensing To Three-Component Geophones In An Underground Mine, Nikolas Nesladek
Graduate Theses & Non-Theses
Geophones have become the industry standard for seismic data collection. However, a relatively new method is gaining popularity called Distributed Acoustic Sensing (DAS). DAS uses changes in backscattered light of a fiber-optic cable to detect strain from acoustic energy. The purpose of this project was to make a direct comparison between DAS and three component geophones, specifically in a mining setting. Experiments were done in the Underground Education Mining Center on the campus of Montana Tech. The sources used for this project were vertical sledgehammer shots, oriented shear sledgehammer shots, and blasting caps set off in both unstemmed and stemmed …
Synthesis, Characterization And Photocatalytic Activity Of Ag Metallic Particles Deposited Carbon-Doped Tio2 Nanocomposites Supported On Stainless Steel Mesh,
2017
Missouri University of Science and Technology
Synthesis, Characterization And Photocatalytic Activity Of Ag Metallic Particles Deposited Carbon-Doped Tio2 Nanocomposites Supported On Stainless Steel Mesh, J. O. Tijani, T. C. Totito, O. O. Fatoba, O. O. Babajide, L. F. Petrik
Mining Engineering Faculty Research & Creative Works
Abstract: In this present work, post deposition of metallic Ag nanoparticles on carbon-doped TiO2 nanocomposites supported on stainless steel mesh was achieved via a combination of sol–gel and thermal evaporation techniques. Poly acrylonitrile dissolved in dimethyl formamide, and titanium tetra chloride was used as a carbon and titanium precursor, respectively. The photocatalytic activity of the prepared supported catalysts was evaluated by the degradation of an aqueous solution of methylene blue as a model pollutant under ultra-violet light irradiation. The prepared photocatalysts were characterized by several analytical techniques such as high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, Brunauer–Emmett–Teller …
Spatial Variability Of Co < Inf> 2 Uptake In Polygonal Tundra: Assessing Low-Frequency Disturbances In Eddy Covariance Flux Estimates,
2017
Institutionen för Naturgeografi och Ekosystemvetenskap, Lunds Universitet
Spatial Variability Of Co < Inf> 2 Uptake In Polygonal Tundra: Assessing Low-Frequency Disturbances In Eddy Covariance Flux Estimates, Norbert Pirk, Jakob Sievers, Jordan Mertes, Frans Jan W. Parmentier, Mikhail Mastepanov, Torben R. Christensen
Michigan Tech Publications, Part 1
The large spatial variability in Arctic tundra complicates the representative assessment of CO2 budgets. Accurate measurements of these heterogeneous landscapes are, however, essential to understanding their vulnerability to climate change. We surveyed a polygonal tundra lowland on Svalbard with an unmanned aerial vehicle (UAV) that mapped ice-wedge morphology to complement eddy covariance (EC) flux measurements of CO2. The analysis of spectral distributions showed that conventional EC methods do not accurately capture the turbulent CO2 exchange with a spatially heterogeneous surface that typically features small flux magnitudes. Nonlocal (low-frequency) flux contributions were especially pronounced during snowmelt and introduced a large bias …
Responsiveness Of Mining Community Acceptance Model To Key Parameter Changes,
2017
Missouri University of Science and Technology
Responsiveness Of Mining Community Acceptance Model To Key Parameter Changes, Mark Kofi Boateng, Kwame Awuah-Offei
Mining Engineering Faculty Research & Creative Works
The mining industry has difficulties predicting changes in the level of community acceptance of its projects over time. These changes are due to changes in the society and individual perceptions around these mines as a result of the mines' environmental and social impacts. Agent-based modeling can be used to facilitate better understanding of how community acceptance changes with changing mine environmental impacts. This work investigates the sensitivity of an agent-based model (ABM) for predicting changes in community acceptance of a mining project due to information diffusion to key input parameters. Specifically, this study investigates the responsiveness of the ABM to …
Surface-Modified Polyacrylonitrile Nanofibres As Supports,
2017
Missouri University of Science and Technology
Surface-Modified Polyacrylonitrile Nanofibres As Supports, Chris Ademola Bode-Aluko, Omoniyi Pereao, Olanrewaju Fatoba, Leslie Petrik
Mining Engineering Faculty Research & Creative Works
Polyacrylonitrile nanofibers (PAN-nfs) are one of the most studied nanofibers because of their excellent characteristics, such as good mechanical strength, chemical resistance, and good thermal stability. Due to the easy dissolution in polar organic solvents, PAN-nfs are mostly produced via electrospinning technique. The electro spun PAN-nfs surfaces are relatively in-active and hydrophobic, and, therefore, hinder some potential applications; however, chemical surface modification reactions, such as amination, reduction, hydrolysis, and amidoximation, have been carried out on them. These reactions bring about functional groups, such as amine, hydroxyl, carboxylic, imine etc., to the surface PAN-nfs and invariably make their surfaces active and …
Flotation Behavior Of Complex Sulfide Ores In The Presence Of Biodegradable Polymeric Depressants,
2017
Missouri University of Science and Technology
Flotation Behavior Of Complex Sulfide Ores In The Presence Of Biodegradable Polymeric Depressants, Muhammad Badar Hayat, Lana Z. Alagha, Syed Mohammad Sannan
Mining Engineering Faculty Research & Creative Works
In this study, chitosan polymer was tested as a potential selective green depressant of pyrite in the bulk flotation of galena (PbS) and chalcopyrite (CuFeS2) from sphalerite (ZnS) and pyrite (FeS2) using sodium isopropyl xanthate as a collector and 4-methyl-2-pentanol (MIBC) as a frother. Flotation tests were carried out in a D12-Denver flotation laboratory cell in the presence and absence of chitosan and/or sodium cyanide depressant which is commercially used as pyrite depressant in sulfide mineral flotation process. Flotation recoveries and concentrate grades (assay) were studied as a function of polymer concentration and flotation time. It …
Effect Of Single Dead End Entry Inclination On Dpm Plume Dispersion,
2017
Missouri University of Science and Technology
Effect Of Single Dead End Entry Inclination On Dpm Plume Dispersion, Yi Zheng, Hai Lan, Magesh Thiruvengadam, Jerry C. Tien, Ying Li
Mining Engineering Faculty Research & Creative Works
Diesel particulate matter (DPM) is a by-product from operating diesel engines. Since diesel powers are one of the major sources of energy for mobile underground mining equipment, the adverse health effects of DPM are of a great concern. This paper used computational fluid dynamics (CFD) method to study the effect of entry inclination on DPM plume distribution in a dead-end entry. An upward mining face and a downward mining face were built with a truck and a loader in loading operation close to the face area. A species transport model with incorporated buoyancy effect was used to examine the DPM …
