Dissertations / Theses: 'Sea Mine'

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Wolfson, Monica L. "Multibeam Observations of Mine Scour and Burial near Clearwater, Florida, Including a Test of the VIMS 2D Mine Burial Model." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001197.

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2

Cintron, Carlos J. "Environmental impact on mine hunting in the Yellow Sea using the CASS /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA390451.

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3

Arby, Nathaniel. "Hur utvecklas den svenska minröjningsfunktionen inom marinen?" Thesis, Swedish National Defence College, Swedish National Defence College, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-18.

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Sjöminan har sänkt och skadat mer tonnage än alla andra vapensystem till sjöss. Då medel föder motmedel har sjöminan och minröjningen följt varandra i en lång duell.

Huvudsyftet med denna uppsats är att undersöka hur de svenska minröjningsförbanden utvecklas inom taktik och teknik och hur dessa komponenter förhåller sig till varandra. Uppsatsen söker även svaret på hur utvecklingen från minröjningsklass Landsort till minröjningsklass Koster skett.

Med hjälp av deskriptiv metod kommer Militärstrategisk doktrin, Doktrin för marina operationer samt Försvarsmaktens läroböcker i Mineringstjänst, Minmotmedelstjänst och Minröjningstjänst att användas för att redogöra hur den marina taktiken och tekniken utvecklas som ett medel i duellen mot sjöminan.

De svenska minröjningsfartygens taktiska och tekniska utveckling grundar sig på de militära basfunktionerna, ledning, verkan, skydd, rörelse, underrättelse samt uthållighet. Samtidigt utvecklas minröjningsförbanden i Försvarsmakten mot ett, både för personal och materiel, säkrare och effektivare förband.

The main purpose with this essay is to examine the development of the Swedish mine warfare branch both tactical and technical and how these two components are combined to maximize the effect. The essay also analyses the midlife upgrade of the MCMV Landsort class towards the MCMV Koster class.

This essay will describe on the basis of the Swedish doctrines and mine warfare textbooks how the naval tactics and technology function as a foundation for development of new means in the duel against the sea mine.

The sea mine is a weapon system that has been used during several centuries and has sunk more tonnage than all other weapon systems together. As long as there have been sea mines, there has also existed its counterpart, the mine counter measures.

The Swedish MCMV’s technological and tactical developments strive towards fulfilling the six mandatory functions in warfare, command, effect, protection, mobility, intelligence and endurance. The modern MCMV develops toward a more secure and efficient unit.

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4

Hsieh, Chung-Ping. "Effect of internal solitary waves on mine detection in the western Philippine Sea east of Taiwan." Thesis, Monterey, Calif. : Naval Postgraduate School, 2006. http://bosun.nps.edu/uhtbin/hyperion.exe/06Dec%5FHsieh.pdf.

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Thesis (M.S. in Phycsical [Physical] Oceanography)--Naval Postgraduate School, December 2006.
Thesis Advisor(s): Peter C. Chu. "December 2006." Includes bibliographical references (p.115-117). Also available in print.

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5

Bynoe, Rachel. "The Great Fossil Mine of the southern North Sea : exploring the potential of submerged Palaeolithic archaeology." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/366437/.

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This research explores the potential of the submerged Palaeolithic archaeology of the southern North Sea for answering questions about how hominins occupied and adapted within their environments in these northerly latitudes throughout the Pleistocene. Recent coastal discoveries in East Anglia have demonstrated occupation as far back as ~1 million years, and yet our appreciation of the how, why and who of this occupation is missing a crucial piece of its puzzle; excluding these now-submerged landscapes is an active bias on our understanding, truncating the archaeological record. Having been subjected to repeated glaciations, trans- and regressions, the very processes that led to the terrestrial exposure of these areas have subsequently led to their neglect: the assumption that pre-LGM deposits will have been eroded or re-worked has prevailed. Recent work, however, has demonstrated the inaccuracy of this assumption, with evidence for extant Pleistocene-age deposits, landscape features and archaeology. Unlocking the clear potential of these submerged landscapes now relies on the approaches that we take to their investigation as, to-date, all archaeological finds have been entirely by chance. In order to move beyond this reactive style of archaeology, methodologies must be developed which tackle these areas in a more focused and reasoned way. The research undertaken throughout this PhD makes steps towards this. Starting from no baseline understanding of the nature of the existing resource, this work located, collated and analysed a prolific collection of 1,019 faunal specimens. Recovered by the 19th and 20th Century UK trawling industry, the development of historical methods has elucidated their locations and conditions of collection. Combining this locational information with species taxonomic evolution, the emergent spatio-temporal patterns provide a fresh understanding of the integrity of the extant deposits and unique opportunities for locating them on the seabed. These results are presented at a range of scales: • First, a broad-scale understanding of offshore regions across the southern North Sea which have demonstrated a dominance of cold-stage species from MIS 8-MIS 2. • Secondly, a local scale: linking faunal remains with seabed features in the near shore area off Happisburgh, identifying Early and early Middle Pleistocene assemblages related to exposures of the CFbF. • Finally, a discrete, high resolution area of seabed off the coast of Clacton has been identified. Through the collection of swath bathymetry, this area has shown the exciting correlation of Pleistocene seabed deposits and faunal remains. This research presents a significant move towards a proactive approach to these submerged landscapes and represents a step-change in our ability to understand, locate and engage with this undervalued archaeological resource.

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Starling, Antony. "Tectonic and chemical evolution of a late Proterozoic gold deposit, Gebeit Mine, Northern Red Sea Hills, Sudan." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358662.

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7

Thies, Jane E. "Mapping of hydrogeology of underground mines in the Upper Freeport coal seam, northern Appalachian Basin, WV-PA-MD." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5439.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains x, 86, [22] p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 58-63).

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Moschovos, Ioannis S. "Compare at sea position using Mini-Ranger." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/25748.

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Coke, Hartwell F. "Route survey periodicity for mine warfare." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep_Coke.pdf.

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Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, September 2009.
Thesis Advisor(s): Chu, Peter. "September 2009." Description based on title screen as viewed on November 5, 2009. Author(s) subject terms: Mine Warfare, periodicity, route survey, oceanographic, key parameters, resurvey integration model, survey model. Includes bibliographical references (p. 55-56). Also available in print.

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Akram, Muhammad. "Stability assessment of entry roofs in underlying multiple seam mines." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-171333/.

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Meyer, Petrus C. "Feasibility of thin seam coal mining at Dorstfontein Coal Mine." Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-09072005-113231/.

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12

Meyer, Petrus Cornelius. "Feasibility of thin seam coal mining at Dorstfontein Coal Mine." Diss., University of Pretoria, 2003. http://hdl.handle.net/2263/27806.

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13

Xie, Chen. "Characterization of coupled body response in random sea." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4871.

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The frequent use of two or more closely positioned vessels during offshore operations makes the study of multi-body hydrodynamics an important topic, especially for the design of deepwater offshore systems. This research investigation studies the response behavior of a coupled mini-TLP / barge system in both head and beam sea conditions. The design sea conditions were selected to represent the combined wind, wave and current conditions for a target location off the coast of West Africa. Both the mini-TLP and the barge were designed to have independent mooring systems. Coupling between the two vessels is introduced through a connection consisting of two breast lines and a fender system. This connection is designed to restrain the horizontal movements of the two vessels while keeping a constant distance between them and avoiding collisions. The main focus of this study is to analyze the experimental data obtained during the model testing, especially the motions of the two bodies and the values related to the fender system, in order to characterize the behavior of the uncoupled and coupled system configurations. A statistical approach is used for the data analysis and interpretation. Statistical parameters are used to provide an overall characterization of system behavior, and Gaussian and Weibull distribution functions are utilized to detect the importance of non-linearity in the data with particular attention to extreme values. Correlations between the two vessels in time domain and frequency domain are investigated. In addition, auto and cross spectrum analyses of the data are used to contrast the motion behavior of the uncoupled and coupled configurations. It is shown that the connection system reduces the horizontal vessel motions; however the forces exerted on the fender system show significant variation depending on sea heading conditions.

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Wheatley, Nicola S. "Determining route survey periodicity for mine warfare investigation of bedforms, waves, tides and currents." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep%5FWheatley.pdf.

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Thesis (M.S. in Physical Oceanography)--Naval Postgraduate School, September 2009.
Thesis Advisor(s): Chu, Peter. "September 2009." Description based on title screen as viewed on November 5, 2009. Author(s) subject terms: Mine Warfare, Route Survey, Bedforms, Waves, Tides, Currents, Survey Periodicity, Sediment Transport, Sediment Dynamics, Bathymetry, GIS, Weighted Suitability Model, San Francisco Bay. Includes bibliographical references (p. 99-102). Also available in print.

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15

Holmbom, Joakim. "Modelling of Waves and Currents in the Baltic Sea." Thesis, KTH, Vattendragsteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96232.

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To facilitate the process of setting up small scale environmental models in coastal and offshore areas a wave model and a 2D current model for the Baltic Sea have been set up with MIKE 21. The ambition is that the Baltic Sea model can serve as a source of boundary conditions for local models. The main focus in the project has been to determine which input data to use to get the best results and then to calibrate and validate the model with the best data sets available. The wave model has been tested with three different sources of wind forcing and the results with the different sources are evaluated. The wave model has been calibrated and validated against five wave buoys and the current model against three current observation stations. The comparison shows that the wave model gives good estimations of wave height, period and direction. The output of the current model coincides with observations where distinct current patterns exist. The wave model is considered a good source to extract wave statistics from for the entire Baltic Sea. The current model can be used for scenarios or areas that do not suffer from the limitations of a 2D model.

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16

Sellami, Moncef. "Recoverable reserve estimation in multiple seam mines." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09192009-040606/.

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17

Ganguli, Rajive. "Stress transfer between multi-seam longwall mines." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-03242009-040935/.

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18

Luo, JunLu. "Gateroad Design in Overlying Multi-Seam Mines." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36553.

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There are two major design problems for upper seam longwall gateroads operating in a multi-seam environment. The first is to determine the location, magnitude and duration of stress transferred from lower seam mines; and the second is to predict the effect of stress transferred from lower seam mines on opening stability. To solve these problems for both longwall and room-and-pillar mines, case study data were collected and analyzed to develop empirical models predicting upper seam damage created by mining activities in the lower seam. Analysis showed vertical movement in the upper seam and roof CMRR (Coal Mine Roof Rating) to be the controlling factors in damage prediction and, therefore, gateroad planning and design. The relationship between the predicted damage rating and the gateroad stability was established and quantified. To simplify the application of design procedures developed for longwall gateroad systems, the criteria were incorporated in a Windows-based, multi-interface software , UGLY (Upperseam Gateroad Longwall Stability). The programming language was Visual Basic, and the program's design capabilities were validated and demonstrated using case study data.
Master of Science

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19

Rudisell, Michael T. "Evaluation of the Broken Aro flue-gas desulfurization sludge mine seal project to abate acid mine drainage located in coshocton county, Ohio." Ohio University / OhioLINK, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1175630479.

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20

Thomas, Jed H. "Evaluation of the flue gas desulfurization mine seal and sedimentation pond at Broken Aro Mine Reclamation Site located in Coshocton County, Ohio." Ohio University / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1177443117.

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21

Johann, Victoria Anne. "Development and Implementation of an Automated SEM-EDX Routine for Characterizing Respirable Coal Mine Dust." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/73367.

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This thesis describes the development and use of a computer-automated microscopy routine for characterization of respirable dust particles from coal mines. Respirable dust in underground coal mining environments has long been known to pose an occupational health hazard for miners. Typically following years of exposure, coal workers' pneumoconiosis (CWP) and silicosis are the most common disease diagnoses. Although dramatic reductions in CWP and silicosis cases were achieved across the US between about 1970-1999 through a combination of regulatory dust exposure limits, improved ventilation and dust abatement practices, a resurgence in disease incidence has been noted more recently – particularly in parts of Appalachia. To shed light on this alarming trend and allow for better understanding of the role of respirable dust in development of disease, more must be learned about the specific characteristics of dust particles and occupational exposures. This work first sought to develop an automated routine for the characterization of respirable dust using scanning electron microscopy with energy dispersive x-ray (SEM-EDX). SEM-EDX is a powerful tool that allows determination of the size, shape, and chemistry of individual particles, but manual operation of the instrument is very time consuming and has the potential to introduce user bias. The automated method developed here provides for much more efficient analysis – with a data capture rate that is typically 25 times faster than that of the manual method on which it was based – and also eliminates bias between users. Moreover, due to its efficiency and broader coverage of a dust sample, it allows for characterization of a larger and more representative number of particles per sample. The routine was verified using respirable dust samples generated from known materials commonly observed in underground coal mines in the central Appalachian region, as well as field samples collected in this region. This effort demonstrated that particles between about 1-9μm were accurately classified with respect to defined chemical categories, and suggested that analysis of 500 particles across a large area of a sample filter generally provides representative results. The automated SEM-EDX routine was then used to characterize a total of 210 respirable dust samples collected in eight Appalachian coal mines. The mines were located in three distinct regions (i.e., northern, mid-central and south-central Appalachia), which differed in terms of primary mining method, coal seam thickness and mining height, and coal and/or rock mineralogy. Results were analyzed to determine whether number distributions of particle size, aspect ratio, and chemistry classification vary between and within distinct mine regions, and by general sampling location categories (i.e., intake, feeder, production, return). Key findings include: 1) Northern Appalachian mines have relatively higher fractions of coal, carbonate, and heavy mineral particles than the two central Appalachian regions, whereas central Appalachian mines have higher fractions of quartz and alumino-silicate particles. 2) Central Appalachian mines tended to have more mine-to-mine variations in size, shape, and chemistry distributions than northern Appalachian mines. 3) With respect to particle size, samples collected in locations in the production and return categories have the highest percentages of very small particles (i.e., 0.94-2.0μm), followed by the feeder and then the intake locations. 4) With respect to particle shape, samples collected in locations in the production and return categories have higher fractions of particles with moderate (i.e., length is 1.5 to 3x width) to relatively high aspect ratios (i.e., length is greater than 3x width) compared to feeder and intake samples. 5) Samples with relatively high fractions of alumino-silicates have higher fractions of particles with moderate aspect ratios than samples with low alumino-silicate fractions. 6) Samples with relatively high fractions of quartz particles have higher fractions of particles with moderate aspect ratios and higher percentages of very small particles than samples with no identified quartz particles. 7) Samples with high fractions of carbonates have higher percentages of particles with relatively low aspect ratios (i.e., length and width are similar) than samples with no identified carbonate particles.
Master of Science

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22

Mazouni, Khallil. "Analyse de la photo régulation des gènes secA et fedl chez la cyanobactérie Synechocystis : analyse de la cytokinèse chez la cyanobactérie Synechocystis." Paris 6, 2003. http://www.theses.fr/2003PA066213.

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23

Yancey, Daniel Jackson. "Analysis and Application of Coal Seam Seismic Waves for detection of Abandoned Mines." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/32700.

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It is not uncommon for underground coal mining to be conducted in the proximity of abandoned underground mines that are prone to accumulate water, methane or other toxic gases, and are often either poorly mapped or without good surface survey control. Mining into such abandoned voids poses a great safety risk to personnel, equipment, and production from inundation or toxic/explosive gas release. Often, surface or underground drilling is employed to detect the mine void and evaluate the hazards, sometimes with disastrous results. The use of guided waves within coal seams can be utilized to locate voids, faults, and abrupt seam thickness changes. The use of seam waves for void detection and mine planning has tremendous value and use.

To demonstrate the feasibility of abandoned mine void detection utilizing coal seam seismic waves, two in-seam reflection surveys and a transmission survey were acquired at an abandoned underground mine near Hurley, Virginia. Numerical modeling of the seam waves was examined as well. The Airy phase was observed in the synthetic and real field data. Dispersion analysis of the field data shows reasonable agreement with the dispersion characteristics of the synthetic data. Using standard commonly available seismic reflection processing tools, a known and well-mapped mine was detected and located.

Detection of the mine with both surveys indicates that ``exploratory'' drilling can be replaced by noninvasive seismic methods. Location, however, was not good enough to replace drilling entirely. Hence seismic methods can be used for detection, but if a potential void is detected, focused drilling should be applied for accurate mapping and circumvention of potentially hazardous areas.
Master of Science

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24

Machumele, Nkateko Jones. "A geological, petrological and mineralogical study of the UG3 chromitite seam at Modikwa Platinum Mine : significance to exploration and PGE resources." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1013553.

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The UG3 at Modikwa Platinum Mine occurs as a platiniferous, planar chromitite seam. It is stratigraphically located in the Upper Critical Zone of the Eastern Bushveld Complex. Field work study comprise of underground mapping, sampling, surface mapping, borehole core logging, microprobing and microscopic investigations carried out at the Rhodes University. The UG3 at the Modikwa Platinum Mine is about 22cm thick chromitite seam underlain by a white fine grained anorthosite and overlain by a brown medium grained feldspathic pyroxenite. It is an incomplete cyclic unit consisting of chromite and feldspathic pyroxenite. The UG3 reef at the Modikwa Platinum Mine lease area represents a Platinum Group Metal resource of 300 million tons of ore at an in situ grade of 2.5g/t. Under the current market conditions the UG3 reef remains unprofitable to mine in an underground operation due to the operational cost involved. However, it has been illustrated that the UG3 chromitite seam can increase profit margins in an open pit operation provided it is mined together with the economic UG2 chromitite seam. The extraction of the UG3 as ore in the four Modikwa UG2 open pits would result in a combined operating cash profit of R330 million. The UG3 chromitite seam is platiniferous. The platinum-group minerals (PGM) range in size from less than 10μm to about 70μm. The PGMs are associated with sulphides and are both located in the interstitial silicates and are concentrated in the chromitite seam. The PGMs show a strong preference to contact boundaries of the silicate grains, the chromite grains and the sulphide phases. In some instances, they are enclosed within the chromite grains in association with sulphides. The general sulphide assemblage comprises pentlandite and chalcopyrite whereas, the PGMs assemblage comprises cooperite, ferroplatinum, laurite, FeRhS and PtRhS.

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Jones, Isaiah F. "Monkey see, monkey do, monkey mind-read: On the ability of embodiment to facilitate theory of mind judgments." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1375099367.

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26

Parsons, L. S. "An evaluation of the Canadian 200-mile fisheries zone : benefits,problems and constraints." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70265.

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This thesis evaluates the impact of the Canadian 200-mile fisheries zone from biological, economic and social perspectives. The factors and events leading to the 200-mile zone are examined. The Canadian management regime post-extension is described. Canada derived significant benefits from the 200-mile zone including increased management authority over a vast area with major fish resources, the displacement of foreign fisheries, the development of Canadian fisheries in areas and for species not previously utilized by Canada, and the opportunity to rebuild overfished fish stocks. However, various problems and constraints have led to continued fisheries instability. These include: (1) Natural resource variability, (2) The common property nature of the resource and resultant overcapacity, (3) Fluctuations in market conditions, (4) Heavy dependence on the fisheries in isolated coastal communities, and (5) Recurrent conflict among competing users and conflicting objectives for fisheries management.
Despite Canada's abundant marine fishery resources, various combinations of these factors have contributed to a recurrent boom-and-bust pattern in many marine fisheries. Extended jurisdiction did not provide a panacea for the problems of the fisheries sector. Continued periodic fluctuations in Canada's marine fisheries and demands for government assistance can be expected unless viable alternative economic opportunities can be developed in the coastal regions.

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27

Andoh, Charles. "Business-financed employee voyager-mile points earned from SAA a taxable benefit? /." Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-11122008-180830/.

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28

Agioutanti, Eleftheria. "An Improved Thermogravimetric Analysis Method for Respirable Coal Mine Dust and Comparison to Results by SEM-EDX." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/91984.

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It has long been known that chronic exposures to high concentrations of respirable coal mine dust can lead to the development of lung diseases such as Coal Worker's Pneumoconiosis, commonly referred to as "black lung", and silicosis. Since the mid-1990s, an alarming resurgence of diseases has been documented in central Appalachia, where underground mining often necessitates significant extraction of rock strata along with the thin seams of coal. These circumstances have prompted concern over if or how changing dust composition might be a factor in contemporary disease prevalence. Until now, the total mass concentration and quartz mass fraction of respirable dust have been regulated and monitored in US coal mines. Unfortunately, however, these two metrics alone do not paint a full picture of dust composition. Earlier work in the author's research group established a preliminary thermogravimetric analysis (TGA) method for coal mine dust. The method is intended to allow estimation of three key mass fractions of the dust from separate sources: coal from the coal strata being mined; non-carbonate minerals from the rock strata being mined or drilled; and carbonates that are primarly sourced from application of rock dust products to the mine floor or ribs. However, accuracy of the preliminary method was substantially limited by poor dust recovery from the fibrous filter media used for sample collection. This thesis includes two studies: The first study aims to establish an improved TGA method. It uses smooth polycarbonate (PC) filters for dust sampling and a modified thermal ramping routine. The method is verified using laboratory-generated respirable dust samples. In the second study, the improved TGA method is used to analyze 75 respirable mine dust samples, collected in 15 US mines. Replicate samples are also analyzed by scanning electron microscopy using energy dispersive X-ray (SEM-EDX). TGA and SEM-EDX results are compared to gain insights regarding the analytical methods and general trends in dust composition within and between mines.
Master of Science
It has long been known that chronic exposures to excessive respirable coal mine dust can lead to the development of lung diseases such as Coal Worker’s Pneumoconiosis (“Black Lung”) and silicosis. Disease rates in central Appalachia have shown an alarming and unexpected increase since the mid-1990s, despite declining dust concentrations evident from regulatory compliance monitoring data. Clearly, there is a need to better understand coal mine dust composition, which will require additional analytical methods. Thermogravimetric analysis (TGA) has been proposed as one possible method, because it should allow estimation of three key dust components from separate sources: coal from the coal strata being mined; non-carbonate minerals from the rock strata being mined or drilled; and carbonates from application of rock dust products to the mine floor and ribs. However, preliminary work with TGA showed limited accuracy, mostly due to sampling materials. In this thesis, two studies were performed. The first study aims to establish an improved TGA method using smooth, polycarbonate (PC) filters. The second study demonstrates the method on a large number of mine dust samples, and compares the results to those gained by an alternative method that uses electron microscopy.

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Basu, Kohinoor. "Feasibility of an Integrated Thin Seam Coal Mining and Waste Disposal System." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/9578.

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The depletion of more attractive thicker and easily accessible coal seams in the central Appalachia will direct attention towards the extraction of coal seams thinner than 28 in. This thesis investigates the feasibility of an integrated mining and backfilling system applicable to thin seams. Two conceptual mining systems, namely Auger mining and Self Advancing Miner, have been proposed for this purpose. Both these systems are designed to remotely mine coal from the seams. Several attempts were made in the past to mine coal in a similar fashion but were not very successful due to several problems inherent to thin seams. The lack of effective steering techniques, accurate coal/rock interface and pillar thickness detection techniques were the main shortcomings of the systems. These problems were addressed in the proposed conceptual mining systems. Several coal/rock interface and rib thickness detection techniques currently available in the market or in the prototype stage have been discussed. Recent developments in coal/rock interface detection and direction sensing techniques have good potential in alleviating the previously encountered problems. Sensitivity analyses have been performed to assess the of effect critical mining parameters on the production potential of these systems. The self advancing miner has been found to be more promising than auger mining. Conceptual panels and face layouts for both systems have been included. Two types of filling methods namely pneumatic and hydraulic are considered applicable under thin seam conditions. A backfilling technique using rubber hoses for fill placement can be applied with both methods. Sensitivity analysis have been performed to establish the relationship between face operation cost, filling cost per ton and development cost per foot. Resulting analyses indicate that panel cost per short ton of coal is more sensitive to filling cost than on development cost.
Master of Science

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30

Mollica, Fabien. "Optimization of ultra-thin Cu(In,Ga)Se2 based solar cells with alternative back-contacts." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066556/document.

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En quelques années, l'efficacité des cellules solaires à base de Cu(In,Ga)Se2 (CIGS) est passée de 20% à 22.6%. La rapidité de ce développement montre que le CIGS est un matériaux idéal pour les technologies solaires en couches minces. Pourtant, le coût de production cette technologie doit encore être abaissé pour une meilleure compétitivité. La fabrication d'un module avec une couche CIGS plus fine permettrait d'augmenter la production d'une usine et de réduire sa consommation en métaux. Ce travail de thèse vise à réduire l'épaisseur du CIGS d'un standard de 2.0-2.5 µm à une épaisseur inférieure à 500 nm sans altérer les performances des cellules. Cependant, comme rapporté dans la littérature, nous avons observé une diminution des rendements, ce que nous avons analysé en détail en comparant simulations et caractérisations d'échantillons. Celle-ci est causée à la fois par une faible absorption de la lumière dans la couche de CIGS et par un impact important du contact arrière (fortes recombinaisons et faible réflectivité). Pour dépasser ces limites, nous démontrons à la fois théoriquement et expérimentalement que le contact arrière en molybdène peut être remplacé par un oxyde transparent conducteur couplé à un miroir métallique. Nous obtenons de cette manière de meilleurs rendements de cellules. Pour atteindre ce résultat, une optimisation du dépôt de CIGS a été nécessaire. De plus, nous prouvons qu'une couche d'oxyde perforée, insérée entre le CIGS et le contact arrière, limite les recombinaisons des porteurs de charges et réduit l'influence des courants parallèles. Au final, nous avons fabriqué une cellule avec un rendement de 10.7% sur SnO2:F passivé par Al2O3
In the past three years, record efficiency of Cu(In,Ga)Se2 (CIGS) based solar cells has improved from 20% up to 22.6%. These results show that CIGS absorber is ideal for thin-film solar cells, even if this technology could be more competitive with a lower manufacture cost. The fabrication of devices with thinner CIGS absorbers is a way to increase the throughput of a factory and to reduce material consumption. This PhD thesis aims to develop cells with a CIGS thickness below 500 nm instead of the conventional 2.0-2.5 µm. However, as reported in the literature, we observed a decrease in cell performance. We carefully analyzed this effect by the comparison between simulations and sample characterizations: it is attributed, on one hand, to a lack of light absorption in the CIGS layer and, on the other hand, to an increased impact of the back-contact (high recombination and low reflectivity). To resolve these problems, we demonstrated theoretically and experimentally that the use of an alternative back-contact, other than molybdenum, such as a transparent conducting oxide coupled with a light reflector, improves the cell efficiency. To achieve this result, an optimization of the CIGS deposition was necessary. Moreover, we proved that a porous oxide layer inserted between the CIGS and the back-contact limits the charge-carrier recombination and removes some parasitic resistance. Finally, an efficiency of 10.7% was achieved for a 480-nm-thick CIGS solar cell with a SnO2:F back-contact passivated with a porous Al2O3 layer

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Sellaro, Rachel Mary. "Development and Demonstration of a Standard Methodology for Respirable Coal Mine Dust Characterization Using SEM-EDX." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/49434.

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The purpose of this thesis is to examine the potential for a more comprehensive method of analysis of coal mine dust. Respirable dust is specifically of interest due to its ability to cause occupational lung disease when miners are overexposed to airborne concentrations. A detailed standard methodology to characterize respirable mine dust is carefully investigated with the use of scanning electron microscopy with energy dispersive x-ray (SEM-EDX). In addition to a thorough description of the developed particle level characterization approach, the method is demonstrated with underground respirable dust samples collected from an underground coal mine in Central Appalachia. Results of this thesis indicate that a comprehensive dust characterization method is possible and can be efficient and effective, when standardized. This analytical approach uses measured compositions, dimensions, and shapes to produce an abundance of data in even a single sample of dust. Verification results show the method is suitable for analysis of respirable particles of common coal mine mineralogy and analysis of many samples in a timely manner. The results obtained from the underground samples in Central Appalachia reveal the quantity of information which can be generated using the developed method. The amount of data which is acquired using the more comprehensive dust characterization method may aid in understanding the health effects of various dust characteristics.
Master of Science

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Huamán, Montes Lázaro Wilder. "Aplicación de relleno hidráulico en la Mina Jimena de Compañía Minera Poderosa S.A." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2007. https://hdl.handle.net/20.500.12672/3182.

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Con la finalidad de disminuir los problemas de inestabilidad en la explotación de la Veta Jimena, de Compañía Minera Poderosa S.A. En el presente trabajo se desarrolla la evaluación técnica-económica de aplicación de Relleno Hidráulico en esta Veta. En el análisis técnico del proyecto se ha determinado que la distribución de tamaños de partículas necesarias para el transporte de la pulpa por gravedad debe aproximarse a la curva de Talvot. La pulpa tiene un 76% de sólidos con una granulometría máxima de 3/8 de pulgada; para su transporte se utiliza tubería SCH-80 Ø4” y polietileno PN 12.5 Ø4”. Luego de analizar tres alternativas para ubicar la planta, se concluyó que la mejor alternativa es ubicar la Planta de Relleno Hidráulico en el NV-2375, debido a que la diferencia de cotas respecto al nivel más bajo de explotación es de 586 m. Adicional a esta ventaja, se cuenta con una tolva de gruesos, la cual se puede acondicionar como tolva de los agregados para el relleno hidráulico. Considerando una densidad de pulpa de 1.90 kg/L, gravedad específica de 2.65 kg/L y tubería de conducción de Ø4”, se espera alcanzar un caudal de 45 a 55 m3/hora. En la evaluación económica se determinó que se requiere una inversión inicial de capital de $ 273 692, con costo de operación mensual de $ 27 690 y un ahorro anual por encima de $ 450 000.
Tesis

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Souza, Márcia Raquel Ronconi de. "Avaliação do desempenho de diferentes tipos de cobertura seca aplicados a depósitos de rejeitos de carvão." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/96400.

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Este trabalho teve como objetivo avaliar o desempenho de diferentes tipos de coberturas secas utilizadas em células experimentais preenchidas com rejeitos piritosos de carvão mineral. Quatro células de igual dimensão foram preenchidas com rejeitos piritosos, provenientes do beneficiamento de carvão mineral da Unidade Mineira II – Verdinho, pertencente à Carbonífera Criciúma S.A., situada no município de Forquilhinha, Estado de Santa Catarina. Em relação à composição das células, a primeira foi construída sem cobertura; a segunda, com somente pré-cobertura, constituída de mistura de rejeitos; a terceira, com cobertura de argila compactada; e a quarta elaborada com sistema de barreira capilar dupla. Todas foram expostas às mesmas condições meteorológicas. Para avaliação do desempenho das coberturas analisou-se o volume e características químicas e físico-químicas da água de percolação no período compreendido entre 2009 e 2010. Os parâmetros físicoquímicos considerados foram os seguintes: pH, Eh, acidez, alcalinidade e condutividade enquanto que os parâmetros químicos foram Fe, Al, Mn, Zn e sulfato. A partir dos resultados obtidos, fez-se uma análise técnica dos diferentes tipos de cobertura seca utilizados. De acordo com análise técnica constatou-se que o melhor desempenho no tocante ao volume e à qualidade da água percolada ocorreu na célula em que se utilizou cobertura com argila compactada e na célula em que se empregou cobertura do tipo barreira capilar dupla.
This work aimed to evaluate the performance of different types of dry cover employed in experimental cells filled with pyritic waste of mineral coal. Four cells with the same dimension were filled with coal tailings from the coal preparation plant of Unidade Mineira II –Verdinho, which belongs to Carbonífera Criciúma SA, located in Forquilhinha, Santa Catarina State. The first cell was constructed without any kind of cover, the second one was built with a cover composed by a mixture of coal wastes, the third one was built with a layer of compacted clay, and the forth one was constructed with a system composed by a dual-capillary barrier. All were exposed to the same meteorological conditions. To evaluate the performances of dry covers we analyzed the volume and the chemical and physicochemical characteristics of seepage between 2009 and 2010. The water was analyzed in terms of pH, Eh, acidity, alkalinity, conductivity and the concentration of Fe, Al, Mn, Zn, and sulfate. The experimental results showed that the best performance concerning the volume and the quality of the percolated water was obtained in the cell that received a cover of compacted clay and in the one that received a cover composed by dualcapillary barrier.

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Burkey, Michael F. "A REVIEW OF IRON SULFIDES AND OXIDES IN COAL MINE WASTE, HUFF RUN WATERSHED, OHIO." Kent State University Honors College / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ksuhonors1525905282950671.

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Edwards, Jamie Lee. "Netherlandish vernacular narrative painting in the age of Bruegel : 'entangling the eyes' & 'enlightening the mind'." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7703/.

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This thesis sheds new light on the origins and significance of ‘compositional inversion’ in sixteenth-century Netherlandish art. Taking Pieter Bruegel’s inverted religious narratives as primary examples of a wider phenomenon, it seeks to account for the seemingly paradoxical method of narrative obfuscation evident in these works. It does so by situating them in art theoretical, iconographic, social, political and spiritual contexts. Chapter 1 turns to the art theories of Karel van Mander, contained in the first book of Het Schilder-Boeck (1604): ‘Den Grondt … ’. Here I suggest that Bruegel’s inverted compositions exemplify an entire tradition in Netherlandish history painting – the ‘historien’ – that van Mander retroactively theorised in ‘Den Grondt’. According to his theoretical position, Netherlandish inverted ‘historien’ derive their efficacy precisely because they obscure narrative, for by doing so they ‘entangle’ the beholder’s ‘insatiable eyes’ and so encourage sustained interest in the story. Chapter 2 then examines the visual tradition in Netherlandish art that inspired Bruegel’s inverted narratives, and concludes that these works possess a distinctive formal ‘Netherlandishness’ and as such they offer fertile territory for examining Bruegel’s “vernacularity”. Finally, in Chapter 3, I argue that compositional inversion evolved as a visual counterpart to contemporary biblical exegeses, specifically Erasmus’s.

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Dulneva, Anna. "Investigating the effects of a point mutation in the TRPC3 channel, cause of cerebellar ataxia in Moonwalker mice, on the Purkinje cells in mice." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:fcb2e1ac-fbc6-4948-bc71-27f905ee09e7.

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The Moonwalker (Mwk) mouse is a mouse model of cerebellar ataxia that harbours a point mutation in the Trpc3 gene. TRPC3 is a non-selective cation channel, most highly expressed in the Purkinje cells of the cerebellum. The gain-of-function mutation in the TRPC3 protein affects the development of Purkinje cell dendrites by reducing their branching, and also leads to abnormal motor coordination and cerebellar ataxia in Mwk mice at the age of 3 weeks. The aim of this thesis was to determine how the mutation in the TRPC3 channel results in the observed pathology. Proper function of the TRPC3 channel relies on its interaction with other proteins, hence we investigated binding partners of TRPC3. The study revealed PI synthase and CaMKIV as novel interaction partners of TRPC3. PI synthase is implicated in the upstream signalling events leading to TRPC3 activation, whereas CaMKIV is activated by Ca²⁺, possibly due to TRPC3 activation. We have identified alterations in phosphorylation of several key Ca²⁺ signalling proteins (CaMKII, CaMKIV, CREB and ERK), which indicates that there are changes in Ca²⁺ homeostasis in Mwk cerebella. Down-regulation of CaMKIV and up-regulation of CREB phosphorylation occurs as early as P21, which indicates that their abnormal activity could contribute to the Mwk phenotype. Microarray analysis comparing wild-type and Mwk Purkinje cells has revealed gene expression changes, which are likely due to abnormal Ca²⁺ signalling. Genes Ipo5, Opn3 and Sv2c are up-regulated at P11; Car2 and Stk17b are down-regulated at P14; and Cntn3 is up-regulated at P18 in Mwk Purkinje cells. High quality RNA from Purkinje cells was extracted using an optimised laser-capture microdissection method. Work on the Mwk mice points to the importance of TRPC3 activity for the proper development of Purkinje cell dendrites and depicts TRPC3 as a possible target for cerebellar ataxia treatment.

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Bellettini, Carlo, Violetta Lonati, Dario Malchiodi, Mattia Monga, Anna Morpurgo, and Mauro Torelli. "What you see is what you have in mind : constructing mental models for formatted text processing." Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6461/.

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In this paper we report on our experiments in teaching computer science concepts with a mix of tangible and abstract object manipulations. The goal we set ourselves was to let pupils discover the challenges one has to meet to automatically manipulate formatted text. We worked with a group of 25 secondary school pupils (9-10th grade), and they were actually able to “invent” the concept of mark-up language. From this experiment we distilled a set of activities which will be replicated in other classes (6th grade) under the guidance of maths teachers.

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Ulldemolins, Michel. "Étude du silicium et du germanium sous forme de couche mince en tant qu’électrode négative de (micro)accumulateur lithium-ion." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR14944/document.

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Le silicium se présente comme un bon candidat d’électrode négative pour améliorer la densité d’énergie des accumulateurs Li-ion ou rendre les microaccumulateurs compatibles avec le procédé de brasure à refusion qui nécessite un recuit à 260 °C. En effet, il présente une forte capacité spécifique (3759 mAh.g-1) et sa température de fusion est élevée (1410°C). Néanmoins, de fortes variations volumiques se produisent lors du processus de lithiation/délithiation pouvant atteindre 280 %, ce qui constitue un frein majeur à son développement. Ces travaux de thèse se focalisent sur l’étude approfondie du comportement électrochimique du silicium préparé sous forme de couche mince par pulvérisation cathodique. Cette nanostructuration limite la décrépitation de la matière active, et évite l’utilisation de charges et de liants. Ainsi, elle permet d’étudier plus finement le comportement intrinsèque du matériau et révèle des phénomènes en général non détectables avec les électrodes composites
Silicon which has a theoretical capacity of 3579 mAh.g-1 and low insertion/deinsertion potentials is one of the most promising candidates to replace graphite as a negative electrode in lithium-ion batteries. Moreover, silicon could replace lithium in microbatteries to make them compatible with the solder-reflow. However, this high capacity associated with a dense material leads to high volumetric variations which are a starting point to various issues resulting in poor cycle performances. During this thesis, electrochemical behavior of silicon is evaluated on thin films electrodes. This allows avoiding the use of binder and charges, and it leads to better cycle performances which emphasizes slow phenomenon, not yet measurable on conventional composite electrode

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Scaramuzzi, Karina. "Investigação dos mecanismos de ação da sílica mesoporosa nanoestruturada SBA-15 como adjuvante." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/42/42133/tde-07062014-111900/.

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Sílicas mesoporosas, como a SBA-15, constituem-se de partículas de óxido de silício que, devido às suas propriedades físico-químicas apresentam potencial adjuvante. Para entender os mecanismos de ação da SBA-15, camundongos foram imunizados, pelas vias oral e/ou subcutânea (s.c.), com a proteína recombinante HBsAg ou ovalbumina (OVA) e apresentaram aumento significativo nos títulos de anticorpos específicos após imunização s.c. com ambos os antígenos em sílica; entretanto, somente a administração de HBsAg: SBA-15 induziu a produção de anticorpos pela via oral. O efeito da sílica na ativação de células dendríticas foi verificado após incubação com diferentes concentrações de SBA-15, indicando aumento na produção de IL-6, na proliferação e produção de IFN-g por linfócitos T após a apresentação de OVA ou seus peptídeos. A resposta de linfócitos T in vivo mostrou aumento na resposta imune celular de animais que receberam a sílica, mas não indicou a indução da resposta de linfócitos T citotóxicos. Esses resultados confirmam o efeito adjuvante da SBA-15, principalmente para a resposta de anticorpos, e indicam que a sílica pode aumentar a disponibilidade dos antígenos às APC, auxiliando na apresentação antigênica.
Amorphous silicon oxide particles named SBA-15 are promising adjuvant vectors due to its physicochemical properties and the aim of this study is to explore how they might act in promoting immune responses. Mice were orally and/or subcutaneously (s.c) immunised with the recombinant protein HBsAg or ovalbumin (OVA), showing a significant increase in the antibody titers after s.c. immunisation with both antigens in silica; however, only the administration of HBsAg: SBA-15 induced antibody production after oral immunisations. The activation of dendritic cell by silica was assessed by pulsing those cells with different concentrations of the particles, suggesting the interference of SBA-15 in the production of IL -6 and in T cell proliferation as well as IFN-g production by T lymphocytes after presentation of this protein or its peptides in vitro SBA-15 was able to enhance T cell responses in vivo but did not allow OVA to induce specific cytotoxic T lymphocyte activity. These preliminary data confirm that SBA-15 acts as an adjuvant for antibody responses and suggest that its effects may reflect enhanced availability of antigen, rather than direct effects on antigen presenting cells such as DC.

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40

Nilakantan, Gaurav. "Design and Development of an Energy Absorbing Seat and Ballistic Fabric Material Model to Reduce Crew Injury Caused by Acceleration From Mine/IED Blast." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1155041442.

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Bustamante, Murillo Aquilino. "Geomecánica aplicada en la prevención de pérdidas por caída de rocas mina Huanzalá-Cía. Minera Santa Luisa S.A." Universidad Nacional de Ingeniería. Programa Cybertesis PERÚ, 2008. http://cybertesis.uni.edu.pe/uni/2008/bustamante_ma/html/index-frames.html.

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La minería es sin duda una de las actividades de más alto riesgo que el hombre realiza. Las estadísticas indican que la causa mas frecuente de los accidentes en el interior mina es por caída de rocas. Según estadísticas de los 62 accidentes fatales ocurridos en el año 2007, aproximadamente el 23% de éstos (14 fatalidades) fue por desprendimiento de rocas. Si a esta cifra le añadimos el 13% de accidentes originados por derrumbes, deslizamientos, soplado de mineral o escombros, la segunda causa de muerte en minería, es más de 36% de fatalidades relacionadas con la inestabilidad de las rocas. Lamentablemente las consecuencias de este tipo de accidentes no son menores, por el contrario ocasionan severas lesiones al personal, incluso la muerte. Estos hechos afectan a las empresas mineras, las cuales se ven perjudicadas por la pérdida de su recurso más valioso: el hombre. Hoy en día la geomecánica juega un papel muy importante en la industria minera, en lo que es la estabilidad de la masa rocosa, esto por las aberturas que existen en las minas como consecuencia de las operaciones mineras. La geomecánica es una herramienta muy valiosa que permite entre otras cosas: Establecer dimensiones adecuadas de las labores mineras, establecer la dirección general de avance del minado a través del cuerpo mineralizado, especificar el sostenimiento adecuado, asegurar el rendimiento adecuado de la masa rocosa involucrada con las operaciones, etc. El objetivo de la presente tesis es contribuir en reducir los accidentes (incapacitantes y fatales), daños a la propiedad (equipos e instalaciones), y paradas de procesos (operaciones), a la mina Huanzalá, mediante: a) Un estudio geomecánico y de un sostenimiento adecuado de labores mineras, tales como: Pernos de anclaje, cable bolting, shotcrete por vía seca - vía húmeda y la malla metálica, b) La Implementación del Sistema de Gestión de Seguridad, basado en el Sistema de Seguridad y Salud Ocupacional OHSAS:18001-1999 y el Sistema Ambiental ISO: 14001- 2004, que viene realizando la empresa, y c) El Planeamiento Estratégico que se desarrolló años atrás en la unidad y que se debe mejorar y actualizar con algunos conceptos modernos. Herramientas muy importantes en la actualidad que vienen desarrollando muchas empresas exitosas, todo esto permitirá a la empresa Santa Luisa, realizar sus operaciones con calidad a mediano plazo. Por tanto, estas herramientas permitirán también, disminuir la ocurrencia de incidentes en las diferentes operaciones mineras
Mining is undoubtedly one of the highest risks that the man is working on. Statistics show that the most frequent cause of accidents inside the mine is rock falls. According to statistics of the 66 fatal accidents occurred in the year 2007, approximately 23% of them (14 fatalities) were by falls of rocks, if we add to this figure the 13% of accidents caused by floods, landslides, mineral or blown debris. The second leading cause of death in mining is more than 36% of fatalities associated with the volatility of rocks. Unfortunately, the consequences of such accidents are not minors, causing severe injuries to staff, including in some cases death. These facts affecting mining companies, which are handicapped by the loss of their most valuable resource; man. Today geomechanics plays a very important role in the mining industry, in what is the stability of the rock mass, this for the openings that exist in mines as a result of mining operations. The geomechanics is a valuable tool that allows inter; Establish adequate dimensions of the work mining, establishing the overall direction of advance of mining through the mineralized body, specifying the appropriate support, to ensure adequate return of the rocky mass involved with the operations, and so on. The objective of this thesis is to help reduce accidents (disabling and fatal), damage to property (equipment and facilities), and stops processes (operations), the mine Huanzalá through: a) A study and geomechanical sustaining an adequate mining tasks, such as anchor bolts, cable bolting, shotcrete through dry-wet and the metal mesh b) Implementation of Safety Management System, based on the System for Occupational Safety and Health OHSAS :18001-1999 and Environmental System ISO: 14001-2004, which is implementing the company, and c) Strategic Planning that developed years ago in the drive and needs to be improved and updated with some modern concepts, very important tools in now that many companies have developed a successful, will enable the company Santa Luisa, conduct their operations with quality in the medium term. Therefore, these tools will also, reduce the occurrence of incidents in the different mining operations

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Engh, Cameron Howard. "A See-ability Metric to Improve Mini Unmanned Aerial Vehicle Operator Awareness Using Video Georegistered to Terrain Models." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2664.pdf.

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43

Schalkwyk, Hugh Je-Marco. "Assessment controls on reservoir performance and the affects of granulation seam mechanics in the Bredasdorp Basin, South Africa." Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3459_1183461991.

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The Bredasdorp Basin is one of the largest hydrocarbon producing blocks within Southern Africa. The E-M field is situated approximate 50 km west from the FA platform and was brought into commission due to the potential hydrocarbons it may hold. If this field is brought up to full producing capability it will extend the lifespan of the refining station in Mosselbay, situated on the south coast of South Africa, by approximately 8 to 10 years. An unexpected pressure drop within the E-M field caused the suite not to perform optimally and thus further analysis was imminent to assess and alleviate the predicament. The first step within the project was to determine what might have cause the pressure drop and thus we had to go back to cores drilled by Soekor now known as Petroleum South Africa, in the early 1980&rsquo
s.

Analyses of the cores exposed a high presence of granulation seams. The granulation seams were mainly subjected within sand units within the cores. This was caused by rolling of sand grains over one another rearranging themselves due to pressure exerted through compaction and faulting, creating seal like fractures within the sand. These fractures caused these sand units to compartmentalize and prohibit flow from one on block to the next. With advance inquiry it was discovered that there was a shale unit situated within the reservoir dividing the reservoir into two main compartments. At this point it was determined to use Petrel which is windows based software for 3D visualization with a user interface based on the Windows Microsoft standards. This is easy as well as user friendly software thus the choice to go with it. The software uses shared earth modeling tool bringing about reservoir disciplines trough common data modelling. This is one of the best modelling applications in the available and it was for this reason that it was chosen to apply within the given aspects of the project A lack of data was available to model the granulation seams but with the data acquired during the core analyses it was possible to model the shale unit and factor in the influences of the granulation seams to asses the extent of compartmentalization. The core revealed a thick shale layer dividing the reservoir within two sections which was not previously noted. This shale layer act as a buffer/barrier restricting flow from the bottom to the top halve of the reservoir. This layer is thickest at the crest of the 10km²
domal closure and thins toward the confines of the E-M suite. Small incisions, visible within the 3 dimensional models could serve as a guide for possible re-entry points for future drilling. These incisions which were formed through Lowstand and Highstand systems tracts with the rise and fall of the sea level. The Bredasdorp Basin consists mainly of tilting half graben structures that formed through rifting with the break-up of Gondwanaland. The model also revealed that these faults segregate the reservoir further creating bigger compartments. The reservoir is highly compartmentalized which will explain the pressure loss within the E-M suite. The production well was drilled within one of these compartments and when the confining pressure was relieved the pressure dropped and the production decrease. As recommendation, additional wells are required to appraise the E-M structure and determine to what extent the granulation seems has affected fluid flow as well as the degree of sedimentation that could impede fluid flow. There are areas still containing untapped resources thus the recommendation for extra wells.

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Ruchert, Cassius Olivio Figueiredo Terra. "Estudo da inferência de carregamento em histórias de vôos simulados na liga de Al aeronáutico SAE-AMS 7475 T7351." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-22092008-131854/.

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Este trabalho discutiu o estudo da inferência de carregamento e a reconstrução fratográfica da taxa de propagação da trinca por fadiga em histórias de vôos simulados do tipo Twist, mini-Twist, Falstaff e mini-Falstaff. O material estudado foi uma liga de alumínio de grau aeronáutico SAE-AMS 7475 T7351 na qual foram obtidas as propriedades mecânicas a partir dos ensaios de tração e dureza, análise química, metalográfica. Foram realizados ensaios de amplitude constante de carregamento em corpos de prova com geometria tipo C(T) extraídos de um bloco e ensaios de amplitude variável em corpos de prova com geometria tipo M(T) extraídos de uma placa. Corpos de prova do tipo C(T) foram extraídos da orientação L-T e T-L, à temperatura ambiente com diferentes espessuras para a realização de ensaios de propagação de trinca por fadiga (da/dN vs. ΔK) com distintos valores de razão de carregamento,R (0,1;0,3; 0,5; 0,7 e 0,8) de acordo com a norma ASTM-E647 (1993). Foram realizados dois tipos de ensaios de fadiga com amplitude constante de carregamento. Primeiro, o ensaio com ΔP constante para obtenção dos dados dos estágios II e III das curvas da/dN vs. ΔK para distintos valores de R e, posteriormente, o ensaio com ΔK constante e R crescente para ser utilizado no estudo da inferência de carregamento de amplitude constante a partir da relação entre a morfologia da estria, H/s e a razão de carregamento R. Adicionalmente foram realizados ensaios de tenacidade à fratura, nas direções L-T e T-L, conforme a norma ASTME1820 (1999). As taxas de propagação macroscópica e microscópica foram comparadas e boas correlações foram obtidas para um intervalo entre 0,1 a 1,0 μm/ciclo, mesmo com distintos R. Através da técnica proposta por Berkovitz (1995), o espectro de carregamento foi estimado para distintos valores de R, através da técnica de parametrização do fator K e os resultados foram comparados ao espectro de carregamento real imposto pela máquina de ensaio. Após os ensaios de amplitude constante de carregamento foram realizados ensaios de amplitude variável com a aplicação em corpos de prova M(T) de espectros de vôos simulados padronizados pela NLR do tipo Twist e Falstaff e seus vôos reduzidos, mini-Twist e mini- Falstaff, em uma máquina servohidráulica de ensaios dinâmicos. A partir destes ensaios notou-se que suprimir os vôos com os carregamentos menos severos influencia muito a vida da propagação da trinca de fadiga, quando vôos simulados do tipo Twist e mini-Twist, fato este não observado para o Falstaff e mini-Falstaff. Foi possível observar também o efeito da aceleração e desaceleração da trinca por fadiga observando os gráficos de d2a/dvôo vs. a obtidos dos ensaios de amplitude variável. Foi realizado um estudo da superfície de fratura do CP05 por meio da técnica fractográfica do reconhecimento de blocos marcadores sendo possível mostrar uma satisfatória reconstituição da taxa de propagação da trinca por fadiga de vôo simulado do tipo Falstaff por meio de medidas das marcações na superfície de fratura dos vôos mais severos, realizadas em imagens obtidas por MEV.
The loading inference and the fractographic reconstruction of fatigue crack propagation rate in simulated flight stories, as Twist, mini-Twist, Falstaff and mini-Falstaff were investigated in this work. The studied material was an aluminum alloy SAE-AMS 7475 T7351. Tensile and hardness tests were carried out in order to determine mechanical properties, as well as chemical and microstructure analysis of the material. C(T) specimens were extracted from a block of material for constant amplitude load testing and M(T) specimens were extracted from a plate and were tested in variable amplitude loading. The curves (da/dN vs. ΔK) for constant-amplitude loading were obtained from fatigue crack propagation tests performed in L-T and T-L directions in C(T) specimens for R (0.1; 0.3; 0.5; 0.7 and 0.8), at room temperature, according to ASTM-E647 (1993). Two different constant loading fatigue tests were performed. At constant ΔP and distinct values of R for obtaining data of stages II and III of da/dN - ΔK curves; and at constant ΔK and increasing the R ratio to be used in the inference of constant amplitude loading in the relation of H/s striation morphology (obtained from fractographic images) and the loading ratio, R. Additionally, fracture toughness tests were executed in T-L and L-T directions, according to ASTM-E1820 (1999). The macroscopic and microscopic fatigue crack propagations were compared and good correlation was obtained for the range 0.1-1.0 μm/cycle, for all R values. By using the K factor parametrization method, Berkovitz (1995), the loading spectrum was estimated for the distinct R-values and the results were compared to the actual spectrum imposed by the test machine. Variable amplitude tests were performed in M(T) specimens by applying simulating flight spectra normalized by NLR, as Twist, mini-Twist, Falstaff and mini-Falstaff, in a servohydraulic test machine MTS, in which a Flextest GT controller was coupled. The suppression of less severe loading flights showed a great influence in fatigue crack propagation life, in simulated flight tests Twist and mini-Twist, but not in Falstaff and mini-Falstaff. The acceleration and slowing down of fatigue crack were observed in the d2a/dflight - a curve obtained from variable loading tests. The fractured surfaces of some samples were examined by the fractographic technique of blocking marks recognition. A good reconstitution of fatigue crack propagation rate of a simulated flight like Falstaff was obtained by the measurements of marks in the fracture surfaces of the more severe flights, in MEV images.

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Ramírez, Tixi Ignacio Rodrigo. "Diseño y desarrollo de un nuevo reporte compacto y automático de planificación mina División Los Bronces, Anglo American S.A." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/169973.

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Memoria para optar al título de Ingeniero Civil de Minas
El presente trabajo de título entrega el proceso de diseñar, desarrollar e implementar un reporte automático, que guste y sirva, para la planificación de operaciones en la División Los Bronces de AngloAmerican. La reportabilidad es fundamental para poder observar rendimientos y cumplimientos de los indicadores clave en una faena minera. Ésta cobra especial relevancia en el área de planificación mina para poder hacer la retroalimentación con la operación, observar los desvíos en la secuencia minera y tomar acciones para recuperar la senda de ésta. Actualmente en la Superintendencia de Planificación de Operaciones se utilizan reportes de otras gerencias para obtener los indicadores necesarios para la revisión interna de los planes y programas de operaciones. Además, los reportes generados desde el área son realizados de manera manual por control de calidad, lo que provoca una pérdida innecesaria de tiempo. Por esto se buscó la forma de recopilar esta información diseminada, ordenarla y mostrarla en un reporte que guste y sea útil para el área, además de ser entregado a los interesados de manera automática, utilizando como plataforma de diseño el Microsoft Excel, utilizando datos obtenidos desde dos servidores: el sistema de gestión de flota Dispatch y el PI System® que captura datos en línea desde la planta. Los diseños del reporte variaron en formato, indicadores a mostrar y la forma en que se presentaban. Esto fue variando dependiendo de las opiniones dentro del área de planificación o por las complicaciones que implicaba agregar algún elemento al reporte. Luego de varias iteraciones en el diseño, se llega a una versión final que integra datos de la mina (extracción por fase, mineral cargado, vaciado a Stocks), chancado (alimentación, cantidad y calidad de ésta), y planta con el cobre fino despachado. Los indicadores se presentan en forma de tablas y gráficos de control, los cuales permiten ver tanto el cumplimiento global del mes, como el diario. Esto último permite observar y analizar tendencias a lo largo del mes, siendo una herramienta muy útil para identificar causas especiales en el KPI analizado. Para cargar el reporte se utilizó el Sistema Automático de Entrega de Reportes (que utiliza como base el PI System®) el cual tiene como datos de entrada el reporte en Excel, los usuarios a entregar, el nombre del reporte y el horario de entrega. El mayor punto a favor de este sistema es que los reportes se pueden modificar y estilizar a gusto del usuario, para luego ser cargado nuevamente. Finalmente, el aporte ingenieril que se generó al implementar este reporte automático fue el hecho de que se lograron unificar conceptos e indicadores de distintas áreas productivas en un solo lugar, pudiéndose vislumbrar fácilmente los posibles desvíos en la secuencia minera y en la producción de cobre, dando la oportunidad de levantar alertas tempranas a éstas, convirtiéndose en una herramienta de gestión que facilite la toma de decisiones respecto a estas desviaciones.
Anglo American Sur S. A.

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Schwartz, Julie Ann. "Systemic and immune toxicity induced by low concentration chronic fuel oil exposure in American mink (Mustela vison), a surrogate model for the Southern sea otter (Enhydra lutris nereis) /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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Daniel, Blakemore. "Insights into the History of Pyrite Mineralization at the Round Mountain Gold Mine, Nevada: A Detailed Microanalytical Study of the Type 2 Ore." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami15962291791253.

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Gadepalli, Venkat Sundar. "ISOLATION AND CHARACTERIZATION OF MULTIPOTENT LUNG STEM CELLS FROM p53 MUTANT MICE MODELS." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3644.

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Recent advances in understanding lung biology have shown evidence for the existence of resident lung stem cells. Independent studies in identifying and characterizing these somatic lung stem cells have shown the potential role of these cells in lung repair and regeneration. Understanding the functional characteristics of these tissue resident stem/progenitor cells has gained much importance with increasing evidence of cancer stem cells, cells in a tumor tissue with stem cell characteristics. Lung cancer is most commonly characterized by loss of p53 function which results in uncontrolled cell divisions. Incidence of p53 point mutations is highest in lung cancer, with a high percentage of missense mutations as a result of tobacco smoking. Certain point mutations in p53 gene results in its oncogenic gain of functions (GOF), with enhanced tumorigenic characteristics beyond the loss of p53 function. However, there are no available data on characterization of lung stem cells carrying GOF mutations and correlating them with those of normal stem cells, in this study, for the first time we show that percentage of Sca-1 expressing subpopulation is significantly higher in the lungs of mice carrying p53 GOF mutations than those in lungs isolated from p53+/+ wild type mice. Further, we successfully established lung cells differentially expressing two cell surface markers, Sca-1 and PDGFR-α, with results demonstrating existence of different subpopulations of cells in the lung. Results from our project demonstrate the importance of p53 GOF mutations as correlated with specific lung cell subpopulations.

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Esposito, Serena. "Marins et bateliers dans l'Égypte du IIIe millénaire av. J.-C. : histoire institutionnelle, économique et sociale." Thesis, Sorbonne université, 2020. http://www.theses.fr/2020SORUL056.

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Pendant l’Ancien Empire et la Première Période intermédiaire, l’augmentation progressive des activités nautiques individuelles et l’accès à des embarcations privées s’accompagnent d’opérations navales mises en place par le pouvoir central. Ces missions impliquaient le recrutement de chefs d’équipes spécialisés dans la navigation, mais aussi dans la gestion humaine des diverses catégories d’officiers présents à bord. En effet, l’activité de l’ensemble de l’équipage ne se limitait pas à la navigation à proprement parler : les marins étaient aussi directement impliqués dans les différentes phases des misions terrestres. Ils étaient présents dans des opérations militaires et commerciales extérieures ; ils pouvaient aussi intervenir dans le cadre des grands chantiers royaux et dans l’extraction de matières premières dans les mines et carrières. Les sources épigraphiques montrent la capacité d’adaptation de ces fonctionnaires dans différents contextes d’opération. Cette thèse propose une analyse nuancée du rôle administratifs de ces hommes. L’objectif principal est d’illustrer les relations horizontales entre les différents officiers de la marine (hiérarchie interne) et leurs liens verticaux avec les hautes institutions de l’État. La perspective générale est celle d'une institution maritime temporaire dont les acteurs - issus de milieux sociaux différents - étaient occasionnellement et périodiquement impliqués
During the Old Kingdom and the First intermediate period, in addition to a progressive increase of individual nautical activities giving access to private property of boats and skiffs, an institutional control of some nautical operations implied the recruitment of specialized bureaucrats controlling different categories of crew officials. Their activities were not limited to those on board of the ship: sailors and boatmen were indeed involved in different kinds of land missions. They participated in military and commercial operations in the peripheral regions; they were also in charge of seasonal and periodical tasks in building projects and in quarries, organising the boarding and the transportation of heavy materials from the point of extraction to the point of use. This PhD thesis suggests a nuanced analysis of the administrative role of the most important categories of officials involved in the naval sphere. The main goal is to illustrate the horizontal relations between naval officers and their vertical links with the high state institutions. The general perspective is that of a “temporary” maritime institution whose actors – stemming from different social milieu – were occasionally involved

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Nascimento, Herynson Nunes. "Caracterização tecnológica de materiais estéreis com elevado teor de PPC e P da Mina de Alegria da Samarco Mineração S.A." Universidade Federal de Minas Gerais, 2014. http://hdl.handle.net/1843/BUOS-9LVRGJ.

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Samarco holds a reserve of 3.08 billion tons, the iron formation being cut into ore and waste. Iron formations presenting P and LOI contents lower than 0.097% and 7.7%, respectively, are considered ore. Contents higher than those levels characterize the material as waste. This study addressed the possibility of generating information to support Samarco´s decision on the future concentration of materials presenting high contents of LOI and P, currently considered as wastes, representing approximately 90 million tons of Alegria North and South mines. The work samples are "ores" presenting P grade above 0.097% and LOI content between 6% and 7.7%. Technological characterization tests were performed, simulating at bench scale the beneficiation processes at Samarco. The results were compared with those achieved with a reference sample. It was observed that the samples under investigation required higher energy consumption in the primary grinding, resulting in lower productivity. The recovery levels in desliming and conventional flotation were lower. However, the flotation kinetics was good and the liberation degree of quartz in all size fractions was higher than 90%. The productivity in the secondary grinding was low and the particles size was too coarse to meet the Blaine currently practiced. It was impossible to reach the final specification of silica in the concentrate after regrinding. The settling tests indicated no future problems in the stages of slimes, tailings, and concentrate thickening. The product of primary grinding and the desliming underflow were also submitted to wet high intensity magnetic separation using a Minimag apparatus aiming at improving the concentration. The magnetic separation applied to the Alegria North and South samples indicated that the materials present paramagnetic behavior. According to the results, introducing a magnetic separation stage after the primary grinding might enrich significantly the flotation feed, besides roughing a significant amount of silica.
A Samarco Mineração possui uma reserva de 3,08 bilhões de toneladas, sendo que a formação ferrífera é cortada em minério e estéril. É caracterizado como minério toda formação ferrífera que estiver dentro da cava com teores de P menor do que 0,097% e PPC menor do que 7,7%. Serão considerados como estéreis materiais com teor de P maior do que 0,097% ou com teor de PPC maior do que 7,7%. Este trabalho investigou a possibilidade de gerar informações, para subsidiar a Samarco no aproveitamento futuro de materiais considerados estéreis pelo elevado teor de PPC e P (aproximadamente 90 milhões de toneladas) das minas de Alegria Sul e Norte. As amostras do trabalho são minérios cortados apenas por fósforo, entretanto com PPC maior que 6% e menor que 7,7%. Foram feitos testes de caracterização tecnológica, simulando em bancada os processos de beneficiamento da Samarco Mineração. Os resultados foram comparados com os obtidos com uma amostra de referência. Observou-se que as amostras estudadas requererem maior consumo energético na moagem primária, implicando em uma menor produtividade. Essas apresentam índices inferiores de recuperação na deslamagem e flotação convencional. Entretanto, apresentaram boa cinética de flotação e o grau de liberação do quartzo maior que 90% para todas as frações granulométricas. As amostras também apresentaram baixa produtividade na moagem secundária e granulometria grossa para o atendimento da meta de Blaine praticada atualmente. Não foi possível a obtenção da especificação final de sílica no concentrado após a remoagem. Os testes de sedimentação não indicaram problemas nas etapas de espessamento de lama, rejeito e concentrado. Foram realizados também ensaios em escala de bancada para separação magnética utilizando Minimag (WHIMS), no produto da moagem primária e no underflow da deslamagem, objetivando avaliar a possibilidade de uma melhor concentração desses materiais. As separações magnéticas realizada nas Amostras Norte e Sul provaram que o material apresenta comportamento paramagnético. Pelos resultados obtidos, inserir uma separação magnética após a moagem primária enriqueceria substancialmente a alimentação da flotação, além de desbastar grande parte da sílica presente.

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Dissertations / Theses on the topic 'Sea Mine'

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