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Sample records for ore group north

  1. Challenges facing the North American iron ore industry

    Science.gov (United States)

    Jorgenson, J.D.

    2005-01-01

    During the 20th century, the iron ore mining industries of Canada and the United States passed through several periods of transformation. The beginning of the 21st century has seen yet another period of transformation, with the economic failure of a number of steel companies, the acquisition of their facilities by more viable steelmakers, and the consolidation of control within the North American iron ore industry. Changes in Canadian and United States iron ore production and the market control structure involved are analysed. The consolidation of ownership, formation of foreign joint ventures within Nordi America, planned divestitures of upstream activities by steelmakers, and industry changes made to ensure availability of feedstocks will be reviewed. The ttaditional isolation of the Canadian and United States iron ore operations and their strong linkage to downstream steel production will be discussed in the context of a changing global economy. Management-labour conflicts that have taken place and agreements made during 2000 through 2004 will be discussed in the context of the economic environment leading up to these agreements. Cooperative agreements between competing Canadian and United States companies to resolve client needs in processing and blending will be examined. A joint industry-government project designed to use new technology to produce direct reduced iron nuggets of 96 - 98 per cent iron content using non-coking coals will also be assessed. Changes in iron ore transportation methods, ownership and infrastructure will be reviewed for both rail and inland waterway transport between Canadian and United States companies. A brief analysis of social and environmental issues relating to sustainable development of the Canadian-United States iron ore industry will be included.

  2. The North American iron ore industry: a decade into the 21st century

    Science.gov (United States)

    Jorgenson, John D.; Perez, A. A

    2011-01-01

    During the 20th century, the iron ore mining industries of Canada and the United States passed through periods of transformation. The beginning of the 21st century has seen another period of transformation, with the failure of a number of steel companies and with consolidation of control within the North American iron ore industry. Canadian and United States iron ore production and the market control structure involved are changing rapidly. Consolidation of ownership, formation of foreign joint ventures, divestitures of upstream activities by steelmakers, and industry changes to ensure availability of feedstocks all played a role in recent developments in the North American iron ore industry. Canadian and U.S. iron ore operations and their strong linkage to downstream production, although isolated, must also be considered within the context of the changing global economy. Projects using new technology to produce direct reduced iron nuggets of 96-98% iron content and other projects designed to produce steel at minesites may once again change the face of the iron ore industry. Social and environmental issues related to sustainable development have had a significant effect on the North American iron ore industry.

  3. 78 FR 47317 - Ore Knob Mine Superfund Site; Laurel Springs, Ashe County, North Carolina; Notice of Settlement

    Science.gov (United States)

    2013-08-05

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9843-3; CERCLA-04-2013-3759] Ore Knob Mine Superfund Site; Laurel Springs, Ashe County, North Carolina; Notice of Settlement AGENCY: Environmental Protection Agency... settlement with Herbert N. Francis concerning the Ore Knob Mine Superfund Site located in Laurel Springs...

  4. The North Cotentin radioecology group

    International Nuclear Information System (INIS)

    Miserey, Y.; Pellegrini, P.

    2007-01-01

    On January 11., 97, the epidemiologist Jean-Francois Viel publishes a study on the risks of leukaemia of the children in the canton of Beaumont-Hague (Manche), situated near the site of the reprocessing plant of spent fuel of Cogema. Advancing the hypothesis of a link between the exposure to radioactive waste and the appearance of case of the disease in the region, the study creates at once the scandal within the scientific community and within the general public. Worrying about the affair, Ministers in charge of environment and health decide to create a first scientific commission in which participates Jean-Francois Viel. But the tensions are so important within this association that at the end of six months its president decides to resign. It is at this moment there of the story of this debate that the evidence was imperative: it was necessary to innovate by putting around the table experts of any origin to estimate the risks of leukaemia which can result from exposures of the populations of the North Cotentin to ionizing radiations. Placed under Annie Sugier presidency, then manager of the protection in the I.P.S.N. (Institute of protection and nuclear safety), the pluralistic group, called 'North Cotentin radioecology group' ( G.R.N.C.), who collected 50 experts, represents an innovative way of entering in the evaluation and the management of the risks and in the acceptability of the uncertainty. The originality of the G.R.N.C. lies in a critical step as exhaustive as possible which allows to end in the production of shared knowledge. The direction the economic studies and the environmental evaluation of the Ministry of ecology and sustainable development considered important to make the story of the G.R.N.C. better known. To bring to a successful conclusion this project of edition, a work group was set up by the service of Research) and the forward-looking and the drafting of the work was entrusted to a journalist, Yves Miserey and to an ethnologist, Patricia

  5. The Use of Ground Penetrating Radar to Exploring Sedimentary Ore In North-Central Saudi Arabia

    Science.gov (United States)

    Almutairi, Yasir; Almutair, Muteb

    2015-04-01

    Ground Penetrating Radar (GPR) is a non-destructive geophysical method that provides a continuous subsurface profile, without drilling. This geophysical technique has great potential in delineating the extension of bauxites ore in north-central Saudi Arabia. Bauxite is from types sedimentary ores. This study aim to evaluate the effectiveness of Ground Penetrating Radar (GPR) to illustrate the subsurface feature of the Bauxite deposits at some selected mining areas north-central Saudi Arabia. Bauxite is a heterogeneous material that consists of complex metals such as alumina and aluminum. An efficient and cost-effect exploration method for bauxite mine in Saudi Arabia is required. Ground penetrating radar (GPR) measurements have been carrying out along outcrop in order to assess the potential of GPR data for imaging and characterising different lithological facies. To do so, we have tested different antenna frequencies to acquire the electromagnetic signals along a 90 m profile using the IDS system. This system equipped with a 25 MHz antenna that allows investigating the Bauxite layer at shallow depths where the clay layers may existed. Therefore, the 25 MHz frequency antenna has been used in this study insure better resolution of the subsurface and to get more penetration to image the Bauxite layer. After the GPR data acquisition, this data must be processed in order to be more easily visualized and interpreted. Data processing was done using Reflex 6.0 software. A series of tests were carried out in frequency filtering on a sample of radar sections, which was considered to better represent the entire set of data. Our results indicated that the GPR profiling has a very good agreement for mapping the bauxite layer depth at range of 7 m to 11 m. This study has emphasized that the high-resolution GPR method is the robust and cost-effect technique to map the Bauxite layer. The exploration of Bauxite resource using the GPR technique could reduce the number of holes to

  6. The uranium ore deposits of the pine creek geosyncline in North Territory, Australia

    International Nuclear Information System (INIS)

    Kneuper, G.K.; Clasen, D.

    1980-01-01

    The geological history of the Pine Creek geosyncline is reviewed, and recent research findings and model assumption on the formation of uranium ore deposits are presented. The geological similarities between the Alligator River uranium ore district and the Athabasca Lake district in Saskatchewan, Canada, are pointed out. Present geographic and climatic differences between these two uranium districts and the consequences of these differences for uranium exploration are discussed. The uranium mining activities planned in Australia are illustrated by the example of the Ranger uranium deposit. (orig.) [de

  7. POTENTIALLY UNSTABLE SLOPE ABOVE ORE PROCESSING PLANT IN THE "OČURA" DOLOMITE QUARRY (LEPOGLAVA, NORTH CROATIA

    Directory of Open Access Journals (Sweden)

    Karlo Braun

    1993-12-01

    Full Text Available The complex engineering investigation, in the nearest surroun-dig of the conditionally stable high slope, close to ore processing facilities in the dolomite quarry »Očura« near Lepoglava (North Croatia, was carried out. Studying the tectonic features of the rock mass, discontinuities referent to the slope stability, was found out. Rock fragment size was measured and data processed using statistical design. According to rock fragment mean values, velocity of the longitudinal seismic waves was predicted. This values was compared with velocities of the longitudinal seismic waves, determined using gcophisical refraction seismic method. Physical and mechanical properties of the dolomite rock mass, considering longitudinal and transversal seismic wave velocities, and »RMR«-classification was assesed. All the results indicate, that the slope above the ore processing facilities should be consider as conditionally stable, with real probability to get unstable under the vibrations caused by blasting, during the exploitation in the field, close behind the investigated slope (the paper is published in Croatian.

  8. Neoarchean granite-greenstone belts and related ore mineralization in the North China Craton: An overview

    Directory of Open Access Journals (Sweden)

    Li Tang

    2018-05-01

    Full Text Available Tectonic processes involving amalgamations of microblocks along zones of ocean closure represented by granite-greenstone belts (GGB were fundamental in building the Earth's early continents. The crustal growth and cratonization of the North China Craton (NCC are correlated to the amalgamation of microblocks welded by 2.75–2.6 Ga and ∼2.5 Ga GGBs. The lithological assemblages in the GGBs are broadly represented by volcano-sedimentary sequences, subduction-collision related granitoids and bimodal volcanic rocks (basalt and dacite interlayered with minor komatiites and calc-alkalic volcanic rocks (basalt, andesite and felsic rock. The geochemical features of meta-basalts in the major GGBs of the NCC display affinity with N-MORB, E-MORB, OIB and calc-alkaline basalt, suggesting that the microblocks were separated by oceanic realm. The granitoid rocks display arc signature with enrichment of LILE (K, Rb, Sr, Ba and LREE, and depletion of HFSE (Nb, Ta, Th, U, Ti and HREE, and fall in the VAG field. The major mineralization includes Neoarchean BIF-type iron and VMS-type Cu-Zb deposits and these, together with the associated supracrustal rocks possibly formed in back-arc basins or arc-related oceanic slab subduction setting with or without input from mantle plumes. The 2.75–2.60 Ga TTG rocks, komatiites, meta-basalts and metasedimentary rocks in the Yanlingguan GGB are correlated to the upwelling mantle plume with eruption close to the continental margin within an ocean basin. The volcano-sedimentary rocks and granitoid rocks in the late Neoarchean GGBs display formation ages of 2.60–2.48 Ga, followed by metamorphism at 2.52–2.47 Ga, corresponding to a typical modern-style subduction-collision system operating at the dawn of Proterozoic. The late Neoarchean komatiite (Dongwufenzi GGB, sanukitoid (Dongwufenzi GGB and Western Shandong GGB, BIF (Zunhua GGB and VMS deposit (Hongtoushan-Qingyuan-Helong GGB have closer connection to a combined

  9. Komatiites and nickel sulfide ores of the Black Swan area, Yilgarn Craton, Western Australia. 4. Platinum group element distribution in the ores, and genetic implications

    Science.gov (United States)

    Barnes, Stephen J.

    2004-11-01

    The Black Swan komatiite sequence, in the Eastern Goldfields province of the Archaean Yilgarn Craton in Western Australia, is a body of dominantly olivine-rich cumulates with lesser volumes of spinifex textured rocks, interpreted as a section through an extensive komatiite lava flow field. The sequence hosts a number of nickel sulfide orebodies, including the Silver Swan massive shoot and the Cygnet and Black Swan disseminated orebodies. The massive sulfide orebodies of the Black Swan Succession are pervasively depleted in all platinum group elements (PGEs), particularly Pt and Pd, despite very high Ni contents. This depletion cannot be explained by R-factor variations, which would also require relatively low Ni tenors. The PGE depletion could be explained in part if the ores are enriched in a monosulfide solid solution (MSS) cumulate component, but requires some additional fractional segregation of sulfide melt upstream from the site of deposition. The Silver Swan orebody shows a remarkably consistent vertical zonation in PGE contents, particularly in Ir, Ru, Rh, Os, which increase systematically from very low levels at the stratigraphic base of the sulfide body to maxima corresponding roughly with the top of a lower layer of the orebody rich in silicate inclusions. Platinum shows the opposite trend, but is somewhat modified by remobilisation during talc carbonate alteration. A similar pattern is also observed in the adjacent White Swan orebody. This zonation is interpreted and modelled as the result of fractional crystallisation of MSS from the molten sulfide pool. The strong IPGE depletion towards the base of the orebody may be a consequence of sulfide liquid crystallisation in an inverted thermal gradient, between a thin rapidly cooling upper rind of komatiite lava and a hot substrate.

  10. Filtration aids in uranium ore processing

    International Nuclear Information System (INIS)

    Ford, H.L.; Levine, N.M.; Risdon, A.R.

    1975-01-01

    A process of improving the filtration efficiency and separation of uranium ore pulps obtained by carbonate leaching of uranium ore which comprises treating said ore pulps with an aqueous solution of hydroxyalkyl guar selected from the group consisting of hydroxyethyl and hydroxypropyl guar in the amount of 0.1 and 2.0 pounds of hydroxyalkyl guar per ton of uranium ore

  11. Lavalleja group (Uruguay) a neoproterozoic metavolcanic-sedimentary sequence: ore deposits

    International Nuclear Information System (INIS)

    Sanchez Bettucci, L.; Preciozzi, F.; Ramos, V.

    2003-01-01

    The Lavalleja meta volcano-sedimentary Group, exposed along the Dom Feliciano Belt, is located in the southeast of Uruguay and formed by meta gabbros, basic and acid meta volcanic rocks. It was developed during late Proterozoic-Early Paleozoic Brasiliano orogeny. Based on the geochemical signature, Sánchez-Bettucci et al. (2001) suggested a back-arc basin tectonic setting. The metamorphic grade increases to the southeast, ranging from very low grade to lower green schist facies in the Minas formation, to lower amphibolite facies in the Fuente del Puma and Zanja del Tigre Formations (Sánchez-Bettucci et al., 2001). The metamorphic mineral assemblages correspond to a low-pressure regional metamorphism associated with a high thermal gradient (Sánchez-Bettucci et al., 2001).A compressive deformational event, that probably corresponds to the basin closure of the Lavalleja Group during a continental collision was recognized. The petrology, geochemistry, metamorphism grade, and tectonic setting are consistent with a back-arc basin as suggested by Sánchez-Bettucci et al. (2001)

  12. Exposure of critical group of population to water radionuclides in area affected by uranium ore mining

    Energy Technology Data Exchange (ETDEWEB)

    Hladka, E; Zavadsky, M; Solnicka, H; Heroldova, J

    1985-08-01

    Waste waters from the uranium industry are decontaminated and then discharged into water courses. Inhabitants of the nearest village on the river form the critical group with regard to radiation burden. The critical radionuclides are Usub(nat), Ra 226, Pb 210 and Po 210 whose concentrations were determined in drinking water, in the water course and in plants watered with water from the river. From obtained data on the consumption of foods of own production and of water for drinking and cooking, a weighted sum was made of the intake of critical radionuclides per year on the conservative assumption that ingestion is the sole form of intake (permissible ingestion under Notice 59/72, Coll. of Laws). Under the said criteria the intake of radionuclides from water and foods of own production is for the critical population group 27 times less than the permissible intake for the population. Decontaminated waste waters from the operation of uranium industries contribute to the radiation burden of the population only negligibly. Radionuclides from the investigated sources represent a minute fraction of permissible intake.

  13. Ore sorting

    International Nuclear Information System (INIS)

    Hawkins, A.P.; Richards, A.W.

    1982-01-01

    In an ore sorting apparatus, ore particles are bombarded with neutrons in a chamber and sorted by detecting radiation emitted by isotopes of elements, such as gold, forming or contained in the particles, using detectors and selectively controlling fluid jets. The isotopes can be selectively recognised by their radiation characteristics. In an alternative embodiment, shorter life isotopes are formed by neutron bombardment and detection of radiation takes place immediately adjacent the region of bombardment

  14. Uranium ores

    International Nuclear Information System (INIS)

    Poty, B.; Roux, J.

    1998-01-01

    The processing of uranium ores for uranium extraction and concentration is not much different than the processing of other metallic ores. However, thanks to its radioactive property, the prospecting of uranium ores can be performed using geophysical methods. Surface and sub-surface detection methods are a combination of radioactive measurement methods (radium, radon etc..) and classical mining and petroleum prospecting methods. Worldwide uranium prospecting has been more or less active during the last 50 years, but the rise of raw material and energy prices between 1970 and 1980 has incited several countries to develop their nuclear industry in order to diversify their resources and improve their energy independence. The result is a considerable increase of nuclear fuels demand between 1980 and 1990. This paper describes successively: the uranium prospecting methods (direct, indirect and methodology), the uranium deposits (economical definition, uranium ores, and deposits), the exploitation of uranium ores (use of radioactivity, radioprotection, effluents), the worldwide uranium resources (definition of the different categories and present day state of worldwide resources). (J.S.)

  15. The North sea, one of the group's anchorage points

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    The North Sea is one of the pillars of the Elf Aquitaine group's Exploration-Production strategy. The most recent start-up in the North Sea, last february, concerned the Froy field where Elf Petroleum Norge (AS) is an operator with a 24.573 % interest alongside Statoil, Total Norge AS (15.2346 %) and Norsk Hydro. The first gas sales occurred on June 15, as scheduled. The oil production marketed by Elf (net of royalties) remained stable at 13.9 Gm 3 . At january 1,1995, Elf Aquitaine's mining area covered a gross surface area of 435,894 km 2 . In countries where the group is already established, the policy is : - to withdraw from exploration licenses considered as being the least promising in terms of discovery or profitability; - to concentrate on sectors where the existing production means allow for an optimisation of later developments ; - to penetrate more extensive exploration areas with good targets. In the British zone, the additional reserves revealed in the Elgin and Franklin condensate fields have doubled the initial forecast, placing the former among the major fields. All the discoveries made in the British zone have allowed the group to renew productions until now. Elf's production in Piper, Saltire, Chanter is 100,000 b/d which is added to the production of the Claymore and Scapa fields (100,000 b/d). The Flotta terminal processes the crude coming from these fields to which is added the production from the neighbouring fields of Tartan (Texaco) and Ivanhoe-Rob Roy (Amerada Hess), i.e. a total of more than 300,000 b/d. Other than Elgin or the Viking Graben, the future of the Elf group in Great Britain will most certainly come from the West Shetlands and the Irish Sea. In the Norwegian zone, the group has interest in the Frigg, Heimldal, Ekofisk, Valhall, Lille-Frigg, Froy, Oseberg, Hod, Sleipner East an Sleipner West Brage, Troll, Snorre, Statfjord East and Tordis production fields. (authors). 3 tabs., 1 photo

  16. Mineralogical and geochemical characteristics of the Noamundi-Koira basin iron ore deposits (India)

    Science.gov (United States)

    Mirza, Azimuddin; Alvi, Shabbar Habib; Ilbeyli, Nurdane

    2015-04-01

    India is one of the richest sources of iron ore deposits in the world; and one of them is located in the Noamundi-Koira basin, Singhbhum-Orissa craton. The geological comparative studies of banded iron formation (BIF) and associated iron ores of Noamundi-Koira iron ore deposits, belonging to the iron ore group in eastern India, focus on the study of mineralogy and major elemental compositions along with the geological evaluation of different iron ores. The basement of the Singhbhum-Orissa craton is metasedimentary rocks which can be traced in a broadly elliptical pattern of granitoids, surrounded by metasediments and metavolcanics of Greenstone Belt association. The Singhbhum granitoid is intrusive into these old rocks and to younger, mid Archaean metasediments, including iron formations, schists and metaquartzites and siliciclastics of the Precambrian Iron Ore Group (Saha et al., 1994; Sharma, 1994). The iron ore of Noamundi-Koira can be divided into seven categories (Van Schalkwyk and Beukes 1986). They are massive, hard laminated, soft laminated, martite-goethite, powdery blue dust and lateritic ore. Although it is more or less accepted that the parent rock of iron ore is banded hematite jasper (BHJ), the presence of disseminated martite in BHJ suggests that the magnetite of protore was converted to martite. In the study area, possible genesis of high-grade hematite ore could have occurred in two steps. In the first stage, shallow, meteoric fluids affect primary, unaltered BIF by simultaneously oxidizing magnetite to martite and replacing quartz with hydrous iron oxides. In the second stage of supergene processes, deep burial upgrades the hydrous iron oxides to microplaty hematite. Removal of silica from BIF and successive precipitation of iron resulted in the formation of martite- goethite ore. Soft laminated ores were formed where precipitation of iron was partial or absent. The leached out space remains with time and the interstitial space is generally filled

  17. Study on the determination of ore-formation age of primary gold ore

    International Nuclear Information System (INIS)

    Ying Junlong; Zhao Puyun; Guo Hong

    1997-01-01

    The accurate determination of gold ore-formation age and ore-source isotope composition are of important significance in the research on gold geology and prospecting. According to the summary of three year indoor and field work, the ore-formation ages and isotope compositions of some typical gold deposits were obtained: The age of gold ore of the Wuhuaaobao deposit in geo-syncline region north to the north margin of North-China paleo-land is 130-120 Ma corresponding to the Late-orogenic stage. The ore-formation age of the Saiwusu gold deposit in the southern platform region is 211 +- 15 Ma, recycling reworking of the old-land. The Hougou-Huangtuliang gold deposit located in the middle of the platform region is 243 +- 7 Ma old attributed to the regeneration ore-formation on the old-land. the age of Jiaojia-Rushan gold deposit in Eastern Shandong is 122.7 +- 3.4 Ma and 128 +- 23 Ma belonging to Yanshanian stage. The Babaoshan gold-silver deposit in Cathaysian old-land is 140 +- 5 Ma old originated from volcanic hydrothermal ore-formation

  18. Distribution and Multivariate Pollution Risks Assessment of Heavy Metals and Natural Radionuclides Around Abandoned Iron-Ore Mines in North Central Nigeria

    Science.gov (United States)

    Isinkaye, Omoniyi Matthew

    2018-02-01

    The Itakpe abandoned iron-ore mines constitute the largest iron-ore deposits in Nigeria with an estimated reserve of about three million metric tons of ore. The present effort is a part of a comprehensive study to estimate the environmental and radiological health hazards associated with previous mining operations in the study area. In this regard, heavy metals (Fe, Zn, Cu, Cd, Cr, Mn, Pb, Ni, Co and As) and natural radionuclides (U, Th and K) were measured in rock, soil and water samples collected at different locations within the mining sites. Atomic absorption and gamma-ray spectrometry were utilized for the measurements. Fe, Mn, Zn, Cu, Ni, Cd, Cr, Co Pb and As were detected at varying concentrations in rock and soil samples. Cd, Cr, Pb and As were not detected in water samples. The concentrations of heavy metals vary according to the following pattern; rock ˃ soil ˃ water. The mean elemental concentrations of K, U and Th are 2.9%, 0.8 and 1.2 ppm and 1.3%, 0.7 and 1.7 ppm, respectively, for rock and soil samples. Pearson correlation analyses of the results indicate that the heavy metals are mostly negatively correlated with natural radionuclides in the study area. Cancer and non-cancer risks due to heavy metals and radiological hazards due to natural radionuclides to the population living within the vicinity of the abandoned mines are lower than acceptable limits. It can, therefore, be concluded that no significant environmental or radiological health hazard is envisaged.

  19. Sedimentary carbonate-hosted giant Bayan Obo REE-Fe-Nb ore deposit of Inner Mongolia, China; a cornerstone example for giant polymetallic ore deposits of hydrothermal origin

    Science.gov (United States)

    Chao, E.C.T.; Back, J.M.; Minkin, J.A.; Tatsumoto, M.; Junwen, Wang; Conrad, J.E.; McKee, E.H.; Zonglin, Hou; Qingrun, Meng; Shengguang, Huang

    1997-01-01

    Detailed, integrative field and laboratory studies of the textures, structures, chemical characteristics, and isotopically determined ages and signatures of mineralization of the Bayan Obo deposit provided evidence for the origin and characteristics favorable for its formation and parameters necessary for defining giant polymetallic deposits of hydrothermal origin. Bayan Obo is an epigenetic, metasomatic, hydrothermal rare earth element (REE)-Fe-Nb ore deposit that is hosted in the metasedimentary H8 dolostone marble of the Middle Proterozoic Bayan Obo Group. The metasedimentary sequence was deposited on the northern continental slope of the North China craton. The mine area is about 100 km south of the suture marking Caledonian subduction of the Mongolian oceanic plate from the north beneath the North China craton. The mineralogy of the deposit is very complex, consisting of more than 120 different minerals, some of which are epigenetic minerals introduced by hydrothermal solutions, and some of which are primary and secondary metamorphic minerals. The major REE minerals are monazite and bastnaesite, whereas magnetite and hematite are the dominant Fe-ore minerals, and columbite is the most abundant Nb mineral. Dolomite, alkali amphibole, fluorite, barite, aegirine augite, apatite, phlogopite, albite, and microcline are the most widespread gangue minerals. Three general types of ores occur at Bayan Obo: disseminated, banded, and massive ores. Broad zoning of these ore types occurs in the Main and East Orebodies. Disseminated ores are in the outermost zone, banded ores are in the intermediate zone, and massive ores are in the cores of the orebodies. On the basis of field relations, host rocks, textures, structures, and mineral assemblages, many varieties of these three types of ores have been recognized and mapped. Isotopic dating of monazite, bastnaesite, aeschynite, and metamorphic and metasomatic alkali amphiboles associated with the deposit provides constraints

  20. Confidence- and security-building in North-East Asia. Working group I

    International Nuclear Information System (INIS)

    Cotton, J.

    1991-01-01

    In the discussions in Working Group I there were two general preoccupations which prevailed throughout the consideration of questions relating to North-East Asian confidence and security building: how much could North-East Asia learn from the European experience in Confidence Building measures, and could any of the underlying factors- economic, political and social which has moved Europe towards military and security accommodation be seen to work also in the Asia-Pacific region. The problem of North Korea is underlined in view of non acceptance of the IAEA safeguards regime although it had entered into multilateral set of obligations with other signatories by assenting the Non-proliferation Treaty

  1. North Wales Group report on the effects of the Chernobyl accident

    International Nuclear Information System (INIS)

    1987-11-01

    A report is presented by the North Wales Group concerning the sequence of events affecting North Wales and the identification of the residual problems following contamination from the Chernobyl accident. The first part of the report attempts to establish a time scale for radiation restrictions applicable in North Wales and the size of the areas which are involved. Part two deals with national arrangements to handle incidents like Chernobyl and examines the wider field of international arrangements. A review is given of events as seen by the affected community following the Chernobyl accident. (U.K.)

  2. North American Wood Waste Forum: Summary of Group Feedback, 2-3, 2012

    Science.gov (United States)

    Bob Falk

    2012-01-01

    This report summarizes the feedback and recommendations of the North American Wood Recovery Group. This report summarizes the barriers and opportunities in wood recovery, reuse, and recycling as identified by this group of stakeholders from the wood industry, waste industry, and relevant government agencies.

  3. Epidemic of Isothiazolinone Allergy in North America: Prevalence Data From the North American Contact Dermatitis Group, 2013-2014.

    Science.gov (United States)

    Zirwas, Matthew J; Hamann, Dathan; Warshaw, Erin M; Maibach, Howard I; Taylor, James S; Sasseville, Denis; DeKoven, Joel G; Fransway, Anthony F; Mathias, C G Toby; Zug, Kathryn A; DeLeo, Vincent A; Fowler, Joseph F; Marks, James G; Pratt, Melanie D; Belsito, Donald V

    Preservative sensitivity patterns evolve with changing use patterns in products. During the last decade, the use of methylisothiazolinone (MI) at higher concentrations in both leave-on and rinse-off products has significantly increased. This is the first North American Contact Dermatitis Group reporting cycle that includes both methylchloroisothiazolinone (MCI)/MI and MI data. The aim of this study was to report the prevalence of isothiazolinone allergy (MCI/MI and MI) in the North American Contact Dermatitis Group patch-test population from January 1, 2013, to December 31, 2014. At 13 centers in North America, 4860 patients were patch tested in a standardized manner with a series of 70 allergens, including MCI/MI 0.01% aqueous (aq) and MI 0.2% aq. Three hundred five patients (6.3%) had a positive reaction to MCI/MI; this is a significant increase from the previous cycle (5.0%, 2011-2012; P = 0.011). Five hundred twenty-one patients (10.7%) had a positive reaction to MI. These 2 isothiazolinones were among the most common preservative allergens in the 2013 to 2014 cycle; 11.9% of patch-tested individuals were allergic to 1 or both isothiazolinones. Individuals with MCI/MI and MI allergy were significantly more likely to have occupationally related skin disease (P dermatitis (P < 0.0001, P = 0.0474). The epidemic of isothiazolinone sensitivity documented in Europe is now in North America. Patch testing with only MCI/MI 0.01% aq will miss approximately half of isothiazolinone allergy cases, whereas testing with only MI 0.2% aq will miss approximately 10% of isothiazolinone allergy cases.

  4. 75 FR 76037 - HAVI Logistics, North America a Subsidiary of HAVI Group, LP Including On-Site Leased Workers of...

    Science.gov (United States)

    2010-12-07

    ... Logistics, North America a Subsidiary of HAVI Group, LP Including On-Site Leased Workers of Express Personnel Services and the La Salle Network, Bloomingdale, IL; Havi Logistics, North America, Lisle, IL..., applicable to workers of HAVI Logistics, North America, a subsidiary of HAVI Group, LP, including on-site...

  5. The actual status of uranium ore resources at Eko Remaja Sector: the need of verification of resources computation and geometrical form of mineralization zone by mining test

    International Nuclear Information System (INIS)

    Johan Baratha; Muljono, D.S.; Agus Sumaryanto; Handoko Supalal

    1996-01-01

    Uranium ore resources calculation was done after ending all of geological work step. Estimation process of ore resources was started from evaluation drilling, continued with borehole logging. From logging, the result has presented in anomaly graphs, then was processed to determine thickness and grade value of ore. Those mineralization points were correlated one another to form mineralization zones which have direction of N 270 degree to N 285 degree with 70 degree dip to North. From Grouping the mineralization distribution, 19 mineralization planes was constructed which contain 553 ton of U 3 O 8 measured. It is suggested that before expanding measured ore deposit area, mining test should be done first at certain mineralization planes to prove the method applied to calculate the reserve. Results form mining test could be very useful to reevaluate all the work-step done. (author); 4 refs; 2 tabs; 8 figs

  6. Radon risk in ore miners

    International Nuclear Information System (INIS)

    Beno, M.

    1997-01-01

    Underground workers are exposed to various clastogenic agents. One of these agents, radon, attracts attention of recent research as it causes lung cancer in the population occupationally exposed to its various concentrations especially in mine air of uranium mines or ore mines. This paper is a pilot study in which the numbers of chromosomal aberrations (CA) in lymphocytes of ore mines (Nizna Slana-iron ore, Hnusta-talc ore) located in east central Slovakia were followed and related to the lifetime underground radon exposure and to lifetime smoking. Seventy miners volunteering after an informed consent served as donors of venous blood. Twenty healthy pro-bands, age matched with the miners, which never worked underground (mostly clerks) served as donors of control blood samples. The exposure to radon and smoking has been estimated according to working-records and personal anamnesis. The findings unequivocally showed a small but statistically significant clastogenic effect of the exposure to underground environment of the mines concerned. This study has shown also a small but significant influence of smoking, which in the subgroup of miners working underground less than 1500 shifts may have acted synergically with the underground exposure. It was concluded tat: (1) Significantly higher counts of chromosomal aberrations in lymphocytes of 70 miners than in an age matched control group of 20 white-collar workers were found; (2) The higher counts of chromosomal aberrations could be ascribed to underground exposure of miners and to smoking; (3) The positive dependence of the number of chromosomal aberrations from the exposure to smoking was loose and it was expressed by significantly higher chromosomal aberrations counts in the group of miners working less than 1500 shifts underground; (4) A dependence of chromosomal aberrations counts from the exposure to radon could not be assessed. At relatively low numbers of pro-bands in subgroups it was not ruled out the confounding

  7. High resolution Rayleigh wave group velocity tomography in North-China from ambient seismic noise

    International Nuclear Information System (INIS)

    Fang Lihua; Wu Jianping; Ding Zhifeng; Panza, G.F.

    2009-03-01

    This study presents the results of the Rayleigh wave group velocity tomography in North-China performed using ambient seismic noise observed at 190 broadband and 10 very broadband stations of the North-China Seismic Array. All available vertical component time-series for the 14 months span between January, 2007 and February, 2008 are cross-correlated to obtain empirical Rayleigh wave Green functions that are subsequently processed, with the multiple filter method, to isolate the group velocity dispersion curves of the fundamental mode of Rayleigh wave. Tomographic maps, with a grid spacing of 0.25 deg. x 0.25 deg., are computed at the periods of 4.5s, 12s, 20s, 28s. The maps at short periods reveal an evident lateral heterogeneity in the crust of North-China, quite well in agreement with known geological and tectonic features. The North China Basin is imaged as a broad low velocity area, while the Taihangshan and Yanshan uplifts and Ordos block are imaged as high velocity zones, and the Quaternary intermountain basins show up as small low-velocity anomalies. The group velocity contours at 4.5s, 12s and 20s are consistent with the Bouguer gravity anomalies measured in the area of the Taihangshan fault, that cuts through the lower crust at least. Most of the historical strong earthquakes (M≥6.0) are located where the tomographic maps show zones with moderate velocity gradient. (author)

  8. Inhalation of uranium ores

    International Nuclear Information System (INIS)

    Stuart, B.O.; Jackson, P.O.

    1975-01-01

    In previous studies the biological dispositions of individual long-lived alpha members of the uranium chain ( 238 U, 234 U and 230 Th) were determined during and following repeated inhalation exposures of rats to pitchblende (26 percent U 3 O 8 ) ore. Although finely dispersed ore in secular equilibrium was inhaled, 230 Th/ 234 U radioactivity ratios in the lungs rose from 1.0 to 2.5 during 8 weeks of exposures and increased to 9.2 by four months after cessation of exposures. Marked non-equilibrium levels were also found in the tracheobronchial lymph nodes, kidneys, liver, and femur. Daily exposures of beagle dogs to high levels of this ore for 8 days resulted in lung 230 Th/ 234 U ratios of >2.0. Daily exposures of dogs to lower levels (0.1 mg/1) for 6 months, with sacrifice 15 months later, resulted in lung and thoracic lymph node 230 Th/ 234 U ratios ranging from 3.6 to 9 and nearly 7, respectively. The lungs of hamsters exposed to carnotite (4 percent U 3 O 8 ) ore in current lifespan studies show 230 Th/ 234 U ratios as high as 2.0 during daily inhalation of this ore in secular equilibrium. Beagle dogs sacrificed after several years of daily inhalations of the same carnotite ore plus radon daughters also showed marked non-equilibrium ratios of 230 Th/ 234 U, ranging from 5.6 to 7.4 in lungs and 6.2 to 9.1 in thoracic lymph nodes. This pattern of higher retention of 230 Th than 234 U in lungs, thoracic lymph nodes, and other tissues is thus consistent for two types of uranium ore among several species and suggests a reevaluation of maximum permissible air concentrations of ore, currently based only on uranium content

  9. 9th Annual Conference of the North East Polytechnics Mathematical Modelling & Computer Simulation Group

    CERN Document Server

    Bradley, R

    1987-01-01

    In recent years, mathematical modelling allied to computer simulation has emerged as en effective and invaluable design tool for industry and a discipline in its own right. This has been reflected in the popularity of the growing number of courses and conferences devoted to the area. The North East Polytechnics Mathematical Modelling and Computer Simulation Group has a balanced representation of academics and industrialists and, as a Group, has the objective of promoting a continuing partnership between the Polytechnics in the North East and local industry. Prior to the present conference the Group has organised eight conferences with a variety of themes related to mathematical modelling and computer simulation. The theme chosen for the Polymodel 9 Conference held in Newcastle upon Tyne in May 1986 was Industrial Vibration Modelling, which is particularly approp riate for 'Industry Year' and is an area which continues to present industry and academics with new and challenging problems. The aim of the Conferen...

  10. North Sea Scyphomedusae; summer distribution, estimated biomass and significance particularly for 0-group Gadoid fish

    Science.gov (United States)

    Hay, S. J.; Hislop, J. R. G.; Shanks, A. M.

    Data on the by-catch of Scyphomedusae from pelagic trawls was collected during the routine ICES International 0-group Gadoid Surveys of the North Sea, in June and July of the years 1971-1986 (except 1984). These data are used to describe the distributions, abundances and biomasses of three common North Sea Scyphomedusae: Aurelia aurita (L.), Cyanea capillata (L.) and C. lamarckii (Péron & Lesuer). Information is also presented on inter-annual variability, size (umbrella diameter) frequencies and, for the Cyanea species, umbrella diameter: wet weight relationships. The general role and ecological significance of Scyphomedusae is discussed and, given the well known 'shelter' relationships between Scyphomedusae and certain 0-group fish, whiting ( Merlangius merlangus) and haddock ( Melanogrammus aeglefinus), in particular. The data were examined for evidence of such relationships. Aurelia aurita, although fairly widespread in the northern North Sea was virtually absent from the central North Sea but very abundant in coastal waters. This species was particularly abundant off the Scottish east coast and especially in the Moray Firth. Cyanea lamerckii was most abundant in the southern and eastern North Sea. More widespread than Aurelia, this species was also most abundant in coastal regions, particularly off the Danish west coast. Cyanea capillata, with a more northern distribution was also more widely distributed and abundant offshore. This species was most abundant in the area between the Orkney/Shetland Isles and the Norwegian Deep and in shelf waters of the north west approaches to the North Sea. As with C. lamarckii it was also, in some years, abundant off the Scottish east coast and west of Denmark. The abundance and the size frequency of the jellyfish show considerable inter-annual variability, and variability between regions of the North Sea. It is considered that hydrographic variability and differences in food supply to both medusae and to their sessile

  11. Radioactivity in north European waters: report of Working Group 2 of CEC project MARINA

    International Nuclear Information System (INIS)

    Camplin, W.C.; Aarkrog, A.

    1989-01-01

    The primary objective of Working Group 2 of Project MARINA was to consider recent measurements of environmental radioactivity in north European waters and to use this, and other information, to report likely magnitude of doses to the critical group from marine pathways. The monitoring data were supplemented, where appropriate, with predictions from simple models. The major sources of radioactivity studied were as follows: (i) liquid wastes from nuclear fuel reprocessing plants, (Sellafield, Dounreay, Cap de la Hague); (ii) liquid wastes from nuclear power plants and other major nuclear industry sites, (including Belgium, Denmark, France, Finland, GDR, FDR, Netherlands, Sweden, UK, USSR); (iii) solid waste disposal in the deep north-east Atlantic; (iv) fallout from Chernobyl; and (v) naturally-occurring radionuclides. (author)

  12. 75 FR 38127 - Visteon Systems, LLC North Penn Plant Electronics Products Group Including On-Site Leased Workers...

    Science.gov (United States)

    2010-07-01

    ..., North Penn Plant, Electronics Products Group to be covered by this certification. The intent of the... North Penn Plant Electronics Products Group Including On-Site Leased Workers From Ryder Integrated... Certification Regarding Eligibility To Apply for Worker Adjustment Assistance and Alternative Trade Adjustment...

  13. Sampling of ore

    International Nuclear Information System (INIS)

    Boehme, R.C.; Nicholas, B.L.

    1987-01-01

    This invention relates to a method of an apparatus for ore sampling. The method includes the steps of periodically removing a sample of the output material of a sorting machine, weighing each sample so that each is of the same weight, measuring a characteristic such as the radioactivity, magnetivity or the like of each sample, subjecting at least an equal portion of each sample to chemical analysis to determine the mineral content of the sample and comparing the characteristic measurement with desired mineral content of the chemically analysed portion of the sample to determine the characteristic/mineral ratio of the sample. The apparatus includes an ore sample collector, a deflector for deflecting a sample of ore particles from the output of an ore sorter into the collector and means for moving the deflector from a first position in which it is clear of the particle path from the sorter to a second position in which it is in the particle path at predetermined time intervals and for predetermined time periods to deflect the sample particles into the collector. The apparatus conveniently includes an ore crusher for comminuting the sample particle, a sample hopper means for weighing the hopper, a detector in the hopper for measuring a characteristic such as radioactivity, magnetivity or the like of particles in the hopper, a discharge outlet from the hopper and means for feeding the particles from the collector to the crusher and then to the hopper

  14. Finding "safe" campuses: predicting the presence of LGBT student groups at North Carolina colleges and universities.

    Science.gov (United States)

    Kane, Melinda D

    2013-01-01

    A key indicator of a supportive campus climate for lesbian, gay, bisexual, and transgender (LGBT) college students is the existence of an LGBT student organization. This article integrates the research on high school LGBT policies and programs with social movement studies of campus activism to examine the characteristics associated with the existence of university-approved LGBT groups on North Carolina campuses. Drawing on data from the National Center for Education Statistics, campus Web sites, and other sources, logistic regression is used to examine the importance of public opinion, campus and community resources, and the institutional context in predicting the location of these student groups.

  15. Dd-antigen-antibody system in five caste groups in north India.

    Science.gov (United States)

    Berry, V; Kaur, H

    1991-12-01

    Antigen Dd, a polymorphic antigen found in extracts of certain human dandruff specimens, was investigated in five caste groups of north India. The incidence of antigen Dd-positive type varied from 21.21 per cent in Brahmins to 29.08 per cent in the Jat Sikhs of Punjab. However, a high frequency (45%) was observed in the Sunni Muslims of Kashmir, which differed significantly, when compared with different caste groups of Punjab. Family studies on 44 families indicated its inherited nature, the mode of inheritance being autosomal dominant.

  16. Introduction to ore geology

    International Nuclear Information System (INIS)

    Evans, A.M.

    1987-01-01

    This textbook on ore geology is for second and third year undergraduates and closely parallels the undergraduate course given in this subject at England's University of Leicester. The volume covers three major areas: (1) principles of ore geology, (2) examples of the most important types of ore deposits, and (3) mineralization in space and time. Many chapters have been thoroughly revised for this edition and a chapter on diamonds has been added. Chapters on greisen and pegmatite have also been added, the former in response to the changing situation in tin mining following the recent tin crisis, and the latter in response to suggestions from geologists in a number of overseas countries. Some chapters have been considerably expanded and new sections added, including disseminated gold deposits and unconformity-associated uranium deposits. The author also expands on the importance of viewing mineral deposits from an economic standpoint

  17. Wet Wipe Allergens: Retrospective Analysis From the North American Contact Dermatitis Group 2011-2014.

    Science.gov (United States)

    Warshaw, Erin M; Aschenbeck, Kelly A; Zug, Kathryn A; Belsito, Donald V; Zirwas, Matthew J; Fowler, Joseph F; Taylor, James S; Sasseville, Denis; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Maibach, Howard I; Mathias, C G Toby; DeKoven, Joel G

    Although there are several case reports of wet wipe-associated contact dermatitis, the prevalence of wipes as a source of allergic contact dermatitis in larger populations and the responsible allergens are largely unknown. The aim of the study was to determine the prevalence of wet wipes as a source of contact allergy and the most commonly associated allergens in a North American tertiary referral patch test population. Data collected from 2011 to 2014 by the North American Contact Dermatitis Group was used to conduct a retrospective cross-sectional analysis of patient demographics and patch test results associated with the triple-digit source code for "wet wipe." Of the 9037 patients patch tested during the study period, 79 (0.9%) had a positive patch test reaction to an allergen identified with a wet wipe source. The most commonly associated allergens were preservatives, including the following: methylisothiazolinone (MI) (59.0%), methylchloroisothiazolinone (MCI)/MI (35.6%), bronopol (2-bromo-2-nitropropane-1,3-diol) (27.4%), and iodopropynyl butylcarbamate (12.3%). Fragrance (combined) represented 12.3%. Anal/genital dermatitis was 15 times more likely (P contact allergy had their contact allergens detected by the North American Contact Dermatitis Group screening series. Wet wipes are an important source of contact allergy. Preservatives are the main allergens, especially isothiazolinones.

  18. Larval growth and drift pattern and the separation of herring spawning groups in the North Sea

    DEFF Research Database (Denmark)

    Munk, Peter; Christensen, Villy

    1990-01-01

    Data from two internationally co-ordinated survey programmes are used in an attempt to display the events in the early life that took place during the 'recovery period' of the North Sea herring stock, 1979-1986. During the period, an increasing importance of the spawning grounds off Buchan and off...... Yorkshire is evident from distributions of newly hatched herring larvae. The dramatic changes in relative importance of spawning grounds are traced in the data on both late larvae (6 months old) and juveniles (18 months old). The onset of extended spawning off Buchan and off Yorkshire was followed...... in the relative contributions from spawning grounds apparently influence the overall spatial distribution as well as size composition of larval and juvenile North Sea herring. The findings indicate that groups of larvae retain, to a large extent, separate distributions until metamorphosis, and point to larval...

  19. Disparities in universal prenatal screening for group B streptococcus--North Carolina, 2002-2003.

    Science.gov (United States)

    2005-07-22

    Group B streptococcus (GBS) is a leading cause of neonatal morbidity and mortality in the United States. Intrapartum antibiotics administered to women at risk for transmitting GBS to their newborns are effective in preventing perinatal GBS infection. In 2002, CDC, the American Academy of Pediatrics, and the American College of Obstetricians and Gynecologists recommended universal prenatal screening for vaginal and rectal GBS colonization at 35-37 weeks' gestation. To examine prenatal GBS screening among pregnant women in North Carolina, CDC analyzed 2002 and 2003 data from the North Carolina Pregnancy Risk Assessment Monitoring System (PRAMS). The proportions of women reporting prenatal screening for GBS were similar in 2002 and 2003 (70% and 74%, respectively); however, for both years, women of Hispanic ethnicity and women who received prenatal care at a hospital or health department clinic were less likely to report prenatal screening for GBS. These findings underscore the need to increase GBS-related education and prevention activities targeted to these populations.

  20. Patch-testing North American lip dermatitis patients: data from the North American Contact Dermatitis Group, 2001 to 2004.

    Science.gov (United States)

    Zug, Kathryn A; Kornik, Rachel; Belsito, Donald V; DeLeo, Vincent A; Fowler, Joseph F; Maibach, Howard I; Marks, James G; Mathias, C G Toby; Pratt, Melanie D; Rietschel, Robert L; Sasseville, Denis; Storrs, Frances J; Taylor, James S; Warshaw, Erin M

    2008-01-01

    The most common differential diagnoses for patients presenting with lip dermatitis or inflammation include atopic, allergic, and irritant contact dermatitis. Patch testing can be performed to identify the allergic contact conditions. To report North American Contact Dermatitis Group (NACDG) patch-test results of patients who presented for patch testing with only lip involvement from 2001 to 2004. Patient characteristics, allergen frequencies, relevance, final diagnoses, and relevant allergic sources not in the NACDG screening series were evaluated. The NACDG 2001-2004 database was used to select patients presenting with only lip involvement. Of 10,061 patients tested, 2% (n = 196) had lips as the sole involved site. Most (84.2%) were women. After patch testing, 38.3% (n = 75) were diagnosed with allergic contact cheilitis. Fragrance mix, Myroxilon pereirae, and nickel were the most common relevant allergens. Of 75 patients, 27 (36%) had relevant positive patch-test reactions to items not on the NACDG series; lipstick and cosmetics were the predominant sources. Patch testing is valuable in the evaluation and identification of contact allergy in patients referred for lip dermatitis. The use of supplementary allergens based on history and exposure is important in the identification of additional relevant allergens. Over a third of patients with contact allergy had other factors, such as irritant dermatitis, considered relevant to their condition.

  1. The North Seas Countries' Offshore Grid Initiative. Initial Findings. Final Report. Working Group 1 - Grid Configuration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-15

    This report focuses on the tasks and results from Working Group 1 (WG1), grid configuration and integration, chaired jointly by representatives from Denmark and the Netherlands. The methodology, assumptions concerning generation portfolio, load situation, available technology and results are presented. This report presents the WG1 Offshore Grid Study that supports the North Seas Countries' Offshore Grid Initiative (NSCOGI) final report. The information contained in this report aims to evaluate the long-term development of an offshore grid structure in the North Seas by providing a view on how such a grid may possibly develop in the future, based on the assumptions made for this study. The report aims to compare and evaluate the possible advantages and disadvantages of the long term development of an optimised, integrated (or meshed) offshore grid in the North Seas by providing a view of how that possible grid might develop in the future against changes to the electricity energy requirements. To evaluate basic variants, different transmission design topologies (radial and meshed) were compared and analysed with respect to various aspects, such as cost/benefits, import and export levels and the systems' CO2 emissions.

  2. Opportunity for natural selection among five population groups of Manipur, North East India.

    Science.gov (United States)

    Asghar, M; Meitei, S Y; Luxmi, Y; Achoubi, N; Meitei, K S; Murry, B; Sachdeva, M P; Saraswathy, K N

    2014-01-01

    Opportunity for natural selection among five population groups of Manipur in comparison with other North East Indian population has been studied. Crow's index as well as Johnston and Kensinger's index for natural selection were calculated based on differential fertility and mortality. The mortality component was found to be lower compared to fertility component in all the populations which may attribute to comparatively improved and easily accessible health care facilities. However, different selection pressures, artificial and natural, seem to be influencing the selection intensity through induced abortion and spontaneous abortion among the two non-tribal migrant groups: Bamon and Muslims, respectively. This study highlights the probable interaction of artificial and natural selection in determining the evolutionary fate of any population group.

  3. Lower Cretaceous Luscar group (revised) of the northern and north-central foothills of Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Langenberg, C W; McMechan, M E

    1985-03-01

    Lower Cretaceous coal-bearing strata exposed in the northern and north-central foothills of Alberta form part of a predominantly nonmarine succession that extends from Montana to northeastern British Columbia. The Luscar Group (revised) forms the sequence of coal bearing Lower Cretaceous strata that disconformably overlies marine and nonmarine strata of the Nikanassin Formation or Minnes Group and disconformably underlies marine shales of the Blackstone or Shaftesbury formations. It includes a thin, basal conglomerate, a predominantly nonmarine sandstone and shale unit that locally contains coal; a marine shale and sandstone unit, and an upper nonmarine sandstone and shale unit that contains thick commercial coal seams. These units form the Cadomin, Gladstone, Moosebar and Gates formations, respectively. The Luscar Group is exposed from Kakwa River to Clearwater River in the Foothills of Alberta. It represents a slight modification, by the inclusion of the thin basal conglomerate, from the previous usage of the term Luscar in the northern Foothills of Alberta. 25 references.

  4. Ore potential of basic rocks in Finland

    International Nuclear Information System (INIS)

    Reino, J.; Ekberg, M.; Heinonen, P.; Karppanen, T.; Hakapaeae, A.; Sandberg, E.

    1993-02-01

    The report is associated with a study programme on basic rocks, which has the aim to complement the preliminary site investigations on repository for TVO's (Teollisuuden Voima Oy) spent nuclear fuel. The report comprises a mining enterprise's view of the ore potential of basic plutonic rocks in Finland. The ores associated with basic plutonic rocks are globally known and constitute a significant share of the global mining industry. The ores comprise chromium, vanadium-titanium-iron, nickel-copper and platinum group element ores. The resources of the metals in question and their mining industry are examined globally. A review of the use of these metals in the industry is presented as well. General factors affecting the mining industry, such as metal prices, political conjunctures, transport facilities, environmental requirements and raw material sources for the Finnish smelters have been observed from the point of view of their future effect on exploration activity and industrial development in Finland. Information on ores and mineralizations associated with Finnish basic rocks have been compiled in the report. The file comprises 4 chromium occurrences, 8 vanadium-titanium-iron occurrences, 13 PGE occurrences and 38 nickel-copper occurrences

  5. Geological exploration of uranium ores at Burgos' basin

    International Nuclear Information System (INIS)

    Cabrera Valdez, M.E.

    1975-01-01

    The outcrop sediments of the Burgos river basin cover the complete Cenozoic sequence from the Pallaeocene to recent date, and are arranged in the form of parallel strips with a regional dip towards the east, in which direction the sediments become steadily younger. Generally speaking they correspond to a regressive process the lithology of which is an alternation of shales, sandstones, tuffaceous material and conglomerates. The explorations and evaluations of sedimentary uranium deposits so far carried out in the north-east of Mexico show close relationships between the mineralization and the sedimentary processes of the enclosing rock. Analysis of the sedimentary-type uranium ore bodies in Mexico indicates characteristics very similar to those found in the deposits of the same type which were first studied and described in southern Texas and were used as a standard for the first exploratory studies. The uranium ore in the State of Texas is found in sands belonging mainly to the Jackson group of the Eocene and, to a lesser extent, the Catahoula formation of Miocene-Oligocene age. In the Burgos basin the existence of uranium deposits in the non-marine Frio formation of Oligocene age, with geological characteristics similar to the Texan deposits, has been demonstrated. This comparative analysis suggests very good prospects for uranium exploration in the region; it is recommended that priority be given to intensive study of the sediments of the non-marine member of the Frio formation, and the Jackson and Catahoula formations. (author)

  6. Hydrogen Reduction of Hematite Ore Fines to Magnetite Ore Fines at Low Temperatures

    Directory of Open Access Journals (Sweden)

    Wenguang Du

    2017-01-01

    Full Text Available Surplus coke oven gases (COGs and low grade hematite ores are abundant in Shanxi, China. Our group proposes a new process that could simultaneously enrich CH4 from COG and produce separated magnetite from low grade hematite. In this work, low-temperature hydrogen reduction of hematite ore fines was performed in a fixed-bed reactor with a stirring apparatus, and a laboratory Davis magnetic tube was used for the magnetic separation of the resulting magnetite ore fines. The properties of the raw hematite ore, reduced products, and magnetic concentrate were analyzed and characterized by a chemical analysis method, X-ray diffraction, optical microscopy, and scanning electron microscopy. The experimental results indicated that, at temperatures lower than 400°C, the rate of reduction of the hematite ore fines was controlled by the interfacial reaction on the core surface. However, at temperatures higher than 450°C, the reaction was controlled by product layer diffusion. With increasing reduction temperature, the average utilization of hydrogen initially increased and tended to a constant value thereafter. The conversion of Fe2O3 in the hematite ore played an important role in the total iron recovery and grade of the concentrate. The grade of the concentrate decreased, whereas the total iron recovery increased with the increasing Fe2O3 conversion.

  7. Radioactivity in north European waters: report of Working Group 2 of CEC project MARINA

    Energy Technology Data Exchange (ETDEWEB)

    Camplin, W C [Ministry of Agriculture, Fisheries and Food, Lowestoft (UK). Directorate of Fisheries Research; Aarkrog, A [Risoe National Lab., Roskilde (Denmark)

    1989-01-01

    The primary objective of Working Group 2 of Project MARINA was to consider recent measurements of environmental radioactivity in north European waters and to use this, and other information, to report the likely magnitude of doses to the critical group from marine pathways. The monitoring data were supplemented, where appropriate, with predictions from simple models. The major sources of radioactivity studied were as follows: (i) liquid wastes from nuclear fuel reprocessing plants; (ii) liquid wastes from nuclear power plants and other major nuclear industry sites; (iii) solid waste disposal in the deep north-east Atlantic; (iv) fallout from Chernobyl; and (v) naturally-occurring radionuclides. Some of the largest doses from marine pathways are predicted for naturally-occurring radionuclides. In this case, the dominant radionuclide is polonium-210 and the dominant pathway is via consumption of molluscan species. The highest doses from the nuclear industry were due to the operation of the reprocessing plant at Sellafield. Discharges from this site have been decreasing substantially in recent years and, as a consequence, doses have also been reducing. (author).

  8. Geochemistry and ore prospecting

    International Nuclear Information System (INIS)

    Le Caignec, R.

    1954-01-01

    Applied geochemistry is a new technique which helps the geologist in detecting ore deposits. Some deposits, even when they are covered with rather thick surface structures, form around these zones where the infinitesimal content of some elements of soils or waters is notably different. These 'anomalies' may be contemporaneous to the deposit-structure (primary dispersion) or may have occurred later (secondary dispersion). Various factors rule these anomalies: ore-stability, soil homogeneity, water conditions, topography, vegetation, etc... Applied geochemistry is in fact the study of analysis techniques of metal traces in soils as well as the geological interpretation of observed anomalies. This report gives practical data on sampling methods, yields, costs and also on special problems of uranium geochemistry. (author) [fr

  9. The genesis of ores

    International Nuclear Information System (INIS)

    Brimhall, G.

    1991-01-01

    Human history and technology have been shaped by metals. How did they become concentrated in minable deposits located so conveniently near the earth's surface? The author explains the mechanisms of fluid transport-by magma, water and even air and wind-responsible for the chemical and physical interactions that created bodies of metallic ores throughout geologic history. From their formation to their modification at the surface of the earth, ore deposits are geologically transitory and reflect dynamic processes within the earth as well as atmospheric and climatic influences on hydrologic systems. As highly reactive supracrustal systems, they then serve as geochemical sensors providing a powerful record and set of tracer elements for deducing the history, transport paths and forces operative in the crust

  10. Computer finds ore

    Science.gov (United States)

    Bell, Peter M.

    Artificial intelligence techniques are being used for the first time to evaluate geophysical, geochemical, and geologic data and theory in order to locate ore deposits. After several years of development, an intelligent computer code has been formulated and applied to the Mount Tolman area in Washington state. In a project funded by the United States Geological Survey and the National Science Foundation a set of computer programs, under the general title Prospector, was used successfully to locate a previously unknown ore-grade porphyry molybdenum deposit in the vicinity of Mount Tolman (Science, Sept. 3, 1982).The general area of the deposit had been known to contain exposures of porphyry mineralization. Between 1964 and 1978, exploration surveys had been run by the Bear Creek Mining Company, and later exploration was done in the area by the Amax Corporation. Some of the geophysical data and geochemical and other prospecting surveys were incorporated into the programs, and mine exploration specialists contributed to a set of rules for Prospector. The rules were encoded as ‘inference networks’ to form the ‘expert system’ on which the artificial intelligence codes were based. The molybdenum ore deposit discovered by the test is large, located subsurface, and has an areal extent of more than 18 km2.

  11. Genetic differentiation and population structure of five ethnic groups of Punjab (North-West India).

    Science.gov (United States)

    Singh, Gagandeep; Talwar, Indu; Sharma, Rubina; Matharoo, Kawaljit; Bhanwer, A J S

    2016-12-01

    The state of Punjab in the North-West part of India has acted as the main passage for all the major human invasions into the Indian subcontinent. It has resulted in the mixing of foreign gene pool into the local populations, which led to an extensive range of genetic diversity and has influenced the genetic structure of populations in Punjab, North-West India. The present study was conducted to examine the genetic structure, relationships, and extent of genetic differentiation in five Indo-European speaking ethnic groups of Punjab. A total of 1021 unrelated samples belonging to Banias, Brahmins, Jat Sikhs, Khatris, and Scheduled castes were analyzed for four human-specific Ins/Del polymorphic loci (ACE, APO, PLAT, and D1) and three restriction fragment length polymorphisms ESR (PvuII), LPL (PvuII), and T2 (MspI) using Polymerase chain reaction (PCR). All the loci were found to be polymorphic among the studied populations. The frequency of the Alu insertion at APO locus was observed to exhibit the highest value (82.6-96.3 %), whereas D1 exhibited the lowest (26.5-45.6 %) among all the ethnic groups. The average heterozygosity among the studied populations ranged from 0.3816 in Banias to 0.4163 in Khatris. The F ST values ranged from 0.0418 to 0.0033 for the PLAT and LPL loci, respectively, with an average value being 0.0166. Phylogenetic analysis revealed that Banias and Khatris are genetically closest to each other. The Jat Sikhs are genetically close to Brahmins and are distant from the Banias. The Jat Sikhs, Banias, Brahmins, and Khatris are genetically very distant from the Scheduled castes. Overall, Uniform allele frequency distribution patterns, high average heterozygosity values, and a small degree of genetic differentiation in this study suggest a genetic proximity among the selected populations. A low level of genetic differentiation was observed in the studied population groups indicating that genetic drift might have been small or negligible in shaping

  12. Risk management of radiation therapy. Survey by north Japan radiation therapy oncology group

    International Nuclear Information System (INIS)

    Aoki, Masahiko; Abe, Yoshinao; Yamada, Shogo; Hareyama, Masato; Nakamura, Ryuji; Sugita, Tadashi; Miyano, Takashi

    2004-01-01

    A North Japan Radiation Oncology Group (NJRTOG) survey was carried out to disclose the risk management of radiation therapy. During April 2002, we sent questionnaires to radiation therapy facilities in northern Japan. There were 31 replies from 27 facilities. Many incidents and accidents were reported, including old cases. Although 60% of facilities had a risk management manual and/or risk manager, only 20% had risk management manuals for radiation therapy. Eighty five percent of radiation oncologists thought that incidents may be due to a lack of manpower. Ninety percent of radiation oncologists want to know the type of cases happened in other facilities. The risk management system is still insufficient for radiation therapy. We hope that our data will be a great help to develop risk management strategies for radiation therapy for all radiation oncologists in Japan. (author)

  13. Studies on uranium ore processing

    International Nuclear Information System (INIS)

    Kim, C.H.; Park, S.W.; Lim, J.K.; Chung, M.K.

    1981-01-01

    Chemical and chemical engineering techniques of the uranium ore processing established by France COGEMA (Compagnie Generale des Matieres Nucleaires) have been comprehensively reviewed in preparation for successful test operation of the pilot plant to be completed by the end of 1981. It was found that the amount of sulfuric acid (75 Kg/t, ore) and sodium chlorate (2.5 Kg/t, ore) recommended by COGEMA should be increased up to 100 Kg/t, ore and 10 Kg/t, ore respectively to obtain satisfactory leach of uranium for some ore samples produced at the different pits of Goesan uranium mine. Conditions of the other processes such as solvent extraction, stripping, and precipitation of yellow cake were generally agreed with the results of intensive studies done by this laboratory

  14. Patch testing in children from 2005 to 2012: results from the North American contact dermatitis group.

    Science.gov (United States)

    Zug, Kathryn A; Pham, Anh Khoa; Belsito, Donald V; DeKoven, Joel G; DeLeo, Vincent A; Fowler, Joseph F; Fransway, Anthony F; Maibach, Howard I; Marks, James G; Mathias, C G Toby; Pratt, Melanie D; Sasseville, Denis; Storrs, Frances J; Taylor, James S; Warshaw, Erin M; Zirwas, Matthew J

    2014-01-01

    Allergic contact dermatitis is common in children. Epicutaneous patch testing is an important tool for identifying responsible allergens. The objective of this study was to provide the patch test results from children (aged ≤18 years) examined by the North American Contact Dermatitis Group from 2005 to 2012. This is a retrospective analysis of children patch-tested with the North American Contact Dermatitis Group 65- or 70-allergen series. Frequencies and counts were compared with previously published data (2001-2004) using χ statistics. A total of 883 children were tested during the study period. A percentage of 62.3% had ≥1 positive patch test and 56.7% had ≥1 relevant positive patch test. Frequencies of positive patch test and relevant positive patch test reaction were highest with nickel sulfate (28.1/25.6), cobalt chloride (12.3/9.1), neomycin sulfate (7.1/6.6), balsam of Peru (5.7/5.5), and lanolin alcohol 50% petrolatum vehicle (5.5/5.1). The ≥1 positive patch test and ≥1 relevant positive patch test in the children did not differ significantly from adults (≥19 years) or from previously tested children (2001-2004). The percentage of clinically relevant positive patch tests for 27 allergens differed significantly between the children and adults. A total of 23.6% of children had a relevant positive reaction to at least 1 supplemental allergen. Differences in positive patch test and relevant positive patch test frequencies between children and adults as well as test periods confirm the importance of reporting periodic updates of patch testing in children to enhance clinicians' vigilance to clinically important allergens.

  15. Complexing and hydrothermal ore deposition

    CERN Document Server

    Helgeson, Harold C

    1964-01-01

    Complexing and Hydrothermal Ore Deposition provides a synthesis of fact, theory, and interpretative speculation on hydrothermal ore-forming solutions. This book summarizes information and theory of the internal chemistry of aqueous electrolyte solutions accumulated in previous years. The scope of the discussion is limited to those aspects of particular interest to the geologist working on the problem of hydrothermal ore genesis. Wherever feasible, fundamental principles are reviewed. Portions of this text are devoted to calculations of specific hydrothermal equilibriums in multicompone

  16. China's emergence as the world's leading iron-ore-consuming country

    Science.gov (United States)

    Kirk, W.S.

    2004-01-01

    China has become the leading iron ore consuming nation, and, based on recent steel production capacity increases and plans for more, its consumption will almost certainly to continue to grow. China's iron ore industry, however, faces a number of problems. China's iron ore is low-grade, expensive to process, and its mines are being depleted. For many Chinese steelmakers, particularly in the coastal regions, the delivered cost of domestic iron ore, is more than the delivered cost of foreign ore. Thus China's iron ore imports are expected to increase. As China's growth continues, it will almost certainly surpass Japan to become the leading iron ore importing country as well. Without China's increasing appetite for iron ore, the world iron ore market would be flat or declining. China's recent imports largely offset the slump in demand in North America and Europe. China is regarded by the iron ore industry as the growth sector for the next decade. Although Chinese imports are expected to continue their rapid increase and imports in other Asian countries are expected to continue growing, there appears to be enough greenfield and expansion projects to meet future demand for iron ore worldwide. Present suppliers of iron ore, Australia, Brazil, India, and South Africa, will probably be the chief beneficiaries of China's increasing consumption of iron ore. How long China can continue its extraordinary growth is the primary issue for the future of the iron ore industry. Based on the number and size of planned blast furnaces it appears that China's growth could continue for several more years. ?? 2004 Taylor and Francis.

  17. Functional groups in North Chilean desert shrub species, based on the water sources used

    International Nuclear Information System (INIS)

    Squeo, Francisco A; Olivares, Nancy; Olivares, Sandra; Jorquera, Carmen; Pollastri, Alberto; Aguirre, Evelyn; Aravena, Ramon; Ehleringer, James R

    1999-01-01

    Primary productivity and vegetation structure in arid ecosystems are determined by water availability. In studies conducted in the coastal dry land of North Central Chile (29 degrees 43'S; 71degrees 14'0, 300m), the mechanisms to use different water sources by shrubs species, in two contrasting rainfall years were compared. Information on pheno logical studies, root architecture and water sources used by shrubs through the use of stable isotopes is are discussed. Six functional groups based on water uptake and water use are recognized. The functional groups were defined based on their habits (deciduous and evergreen), their root systems, (shallow, dimorphic and deep), and their ability to use different water sources (surficial and/or deep). Because of the differential impact of the goat overgrazing on different functional groups, this would result on a lower utilization of surficial waters. A management and/or restoration plan should maximize the use of all water sources available to recover the primary productivity and the system stability

  18. Population structure and group composition of western lowland gorillas in north-western Republic of Congo.

    Science.gov (United States)

    Magliocca, F; Querouil, S; Gautier-Hion, A

    1999-01-01

    Population studies are an essential part of conservation actions. Under exceptional observation conditions we studied a western lowland gorilla population visiting the Maya salt-clearing (north of the Parc national d'Odzala, P.N.O., Congo) over an 8 month period; 36 groups and 18 solitary individuals (a total of 420 individuals) have been identified visiting the clearing, which suggests a high gorilla density in the region. Ninety-six percent of the gorillas entered the clearing in groups. One-male groups had a mean size of 11.2. Ninety percent of solitary individuals were silver-back males. Compared with other populations of both lowland gorillas and mountain gorillas, the Maya population had the highest immature rate and the highest number of infants per female. Ecological correlates that could explain the attractiveness of the Maya clearing are discussed. The present status and the renewal rate of the Maya population indicate the need for further studies and confirm the importance of developing eco-tourism in this region as part of the sustainable park management activities developed by the ECOFAC programme (European Union). The results also provide arguments to support the proposal for extending the P.N.O. to include this region, which is rich in salt-clearings and attracts many other key-species of mammal such as forest elephants.

  19. Zeolitization at uranium ore manifestation

    International Nuclear Information System (INIS)

    Petrosyan, R.V.; Buntikova, A.F.

    1981-01-01

    The process of zeolitization at uranium ore manifestation is studied. A specific type of low-temperature wall endogenous alteration of rocks due to the effect of primary acid solution with low content of carbonic acid is established. Leaching of calcium from enclosing rocks and its deposition in ore-accompanying calcium zeolites is a characteristic feature of wall-metasomatosis. Formation of desmin- calcite-laumontite and quartz-fluoroapatite of vein associations, including ore minerals (uranophane and metaotenite), is genetically connected with calcium metasomatosis. On the basis of the connection of ore minerals with endogeneous process of zeolitization a conclusion can be made on endogenous origin of uranophane and metaotenite [ru

  20. Geology and ore deposits of the Pioche district, Nevada

    Science.gov (United States)

    Westgate, L.G.; Knopf, Adolph

    1932-01-01

    LOCATION AND SURFACE FEATURES The Bristol Range, Highland, and Ely Range quadrangles make up the larger part of a. rectangular area 35 miles north and south by 24 miles east and west, which lies 19 miles west of the Nevada-Utah line and about 250 miles southwest of Salt Lake City. The district lies within the Great Basin, a semiarid region of alternating mountain ranges and intermontane plains floored largely by outwash from the mountains. The plain, which slopes away from the ranges, stands between 4,700 and 6,000 feet above the sea. The Bristol and Highland Ranges, which are separated only by a low gap, form an almost continuous north-south range that rises about 2,500 feet above the highest part of the surrounding plain, to general altitudes of 8,000 to 9,000 feet, though the highest point, Highland Peak, reaches 9,395 feet. A lower range, the Ely Range, with a northwesterly trend, lies farther east and nearly in touch with the Bristol-Highland Range. The town of Pioche lies midway on the. eastern foot of the Ely Range. ROOKS OF THE PIOOHB REGION The rocks of the ranges are Paleozoic sediments, Tertiary (?) lavas and intrusive rocks, and Pliocene (?) tuffs. The Paleozoic sediments have a total thickness of nearly 18,000 feet. Over 8,000 feet of the Cambrian has been measured without reaching its base. The lowest Cambrian formation is a quartzite, of which only the upper 1,500 feet is exposed, and this is followed by 1,200 feet of shale, 400 feet of limestone, aoid 150 feet of shale. Above this second shale the upper three-fourths of the Cambrian consists of limestone and dolomitic limestone. It is in the quartzite and in the limestone interbedded in and bounding the shales that the main ore bodies of the district have been found. Above the Cambrian comes 1,795 feet of Ordovician limestone, with some interbedded dolomite and with a 50-foot quartzite a, third of the way down from the top; 75 feet of Silurian dolomite; 3,000 feet of Middle Devonian dolomite with

  1. Uranium ore deposits

    International Nuclear Information System (INIS)

    Angelelli, Victorio.

    1984-01-01

    The main uranium deposits and occurrences in the Argentine Republic are described, considering, in principle, their geologic setting, the kind of 'model' of the mineralization and its possible origin, and describing the ore species present in each case. The main uraniferous accumulations of the country include the models of 'sandstong type', veintype and impregnation type. There are also other kinds of accumulations, as in calcrete, etc. The main uranium production has been registered in the provinces of Mendoza, Salta, La Rioja, Chubut, Cordoba and San Luis. In each case, the minerals present are mentioned, having been recognized 37 different species all over the country (M.E.L.) [es

  2. Niobium ore OKA-1

    International Nuclear Information System (INIS)

    Steger, H.F.; Bowman, W.S.

    1981-01-01

    A 287-kg sample of a niobium ore, OKA-1, from Oka, Quebec, was prepared as a compositional reference material. OKA-1 was ground to minus 74 μm, blended in one lot, tested for homogeneity by X-ray fluorescence and chemical methods and bottled in 200-g units. In a 'free-choice' round-robin analytical program, 22 laboratories contributed results for niobium in each of two bottles of OKA-1. A statistical analysis of the data gave a recommended value of 0.37 +- 0.01% for niobium

  3. Mortality among sulfide ore miners

    International Nuclear Information System (INIS)

    Ahlman, K.; Koskela, R.S.; Kuikka, P.; Koponen, M.; Annanmaeki, M.

    1991-01-01

    Lung cancer mortality was studied during 1965-1985 in Outokumpu township in North Karelia, where an old copper mine was located. Age-specific lung cancer death rates (1968-1985) were higher among the male population of Outokumpu than among the North Karelian male population of the same age excluding the Outokumpu district (p less than .01). Of all 106 persons who died from lung cancer during 1965-1985 in Outokumpu township, 47 were miners of the old mine, 39 of whom had worked there for at least three years and been heavily exposed to radon daughters and silica dust. The study cohort consisted of 597 miners first employed between 1954 and 1973 by a new copper mine and a zinc mine, and employed there for at least 3 years. The period of follow-up was 1954-1986. The number of person-years was 14,782. The total number of deaths was 102; the expected number was 72.8 based on the general male population and 97.8 based on the mortality of the male population of North Karelia. The excess mortality among miners was due mainly to ischemic heart disease (IHD); 44 were observed, the expected number was 22.1, based on the general male population, and the North Karelian expected number was 31.2 (p less than .05). Of the 44 miners who died from IHD, 20 were drillers or chargers exposed to nitroglycerin in dynamite charges, but also to several simultaneous stress factors including PAHs, noise, vibration, heavy work, accident risk, and working alone. Altogether 16 tumors were observed in the cohort. Ten of these were lung cancers, the expected number being 4.3. Miners who had died from lung cancer were 35-64 years old, and had entered mining work between 1954 and 1960. Five of the ten lung cancer cases came from the zinc mine (1.7 expected). Three of them were conductors of diesel-powered ore trains

  4. North American Contact Dermatitis Group patch test results: 2009 to 2010.

    Science.gov (United States)

    Warshaw, Erin M; Belsito, Donald V; Taylor, James S; Sasseville, Denis; DeKoven, Joel G; Zirwas, Matthew J; Fransway, Anthony F; Mathias, C G Toby; Zug, Kathryn A; DeLeo, Vincent A; Fowler, Joseph F; Marks, James G; Pratt, Melanie D; Storrs, Frances J; Maibach, Howard I

    2013-01-01

    Patch testing is an important diagnostic tool for determination of substances responsible for allergic contact dermatitis. This study reports the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2009, to December 31, 2010. At 12 centers in North America, patients were tested in a standardized manner with a screening series of 70 allergens. Data were manually verified and entered into a central database. Descriptive frequencies were calculated, and trends were analyzed using χ2 statistics. A total of 4308 patients were tested. Of these, 2614 (60.7%) had at least 1 positive reaction, and 2284 (46.3%) were ultimately determined to have a primary diagnosis of allergic contact dermatitis. Four hundred twenty-seven (9.9%) patients had occupationally related skin disease. There were 6855 positive allergic reactions. As compared with the previous reporting period (2007-2008), the positive reaction rates statistically decreased for 20 allergens (nickel, neomycin, Myroxylon pereirae, cobalt, formaldehyde, quaternium 15, methydibromoglutaronitrile/phenoxyethanol, methylchlorisothiazolinone/methylisothiazolinone, potassium dichromate, diazolidinyl urea, propolis, dimethylol dimethylhydantoin, 2-bromo-2-nitro-1,3-propanediol, methyl methacrylate, ethyl acrylate, glyceryl thioglycolate, dibucaine, amidoamine, clobetasol, and dimethyloldihydroxyethyleneurea; P < 0.05) and statistically increased for 4 allergens (fragrance mix II, iodopropynyl butylcarbamate, propylene glycol, and benzocaine; P < 0.05). Approximately one quarter of tested patients had at least 1 relevant allergic reaction to a non-NACDG allergen. Hypothetically, approximately one quarter of reactions detected by NACDG allergens would have been missed by TRUE TEST (SmartPractice Denmark, Hillerød, Denmark). These results affirm the value of patch testing with many allergens.

  5. Expansion of the ore treatment plant at Ranger Uranium Mines at Jabiru, NT Australia

    International Nuclear Information System (INIS)

    Nice, R.W.; Banaczkowski, M.

    2000-01-01

    The Ranger Uranium Mine commenced processing ore in 1980. The original plant designed by the joint venture between Davy and Wright Engineers had been designed to treat 1.3 Mtpa of ore to produce 3500 tpa of U 3 O 8 concentrates. The plant operated successfully through good and bad years until the 1995 when the owners of Energy Resources of Australia, North Ltd. (70%) decided that there was a market opening to allow expansion of the treatment plant such that it would produce 6000 tpa of concentrate.The desire to produce more concentrates was market driven but the change from the mine Ranger 1 to a new pit Ranger 3 also necessitated the inclusion of the ability to treat more ore. This involved the installation of more grinding and CCD washing capacity. There were some other changes that were to be included into the expansion to overcome operating deficiencies, reduce operating costs and to generally make the operation easier.The Australian engineering company, Kvaerner Davy, was commissioned to provide the EPCM services to the clients, North and the Ranger Operation Group. North Technical Services managed the Project with considerable input from the site operating and maintenance personnel. The site operating personnel commissioned the plant and are successfully operating it at the time of the preparation of this paper. The first part of this paper presents the basic process related activities required to provide the expanded facilities. This includes the flowsheet modifications, equipment changes and new equipment procured. Additionally, a discussion is given regarding the P and ID changes, the piping modifications and the means to install the expanded facilities with a minimum of interruption to the continuing plant operation. A second part of the paper details some of the experiences gained while constructing the expansion and commissioning and operating the expanded plant. (author)

  6. The treatment of uranium ores

    International Nuclear Information System (INIS)

    Michel, P.

    1979-01-01

    After having described the main steps in the treatment of uranium ores, the author describes the treament activities for these ores, as they are organized in France and in the African countries having made cooperation agreements with France in this field [fr

  7. Uranium ore processing

    International Nuclear Information System (INIS)

    Ritcey, G.M.; Haque, K.E.; Lucas, B.H.; Skeaff, J.M.

    1983-01-01

    The authors have developed a complete method of recovering separately uranium, thorium and radium from impure solids such as ores, concentrates, calcines or tailings containing these metals. The technique involves leaching, in at least one stage. The impure solids in finely divided form with an aqueous leachant containing HCl and/or Cl 2 until acceptable amounts of uranium, thorium and radium are dissolved. Uranium is recovered from the solution by solvent extraction and precipitation. Thorium may also be recovered in the same manner. Radium may be recovered by at least one ion exchange, absorption and precipitation. This amount of iron in the solution must be controlled before the acid solution may be recycled for the leaching process. The calcine leached in the first step is prepared in a two stage roast in the presence of both Cl 2 and a metal sulfide. The first stage is at 350-450 0 and the second at 550-700 0

  8. North American contact dermatitis group patch test results: 2011-2012.

    Science.gov (United States)

    Warshaw, Erin M; Maibach, Howard I; Taylor, James S; Sasseville, Denis; DeKoven, Joel G; Zirwas, Matthew J; Fransway, Anthony F; Mathias, C G Toby; Zug, Kathryn A; DeLeo, Vincent A; Fowler, Joseph F; Marks, James G; Pratt, Melanie D; Storrs, Frances J; Belsito, Donald V

    2015-01-01

    Patch testing is an important diagnostic tool for assessment of allergic contact dermatitis (ACD). This study documents the North American Contact Dermatitis Group (NACDG) patch-testing results from January 1, 2011, to December 31, 2012. At 12 centers in North America, patients were tested in a standardized manner with a series of 70 allergens. Data were manually verified and entered into a central database. Descriptive frequencies were calculated, and trends analyzed using χ statistics. Four thousand two hundred thirty-eight patients were tested; of these, 2705 patients (63.8%) had at least 1 positive reaction, and 2029 (48.0%) were ultimately determined to have a primary diagnosis of ACD. Four hundred eight patients (9.6%) had occupationally related skin disease. There were 7532 positive allergic reactions. As compared with previous reporting periods (2009-2010 and 2000-2010), positive reaction rates statistically increased for 6 allergens: methylchloroisothiazolinone/methylisothiazolinone (5.0%; risk ratios [RRs]: 2.01 [1.60-2.52], 1.87 [1.61-2.18]), lanolin alcohol (4.6%; RRs 1.83 [1.45-2.30], 2.10 [1.79-2.47]), cinnamic aldehyde (3.9%; 1.69 [1.32-2.15], 1.53 [1.28-1.82]), glutaral (1.5%; 1.67 [1.13-2.48], 1.31 [1.00-1.71]), paraben mix (1.4%; 1.77 [1.16-2.69], 1.44 [1.09-1.92]), and fragrance mix I (12.1%; RRs 1.42 [1.25-1.61], 1.24 [1.14-1.36]). Compared with the previous decade, positivity rates for all formaldehyde-releasing preservatives significantly decreased (formaldehyde 6.6%; RR, 0.82 [0.73, 0.93]; quaternium-15 6.4% RR 0.75 [0.66, 0.85]; diazolidinyl urea 2.1%; RR, 0.67 [0.54, 0.84]; imidazolidinyl urea 1.6%, 0.60 [0.47, 0.77]; bronopol 1.6%; RR, 0.60 [0.46, 0.77]; DMDM hydantoin 1.6%; RR, 0.59 [0.54, 0.84]). Approximately a quarter of patients had at least 1 relevant allergic reaction to a non-NACDG allergen. In addition, approximately one-fourth to one-third of reactions detected by NACDG allergens would have been hypothetically missed by T

  9. Studies on uranium ore processing

    International Nuclear Information System (INIS)

    Suh, I.S.; Chun, J.K.; Park, S.W.; Choi, S.J.; Lee, C.H.; Chung, M.K.; Lim, J.K.

    1983-01-01

    For the exploitation of domestic uranium ore deposit, comprehensive studies on uranium ore processing of the Geum-San pit ore are carried out. Physical and chemical characteristics of the Geum-San ore are similar to those of Goe-San ore and the physical beneficiation could not be applicable. Optimum operating conditions such as uranium leaching, solid-liquid separation, solvent extraction and precipitation of yellow cake are found out and the results are confirmed by the continous operation of the micro-plant with the capacity of 50Kg, ore/day. In order to improve the process of ore milling pilot plant installed recently, the feasibility of raffinate-recycle and the precipitation methods of yellow cake are intensively examined. It was suggested that the raffinate-recycle in the leaching of filtering stage could be reduced the environmental contamination and the peroxide precipitation technique was applicable to improve the purity of yellow cake. The mechanism and conditions the third phase formation are thoroughly studied and confirmed by chemical analysis of the third phase actually formed during the operation of pilot plant. The major constituents of the third phase are polyanions such as PMosub(12)Osub(40)sup(3-) or SiMosub(12)Osub(40)sup(4-). And the formation of these polyanions could be reduced by the control of redox potential and the addition of modifier. (Author)

  10. Towards an improved lithostratigraphic subdivision of the chalk group in the Netherlands North Sea area - A seismic stratigraphic approach

    NARCIS (Netherlands)

    Molen, A.S. van der; Wong, Th.E.

    2007-01-01

    In the Netherlands North Sea area, the Chalk Group has thus far been subdivided into the Cenomanian Texel Formation, the Turonian to Maastrichtian Ommelanden Formation and the Danian Ekofisk Formation. This paper describes the attempt to arrive at a more detailed lithostratigraphic subdivision for

  11. Towards an improved lithostratigraphic subdivision of the Chalk Group in the Netherlands North Sea area – A seismic stratigraphic approach

    NARCIS (Netherlands)

    Molen, A.S. van der; Wong, Th.E.

    In the Netherlands North Sea area, the Chalk Group has thus far been subdivided into the Cenomanian Texel Formation, the Turonian to MaastrichtianOmmelanden Formation and the Danian Ekofisk Formation. This paper describes the attempt to arrive at a more detailed lithostratigraphicsubdivision for

  12. Distribution and conservation of three important bird groups of the Atlantic Forest in north-east Brazil

    Directory of Open Access Journals (Sweden)

    G. A. Pereira

    Full Text Available Abstract The Pernambuco Endemism Center in north-east Brazil has the most fragmented forest cover and the largest number of threatened birds of the whole Atlantic Forest. We analyzed the distribution of three groups of bird species: forest-dependent, endemic and/or threatened using the interpolation method of Inverse Distance Weighting. We also checked the concentration of these birds in protected and unprotected areas, suggesting new sites that need to be protected. The richness concentration of forest-dependent, endemic and/or threatened birds in 123 sites were analysed. There was a greater concentration of the three groups in north Alagoas, south and north Pernambuco, and north and west Paraíba. The distribution of the three groups was almost regular in different vegetation types, although a lower concentration was found in the pioneer formation. There was a greater concentration of birds from all three groups between Pernambuco and Alagoas, and this must be due to the presence of more forest fragments with better structure and vegetation heterogeneity. The protected and unprotected areas hosted important records of endemic and/or threatened birds. We suggested some important places for implementation of new protected areas due to the larger concentrations of the target birds and because they are located within the boundaries of the Important Bird Areas.

  13. Distribution and conservation of three important bird groups of the Atlantic Forest in north-east Brazil.

    Science.gov (United States)

    Pereira, G A; Araújo, H F P; Azevedo-Júnior, S M

    2016-01-01

    The Pernambuco Endemism Center in north-east Brazil has the most fragmented forest cover and the largest number of threatened birds of the whole Atlantic Forest. We analyzed the distribution of three groups of bird species: forest-dependent, endemic and/or threatened using the interpolation method of Inverse Distance Weighting. We also checked the concentration of these birds in protected and unprotected areas, suggesting new sites that need to be protected. The richness concentration of forest-dependent, endemic and/or threatened birds in 123 sites were analysed. There was a greater concentration of the three groups in north Alagoas, south and north Pernambuco, and north and west Paraíba. The distribution of the three groups was almost regular in different vegetation types, although a lower concentration was found in the pioneer formation. There was a greater concentration of birds from all three groups between Pernambuco and Alagoas, and this must be due to the presence of more forest fragments with better structure and vegetation heterogeneity. The protected and unprotected areas hosted important records of endemic and/or threatened birds. We suggested some important places for implementation of new protected areas due to the larger concentrations of the target birds and because they are located within the boundaries of the Important Bird Areas.

  14. Report of Working Group 22 on Iron Supply and its Impact on Biogeochemistry and Ecosystems in the North Pacific Ocean

    OpenAIRE

    2013-01-01

    The Working Group on Iron Supply and its Impact on Biogeochemistry and Ecosystems in the North Pacific Ocean (WG 22) was established October 2007 under the direction of the Biological Oceanography Committee (BIO) and consisted of 20 members from all PICES member countries, including Co-Chairmen, Drs. Shigenobu Takeda (Japan) and Fei Chai (USA). The purpose of the Working Group was to examine the role of iron biogeochemistry and its impact on biological productivity and marine ecosystems. WG 2...

  15. Ore sorting using natural gamma radiation

    International Nuclear Information System (INIS)

    Clark, G.J.; Dickson, B.L.; Gray, F.E.

    1980-01-01

    A method of sorting an ore which emits natural gamma radiation is described, comprising the steps of: (a) mining the ore, (b) placing, substantially at the mining location, the sampled or mined ore on to a moving conveyor belt, (c) measuring the natural gamma emission, water content and mass of the ore while the ore is on the conveyor belt, (d) using the gamma, water content and mass measurements to determine the ore grade, and (e) directing the ore to a location characteristic of its grade when it leaves the conveyor belt

  16. Microbial reduction of iron ore

    Science.gov (United States)

    Hoffmann, M.R.; Arnold, R.G.; Stephanopoulos, G.

    1989-11-14

    A process is provided for reducing iron ore by treatment with microorganisms which comprises forming an aqueous mixture of iron ore, microorganisms operable for reducing the ferric iron of the iron ore to ferrous iron, and a substrate operable as an energy source for the microbial reduction; and maintaining the aqueous mixture for a period of time and under conditions operable to effect the reduction of the ore. Preferably the microorganism is Pseudomonas sp. 200 and the reduction conducted anaerobically with a domestic wastewater as the substrate. An aqueous solution containing soluble ferrous iron can be separated from the reacted mixture, treated with a base to precipitate ferrous hydroxide which can then be recovered as a concentrated slurry. 11 figs.

  17. Blood pressure and psychological distress among North Africans in France: The role of perceived personal/group discrimination and gender.

    Science.gov (United States)

    Loose, Florence; Tiboulet, Marie; Maisonneuve, Christelle; Taillandier-Schmitt, Anne; Dambrun, Michael

    2017-09-10

    The purpose of this study was to examine the associations between perceived ethnic discrimination and (physical and mental) health indicators among North African women and men living in France. This study included 82 North Africans, aged 18-64 years. Perceived discrimination was measured at both group level (PGD) and personal level (PPD). The physical health indicator was blood pressure. The mental health indicator was self-reported psychological distress. Multiple regression analyses showed that higher levels of PGD predicted higher blood pressure. PPD was not related to blood pressure. PPD was positively related to psychological distress among women, but not among men. PPD and PGD are associated with physical and mental health indicators in different ways among North African women and men in France. © 2017 Wiley Periodicals, Inc.

  18. Occupational contact dermatitis in hairdressers/cosmetologists: retrospective analysis of north american contact dermatitis group data, 1994 to 2010.

    Science.gov (United States)

    Warshaw, Erin M; Wang, Michael Z; Mathias, C G Toby; Maibach, Howard I; Belsito, Donald V; Zug, Kathryn A; Taylor, James S; Zirwas, Matthew J; Fransway, Anthony F; Deleo, Vincent A; Marks, James G; Pratt, Melanie D; Storrs, Frances J; Rietschel, Robert L; Fowler, Joseph F; Sasseville, Denis

    2012-01-01

    European studies document that occupational contact dermatitis (CD) is common in hairdressers, but studies from North America are lacking. The objectives of this study were to estimate the prevalence of occupational CD among North American hairdressers/cosmetologists (HD/CS) and to characterize responsible allergens and irritants as well as their sources. A cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group between 1994 and 2010 was conducted. Of 35,842 patients, 432 (1.2%) were HD/CS. Significantly, most of the HD/CS were female (89.8%) and younger than 40 years (55.6%) as compared with non-hairdressers (P Contact Dermatitis Group allergen series missed at least 1 occupationally-related allergen in 26.2% of patients. Contact dermatitis in North American HD/CS is common, and occupationally related allergens are those found in HD/CS products. Supplemental hairdressing/cosmetology antigen series are important in detecting all occupationally related allergens in this population.

  19. Status Report from the United Kingdom [Processing of Low-Grade Uranium Ores

    Energy Technology Data Exchange (ETDEWEB)

    North, A A [Warren Spring Laboratory, Stevenage, Herts. (United Kingdom)

    1967-06-15

    The invitation to present this status report could have been taken literally as a request for information on experience gained in the actual processing of low-grade uranium ores in the United Kingdom, in which case there would have been very little to report; however, the invitation naturally was considered to be a request for a report on the experience gained by the United Kingdom of the processing of uranium ores. Lowgrade uranium ores are not treated in the United Kingdom simply because the country does not possess any known significant deposits of uranium ore. It is of interest to record the fact that during the nineteenth century mesothermal vein deposits associated with Hercynian granite were worked at South Terras, Cornwall, and ore that contained approximately 100 tons of uranium oxide was exported to Germany. Now only some 20 tons of contained uranium oxide remain at South Terras; also in Cornwall there is a small number of other vein deposits that each hold about five tons of uranium. Small lodes of uranium ore have been located in the southern uplands of Scotland; in North Wales lower palaeozoic black shales have only as much as 50 to 80 parts per million of uranium oxide, and a slightly lower grade carbonaceous shale is found near the base of the millstone grit that occurs in the north of England. Thus the experience gained by the United Kingdom has been of the treatment of uranium ores that occur abroad.

  20. The evolution of body size in extant groups of North American freshwater fishes: speciation, size distributions, and Cope's rule.

    Science.gov (United States)

    Knouft, Jason H; Page, Lawrence M

    2003-03-01

    Change in body size within an evolutionary lineage over time has been under investigation since the synthesis of Cope's rule, which suggested that there is a tendency for mammals to evolve larger body size. Data from the fossil record have subsequently been examined for several other taxonomic groups to determine whether they also displayed an evolutionary increase in body size. However, we are not aware of any species-level study that has investigated the evolution of body size within an extant continental group. Data acquired from the fossil record and data derived from the evolutionary relationships of extant species are not similar, with each set exhibiting both strengths and weaknesses related to inferring evolutionary patterns. Consequently, expectation that general trends exhibited in the fossil record will correspond to patterns in extant groups is not necessarily warranted. Using phylogenetic relationships of extant species, we show that five of nine families of North American freshwater fishes exhibit an evolutionary trend of decreasing body size. These trends result from the basal position of large species and the more derived position of small species within families. Such trends may be caused by the invasion of small streams and subsequent isolation and speciation. This pattern, potentially influenced by size-biased dispersal rates and the high percentage of small streams in North America, suggests a scenario that could result in the generation of the size-frequency distribution of North American freshwater fishes.

  1. Correlation of lip patterns, gender, and blood group in North Kerala population: A study of over 800 individuals.

    Science.gov (United States)

    Basheer, Shaini; Gopinath, Divya; Shameena, P M; Sudha, S; Lakshmi, J Dhana; Litha

    2017-01-01

    With the ever-changing field of criminal justice, the constant revision of criteria for acceptable evidence by the judiciary poses new challenges in forensic investigation. The applicability of cheiloscopy in individual identification is an area of extensive research in recent years. The aim of the present study was to determine the distribution of different lip print patterns in North Kerala population, to assess any sexual dimorphism in lip patterns, and to correlate lip print patterns with ABO and Rh blood groups. A total of 858 students, 471 males and 387 females, from different colleges in the district of Kozhikode in North Kerala were included in the study. Lip prints were obtained using lipstick and cello tape and transferred onto white papers. Blood group of the participants was noted. The most predominant pattern observed was Type I (48.3%), followed by Type II, Type III, Type IV, Type I', and Type V. We also observed that the lower lip exhibited an overwhelming predominance of Type I pattern in the North Kerala population while the upper lip showed a more even distribution. Gender-wise difference was observed with Type II being the most common in males and Type IV being the predominant pattern in females. No correlation was obtained between the blood groups and lip patterns. The potential usefulness of cheiloscopy in forensic medicine still remains largely untapped and under-recognized. Similar studies in different populations with large sample sizes will allow a more definite picture of lip print patterns to emerge.

  2. Control of Rock Mechanics in Underground Ore Mining

    Science.gov (United States)

    Golik, V. I.; Efremenkov, A. B.

    2017-07-01

    Performance indicators in underground mining of thick iron fields can be insufficient since geo-mechanic specifics of ore-hosting fields might be considered inadequately, as a consequence, critical deformations and even earth’s surface destruction are possible, lowering the indicators of full subsurface use, this way. The reason for it is the available approach to estimating the performance of mining according to ore excavation costs, without assessing losses of valuable components and damage to the environment. The experimental approach to the problem is based on a combination of methods to justify technical capability and performance of mining technology improvement with regard to geomechanical factors. The main idea of decisions to be taken is turning geo-materials into the condition of triaxial compression via developing the support constructions of blocked up structural rock block. The study was carried out according to an integrated approach based on the analysis of concepts, field observations, and simulation with the photo-elastic materials in conditions of North Caucasus deposits. A database containing information on the deposit can be developed with the help of industrial experiments and performance indicators of the field can be also improved using the ability of ore-hosting fields to develop support constructions, keeping the geo-mechanical stability of the system at lower cost, avoiding ore contamination at the processing stage. The proposed model is a specific one because an adjustment coefficient of natural and anthropogenic stresses is used and can be adopted for local conditions. The relation of natural to anthropogenic factors can make more precise the standards of developed, prepared and ready to excavation ore reserves relying on computational methods. It is possible to minimize critical stresses and corresponding deformations due to dividing the ore field into sectors safe from the standpoint of geo-mechanics, and using less cost

  3. Radiometric enrichment of nonradioactive ores

    International Nuclear Information System (INIS)

    Mokrousov, V.A.; Lileev, V.A.

    1979-01-01

    Considered are the methods of mineral enrichment based on the use of the radioation of various types. The physical essence of enrichment processes is presented, their classification is given. Described are the ore properties influencing the efficiency of radiometric enrichment, methods of the properties study and estimation of ore enrichment. New possibilities opened by radiometric enrichment in the technology of primary processing of mineral raw materials are elucidated. A considerable attention is paid to the main and auxiliary equipment for radiometric enrichment. The foundations of the safety engineering are presented in a brief form. Presented are also results of investigations and practical works in the field of enrichment of ores of non-ferrous, ferrous and non-metallic minerals with the help of radiometric methods

  4. Chromosomal aberrations in ore miners of Slovakia

    International Nuclear Information System (INIS)

    Beno, M.; Vladar, M.; Nikodemova, D.; Vicanova, M.; Durcik, M.

    1998-01-01

    A pilot study was performed in which the incidence of chromosomal aberrations in lymphocytes of miners in ore mines located in Central Slovakia was monitored and related to lifetime underground radon exposure and to lifetime smoking. The conclusions drawn from the results of the study were as follows: the counts of chromosomal aberrations in lymphocytes of miners were significantly higher than in an age matched control group of white-collar staff; the higher counts of chromosomal aberrations could be ascribed to underground exposure of miners and to smoking; a dependence of chromosomal aberration counts on the exposure to radon could not be assessed. (A.K.)

  5. Origin of ores of endogeneous uranium ore deposits

    International Nuclear Information System (INIS)

    Kasanskij, V.I.; Laverov, N.P.; Tugarinov, A.I.

    1976-01-01

    The consideration mainly includes those endogenous uranium ore deposits of which more exact data are available, such as precambrian ones in areas of proto-activated old platforms, deposits of palaeozoic fold areas, and mesozoic deposits in areas of tectonic-magnetic activation. Their genesis and typical characters are mentioned and conclusions on the general distribution of the deposits are drawn. (author)

  6. Application of Concentration-Number and Concentration-Volume Fractal Models to Recognize Mineralized Zones in North Anomaly Iron Ore Deposit, Central Iran / Zastosowanie Modeli Fraktalnych Typu K-L (Koncentracja-Liczba), Oraz K-O (Koncentracja Objętość) Do Rozpoznawania Stref Występowania Surowców Mineralnych W Regionie Złóż Rud Żelaza North Anomaly, W Środkowym Iranie

    Science.gov (United States)

    Afzal, Peyman; Ghasempour, Reza; Mokhtari, Ahmad Reza; Haroni, Hooshang Asadi

    2015-09-01

    Identification of various mineralized zones in an ore deposit is essential for mine planning and design. This study aims to distinguish the different mineralized zones and the wall rock in the Central block of North Anomaly iron ore deposit situated in Bafq (Central Iran) utilizing the concentration-number (C-N) and concentration-volume (C-V) fractal models. The C-N model indicates four mineralized zones described by Fe thresholds of 8%, 21%, and 50%, with zones 50% Fe representing wall rocks and highly mineralized zone, respectively. The C-V model reveals geochemical zones defined by Fe thresholds of 12%, 21%, 43% and 57%, with zones 50% zawartości żelaza, co odpowiada pasmu skalnemu oraz strefie o wysokim stopniu zawartości rudy. Model koncentracja-objętość wskazuje na istnienie stref geochemicznych określonych poprzez progowe wartości zawartości żelaza: 12%, 21%, 43% i 57 % oraz strefy <12%, co odpowiada ścianie skalnej. Obydwa modele stwierdzają obecność stref o wysokim stopniu zawartości surowca w środkowej i zachodniej części złoża. Wyniki walidacji modeli fraktalnych przy użyciu modeli geologicznych wskazują, ze model fraktalny koncentracja-liczba lepiej odwzorowuje obecność stref o wysokiej zawartości rud niż model fraktalny typu koncentracja-objętość.

  7. The Vein-type Zn-(Pb, Cu, As, Hg) mineralization at Fedj Hassene ore field, North-Western Tunisia: Mineralogy, Trace Elements, Sulfur Isotopes and Fluid Inclusions; Le champ filonien a Zn-(Pb, Cu, As, Hg) du district minier de Fedj Hassene (Nord Ouest de la Tunisie): Mineralogie, Elements en traces, Isotopes du Soufre et Inclusions Fluides

    Energy Technology Data Exchange (ETDEWEB)

    Bejaouil, J.; Bouhlel, S.; Barca, D.; Braham, A.

    2011-07-01

    The Fedj Hassene district is localized at the edge of the Tuniso-Algerian border 10 km of Ghardimaou area. It consists of a Zn-Pb vein type with minor amounts of Cu-As-Hg. The total Zn reserves are about 370.000t. The mineralization occurs within sub parallel fractures to the Ain El Kohla ESE-WNW fault. Host rocks consist of limestones and marly limestones of the Middle Turonian. In the principal lode of Fedj Hassene, the mineralization occurs as vein filling of massive and brecciated brown sphalerite and minor galena ore with gangue. Other trace minerals are pyrite, chalcopyrite, orpiment, realgar, smithsonite and cerussite. LA-ICP-MS analyses in sphalerites show mean contents of 0,84 wt% Fe, 0,14 wt% Cd and 0,02 wt% Mn Ore. Fluid inclusions study in calcite and sphalerite reveals one mineralizing fluid characterized by an average salinity 23% wt NaCl with decreasing homogenisation temperature. In fact the temperature shows decrease from sphalerite to calcite. The fluid density that corresponds to trapping pressure ranges between 1.00 g/cm{sup 3} and 1.11 g/cm{sup 3} and pressure close to 200 bars. Micro thermometric data in fluid inclusion hosted by gangue mineral presented by calcite show an average temperature of formation around 194 degree centigrade. These inclusions homogenized to the liquid phase between 156 degree centigrade and 210 degree centigrade and salinities values ranging from 22 to 28 wt% NaCl and an average around 23% wt NaCl. The {delta}{sup 3}4S (VCDT) values of sphalerite are in the range of + 4,6% to 6,4% (average=5,6%). Thermochemical reduction of Triassic sulfate by reaction with hydro-carbons is the most probable source for the heavy and the narrow range of the d{delta}{sup 3}4S values. Mineralogical, geochemical of trace elements, fluid inclusions and sulfur isotopes studies allow to include the vein-type ore field of Fedj Hassene in the polymetallic (Pb-Zn-As-Hg) vein mineralization of the nappe zone in northern Tunisia and north eastern

  8. Methods of Dust Air Flows Reduction at Ore Transfer Facilities of Mining and Processing Plants

    Directory of Open Access Journals (Sweden)

    Gulmira K. Saparova

    2013-01-01

    Full Text Available The article describes the most typical schemes of ore stationary transfers. Aspirate units, depending on dust intensity are divided into three groups. Typical schemes of stationary transfers were presented. On the ground of the research, the classification of ore transfer facilities types at mining and processing plants was offered

  9. Carbon isotope variations in the upper Carboniferous - Permian Mallemuk Mountain Group, eastern North Greenland

    International Nuclear Information System (INIS)

    Stemmerik, L.; Magaritz, M.

    1989-01-01

    Isotope data from Late Palaeozoic limestones of the Wandel Sea Basin in eastern North Greenland show a variation of δ 13 C from 0.0 0/00 to 5.7 0/00 vs PDB. Carbonates depleted in 13 C occur in the basal part of lower Moscovian, upper Moscovian and middle Gzhelian transgressive sequences. 13 C enriched limestones occur later in the cycles. The most 13 C enriched limestones occur in the youngest (late Early Permian-early Late Permian) part of the sequence in Amdrup Land. The isotopic data is believed to represent changes in the global carbon cycle. Thus 13 C enriched carbonates correlate to periods of burial of organic carbon mostly as coal, while 13 C depleted carbonates formed as the result of erosion and oxidation of organic carbon during sea-level low stands. (author)

  10. Pitfalls in velocity analysis for strongly contrasting, layered media - Example from the Chalk Group, North Sea

    Science.gov (United States)

    Montazeri, Mahboubeh; Uldall, Anette; Moreau, Julien; Nielsen, Lars

    2018-02-01

    Knowledge about the velocity structure of the subsurface is critical in key seismic processing sequences, for instance, migration, depth conversion, and construction of initial P- and S-wave velocity models for full-waveform inversion. Therefore, the quality of subsurface imaging is highly dependent upon the quality of the seismic velocity analysis. Based on a case study from the Danish part of the North Sea, we show how interference caused by multiples, converted waves, and thin-layer effects may lead to incorrect velocity estimation, if such effects are not accounted for. Seismic wave propagation inside finely layered reservoir rocks dominated by chalk is described by two-dimensional finite-difference wave field simulation. The rock physical properties used for the modeling are based on an exploration well from the Halfdan field in the Danish sector of the North Sea. The modeling results are compared to seismic data from the study area. The modeling shows that interference of primaries with multiples, converted waves and thin-bed effects can give rise to strong anomalies in standard velocity analysis plots. Consequently, root-mean-square (RMS) velocity profiles may be erroneously picked. In our study area, such mis-picking can introduce errors in, for example, the thickness estimation of the layers near the base of the studied sedimentary strata by 11% to 26%. Tests show that front muting and bandpass filtering cannot significantly improve the quality of velocity analysis in our study. However, we notice that spiking deconvolution applied before velocity analysis may to some extent reduce the impact of interference and, therefore, reduce the risk of erroneous picking of the velocity function.

  11. The North Seas Countries' Offshore Grid Initiative. Initial Findings. Final Report. Working Group 1 - Grid Configuration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-15

    This report focuses on the tasks and results from Working Group 1 (WG1), grid configuration and integration, chaired jointly by representatives from Denmark and the Netherlands. The methodology, assumptions concerning generation portfolio, load situation, available technology and results are presented. This report presents the WG1 Offshore Grid Study that supports the North Seas Countries' Offshore Grid Initiative (NSCOGI) final report. The information contained in this report aims to evaluate the long-term development of an offshore grid structure in the North Seas by providing a view on how such a grid may possibly develop in the future, based on the assumptions made for this study. The report aims to compare and evaluate the possible advantages and disadvantages of the long term development of an optimised, integrated (or meshed) offshore grid in the North Seas by providing a view of how that possible grid might develop in the future against changes to the electricity energy requirements. To evaluate basic variants, different transmission design topologies (radial and meshed) were compared and analysed with respect to various aspects, such as cost/benefits, import and export levels and the systems' CO2 emissions.

  12. The pattern of distribution of ABO blood groups in North Western ...

    African Journals Online (AJOL)

    Background: Everybody over the age of about six months has clinically significant anti-A or Anti-B in their serum, if they lack the corresponding antigens on their red cells. ABO blood group antigens are the most important in blood transfusion services. This study was to determine the current incidence of ABO blood group ...

  13. Rb-Sr and Sm-Nd isotopic compositions and Petrogenesis of ore-related intrusive rocks of gold-rich porphyry copper Maherabad prospect area (North of Hanich), east of Iran

    International Nuclear Information System (INIS)

    Malekzadeh Shafaroudi, A.; Karimpour, M. H.; Mazaheri, S. A.

    2010-01-01

    The Maherabad gold-rich porphyry copper prospect area is located in the eastern part of Lut block, east of Iran. This is the first porphyry Cu-Au prospecting area which is discovered in eastern Iran. Fifteen mineralization-related intrusive rocks range (Middle Eocene 39 Ma) in composition from diorite to monzonite have been distinguished. Monzonitic porphyries had major role in Cu-Au mineralization. The ore bearing porphyries are I-type, meta luminous, high-Kcalc-alkaline to shoshonite intrusive rocks which were formed in island arc setting. These rocks are characterized by average of SiO 2 > 59 wt %, Al 2 O 3 > 15 wt %, MgO 2 O> 3 wt %, Sr> 870 ppm, Y 55, moderate Light rare earth elements, relatively low heavy rare earth elements and enrichment LILE (Sr, Cs, Rb, K and Ba) relative to HFSE (Nb, Ta, Ti, Hf and Zr). They are chemically similar to some adakites, but their chemical signatures differ in some ways from normal adakites, including higher K 2 O contents and K 2 O/Na 2 O ratios and lower Mg, (La/Yb) N , (Ce/Yb) N and εNd in Maherabad rocks. Maherabad intrusive rocks are the first K-rich adakites that can be related with subduction zone. Partial melting of mantle hybridized by hydrous, silica-rich slab-derived melts or/and input of enriched mantle-derived ultra-potassic magmas during or prior to the formation and migration of adakitic melts could be explain their high K 2 O contents and K 2 O/Na 2r atios. Low Mg values and relatively low MgO, Cr and Ni contents imply limited interaction between adakite-like magma and mantle wedge peridotite. The initial 87 Sr/ 86 Sr and ( 143 Nd/ 144 Nd)i was recalculated to an age of 39 Ma (unpublished data). Initial 87 Sr/ 86 Sr ratios for hornblende monzonite porphyry are 0.7047-0.7048. The ( 143 Nd/ 144 Nd)i isotope composition are 0.512694-0.512713. Initial εNd isotope values 1.45-1.81. These values could be considered as representative of oceanic slab-derived magmas. Source modeling indicates that high-degree of

  14. Method of continuous pressure leaching of ores

    International Nuclear Information System (INIS)

    Fiala, P.; Baloun, S.; Polansky, M.

    1987-01-01

    Ore leaching, especially suspensions of ground ore or fine ore fractions from physical treatment was divided into two operations. The former, i.e., ore mixing with technical grade concentrated sulfuric acid proceeded in a separate mixer. The mixture was then transported into an autoclave where the actual leaching proceeded for 2 to 4 hours. The extracted mixture was discharged through the autoclave bottom. The leaching autoclave used can be without any inner structures. The separation of mixing from the actual leaching allows processing ores with high levels of clay components, increasing operating reliability of the facility, reducing consumption of special structural materials and energy, and increasing process efficiency. (E.S.)

  15. Ore reserve estimation: a summary of principles and methods

    International Nuclear Information System (INIS)

    Marques, J.P.M.

    1985-01-01

    The mining industry has experienced substantial improvements with the increasing utilization of computerized and electronic devices throughout the last few years. In the ore reserve estimation field the main methods have undergone recent advances in order to improve their overall efficiency. This paper presents the three main groups of ore reserve estimation methods presently used worldwide: Conventional, Statistical and Geostatistical, and elaborates a detaited description and comparative analysis of each. The Conventional Methods are the oldest, less complex and most employed ones. The Geostatistical Methods are the most recent precise and more complex ones. The Statistical Methods are intermediate to the others in complexity, diffusion and chronological order. (D.J.M.) [pt

  16. The overthrust structural systems and their dynamics in Xiangshan uranium ore field in central Jiangxi Province

    International Nuclear Information System (INIS)

    Zhou Yulong; Gao Yan; Cao Shousun; Ji Gaoping

    2011-01-01

    Through the comprehensive study on the exploration data of the deposits in the northern part of Xiangshan uranium ore field, the overthrust structure is recognized deeply. The overthrust structure strikes EW on the whole and the direction of movement is from south to north. The main detachment surface occurred between Sinian (Z) metamorphic rocks and Jurassic (J 3 d 1 ) layers. Sinian metamorphic basement is overthrust on the top of Lower Daguding member of Upper Jurassic Group. The nappe system consists of front faults, back thrust fault,the main detachment zone (main structure), and nappe structural window. The nappe had moved 3∼4.5 km and it mainly formed during Late Jurassic, i.e. Late Yanshan.(authors)

  17. Processing of low-grade uranium ores

    International Nuclear Information System (INIS)

    Michel, P.

    1975-01-01

    Four types of low grade ores are studied. Low grade ores which must be extracted because they are enclosed in a normal grade deposit. Heap leaching is the processing method which is largely used. It allows to obtain solutions or preconcentrates which may be delivered at the nearest plant. Normal grade ores contained in a low amplitude deposit which can be processed using leaching as far as the operation does not need any large expensive equipment. Medium grade ores in medium amplitude deposits to which a simplified conventional process can be applied using fast heap leaching. Low grade ores in large deposits. The processing possibilities leading to use in place leaching are explained. The operating conditions of the method are studied (leaching agent, preparation of the ore deposit to obtain a good tightness with regard to the hydrological system and to have a good contact between ore and reagent) [fr

  18. Lithostratigraphy of Espinhaco supergroup and Bambini group in the north-west of Bahia state

    International Nuclear Information System (INIS)

    Silva, M.E. da; Karmann, J.; Trompette, R.

    1989-01-01

    The lithostragraphic aspects of the Middle to Upper Proterozoic metasedimentary sequences of the Espinhaco Supergroup and the Bambui Group in northwest Bahia, east-central Brazil, have been studied. The studied area was divided five tectonic domains on the basis of differences in metamorphism and style of folding. This paper proposes the subdivision of Bambui Group into four formations, from bottom to top: Canabravinha, Sao Desiderio, Serra da Mamona, and Riachao das Neves, here correlated, respectively, with Jequitai, Lagoa do Jacare, Serra da Saudade, and Tres Marias formations, all well characterized further south in the State of Minas Gerais. The Espinhaco Supergroup is separable into two metasedimentary units. The younger one, here defined as the Rio Preto Group, was involved in the evolution of the Rio Preto Fold System and contains mainly siliciclastic sediments correlable with the Chapada Diamantina Group. The older unit belongs to the Espinhaco Fold Belt and also is composed mostly of detritic sediments. This sequences in the Santo Onofre Group. (author0 [pt

  19. Distribution of the ore elements in ore bodies of the Zapolyarnoe field (Kola Peninsula

    Directory of Open Access Journals (Sweden)

    D. V. Taymasov

    2017-12-01

    Full Text Available The author conducted studies of the chemical zonality of ore deposits of all types for the sulfide-copper-nickel deposit Zapolyarnoe. Within the deposit of sulfide-copper-nickel ores Zapolyarnoe are the following industrial types of ores: rich interspersed ores, which are interspersed mineralization in peridotites; brecciated ores formed by detrital material; poor interspersed ores characterized by vein-interspersed mineralization; solid ores in a form of massive sulphide emissions. This work is based on operational and detailed exploration data. The author sorted samples according to the types of ores. Using the results, the author derived regression lines and their formulas to rectilinear dependencies. Analysis of the graphs showed that for all types of ores the dependences of copper and cobalt content on nickel content are direct, but at that, in thick-interspersed and brecciated types they are similar, and in scattered-interspersed they differ significantly. It becomes clear that correlation of copper and nickel in ore body depends on the scattered-interspersed ores, whereas the correlation of cobalt and nickel is determined mainly by thick-interspersed and brecciated ores. Dependencies between nickel, copper and cobalt in ores change when concentration of nickel in the ore changes. The graphs also show that the ratio of Ni/Cu in breccias and scattered-interspersed ores, as well as in near-ore metaperidotites, is almost constant at different nickel concentrations, on average 2:1.5 and 1, respectively. Thick- interspersed ores show the tendency towards an increase in the ratio with an increase in nickel content. The Ni/Co ratio increases with an increase of Ni concentration in all types of ores. In rich ores, growth occurs along a stepped curve, and in breccias – rectilinearly. Thus, the analysis of distribution of ore elements in ore bodies indicates a complex heterogeneous composition of sulphide mineralizations in different types of ores

  20. Self-Advocacy Groups: 1994-95 Directory for North America.

    Science.gov (United States)

    Hayden, Mary F.; Senese, Dick

    This 1994-95 directory of disability self-advocacy groups contains listings of over 700 organizations in the United States, Mexico, and Canada. The associations are organized by country and state or province. Listings typically contain the following information: the name of a contact (the name of the member who is the chair, president, or…

  1. University of North Carolina Council on Biotechnology Patent Task Group Report.

    Science.gov (United States)

    Journal of College and University Law, 1982

    1982-01-01

    A report of a task group on biomedical patents summarizes the context in which technological innovation involving research institutions and industry takes place and the interests and concerns of various participants. Suggestions are given for accommodating these concerns through institutional policies and procedures. (MSE)

  2. Ore microscopy applied to beneficiation

    International Nuclear Information System (INIS)

    Hagni, R.D.

    1978-01-01

    Ore microscopy can be an important adjunct to beneficiation, because it can be used not only to predict mill problems of undeveloped ore deposits but to identify the causes for the loss of minerals in the products of operating mines and mills. Mineral distribution among various mill products can be determined by examining polished sections prepared from samples obtained from each step of the beneficiation process. The degree of liberation of each mineral can be quantitatively determined for each mill product by counting locked vs. free particles. For many beneficiation problems, the preparation of a few polished sections of carefully selected mill products can yield useful information, which the mill dressing engineer can effectively use to alleviate those problems

  3. Fluid evolution and ore genesis of the Dalingshang deposit, Dahutang W-Cu ore field, northern Jiangxi Province, South China

    Science.gov (United States)

    Peng, Ning-Jun; Jiang, Shao-Yong; Xiong, Suo-Fei; Pi, Dao-Hui

    2018-02-01

    The Dalingshang W-Cu deposit is located in the North section of the Dahutang ore field, northern Jiangxi Province, South China. Vein- and breccia-style tungsten-copper mineralization is genetically associated with Mesozoic S-type granitic rocks. Infrared and conventional microthermometric studies of both gangue and ore minerals show that the homogenization temperatures for primary fluid inclusions in wolframite ( 340 °C) are similar to those in scheelite ( 330 °C), but about 40 °C higher than those of apatite ( 300 °C) and generally 70 °C higher than those in coexisting quartz ( 270 °C). Laser Raman analysis identifies CH4 and N2 without CO2 in fluid inclusions in scheelite and coexisting quartz, while fluid inclusions in quartz of the sulfide stage have variable CO2 content. The ore-forming fluids overall are characterized by high- to medium-temperature, low-salinity, CH4, N2, and/or CO2-bearing aqueous fluids. Chalcopyrite, muscovite, and sphalerite are the most abundant solids recognized in fluid inclusions from different ores. The H-O-S-Pb isotope compositions favor a dominantly magmatic origin for ores and fluids, while some depleted δ34S values (- 14.4 to - 0.9‰) of sulfides from the sulfide stage are most likely produced by an increase of oxygen fugacity, possibly caused by inflow of oxidized meteoric waters. The microthermometric data also indicate that a simple cooling process formed early scheelite and wolframite. However, increasing involvement of meteoric waters and fluid mixing may trigger a successive deposition of base metal sulfides. Fluid-rock interaction was critical for scheelite mineralization as indicated by in-situ LA-ICP-MS analysis of trace elements in scheelite.

  4. Geology and ore deposits of the Section 23 Mine, Ambrosia Lake District, New Mexico

    Science.gov (United States)

    Granger, H.C.; Santos, E.S.

    1982-01-01

    The section 23 mine is one of about 18 large uranium mines opened in sandstones of the fluvial Westwater Canyon Member of the Jurassic Morrison Formation in the Ambrosia Lake mining district during the early 1960s. The Ambrosia Lake district is one of several mining districts within the Grants mineral belt, an elongate zone containing many uranium deposits along the southern flank of the San Juan basin. Two distinct types of ore occur in the mine. Primary ore occurs as peneconcordant layers of uranium-rich authigenic organic matter that impregnates parts of the reduced sandstone host rocks and which are typically elongate in an east-southeast direction subparallel both to the sedimentary trends and to the present-day regional strike of the strata. These are called prefault or trend ores because of their early genesis and their elongation and alinement. A second type of ore in the mine is referred to as postfault, stacked, or redistributed ore. Its genesis was similar to that of the roll-type deposits in Tertiary rocks of Wyoming and Texas. Oxidation, related to the development of a large tongue of oxidized rock extending from Gallup to Ambrosia Lake, destroyed much of the primary ore and redistributed it as massive accumulations of lower grade ores bordering the redox interface at the edge of the tongue. Host rocks in the southern half of sec. 23 (T. 14 N., R. 10 W.) are oxidized and contain only remnants of the original, tabular, organic-rich ore. Thick bodies of roll-type ore are distributed along the leading edge of the oxidized zone, and pristine primary ore is found only near the north edge of the section. Organic matter in the primary ore was derived from humic acids that precipitated in the pores of the sandstones and fixed uranium as both coffinite and urano-organic compounds. Vanadium, molybdenum, and selenium are also associated with the ore. The secondary or roll-type ores are essentially free of organic carbon and contain uranium both as coffinite and

  5. Water supply management using an extended group fuzzy decision-making method: a case study in north-eastern Iran

    Science.gov (United States)

    Minatour, Yasser; Bonakdari, Hossein; Zarghami, Mahdi; Bakhshi, Maryam Ali

    2015-09-01

    The purpose of this study was to develop a group fuzzy multi-criteria decision-making method to be applied in rating problems associated with water resources management. Thus, here Chen's group fuzzy TOPSIS method extended by a difference technique to handle uncertainties of applying a group decision making. Then, the extended group fuzzy TOPSIS method combined with a consistency check. In the presented method, initially linguistic judgments are being surveyed via a consistency checking process, and afterward these judgments are being used in the extended Chen's fuzzy TOPSIS method. Here, each expert's opinion is turned to accurate mathematical numbers and, then, to apply uncertainties, the opinions of group are turned to fuzzy numbers using three mathematical operators. The proposed method is applied to select the optimal strategy for the rural water supply of Nohoor village in north-eastern Iran, as a case study and illustrated example. Sensitivity analyses test over results and comparing results with project reality showed that proposed method offered good results for water resources projects.

  6. Spatio-temporal evolution of Leucophyllum pringlei and allies (Scrophulariaceae): a group endemic to North American xeric regions.

    Science.gov (United States)

    Gándara, Etelvina; Sosa, Victoria

    2014-07-01

    The taxa of the Leucophyllum pringlei clade were used to understand the influence of the Neogene orogenesis and the Quaternary climate cycles on the diversification of the flora of the xeric regions of North America. This clade includes the five southernmost species of the genus: L. ambiguum, L. flyrii, L. pruinosum and L. ultramonticola, which are distributed throughout the Chihuahuan Desert north of the Trans-Mexican Volcanic Belt, and L. pringlei in the region of Tehuacán-Cuicatlán south of this mountain range. Here we test whether these species diverged during the pluvial periods of the Pleistocene, and whether L. pringlei diverged earlier from the other species during the uplift of the Trans-Mexican Volcanic Belt. Using three plastid regions (psbA-trnH, psbK-psbI, trnL-F) and a nuclear (ITS) marker, phylogenetic analyses were carried out, along with a reconstruction of their ancestral area. Trees retrieved the five species in a monophyletic group with the most recent common ancestor distributed in the Sinaloan dry forest during the Late Miocene (8.08Ma), from where it dispersed to the Chihuahuan Desert during the Late Miocene (6.35Ma). The secondary uplift of the Sierra Madre Occidental during the Late Miocene to Early Pliocene influenced a vicariance event. Divergence between L. pringlei and the species from north of the Trans-Mexican Volcanic Belt occurred during the second volcanic episode in the Late Miocene (7.5-3Ma). The most recent common ancestor of L. ambiguum, L. pruinosum and L. ultramonticola was widely distributed in the southern part of the Chihuahuan Desert during the Early to Late Pliocene (3.50Ma). The diversification of these three species occurred in the Middle Pleistocene (0.9Ma) during the pluvial and inter-pluvial cycles. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Repeated Reticulate Evolution in North American Papilio machaon Group Swallowtail Butterflies.

    Directory of Open Access Journals (Sweden)

    Julian R Dupuis

    Full Text Available Hybridization between distinct populations or species is increasingly recognized as an important process for generating biodiversity. However, the interaction between hybridization and speciation is complex, and the diverse evolutionary outcomes of hybridization are difficult to differentiate. Here we characterize potential hybridization in a species group of swallowtail butterflies using microsatellites, DNA sequences, and morphology, and assess whether adaptive introgression or homoploid hybrid speciation was the primary process leading to each putative hybrid lineage. Four geographically separated hybrid populations were identified in the Papilio machaon species group. One distinct mitochondrial DNA clade from P. machaon was fixed in three hybrid taxa (P. brevicauda, P. joanae, and P. m. kahli, while one hybrid swarm (P. zelicaon x machaon exhibited this hybrid mtDNA clade as well as widespread parental mtDNA haplotypes from both parental species. Microsatellite markers and morphology showed variable admixture and intermediacy, ranging from signatures of prolonged differential introgression from the paternal species (P. polyxenes/P. zelicaon to current gene flow with both parental species. Divergences of the hybrid lineages dated to early- to mid-Pleistocene, suggesting that repeated glaciations and subsequent range shifts of parental species, particularly P. machaon hudsonianus, facilitated initial hybridization. Although each lineage is distinct, P. joanae is the only taxon with sufficient evidence (ecological separation from parental species to define it as a homoploid hybrid species. The repetition of hybridization in this group provides a valuable foundation for future research on hybridization, and these results emphasize the potential for hybridization to drive speciation in diverse ways.

  8. The Association of Race/Ethnicity and Patch Test Results: North American Contact Dermatitis Group, 1998-2006.

    Science.gov (United States)

    Deleo, Vincent Anthony; Alexis, Andrew; Warshaw, Erin M; Sasseville, Denis; Maibach, Howard I; DeKoven, Joel; Zug, Kathryn A; Belsito, Donald V; Fowler, Joseph F; Marks, James G; Mathias, C G Toby; Pratt, Melanie D; Rietschel, Robert L; Storrs, Frances J; Taylor, James S; Zirwas, Matthew

    2016-01-01

    The North American Contact Dermatitis Group patch tests patients with suspected allergic contact dermatitis (ACD) to a broad series of screening allergens and publishes periodic reports. We have previously reported on the association of race and ethnicity with the rates of positive responses to standard patch test allergens. This report extends those observations. The aim of the study was to report the North American Contact Dermatitis Group patch testing results from January 1, 1998, to December 31, 2006, comparing the frequency of positive reactions between white and black subjects. Standardized patch testing with 45 allergens was used at 13 centers in North America. χ analysis of results in black subjects as compared with whites was examined. A total of 19,457 patients were tested; 92.9% (17,803) were white and 7.1% (1,360) were black. The final diagnoses of ACD (whites, 45.9%; blacks, 43.6%) and irritant contact dermatitis (13.0%/13.3%) were similar in the 2 groups. The diagnosis of atopic dermatitis was less common in the white patients (8.9%) as compared with the black patients (13.3%). Positive patch test reactions rates were similar for most allergens. However, statistically, blacks reacted more frequently to p-phenylenediamine (7.0% vs 4.4%, P < 0.001), bacitracin (11.6% vs 8.3%, P = 0.0004), as well as specific rubber accelerators mercaptobenzothiazole (2.7% vs 1.8%), thiuram (6.2% vs 4.3%), and mercapto mix (1.9% vs 0.8%, P < 0.001). Whites had an increase in positive reactions to fragrances (12.12% vs 6.77%, P < 0.0001), formaldehyde (9.25% vs 5.45%, P < 0.0001), and some formaldehyde releaser preservatives used in personal care products and textile resins (9.80% vs 6.18%, P < 0.0001). There were statistically different rates of positive patch test reactions to specific allergens between black and white patients suspected of having ACD. The etiology of these differences is unclear but probably relates to culturally determined exposure patterns rather

  9. Analysis of copper-nickel ores by gamma-gamma method in ore enrichment works

    International Nuclear Information System (INIS)

    Bol'shakov, A.Yu.; Tovstenko, Yu.G.; Chinskij, E.B.; Eliseev, G.I.

    1973-01-01

    The paper presents experimental data on continuous gamma-gamma assay of copper-nickel ores on conveyor belts and of dry discrete samples of classifier overflow at the enrichment plants of the Pechenganikel' group. The relative errors are given of the results of comparison of two-hour rapid analyses and shift and 24-hour chemical analyses of classifier overflow samples with the figures for gamma-gamma assay. The factors affecting the accuracy of the latter technique are elucidated. Practical recommendations are given on the use of this technique at the above enrichment plants. (author)

  10. Microbial leaching of low grade copper ores

    International Nuclear Information System (INIS)

    Rauf, A.; Ashfaq, M.

    1991-01-01

    Biotechnology is regarded as one of the most promising and revolutionary solution to various problems which are generally faced in the extraction of metals from their ores such as high energy, capital costs and environmental pollution. The paper deals with the study of low grade copper ores for their beneficiation and extraction of copper. The ores used were chalcopyrite and oxidized copper ores. Microorganisms play a vital role in the solubilization of valuable contents from ores such as copper and other metals. Studies have been conducted on the indigenous copper ores by using thiobacillus ferro oxidans and thiobacillus thio oxidans. For comparison purpose some experiments have also been conducted by chemical leaching. The results of bacterial leaching are encouraging. (author)

  11. Processing of low grade uranium ores

    International Nuclear Information System (INIS)

    Michel, P.

    1978-10-01

    Four types of low-grade ores are studied: (1) Low-grade ores that must be extracted because they are enclosed in a normal-grade deposit. Heap leaching is the processing method which is largely used. (2) Normal-grade ores contained in low-amplitude deposits. They can be processed using in-place leaching as far as the operation does not need any large and expensive equipment. (3) Medium-grade ores in medium-amplitude deposits. A simplified conventional process can be applied using fast heap leaching. (4) Low-grade ores in large deposits. The report explains processing possibilities leading in most cases to the use of in-place leaching. The operating conditions of this method are laid out, especially the selection of the leaching agents and the preparation of the ore deposit

  12. Reasons for non-immunization of children in an urban, low income group in North India.

    Science.gov (United States)

    Mathew, Joseph L; Babbar, Harsh; Yadav, Sangita

    2002-07-01

    A study was undertaken on 500 children under the age of 5 years belonging to a low income group. All were attending the paediatrics outpatient department of a large teaching hospital in New Delhi, India. Only 25% were found to have received complete primary immunization as per the National Immunization Schedule (bacille Calmette-Guérin at birth, three doses of diphtheria, pertussis and tetanus and oral poliovirus vaccine at 6,10 and 14 weeks and measles vaccine at 9 months). The major reasons for non-immunization of the children were: migration to a native village (26.4%); domestic problems (9.6%); the immunization centre was located too far from their home (9.6%); and the child was unwell when the vaccination was due (9%). Twelve per cent of mothers could not give any reason for non-immunization. In addition to the migration of children to rural areas, the other significant finding was an indirect effect of intensive OPV administration as part of polio eradication initiative. The lack of awareness and fear of side effects constituted a small minority of reasons for non-immunization.

  13. Trace element similarity groups in north Florida Spanish moss: evidence for direct uptake of aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Sheline, J.; Akselsson, R.; Winchester, J.W.

    1976-02-20

    The elemental composition of 10 samples of Spanish moss Tillandsia usneoides L. collected mainly in forested areas near Tallahassee, Florida, has been compared to the composition of the ambient aerosol particle background in the forest measured as a function of particle size. For forest samples, moss composition is similar to the composition of aerosol particles greater than about 0.5-..mu..m diameter for the elements S, Cl, Ti, V, Fe, Ni, Zn, Br, Pb, and possibly Cu. Elements relatively enriched in the moss fall into two groups, K, Rb, Zr and Ca, Sr, Mn, based on detailed association patterns. No evidence is found for an enrichment, relative to the ambient aerosol, of pollution-derived elements Pb, Br, V, and Ni, although those elements are found at higher concentrations in moss samples from locations nearer roadways or oil-fired power plants. The moss appears to have potential value as an indicator of time average aerosol composition for particles of greater than or equal to 0.5 ..mu..m, except for the enriched elements, which may have longer biological retention times. (auth)

  14. The history of critical group doses from the consumption of freshwater fish at Trawsfynydd, North Wales

    International Nuclear Information System (INIS)

    Leonard, D.R.P.

    1992-01-01

    Radionuclides discharged into the aquatic environment from Trawsfynydd power station are, as for all UK facilities, subject to statutory controls to ensure that the resulting public radiation exposure complies with nationally-accepted criteria. Environmental monitoring by MAFF has shown that near this facility the consumption of freshwater fish is radiologically the most important pathway with Cs-137 the dominant radionuclide. Information gathered from consumers over a twenty-five year period has been interpreted so as to derive doses to the public. Committed effective doses (CEDs) are presented using ICRP 1990 methodology and compared with the recommended dose limit of 1 mSv year -1 . Doses to the critical group are shown to have exceeded 1 mSv year -1 for two years but do not exceed this limit when averaged over a period of 5 years. Because of the changing habits of the consumers it is suggested that the average annual CED over the lifetime of any member of the public will not exceed 1 mSv year -1 during the operation of the station. (author)

  15. Nanoscale Study of Clausthalite-Bearing Symplectites in Cu-Au-(U Ores: Implications for Ore Genesis

    Directory of Open Access Journals (Sweden)

    Nicholas D. Owen

    2018-02-01

    Full Text Available Symplectites comprising clausthalite (PbSe and host Cu-(Fe-sulphides (chalcocite, bornite, and chalcopyrite are instructive for constraining the genesis of Cu-Au-(U ores if adequately addressed at the nanoscale. The present study is carried out on samples representative of all three Cu-(Fe-sulphides displaying clausthalite inclusions that vary in size, from a few µm down to the nm-scale (<5 nm, as well as in morphology and inclusion density. A Transmission Electron Microscopy (TEM study was undertaken on foils prepared by Focussed Ion Beam and included atom-scale High-Angle Annular Dark-Field Scanning TEM (HAADF-STEM imaging. Emphasis is placed on phase relationships and their changes in speciation during cooling, as well as on boundaries between inclusions and host sulphide. Three species from the chalcocite group (Cu2–xS are identified as 6a digenite superstructure, monoclinic chalcocite, and djurleite. Bornite is represented by superstructures, of which 2a and 4a are discussed here, placing constraints for ore formation at T > 265 °C. A minimum temperature of 165 °C is considered for clausthalite-bearing symplectites from the relationships with antiphase boundaries in 6a digenite. The results show that alongside rods, blebs, and needle-like grains of clausthalite within the chalcocite that likely formed via exsolution, a second, overprinting set of replacement textures, extending down to the nanoscale, occurs and affects the primary symplectites. In addition, other reactions between pre-existing Se, present in solid solution within the Cu-(Fe-sulphides, and Pb, transported within a fluid phase, account for the formation of composite, commonly pore-attached PbSe and Bi-bearing nanoparticles within the chalcopyrite. The inferred reorganisation of PbSe nanoparticles into larger tetragonal superlattices represents a link between the solid solution and the symplectite formation and represents the first such example in natural materials

  16. Spatial variability in intertidal macroalgal assemblages on the North Portuguese coast: consistence between species and functional group approaches

    Science.gov (United States)

    Veiga, P.; Rubal, M.; Vieira, R.; Arenas, F.; Sousa-Pinto, I.

    2013-03-01

    Natural assemblages are variable in space and time; therefore, quantification of their variability is imperative to identify relevant scales for investigating natural or anthropogenic processes shaping these assemblages. We studied the variability of intertidal macroalgal assemblages on the North Portuguese coast, considering three spatial scales (from metres to 10 s of kilometres) following a hierarchical design. We tested the hypotheses that (1) spatial pattern will be invariant at all the studied scales and (2) spatial variability of macroalgal assemblages obtained by using species will be consistent with that obtained using functional groups. This was done considering as univariate variables: total biomass and number of taxa as well as biomass of the most important species and functional groups and as multivariate variables the structure of macroalgal assemblages, both considering species and functional groups. Most of the univariate results confirmed the first hypothesis except for the total number of taxa and foliose macroalgae that showed significant variability at the scale of site and area, respectively. In contrast, when multivariate patterns were examined, the first hypothesis was rejected except at the scale of 10 s of kilometres. Both uni- and multivariate results indicated that variation was larger at the smallest scale, and thus, small-scale processes seem to have more effect on spatial variability patterns. Macroalgal assemblages, both considering species and functional groups as surrogate, showed consistent spatial patterns, and therefore, the second hypothesis was confirmed. Consequently, functional groups may be considered a reliable biological surrogate to study changes on macroalgal assemblages at least along the investigated Portuguese coastline.

  17. Technological pretreatment of the synchysite non-oxidized ore

    Science.gov (United States)

    Munkhtsetseg, B.; Burmaa, G.

    2013-06-01

    Mongolia has rich deposits of rare, precious, and poly-metallic ores. Nowadays, it is important to research separation of rare earth elements oxides concentrates from the ores, analyze their unique physical chemical characteristics, and purified it. Our investigation on raw materials focuses on rare earth non-oxidized ores. Main mineral in this rock sample is Synchysite (LnCa(CO3)2F. We did technological and thermal pretreatment: direct sulphurization (H2SO4), sulphurization with subsequent roasting (800°C+H2SO4), sulphurization prior to roasting (H2SO4+650°C). Sulphurization method based on dissolution of rare earth mineral into sulfuric acid (93%) according to the reaction. The amount of rare earth element oxides is almost 10 times greater (29.16%) after direct sulphurization process, almost 8 times greater (21.14%) after sulphurization with subsequent roasting, and almost 20 times greater (44.62%) after sulphurization prior to roasting process. After those technological pretreatment raw material's micro elements Thorium and Uranium contents are reduced as follows: H2SO4>800°C+H2SO4>H2SO4+650°C. These results show that cerium group rare earth elements have very good solubility in water at +2°C temperature and decreasing micro elements content uranium and thorium good pretreatment condition is prior to roasting (H2SO4+650°C) of synchysite non-oxidized ore.

  18. Isotope characteristics of the sulphide-bearing sequence of the areachap group in the Boksputs area, North-West Cape

    International Nuclear Information System (INIS)

    Cilliers, F.H.

    1987-06-01

    The Boksputs stratiform sulphide deposit is situated in the eastern marginal zone of the Namaqua Province, South Africa, within the Boksputs Formation (previously termed Jannelsepan Formation). Pyrite, chalcopyrite and sphalerite are the most abundant minerals in the disseminated and thinly banded ore. The sulphide mineralization and host rocks have been deformed by at least four phases of folding followed by shearing and faulting. Major and trace element abundances (including REE), U-Pb and Sm-Nd isotope systematics indicate that changes owing to metamorphism are essentially isochemical in the amphibolite, which was derived from a mantle source. U-Pb isotope analysis were carried out on 24 amphibolite, 6 gneiss, 6 quartz-monzodiorite and 7 pyrite samples while Sm-Nd isotope analyses were performed on 6 amphibolite samples. A Pb-Pb isochron age of 1665 ± 140 Ma for the amphibolite samples indicates that the metavolcanic succession was extruded or emplaced before the Namaqua tectogenesis. The 1271 ± 53 Ma isochron age obtained for the gneiss samples is thus interpreted as a reset age, reflecting the Namaqualand metamorphic episode. It is proposed that the Boksputs mineralization like the Prieska Cu-Zn ore body, Areachap ore and Kielder sulphides, formed approximately 1500 to 1600 Ma ago as a syngenetic exhalative deposit, in a tectonic environment dominated by mantle derived tholeiitic volcanism with contemporaneous sedimentation. It is suggested that the hydrothermal fluid responsible for mineralization originated from a primary source, which must have been homogeneous, with respect to lead isotopic composition, over a large distance. The diversity of the volcano-sedimentary successions below the different ore bodies and overall similarity in Pb isotopic character, negates the possibility that the metals were leached from these rocks and a source related to a deep seated magma of mantle origin is proposed. It is concluded that Pb isotope systematics can be used

  19. Exclusion and Inclusion of Nonwhite Ethnic Minority Groups in 72 North American and European Cardiovascular Cohort Studies.

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available BACKGROUND: Cohort studies are recommended for understanding ethnic disparities in cardiovascular disease. Our objective was to review the process for identifying, including, and excluding ethnic minority populations in published cardiovascular cohort studies in Europe and North America. METHODS AND FINDINGS: We found the literature using Medline (1966-2005, Embase (1980-2001, Cinahl, Web of Science, and citations from references; consultations with colleagues; Internet searches; and RB's personal files. A total of 72 studies were included, 39 starting after 1975. Decision-making on inclusion and exclusion of racial/ethnic groups, the conceptual basis of race/ethnicity, and methods of classification of racial/ethnic groups were rarely explicit. Few publications provided details on the racial/ethnic composition of the study setting or sample, and 39 gave no description. Several studies were located in small towns or in occupational settings, where ethnic minority populations are underrepresented. Studies on general populations usually had too few participants for analysis by race/ethnicity. Eight studies were explicitly on Caucasians/whites, and two excluded ethnic minority groups from the whole or part of the study on the basis of language or birthplace criteria. Ten studies were designed to compare white and nonwhite populations, while five studies focused on one nonwhite racial/ethnic group; all 15 of these were performed in the US. CONCLUSIONS: There is a shortage of information from cardiovascular cohort studies on racial/ethnic minority populations, although this has recently changed in the US. There is, particularly in Europe, an inequity resulting from a lack of research data in nonwhite populations. Urgent action is now required in Europe to address this disparity.

  20. New interpretation of the dominant ore-controlling factor of the uranium ore field No. 322

    International Nuclear Information System (INIS)

    Liu Xiang; Yang Chongqiu

    1996-01-01

    The NE-trending fault structures in ore field NO. 322 are characterized by compress-shearing, left-Lateral left-slipping, having an obvious control over the Localisation of the ore field No. 322, and are the dominant ore-controlling factor of the ore field NO.322. Resulting from the sinistral displacement of the NE-trending fault, there is a pull-apart basin in the Feng Zhou area. The formation and evolution of the NE-trending fault zone and the Feng Zhou basin control the formation of uranium deposits of ore field No. 322

  1. Discussion on prospecting potential for rich uranium deposits in Xiazhuang uranium ore-field, northern Guangdong

    International Nuclear Information System (INIS)

    Wu Lieqin; Tan Zhengzhong

    2004-01-01

    Based on analyzing the prospecting potential for uranium deposits in Xiazhuang uranium ore field this paper discusses the prospecting for rich uranium deposits and prospecting potential in the region. Research achievements indicate: that the Xiazhuang ore-field is an ore-concentrated area where uranium has been highly enriched, and possesses good prospecting potential and perspective, becoming one of the most important prospecting areas for locating rich uranium deposits in northern Guangdong; that the 'intersection type', the alkaline metasomatic fractured rock type and the vein-group type uranium deposits are main targets and the prospecting direction for future uranium prospecting in this region

  2. Iron from Zealandic bog iron ore -

    DEFF Research Database (Denmark)

    Lyngstrøm, Henriette Syrach

    2011-01-01

    og geologiske materiale, metallurgiske analyser og eksperimentel arkæologiske forsøg - konturerne af en jernproduktion med udgangspunkt i den sjællandske myremalm. The frequent application by archaeologists of Werner Christensen’s distribution map for the occurrence of bog iron ore in Denmark (1966...... are sketched of iron production based on bog iron ore from Zealand....

  3. Multidisciplinary group performance – measuring integration intensity in the context of the North West London Integrated Care Pilot

    Directory of Open Access Journals (Sweden)

    Matthew Harris

    2013-02-01

    Full Text Available Introduction: Multidisciplinary Group meeting (MDGs are seen as key facilitators of integration, moving from individual to multi-disciplinary decision making, and from a focus on individual patients to a focus on patient groups.  We have developed a method for coding MDG transcripts to identify whether they are or are not vehicles for delivering the anticipated efficiency improvements across various providers and apply it to a test case in the North West London Integrated Care Pilot.  Methods:  We defined 'integrating' as the process within the MDG meeting that enables or promotes an improved collaboration, improved understanding, and improved awareness of self and others within the local healthcare economy such that efficiency improvements could be identified and action taken.  Utterances within the MDGs are coded according to three distinct domains grounded in concepts from communication, group decision-making, and integrated care literatures - the Valence, the Focus, and the Level.  Standardized weighted integrative intensity scores are calculated across ten time deciles in the Case Discussion providing a graphical representation of its integrative intensity. Results: Intra- and Inter-rater reliability of the coding scheme was very good as measured by the Prevalence and Bias-adjusted Kappa Score.  Standardized Weighted Integrative Intensity graph mirrored closely the verbatim transcript and is a convenient representation of complex communication dynamics. Trend in integrative intensity can be calculated and the characteristics of the MDG can be pragmatically described. Conclusion: This is a novel and potentially useful method for researchers, managers and practitioners to better understand MDG dynamics and to identify whether participants are integrating.  The degree to which participants use MDG meetings to develop an integrated way of working is likely to require management, leadership and shared values.

  4. Multidisciplinary group performance – measuring integration intensity in the context of the North West London Integrated Care Pilot

    Directory of Open Access Journals (Sweden)

    Matthew Harris

    2013-02-01

    Full Text Available Introduction: Multidisciplinary Group meeting (MDGs are seen as key facilitators of integration, moving from individual to multi-disciplinary decision making, and from a focus on individual patients to a focus on patient groups.  We have developed a method for coding MDG transcripts to identify whether they are or are not vehicles for delivering the anticipated efficiency improvements across various providers and apply it to a test case in the North West London Integrated Care Pilot. Methods:  We defined 'integrating' as the process within the MDG meeting that enables or promotes an improved collaboration, improved understanding, and improved awareness of self and others within the local healthcare economy such that efficiency improvements could be identified and action taken.  Utterances within the MDGs are coded according to three distinct domains grounded in concepts from communication, group decision-making, and integrated care literatures - the Valence, the Focus, and the Level.  Standardized weighted integrative intensity scores are calculated across ten time deciles in the Case Discussion providing a graphical representation of its integrative intensity.Results: Intra- and Inter-rater reliability of the coding scheme was very good as measured by the Prevalence and Bias-adjusted Kappa Score.  Standardized Weighted Integrative Intensity graph mirrored closely the verbatim transcript and is a convenient representation of complex communication dynamics. Trend in integrative intensity can be calculated and the characteristics of the MDG can be pragmatically described.Conclusion: This is a novel and potentially useful method for researchers, managers and practitioners to better understand MDG dynamics and to identify whether participants are integrating.  The degree to which participants use MDG meetings to develop an integrated way of working is likely to require management, leadership and shared values.

  5. Molybdenite Re/Os dating, zircon U-Pb age and geochemistry of granitoids in the Yangchuling porphyry W-Mo deposit (Jiangnan tungsten ore belt), China: Implications for petrogenesis, mineralization and geodynamic setting

    Science.gov (United States)

    Mao, Jingwen; Xiong, Bikang; Liu, Jun; Pirajno, Franco; Cheng, Yanbo; Ye, Huishou; Song, Shiwei; Dai, Pan

    2017-08-01

    The Yangchuling W-Mo deposit, located in the Jiangnan porphyry-skarn (JNB) tungsten ore belt, is the first recognized typical porphyry W-Mo deposit in China in the 1980's. Stockworks and disseminated W-Mo mineralization occur in the roof pendant of a 0.3 km2 monzogranitic porphyry stock that intruded into a granodiorite stock, hosted by Neoproterozoic phyllite and slate. LA-ICPMS zircon U-Pb analyses suggest that of the monzogranitic porphyry and granodiorite were formed at 143.8 ± 0.5 Ma and 149.8 ± 0.6 Ma, respectively. Six molybdenite samples yielded a Re-Os weighted mean age of 146.4 ± 1.0 Ma. Geochemical data show that both granodiorite and monzogranitic porphyry are characterized by enrichment of large ion lithophile elements (LILE) relative to high field strength elements (HFSE), indicating a peraluminous nature (A/CNK = 1.01-1.08). Two granitoids are characterized by a negative slope with significant light REE/heavy REE fractionation [(La/Yb)N = 8.38-23.20] and negative Eu anomalies (Eu/Eu* = 0.69-0.76). The P2O5 contents of the Yangchuling granitoids range from 0.12% to 0.17% and exhibit a negative correlation with SiO2, reflecting that they are highly fractionated I-type. They have high initial 87Sr/86Sr ratios (0.7104-0.7116), low negative εNd(t) (- 5.05 to - 5.67), and homogeneous εHf(t) between - 1.39 and - 2.17, indicating similar sources. Additionally, two-stage Nd model ages (TDM2) of 1.3-1.4 Ga and two-stage Hf model ages (TDM2) of 1.2-1.3 Ga are consistent, indicating that Neoproterozoic crustal rocks of the Shuangqiaoshan Group could have contributed to form the Yangchuling magmas. Considering the two groups of parallel Late Mesozoic ore belts, namely the Jiangnan porphyry-skarn tungsten belt (JNB) in the south and the Middle-Lower Yangtze River porphyry-skarn Cu-Au-Mo-Fe ore belt (YRB) in the north, the Nanling granite-related W-Sn ore belt (NLB) in the south, the neighboring Qin-Hang porphyry-skarn Cu-Mo-hydrothermal Pb-Zn-Ag ore belt (QHB

  6. Trophodynamics and functional feeding groups of North Sea fauna: a combined stable isotope and fatty acid approach

    NARCIS (Netherlands)

    Kürten, B.; Frutos, I.; Struck, U.; Painting, S.J.; Polunin, N.V.C.; Middelburg, J.J.

    The trophodynamics of pelagic and benthic animals of the North Sea, North Atlantic shelf, were assessed using stable isotope analysis (SIA) of natural abundance carbon and nitrogen isotopes, lipid fingerprinting and compound-specific SIA (CSIA) of phospholipid-derived fatty acids (PLFAs).

  7. Trophodynamics and functional feeding groups of North Sea fauna: a combined stable isotope and fatty acid approach

    NARCIS (Netherlands)

    Kürten, B.; Frutos, I.; Struck, U.; Painting, S.J.; Polunin, N.V.C.; Middelburg, J.J.

    2013-01-01

    The trophodynamics of pelagic and benthic animals of the North Sea, North Atlantic shelf, were assessed using stable isotope analysis (SIA) of natural abundance carbon and nitrogen isotopes, lipid fingerprinting and compound-specific SIA (CSIA) of phospholipid-derived fatty acids (PLFAs).

  8. Direct Reduction of Iron Ore

    Science.gov (United States)

    Small, M.

    1981-04-01

    In the search for a pure, available iron source, steelmakers are focusing their attention on Directly Reduced Iron (DRI). This material is produced by the reaction of a low gangue iron ore with a hydrocarbonaceous substance. Commercially, DRI is generated in four different reactors: shaft (moving-bed), rotary kiln, fluidized bed, and retort (fixed-bed). Annual worldwide production capacity approaches 33 million metric tons. Detailed assessments have been made of the uses of DRI, especially as a substitute for scrap in electric furnace (EF) steelmaking. DRI is generally of a quality superior to current grades of scrap, with steels produced more efficiently in the EF and containing lower levels of impurities. However, present economics favor EF steel production with scrap. But this situation could change within this decade because of a developing scarcity of good quality scrap.

  9. Uranium ore processing in Spain

    International Nuclear Information System (INIS)

    Josa, J.M.

    1976-01-01

    The paper presents a review of the Spanish needs of uranium concentrates and uranium ore processing technology and trends in Spain. Spain produces approximately 200t U 3 O 8 /a at two facilities. One plant in the south (Andujar, Jaen) can obtain 70t U 3 O 8 /a and uses a conventional acid leaching process with countercurrent solvent extraction. A second plant, situated in the west (Ciudad Rodrigo, Salamanca) has started in 1975 and has a capacity of 120-130t U 3 O 8 /a, using acid heap leaching and solvent extraction. There is another experimental facility (Don Benito, Badajoz) scheduled to start in 1976 and expected to produce about 25-35t U 3 O 8 /a as a by-product of the research work. For the near future (1978) it is hoped to increase the production with: (a) A new conventional acid leaching/solvent extraction plant in Ciudad Rodrigo; its tentative capacity is fixed at 550t U 3 O 8 /a. (b) A facility in the south, to recover about 130t U 3 O 8 /a from phosphoric acid. (c) Several small mobile plants (30t U 3 O 8 /a per plant); these will be placed near small and isolated mines. The next production increase (1979-1980) will come with the treatment of sandstones (Guadalajara and Cataluna) and lignites(Cataluna); this is being studied. There are also research programmes to study the recovery of uranium from low-grade ores (heap, in-situ and bacterial leaching) and from other industries. (author)

  10. Genomic diversity and affinities in population groups of North West India: an analysis of Alu insertion and a single nucleotide polymorphism.

    Science.gov (United States)

    Saini, J S; Kumar, A; Matharoo, K; Sokhi, J; Badaruddoza; Bhanwer, A J S

    2012-12-15

    The North West region of India is extremely important to understand the peopling of India, as it acted as a corridor to the foreign invaders from Eurasia and Central Asia. A series of these invasions along with multiple migrations led to intermixture of variable populations, strongly contributing to genetic variations. The present investigation was designed to explore the genetic diversities and affinities among the five major ethnic groups from North West India; Brahmin, Jat Sikh, Bania, Rajput and Gujjar. A total of 327 individuals of the abovementioned ethnic groups were analyzed for 4 Alu insertion marker loci (ACE, PV92, APO and D1) and a Single Nucleotide Polymorphism (SNP) rs2234693 in the intronic region of the ESR1 gene. Statistical analysis was performed to interpret the genetic structure and diversity of the population groups. Genotypes for ACE, APO, ESR1 and PV92 loci were found to be in Hardy-Weinberg equilibrium in all the ethnic groups, while significant departures were observed at the D1 locus in every investigated population after Bonferroni's correction. The average heterozygosity for all the loci in these ethnic groups was fairly substantial ranging from 0.3927 ± 0.1877 to 0.4333 ± 0.1416. Inbreeding coefficient indicated an overall 10% decrease in heterozygosity in these North West Indian populations. The gene differentiation among the populations was observed to be of the order of 0.013. Genetic distance estimates revealed that Gujjars were close to Banias and Jat Sikhs were close to Rajputs. Overall the study favored the recent division of the populations of North West India into largely endogamous groups. It was observed that the populations of North West India represent a more or less homogenous genetic entity, owing to their common ancestral history as well as geographical proximity. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Last report of the United Nations Group of experts created in application of the resolution 1874: an update on the North-Korean proliferation crisis. Analysis note

    International Nuclear Information System (INIS)

    Germain, Timothee

    2013-01-01

    After having recalled the various resolutions issued by the UN Security Council to implement sanctions against North Korea after its nuclear and ballistic tests, the author comments the content of the last report issued by the group in charge of the implementation of resolutions number 1718 (of 2006) and 1874 (of 2009). The report first highlights the continuing efforts of North Korea in the nuclear and ballistic fields. These efforts are institutional and legal as well as practical with the construction of new installations and test sites as revealed by satellite images. They also have been studied with the examination of debris of a North-Korean rocket. Apart from that, the report described and outlined how North Korea remains an important actor of the trade of proliferation equipment. Recommendations made by the expert group are commented: they notably outline that the implementation of sanctions is complex and incomplete for various reasons related either to North Korean actions and behaviours, or to the process itself

  12. Silicic magmatism associated with Late Cretaceousrifting in the Arctic Basin – petrogenesis of the Kap Kane sequence, the Kap Washington Group volcanics, North Greenland

    DEFF Research Database (Denmark)

    Þórarinsson, Sigurjón Böðvar; Holm, Paul Martin; Duprat, Helene Inga

    2011-01-01

    The bimodal, Late Cretaceous–Palaeocene (71–61 Ma) Kap Washington Group volcanic sequence on the north coast of Greenland was erupted in a continental rift setting during the opening of the Arctic Ocean. On Kap Kane ca. 70 Ma silicic lavas and ignimbrites dominate over mildly alkaline basalts...

  13. Traffic safety issues in North Dakota : phase II : driver knowledge, attitude, behavior and beliefs : focus group : young male drivers

    Science.gov (United States)

    2008-10-01

    Traffic safety is a widespread social concern. Tackling the problem requires understanding the people : who are driving. This includes information about driver behavior, but also about perceptions these drivers : hold regarding their driving. North D...

  14. Modelling a uranium ore bioleaching process

    International Nuclear Information System (INIS)

    Chien, D.C.H.; Douglas, P.L.; Herman, D.H.; Marchbank, A.

    1990-01-01

    A dynamic simulation model for the bioleaching of uranium ore in a stope leaching process has been developed. The model incorporates design and operating conditions, reaction kinetics enhanced by Thiobacillus ferroxidans present in the leaching solution and transport properties. Model predictions agree well with experimental data with an average deviation of about ± 3%. The model is sensitive to small errors in the estimates of fragment size and ore grade. Because accurate estimates are difficult to obtain a parameter estimation approach was developed to update the value of fragment size and ore grade using on-line plant information

  15. Improved leaching process for metal ores

    International Nuclear Information System (INIS)

    Kar-Kwan Yung, K.; Barlow, C.B.; Glass, J.R.

    1980-01-01

    The general overall sequence of process steps in the technique of the invention in set forth. In sequence, the ore is crushed, and solubilizing reagents and moisture are added to the crushed ore in preselected controlled portions. The mixture of ore, reagent, and moisture is then cured followed in the preferred process by conditioning for filtration. The slurry that is produced from conditioning is then subjected to multiple stage washing on a belt filter. The filtrate is further processed for metal value recovery and the solids are transported to tailings disposal

  16. The well-being and personal wellness promotion strategies of medical oncologists in the North Central Cancer Treatment Group.

    Science.gov (United States)

    Shanafelt, Tait D; Novotny, Paul; Johnson, Mary E; Zhao, Xinghua; Steensma, David P; Lacy, Martha Q; Rubin, Joseph; Sloan, Jeff

    2005-01-01

    The well-being of oncologists is important to the well-being of their patients. While much is known about oncologist distress, little is known about oncologist well-being. We set out to evaluate oncologist well-being and the personal wellness promotion strategies used by oncologists. We performed a cross-sectional survey of medical oncologists in the North Central Cancer Treatment Group using a validated instrument to measure quality of life. Study-specific questions explored stressors, wellness promotion strategies and career satisfaction. Of 241 responding oncologists (response rate 61%), 121 (50%) reported high overall well-being. Being age 50 or younger (57 vs. 41%; p = 0.01), male (53 vs. 31%; p = 0.01) and working 60 h or less per week (50 vs. 33%; p = 0.005) were associated with increased overall well-being on bivariate analysis. Ratings of the importance of a number of personal wellness promotion strategies differed for oncologists with high well-being compared with those without high well-being. Developing an approach/philosophy to dealing with death and end-of-life care, using recreation/hobbies/exercise, taking a positive outlook and incorporating a philosophy of balance between personal and professional life were all rated as substantially more important wellness strategies by oncologists with high well-being (p values career satisfaction. Half of medical oncologists experience high overall well-being. Use of specific personal wellness promotion strategies appears to be associated with oncologist well-being. Further investigations of the prevalence, promotion, causes, inequities and clinical impact of physician well-being are needed. .

  17. Survey of Two New (Kai 1 and Kai 2) and Other Blood Groups in Dogs of North America.

    Science.gov (United States)

    Euler, C C; Lee, J H; Kim, H Y; Raj, K; Mizukami, K; Giger, U

    2016-09-01

    Based upon serology, >10 canine blood group systems have been reported. We surveyed dogs for dog erythrocyte antigen (DEA) 1 and 2 new blood types (Kai 1 and Kai 2), and some samples also were screened for Dal and DEA 3, 4, and 7. Blood samples provided by owners, breeders, animal blood banks, and clinical laboratories were typed for DEA 1 by an immunochromatographic strip technique with a monoclonal antibody and analysis of band intensity. Both new antigens, the Dal and other DEAs (except DEA 7 by tube method), were assessed by a gel column method with either monoclonal or polyclonal antibodies. The same gel column method was applied for alloantibody detection. Of 503 dogs typed, 59.6% were DEA 1+ with 4% weakly, 10% moderately, and 45.6% strongly DEA 1+. Regarding Kai 1 and Kai 2, 94% were Kai 1+/Kai 2-, 5% were Kai 1-/Kai 2- and 1% were Kai 1-/Kai 2+, but none were Kai 1+/Kai 2+. There was no relationship between Kai 1/Kai 2 and other blood types tested. Plasma from DEA 1-, Kai 1-, Kai 2- dogs, or some combination of these contained no detectable alloantibodies against DEA 1 and Kai 1 or Kai, respectively. The new blood types, called Kai 1 and Kai 2, are unrelated to DEA 1, 3, 4, and 7 and Dal. Kai 1+/Kai 2- dogs were most commonly found in North America. The clinical relevance of Kai 1 and Kai 2 in canine transfusion medicine still needs to be elucidated. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  18. Contact Dermatitis Associated With Skin Cleansers: Retrospective Analysis of North American Contact Dermatitis Group Data 2000-2014.

    Science.gov (United States)

    Warshaw, Erin M; Goodier, Molly C; DeKoven, Joel G; Maibach, Howard I; Taylor, James S; Sasseville, Denis; Belsito, Donald V; Fowler, Joseph F; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Mathias, Toby; Zirwas, Matthew J; Zug, Kathryn A

    There is limited information regarding contact dermatitis (CD) associated with skin cleansers (SCs). The aim of the study was to evaluate the prevalence of allergic patch test (APT) reactions and irritant CD (ICD) associated with SCs. A retrospective cross-sectional analysis was performed using North American Contact Dermatitis Group data, 2000-2014. Of 32,945 tested patients, 1069 (3.24%) had either APT reaction or ICD associated with SCs. Of these, 692 (64.7%) had APT reaction only, 350 (32.7%) had ICD only, and 27 (2.5%) had both. Individuals with APT reaction and/or ICD were more likely to have occupationally related skin disease (relative risk [RR] = 3.8 [95% confidence interval {CI} = 3.3-4.5] for APT reaction and 10.0 [95% CI = 8.2-12.2] for ICD, respectively, P dermatitis (RR = 1.3 [95% CI = 1.1-1.6], P ≤ 0.001). Irritant CD was strongly associated with hand dermatitis (RR = 6.2 [95% CI = 5.2-7.3], P < 0.0001). More than 50 allergens were associated with SCs including quaternium-15 (11.2%), cocamidopropyl betaine (9.5%), methylchloroisothiazolinone/methylisothiazolinone (8.4%), coconut diethanolamide (7.9%), fragrance mix I (7.7%), Myroxylon pereirae (5.9%), 4-chloro-3,5-xylenol (5.8%), amidoamine (5.5%), and formaldehyde (4.4%). Many allergens, especially preservatives and surfactants, were associated with SCs. Most cases involved the hands and were occupationally related.

  19. Structure and texture of uranium ores in exogenous deposits

    International Nuclear Information System (INIS)

    Danchev, V.I.

    1977-01-01

    Structure and texture signs of uranium rock exogenous deposits have been systematized for the first time, taking into account the slaging of the ore-formation process, connected with formation and change of containing sedimentary rocks, starting with the sedimentogenesis stage and early sediment diagenesis and their subsequent transformation in katagenesis and metamorphism processes. The main features of uranium geochemistry in the exogenous process are considered. Suggested is the genetic classification of uranium exogenous deposits in rocks of sedimentary cover, made with respect to conjugation and various ore-forming productivity of the litogenesis stage. Described are the main combinations of various rock texture and structure properties, characteristic of deposits of genetic classes and groups of the above classification. Eight most frequently occuring textures (lamellar, concretion, oolitic, coagulate, crack, mixed and impregnated) and their types are described and illustrated. Materials of soviet and foreign authors have been used to compile the atlas

  20. Uranium ore deposits: geology and processing implications

    International Nuclear Information System (INIS)

    Belyk, C.L.

    2010-01-01

    There are fifteen accepted types of uranium ore deposits and at least forty subtypes readily identified around the world. Each deposit type has a unique set of geological characteristics which may also result in unique processing implications. Primary uranium production in the past decade has predominantly come from only a few of these deposit types including: unconformity, sandstone, calcrete, intrusive, breccia complex and volcanic ones. Processing implications can vary widely between and within the different geological models. Some key characteristics of uranium deposits that may have processing implications include: ore grade, uranium and gangue mineralogy, ore hardness, porosity, uranium mineral morphology and carbon content. Processing difficulties may occur as a result of one or more of these characteristics. In order to meet future uranium demand, it is imperative that innovative processing approaches and new technological advances be developed in order that many of the marginally economic traditional and uneconomic non-traditional uranium ore deposits can be exploited. (author)

  1. Filtration aids in uranium ore processing

    International Nuclear Information System (INIS)

    Ford, H.L.; Levine, N.M.; Risdon, A.L.

    1975-01-01

    The patent describes a process whereby improved flocculation efficiency and filtration of carbonate leached uranium ore pulps are obtained by treating the filter feed slurry with an aqueous solution of hydroxyalkyl guar. (J.R.)

  2. Uranium extraction from gold-uranium ores

    Energy Technology Data Exchange (ETDEWEB)

    Laskorin, B.N.; Golynko, Z.Sh.

    1981-01-01

    The process of uranium extraction from gold-uranium ores in the South Africa is considered. Flowsheets of reprocessing gold-uranium conglomerates, pile processing and uranium extraction from the ores are presented. Continuous counter flow ion-exchange process of uranium extraction using strong-active or weak-active resins is noted to be the most perspective and economical one. The ion-exchange uranium separation with the succeeding extraction is also the perspective one.

  3. Natural resources sustainability: iron ore mining

    International Nuclear Information System (INIS)

    De La Torre de Palacios, Luis

    2011-01-01

    In the present article, a new tool to determine environmental sustainability, the energy impact index (EII) was developed to classify different iron mine projects according to two main parameters including energy consumption and CO 2 emissions. The EII considers the characteristics of the mineral (such as the quality, size, hardness, iron ore grade, reducibility, mineral/waste rate, and type of deposit), mining processes (type of exploitation, ore processing, available technology), and transportation (distance to cover).

  4. Determination of gold in gold ores

    International Nuclear Information System (INIS)

    Keedy, C.R.; Parson, L.; Shen, J.

    1989-01-01

    The gold content of placer gold flakes and gold bearing ores was determined by instrumental and radiochemical neutron activation analysis, respectively. It was discovered that significant errors result in the instrumental method for gold flakes as small as 10 mg due to sample self-absorption of neutrons during irradiation. Reliable results were obtained for both ore samples and gold flakes by dissolving the samples in aqua regia prior to irradiation. (author) 7 refs.; 3 tabs

  5. Uranium ore processing minimizing reagent losses

    International Nuclear Information System (INIS)

    Shaogiang, Chen; Moret, J.; Lyaudet, G.

    1989-01-01

    The uranium ore is treated by sodium carbonates and the solution is divided in two parts: a production solution which is decarbonated by an acid before uranium precipitation with sodium hydroxide and a recycling solution directly treated by sodium hydroxide for precipitation of about 85% of uranium and total transformation of sodium bicarbonate into sodium carbonate, the quantity of sodium hydroxide used on the recycling solution brings sodium ions required for attack of the ore [fr

  6. Decomposition of aluminosilicate ores of Afghanistan by hydrochloric acid

    International Nuclear Information System (INIS)

    Mamatov, E.D.; Khomidi, A.K.

    2015-01-01

    Present article is devoted to decomposition of aluminosilicate ores of Afghanistan by hydrochloric acid. The physicochemical properties of initial aluminosilicate ores were studied by means of X-ray phase, differential-thermal analysis methods. The chemical and mineral composition of aluminosilicate ores was considered. The kinetics of acid decomposition of aluminosilicate ores composed of two stages was studied as well. The flowsheets of complex processing of aluminium comprising ores by means of chloric and acid methods were proposed.

  7. Ores and Climate Change - Primary Shareholders

    Science.gov (United States)

    Stein, Holly J.; Hannah, Judith L.

    2015-04-01

    Many in the economic geology community concern themselves with details of ore formation at the deposit scale, whether tallying fluid inclusion data to get at changes in ore-forming fluids or defining structures that aid and abet mineralization. These compilations are generally aimed at interpretation of events at the site of ore formation, with the goal being assignment of the deposit to a sanctioned ore deposit model. While providing useful data, this approach is incomplete and does not, by itself, serve present-day requirements for true interdisciplinary science. The ore-forming environment is one of chaos and disequilibrium at nearly all scales (Stein, 2014). Chaos and complexity are documented by variably altered rocks, veins or disseminated mineralization with multi-generational fluid histories, erratic and unusual textures in host rocks, and the bitumen or other hydrocarbon products entwined within many ore deposits. This should give pause to our drive for more data as a means to find "the answer". The answer lies in the kind of data collected and more importantly, in the way we interpret those data. Rather than constructing an ever-increasing catalog of descriptive mutations on sanctioned ore deposit models (e.g., IOGC or Iron-Oxide Copper Gold deposits), the way forward is to link source and transport of metals, sulfur, and organic material with regional and ultimately whole Earth chemical evolution. Important experimental work provides chemical constraints in controlled and behaved environments. To these data, we add imagination and interpretation, always tying back to field observations. In this paper, several key points are made by way of ore deposit examples: (1) many IOCG deposits are outcomes of profound changes in the chemistry of the Earth's surface, in the interplay of the atmosphere, hydrosphere, biosphere, and lithosphere; (2) the redox history of Fe in deep earth may be ultimately expressed in the ore-forming sequence; and (3) the formation of

  8. Technical and economic benefits of nuclear techniques in ore processing

    International Nuclear Information System (INIS)

    1989-08-01

    This report is the outcome of an Advisory Group Meeting organized by the Agency and hosted by the Institute of Physics and Nuclear Techniques, the Academy of Mining and Metallurgy in Krakow, Poland. The purpose of the meeting was to assess the technical and economic benefits of applying nuclear techniques in ore processing industry. Nucleonic control systems and nuclear on-line analytical techniques as well as radioisotope tracer tests and their applications in metallic ore-processing, coal production, and cement fabrication were discussed. This report contains a summary and the presentations dealing with nuclear techniques for process control made at this meeting. Using a number of case-histories as examples, it illustrates technical and economic benefits obtainable by the installation of nuclear process control instrumentation. It is expected to be useful for everybody dealing with ore and coal production, but especially for administrative personnel and engineers who plan and implement national development programmes related to mineral resources. Refs, figs and tabs

  9. Ore-lead isotopes and Grenville plate tectonics

    International Nuclear Information System (INIS)

    Farquhar, R.M.; Fletcher, I.R.

    1980-01-01

    Recent advances in the 'whole earth' modelling of evolutionary processes of Pb isotopes shed light upon the origin of the metals found in various types of ore deposits. On the bases of these models and several recently published data sets, we believe that the ore deposits formed in various plate tectonic environments may carry 'isotopic fingerprints' which, when used with other characteristics such as mineral assemblages, may identify the depositional environments of many ore bodies. In the present study Pb-isotopic measurements have been made of a number of Precambrain mineralization types and localities throughout the Central Metasedimentary Belt of the Grenville Province. The data for individual deposits are at best ambiguous, but fall into two groups sufficiently distinctive to allow some degree of 'fingerprint' identification. Comparisons with data from other areas suggest that the major periods of sedimentation within the Central Metasedimentary Belt accompanied plate rifting and/or island arc tectonic activity, with most of the mineralized lead being derived from mantle sources. Detailed comparisons between the Grenville and other regions are uncertain, mainly because there are few detailed high-accuracy data sets from younger, tectonically unambiguous mineral occurrences. We suggest that once these data sets are availble, isotopic fingerprinting may become diagnostic for deposits ranging well back into the Precambrain

  10. Radioisotope devices at Novo-Krivorozhskij-ore-enrichment plant

    International Nuclear Information System (INIS)

    Levitskij, V.Ya.; Kucher, V.G.; Ministerstvo Chernoj Metallurgii Ukrainskoj SSR, Dnepropetrovsk, Bazovaya Opytno-Konstruktorskaya Izotopnaya lab.)

    1975-01-01

    Use of the ''Ferrite'' analyzers, AZhR and PAZh-1 and the GR-7 gamma relay in different engineering areas of the Novo-Krivorozh ore-enrichment plant is evaluated. The ''Ferrite'' radioisotopic analyzer was designed for rapid roentgeno-radiometric determination of the total iron and iron group element contents in powdered samples of ores and products of their treatment. From the density of the flux of the characteristic radiation it is possible to determine quantitatively the content of the element of interest in the analyzed material. The radioisotpic analyzer AZhR-1 is distinguished by its high efficiency in the analysis for total iron on products of processing of iron ore raw materials. The use of this apparatus allows complete replacement of the chemical method for rapid analysis of concentrates by the roentgeno-radiometric method, which decreases the total analytical work on determination of total iron and speeds up output of information on concentrate quality. The radioisotopic gamma analyzer PAZh-1 is designed for automatic and either continuous or discrete measurement of the total iron content in iron ore materials ground to 50 mm, carried on a conveyor, without selection or preparation of the samples for analysis. The analyzer operates on the principle of measuring the average frequency of impingement on a detector of gamma quanta back-scattered by the analyzed material. This frequency is determined by the percentage content of total iron in the material. The apparatus operates continuously. The mean square deviation of the apparatus values from chemical data is 0.93% Fesub(total). Use of the apparatus greatly increases the operativeness of the control and decreases the laboriousness of raw material sampling in an engineering stream. The radioisotopic data units GR-7 are designed for control of the level of materials in hoppers for recovery and burning of agglomerates. Use of this apparatus showed its great advantage over data units of other types

  11. Ladinian skonca beds of the Idrija Ore Deposit (W Slovenia

    Directory of Open Access Journals (Sweden)

    Jože Čar

    2013-12-01

    Full Text Available The richly mineralised Skonca beds (der Lagerschiefer were the most important mining level of the Idrija ore deposit. In addition to epigenetic ores, exceptional quantities of various rich syngenetic cinnabar ores could be found in these layers. »Jeklenka« (steel ore, »opekovka« (brick ore, »jetrenka« (liver ore, coral ore, and some other bedded cinnabar ores contained up to as much as 78 % Hg. These ores were excavated more or less intensively from their discovery in 1508 until the cessation of works in the Idrija Mine in 1977. The Skonca beds can be found in all parts of the Idrija ore deposit in the form of large or small, irregular, lenseshaped bodies or layers. In the section of the ore deposit known as šTalnina’, the Skonca beds are on average only 4 m thick, and from 10 to maximally 25 m in other parts of the ore deposit. The greatest thickness of these beds, i.e. around 40 m, can be found in the area of the Karóli tectonic unit, situated in the deepest part of the former Idrija Middle Triassic tectonic fault trough. The rocks in the Skonca beds are grouped in typical sequences, which represent a key for the reconstruction of sedimentary environments. The sequences are designated with the letters A, B, C and D. Sequence C is further divided into subsequences C1 with a carbonate and C2 with a siliceous structure. The lithological units of sequence A usually represent the lowest part of the Skonca beds, and may be the lateral equivalents of rocks of series B and subsequence C1. Sequence A is comprised of dispersed, gravelly varieties of carbonatic lythic sandstone, limestone and dolomite siltstone, as well as intercalations of gravelly silty micritic limestone and micritic limestone. Sequence B consists of typical transitional rocks between sequences A and C1, among which silty limestone with transitions to calcitic marlstone and claystone can be found. Sequence C is formed of šclassic’ Skonca rock beds. Although the bottom

  12. Influence of acid/ore relation in the uranium-silicate ore treatment

    International Nuclear Information System (INIS)

    Antaki, C.; Cipriani, M.; Bruno, J.B.

    1985-01-01

    The estimation of acid addition effect (Kg of H 2 SO 4 /t of ore) in uranium extraction from an uranium-silicate ore, with a view to the control of silica concentration in leach under 0,6 g/l is presented. The analysis was effected based on bench-scale tests, with different quantities of sulfuric acid addition. (Author) [pt

  13. Norwegian 1990 sediment data for the North Sea Task Force (NSTF) and the Joint Monitoring Group (JMG)

    Energy Technology Data Exchange (ETDEWEB)

    Green, N.W.; Klungsoeyr, J.

    1994-12-31

    This report presents the 1990 sediment data compiled as part of the Norwegian contribution to the North Sea Task Force Monitoring Master Plan and the Joint Monitoring Programme (JMP). The JMP is ordered under the Oslo and Paris Commissions, which were established to protect the marine environment against anthropogenic contamination. The stations monitored by Norway are spread over the Kattegat, Skagerrak, North Sea south to the Dogger Bank and the Faeroe Islands. The contaminants investigated are mainly selected metals, organochlorines, polycyclic aromatic hydrocarbons, and the samples were collected by gravity cores and grab/box samplers. The raw data and the mean and standard deviations of parallel samples (if relevant) are presented. 6 refs., 2 tabs.

  14. Metal sources in Jurassic to miocene ore deposits of Ecuador

    International Nuclear Information System (INIS)

    Chiaradia, M.; Fontbote, L

    2001-01-01

    The Ecuadorian crust is a mosaic of NNE-SSW-trending terranes representing different geotectonic domains. These terranes, composed by oceanic and continental crust, were formed during the Triassic separation of the North and South American continents and were accreted to the Amazon craton during subduction of the Farallon/Nazca plate, from Early Cretaceous to Early Tertiary (Litherland et al., 1994). In the southwestern part of Ecuador, EW-striking crustal-scale faults, related to the Huancabamba deflection, mark the transition between the Central and Northern Andes. In this study we discuss more than 200 lead isotope compositions of ores as well as magmatic and metamorphic rocks of Ecuador. The interest of carrying out a large-scale isotope survey in the Northern Andes derives from a geotectonic evolution characterized by multi-accretionary episodes which is not recognized in the Central Andes (au)

  15. Economic evaluation of preconcentration of uranium ores

    International Nuclear Information System (INIS)

    1981-04-01

    The economics of two options for the preconcentration of low-grade uranium ores prior to hydrochloric acid leaching were studied. The first option uses flotation followed by wet high-intensity magnetic separation. The second option omits the flotation step. In each case it was assumed that most of the pyrite in the ore would be recovered by froth flotation, dewatered, and roasted to produce sulphuric acid and a calcine suitable for acid leaching. Savings in operating costs from preconcentration are offset by the value of uranium losses. However, a capital saving of approximately 6 million dollars is indicated for each preconcentration option. As a result of the capital saving, preconcentration appears to be economically attractive when combined with hydrochloric acid leaching. There appears to be no economic advantage to preconcentration in combination with sulphuric acid leaching of the ore

  16. Radiometric sorting of Rio Algom uranium ore

    International Nuclear Information System (INIS)

    Cristovici, M.A.

    1983-11-01

    An ore sample of about 0.2 percent uranium from Quirke Mine was subjected to radiometric sorting by Ore Sorters Limited. Approximately 60 percent of the sample weight fell within the sortable size range: -150 + 25 mm. Rejects of low uranium content ( 2 (2 counts/in 2 ) but only 7.6 percent of the ore, by weight, was discarded. At 0.8-0.9 counts/cm 2 (5-6 counts/in 2 ) a significant amount of rejects was removed (> 25 percent) but the uranium loss was unacceptably high (7.7 percent). Continuation of the testwork to improve the results is proposed by trying to extend the sortable size range and to reduce the amount of fines during crushing

  17. Uranium accompanying recovery from copper ores

    International Nuclear Information System (INIS)

    Golynko, Z.Sh.; Laskorin, B.N.

    1981-01-01

    In the search for new raw material sources for nuclear power engineering a review of the technique of uranium accompaning recovery from copper ores reprocessing products in some countries is presented. In the USA a sorption method of uranium extraction by means of strongly basic ion exchange resins from solutions upon copper case- hardening with subsequent extraction from eluates by solutions of tertiary amines is realized. Elution is realized with sulphuric acid. In South Africa an extraction reprocessing of gravitational concentrate extracted from copper sulphide flotation tailings is organized. In India the uranium extraction from copper ores flotation enrichment tailings is organized on a commerical scale. Presented are data on the scale of uranium recovery, various conditions of its recovery as well as block diagrams of the processes. It is shown that copper ores become an additional source of uranium recovery [ru

  18. Mining of sedimentary-type ore deposits

    International Nuclear Information System (INIS)

    Bruha, J.; Slovacek, T.; Berka, J.; Sadilek, P.

    1992-01-01

    A procedure is proposed for mining sedimentary-type ore deposits, particularly uranium deposits, using the stope-pillar technique. The stope having been mined out, the free room is filled with hydro-setting gob from the surface. A precondition for the application of this technique is horizontal ore mineralization in sediments where the total thickness of the mineralized ore layer is at least 3 to 5 m. Mining losses do not exceed 5%. For thicknesses greater than 5 m, the roof is reinforced and the walls are secured with netting. The assets of the technique include higher labor productivity of the driving, lower material demands in reinforcing and filling, lower power consumption, and reduced use of explosives. (Z.S.). 3 figs

  19. Polyphyly of the Padus group of Prunus (Rosaceae) and the evolution of biogeographic disjunctions between eastern Asia and eastern North America.

    Science.gov (United States)

    Liu, Xiao-Lin; Wen, Jun; Nie, Ze-Long; Johnson, Gabriel; Liang, Zong-Suo; Chang, Zhao-Yang

    2013-05-01

    Prunus subgenus Padus is a group with a wide distribution in temperate eastern Asia and eastern North America with one species extending to Europe and one to Central America. Phylogenetic relationships of subgenus Padus were reconstructed using sequences of nuclear ribosomal ITS, and plastid ndhF gene, and rps16 intron and rpl16 intron. Prunus subgenus Padus is shown to be polyphyletic. Taxa of subgenus Padus and subgenus Laurocerasus are highly intermixed in both the ITS and the plastid trees. The results support two disjunctions between eastern North America and Eurasia within the Padus group. One disjunction is between Prunus virginiana of eastern North America and P. padus of Eurasia, estimated to have diverged at 2.99 (95 % HPD 0.59-6.15)-4.1 (95 % HPD 0.63-8.59) mya. The other disjunction is between P. serotina and its Asian relatives. The second disjunction may have occurred earlier than the former one, but the age estimate is difficult due to the unresolved phylogenetic position of the P. serotina complex.

  20. Geochemical features of the ore-bearing medium in uranium deposits in the Khiagda ore field

    Science.gov (United States)

    Kochkin, B. T.; Solodov, I. N.; Ganina, N. I.; Rekun, M. L.; Tarasov, N. N.; Shugina, G. A.; Shulik, L. S.

    2017-09-01

    The Neogene uranium deposits of the Khiagda ore field (KOF) belong to the paleovalley variety of the hydrogene type and differ from other deposits of this genetic type in the geological and geochemical localization conditions. The contemporary hydrogeochemical setting and microbiological composition of ore-bearing medium are discussed. The redox potential of the medium (Eh is as low as-400 mV) is much lower than those established at other hydrogenic deposits, both ancient Late Mesozoic and young Late Alpine, studied with the same methods in Russia, Uzbekistan, and southern Kazakhstan. The pH of subsurface water (6.86-8.13) differs in significant fluctuations both between neighboring deposits and within individual ore lodes. Hydrogen-forming and denitrifying bacteria are predominant in microbiological populations, whereas sulfate-reducing bacteria are low-active. The consideration of these factors allowed us to describe the mechanism of uranium ore conservation as resulting from the development of the cryolithic zone, which isolates ore lodes from the effect of the external medium. Carbonated water supplied from the basement along fault zones also participates in the formation of the present-day hydrogeochemical setting. Based on the features of the ore-bearing medium, we propose a method of borehole in situ acid leaching to increase the efficiency of mining in the Khiagda ore field.

  1. Uranium abundance in some sudanese phosphate ores

    International Nuclear Information System (INIS)

    Adam, A.A.; Eltayeb, M.A.H.

    2009-01-01

    This work was carried out mainly to analysis of some Sudanese phosphate ores, for their uranium abundance and total phosphorus content measured as P 2 O 5 %. For this purpose, 30 samples of two types of phosphate ore from Eastern Nuba Mountains, in Sudan namely, Kurun and Uro areas were examined. In addition, the relationship between uranium and major, and trace elements were obtained, also, the natural radioactivity of the phosphate samples was measured, in order to characterize and differentiate between the two types of phosphate ores. The uranium abundance in Uro phosphate with 20.3% P 2 O 5 is five time higher than in Kurun phosphate with 26.7% P 2 O 5 . The average of uranium content was found to be 56.6 and 310 mg/kg for Kurun and Uro phosphate ore, respectively. The main elements in Kurun and Uro phosphate ore are silicon, aluminum, and phosphorus, while the most abundant trace elements in these two ores are titanium, strontium and barium. Pearson correlation coefficient revealed that uranium in Kurun phosphate shows strong positive correlation with P 2 O 5 , and its distribution is essentially controlled by the variations of P2O5 concentration, whereas uranium in Uro phosphate shows strong positive correlation with strontium, and its distribution is controlled by the variations of Sr concentration. Uranium behaves in different ways in Kurun phosphate and in Uro phosphate. Uro phosphate shows higher concentrations of all the estimated radionuclides than Kurun phosphate. According to the obtained results, it can be concluded that Uro phosphate is consider as secondary uranium source, and is more suitable for uranium recovery, because it has high uranium abundance and low P 2 O 5 %, than Kurun phosphate. (authors) [es

  2. The physical hydrogeology of ore deposits

    Science.gov (United States)

    Ingebritsen, Steven E.; Appold, M.S.

    2012-01-01

    Hydrothermal ore deposits represent a convergence of fluid flow, thermal energy, and solute flux that is hydrogeologically unusual. From the hydrogeologic perspective, hydrothermal ore deposition represents a complex coupled-flow problem—sufficiently complex that physically rigorous description of the coupled thermal (T), hydraulic (H), mechanical (M), and chemical (C) processes (THMC modeling) continues to challenge our computational ability. Though research into these coupled behaviors has found only a limited subset to be quantitatively tractable, it has yielded valuable insights into the workings of hydrothermal systems in a wide range of geologic environments including sedimentary, metamorphic, and magmatic. Examples of these insights include the quantification of likely driving mechanisms, rates and paths of fluid flow, ore-mineral precipitation mechanisms, longevity of hydrothermal systems, mechanisms by which hydrothermal fluids acquire their temperature and composition, and the controlling influence of permeability and other rock properties on hydrothermal fluid behavior. In this communication we review some of the fundamental theory needed to characterize the physical hydrogeology of hydrothermal systems and discuss how this theory has been applied in studies of Mississippi Valley-type, tabular uranium, porphyry, epithermal, and mid-ocean ridge ore-forming systems. A key limitation in the computational state-of-the-art is the inability to describe fluid flow and transport fully in the many ore systems that show evidence of repeated shear or tensional failure with associated dynamic variations in permeability. However, we discuss global-scale compilations that suggest some numerical constraints on both mean and dynamically enhanced crustal permeability. Principles of physical hydrogeology can be powerful tools for investigating hydrothermal ore formation and are becoming increasingly accessible with ongoing advances in modeling software.

  3. Methodological approach of the North-Cotentin radioecological group in charge of the evaluation of doses and risks due to the radiations exposure of the North-Cotentin population

    International Nuclear Information System (INIS)

    Sugierr, A.

    1999-01-01

    The group has evaluated and validated the list and quantities of radioelements release(source term) for each of the four nuclear installations of the North Cotentin since their beginning of operation (the reprocessing plant of Cogema la Hague, the Flamanville nuclear power plant, the Manche storage plant and the arsenal of the Cherbourg harbour). The gathering of data relative to radionuclides in environment of the north Cotentin has allowed from one hand the publication of samples inventory and types of radioactivity measurements and in an other hand an analysis of the results. The intercomparison of transfer models in environment and the confrontation of their results with the measures have been used for the doses calculations to the references groups and to the children troop from the Beaumont-Hague district. Finally, the elements necessary to the doses and risks estimation have been itemized and validated. One of the questions that stands out of these works is this one of the aims of the surveillance and measurements in environment according to the different organisms that realize them. It is important to make the distinction between the routine measurements ( to be sure of the correct operation of the facility and that the authorized release limits are well respected) and the measurements that allow to reconstitute the dose to population groups. (N.C.)

  4. Effective Processing of the Iron Ores

    Science.gov (United States)

    Kuskov, Vadim; Kuskova, Yana; Udovitsky, Vladimir

    2017-11-01

    Effective technology for a complex wasteless processing of the iron ores has been designed and includes three main components (plats): comminution plant, briquette plant, pigment plant. The comminution is done per energy effective technology. Using of briquetting for ores clotting enables the costs cut and brings to a higher level of environmental safety of the process. Briquette formation can be done as a regular pressing, as an extrusion. Developed technology allows to produce high quality competitively products for metallurgy industry and red iron oxide pigments. The whole production line impacts the environment in a minimal manner.

  5. Effective Processing of the Iron Ores

    Directory of Open Access Journals (Sweden)

    Kuskov Vadim

    2017-01-01

    Full Text Available Effective technology for a complex wasteless processing of the iron ores has been designed and includes three main components (plats: comminution plant, briquette plant, pigment plant. The comminution is done per energy effective technology. Using of briquetting for ores clotting enables the costs cut and brings to a higher level of environmental safety of the process. Briquette formation can be done as a regular pressing, as an extrusion. Developed technology allows to produce high quality competitively products for metallurgy industry and red iron oxide pigments. The whole production line impacts the environment in a minimal manner.

  6. Application of biohydrometallurgy to uranium ore processing

    International Nuclear Information System (INIS)

    Zhang Jiantang

    1989-01-01

    The development on application of biohydrometallargy to uranium ore processing is briefly introduced. The device designed for oxidizing ferrous ions in solution by using biomembrane, several bacterial leaching methods and the experimental results are given in this paper. The presented biohydrometallurgical process for recovering uranium includes bacterial leaching following by adsorption using tertiary amine resin 351 and oxidation of ferrous ions in the device with biomembranes. This process brings more economical benefits for treating silicate type original ores. The prospects on application of biogydrometallyurgy to solution mining is also discussed

  7. Status Report from Czechoslovakia [Processing of Low-Grade Uranium Ores

    Energy Technology Data Exchange (ETDEWEB)

    Civin, V; Belsky, M [Research and Development Laboratory No.3 of the Uranium Industry, Prague, Czechoslovakia (Czech Republic)

    1967-06-15

    The present paper deals with the fundamental problems and the main routes followed in processing low-grade uranium ores in CSSR. In this connection it may be useful to discuss the definition of low-grade ore. In our country this term is applied to uraniferous material with a very low content of uranium (of the order of 0.01%) whose treatment causes no particular difficulty. However, the same term is also used to designate those materials whose processibility lies on the verge of economic profitability. In our view, this classification, of an ore using two independent criteria (i.e. uranium content and processing economy) is useful from the standpoint of technology. The treatment of both such ore types is as a rule carried out by specific technological processes. Consequently, low-grade uranium ores can be divided into two groups: (1) Ores with a low uranium content. To this category belong in our country uraniferous materials which originate as a by-product of technological processes used in processing other materials. This is primarily gangue and tailings of various physical or physico-chemical pretreatment operations to which the ore is subjected at the mining site. Mention should be made in this connection of mine waters, which represent a useful complementary source of uranium despite their low uranium content (of the order of milligrams per litre). (2) Ores whose economical treatment is problematic. To this category belong deposits of conventional ore types with a uranium content on the limit of profitable treatment. Also, those deposits containing atypical materials possessing such properties which impair the economy of their treatment. This includes ores with a considerable amount of components which are difficult to separate and which at the same time consume the leaching agents. Finally, it covers uranium-bearing materials in refractory forms which are difficult to dissolve and also some special materials, such as lignites, uranium-bearing shales, loams

  8. Practice and prospect on bioleaching of uranium ore in China

    International Nuclear Information System (INIS)

    Liu Jian; Fan Baotuan; Meng Yunsheng; Zheng Ying; Liu Chao; Zhou Lei

    2008-01-01

    Developing situation on bioleaching of uranium ore in China is introduced. The selection and domestication of bacteria, development and application of biocntact oxidation tank, and practice on bioleaching of uranium ore in China are retrospeted and prospected. (authors)

  9. Measurement and Modelling of Blast Movement to Reduce Ore ...

    African Journals Online (AJOL)

    user

    geologists at Newmont Ahafo Mine have realised the impact of blast movement on ore losses and dilution and have ... Movement to Reduce Ore Losses and Dilution at Ahafo Gold Mine in Ghana”, Ghana Mining Journal, pp. .... classification.

  10. Flocculation of chromite ore fines suspension using polysaccharide ...

    Indian Academy of Sciences (India)

    Unknown

    liquid separation. Keywords. Flocculation; graft copolymer; mineral industry effluent; chromite ore fines; ... work well as flocculating agent on coal washery effluent, copper and iron ore fines etc (Karmakar et al 1998, 1999;. Tripathy et al 2001).

  11. Geophysical prospecting for iron ore deposit around Tajimi village, Lokoja, North–Central Nigeria

    Directory of Open Access Journals (Sweden)

    Bayowa Oyelowo

    2016-09-01

    Full Text Available Ground magnetic and electrical resistivity survey were undertaken to investigate the occurrence and geometry of iron ore deposit around Tajimi village, Lokoja, North-Central Nigeria. The generated residual map of the ground-magnetic data acquired at 250 stations along 15 traverses revealed numerous prominent anomalies, mostly trending in the N-S direction. The radial power spectrum revealed the depth to magnetic sources between 6 m to 20 m. The interpreted VES data characterized the area into three subsurface layers: top soil, presumably iron ore layer and weathered/fresh basement. The result of vertical electrical sounding curves showed a sudden drop in resistivity (42-241 Ωm over high magnetic response. The geo-electric section revealed that the study area is generally characterized with thin overburden (0.5-1.7 m and the thickness of the second layer (presumed to be the iron ore layer ranged between 6.2-25.1 m. The study concluded that areas of high magnetic intensity showed a sudden drop in resistivity value for the VES points, which give an indication of the presence of an electrically conductive structure presumed to be iron ore deposits.

  12. X-ray radiometric method of ore quality monitoring during mining

    International Nuclear Information System (INIS)

    Ivanyukovich, G.A.

    1979-01-01

    The method is basically applied for sampling ore deposits, mainly of nonferrous and rare metals. It can be used for determining one, two or three elements in the deposit. In the USSR, the method has so far been used in Far East tin deposits and in the North Caucasus tungsten-molybdenum deposit. It is used for the analysis of boreholes, shaft walls, mined ore and ore material intended for enriching. The instruments used include single-channel gamma spectrometers using scintillation or proportional counters as detectors. Logging instruments include dual-channel spectrometers featuring automatic gain control and data processing devices. The instruments are designed for separating elements with atomic numbers 19 to 88 from mine wall materials and with atomic numbers 26 to 88 in boreholes at concentrations exceeding 0.1% and 0.01% for tin and silver, respectively. The economic benefit is shown of the introduction of the method using the Sadon lead-zinc plant and Khrustalnensk ore treatment plant as examples. (H.S.)

  13. Heap leaching of clay ish uranium ores

    International Nuclear Information System (INIS)

    Gonzalez, E.; Sedano, A.

    1973-01-01

    This paper describes an experimental facility, built near El Lobo mine. In it we study the beneficiation of low-grade uranium ore. The mineral has a great amount of clay and fines. The flow-sheet used has four steps: head leaching, ph-ajustement, ion-exchange and participation. We show, also, the most interesting results. (Author)

  14. Bacterial leaching of pyritic gold ores

    International Nuclear Information System (INIS)

    Gagliardi, F.M.; Cashion, J.D.; Brown, J.; Jay, W.H.

    1998-01-01

    Full text: Pyritic ores (pyrite and arsenopyrite) containing gold concentrations in excess of 50g Au/t can be processed to recover the gold by the removal of the sulphur from the ore. This may be achieved by roasting (producing sulphur dioxide emissions), pressure oxidation (expensive and suitable for large high grade deposits), pressure leaching (still currently being developed) or bacterial oxidation. The bacterial oxidation process is a well known process in nature but has only recently come under investigation as a economically viable and relatively clean method of gold recovery from deep low grade sulphidic ores. Samples were obtained from the Wiluna Gold Mine in Western Australia consisting of the original ore, six successive bacterial reactors and the final products. Moessbauer experiments have been performed at room temperature, liquid nitrogen and liquid helium temperatures, and in applied magnetic fields. The main components of the iron phases which were present during the bacterial treatment were pyrite and arsenopyrite which were readily oxidised by the bacteria. Ferric sulfates and ferric arsenates were identified as by-products of the process with a small amount of the oxyhydroxide goethite. These results are in contrast to the similar study of the Fairview Mine in South Africa where principally Fe(II) species were observed

  15. PROCESS OF RECOVERING URANIUM FROM ITS ORES

    Science.gov (United States)

    Galvanek, P. Jr.

    1959-02-24

    A process is presented for recovering uranium from its ores. The crushed ore is mixed with 5 to 10% of sulfuric acid and added water to about 5 to 30% of the weight of the ore. This pugged material is cured for 2 to 3 hours at 100 to 110 deg C and then cooled. The cooled mass is nitrate-conditioned by mixing with a solution equivalent to 35 pounds of ammunium nitrate and 300 pounds of water per ton of ore. The resulting pulp containing 70% or more solids is treated by upflow percolation with a 5% solution of tributyl phosphate in kerosene at a rate equivalent to a residence time of about one hour to extract the solubilized uranium. The uranium is recovered from the pregnant organic liquid by counter-current washing with water. The organic extractant may be recycled. The uranium is removed from the water solution by treating with ammonia to precipitate ammonium diuranate. The filtrate from the last step may be recycled for the nitrate-conditioning treatment.

  16. Cationic flotation of some lithium ores

    International Nuclear Information System (INIS)

    Valadao, G.E.S.; Peres, A.E.C.; Silva, H.C. da

    1984-01-01

    The cationic flotation of some lithium ores (spodumene, amblygonite, petalite, lepidolite) is studied by the measure of zeta potential and micro-flotation tests in Hallimond tube. The effect of some modifier agents (corn starch, meta sodium silicate) on the lithium flotation is studied. (M.A.C.) [pt

  17. Flotation of uraniferous phosphorus ore from Itataia

    International Nuclear Information System (INIS)

    Aquino, J.A. de

    1984-01-01

    Flotation conditions, in laboratory and pilot scale, were established in a sample of Itataia uraniferous phosphorus ore which was basically constitute of apatite and calcite. The system of reagents-tall oil, collamil and sodium silicate-was studied in rougher, scavenger and cleaner stage. (M.A.C.) [pt

  18. Ferrite grade iron oxides from ore rejects

    Indian Academy of Sciences (India)

    Iron oxyhydroxides and hydroxides were synthesized from chemically beneficiated high SiO2/Al2O3 low-grade iron ore (57.49% Fe2O3) rejects and heated to get iron oxides of 96–99.73% purity. The infrared band positions, isothermal weight loss and thermogravimetric and chemical analysis established the chemical ...

  19. Chemical treatment of uranium ores in France

    International Nuclear Information System (INIS)

    Mouret, P.; Sartorius, R.

    1958-01-01

    The various processes of chemical treatment of uranium ores, from the oldest to the more recent, are exposed, considering the following conditions: economics, geography, techniques and safety. The interest of obtaining a final concentrate as uranyl nitrate is discussed. (author) [fr

  20. Production of thorium nitrate from uranothorianite ores

    International Nuclear Information System (INIS)

    Brodsky, M.; Sartorius, R.; Sousseuer, Y.

    1959-01-01

    The separation of thorium and uranium from uranothorianite ores, either by precipitation or solvent-extraction methods, are discussed, and an industrial process for the manufacture of thorium nitrate is described. Reprint of a paper published in 'Progress in Nuclear Energy' Series III, Vol. 2 - Process Chemistry, 1959, p. 68-76 [fr

  1. Price, technology, and ore reserves, ch. 2

    International Nuclear Information System (INIS)

    McAllister, A.L.

    1976-01-01

    Factors determining ore reserves in view of future uses are investigated: existing mining technologies, new techniques, price-technology relationship, effects of the use of different energy sources, exploration techniques, and price change are discussed. The effect of price and technology on reserves of specific commodities is dealth with. A section is also devoted to uranium

  2. Molybdenum extraction from copper-molybdenum ores

    International Nuclear Information System (INIS)

    Nevaeva, L.M.

    1982-01-01

    Molybdenum extraction from copper-molybdenum ores as practised in different countries is reviewed. In world practice the production process including depression of copper and iron sulfides and flotation of molybdenite is widely spread. At two USA factories the process of a selective flotation with molybdenite depression by dextrin is used

  3. Understanding Lateritic Ore Agglomeration Behaviour as a ...

    African Journals Online (AJOL)

    Processing such ores through cost-competitive heap (4-10 m high) leaching as an alternative, requires successful agglomeration of the feed into robust and porous granules. To date, produc-ing of granules with desirable attributes poses a major geotechnical challenge to industry. In the present work, we investigate ...

  4. Obtainment of tantalum oxide from national ores

    International Nuclear Information System (INIS)

    Pinatti, D.G.; Ribeiro, S.; Martins, A.H.

    1988-01-01

    The experimental results of tantalum oxides (Ta 2 O 5 ) obtainment from Brazilian ores of tantalite and columbite are described. This study is a part of the technologic and scientific research design of refractory metals (Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W) and correlate ceramics. (C.G.C.) [pt

  5. Economic outlook for radiometric selection of ores

    International Nuclear Information System (INIS)

    Formery, P.; Ziegler, V.

    1958-01-01

    The value of an ore can be increased by cutting off it's poor fractions. This selection may be realized at two stages: - part of the ore in situ is unable to cover it's extraction and treatment costs, this defines the 'underground cut-off grade'; - another portion of already extracted ore is unable to cover it's transport and treatment costs; this defines the 'surface cut off grade'. These selections are easily feasible owing to the property of uranium ores of emitting gamma radiations. A diagram makes possible a fast forecast on the effect of this selection upon the weight and metal yields. An attempt is made as well in order to provide the expected effect of the composition of underground cut off and surface cut off. This cut off however, being realized through an appreciation of the radiations, involves an alteration of the weight and metal yields which calls for a correction. A survey of the economic interest of the cut-off is done and an example of valorisation in a given deposit of a section at the limit of operability is proposed. (author) [fr

  6. A procedure for acid leaching of ores of the sandstone type, particularly of uranium ores

    International Nuclear Information System (INIS)

    Fiala, P.; Baloun, S.; Hinterholzinger, O.

    1990-01-01

    Ore mixed with the enriched fraction of the leached ore is leached with sulfuric acid at 5 to 220 degC. Bulky particles are sorted out from the mixture and reduced in size, and particles with a higher proportion of the useful component are separated from them. The latter particles constitute the enriched fraction of the leached ore, which is partially or completely returned to the mixture with the entering ore. The sorting should preferably be performed in an aqueous system. The assets of this procedure include a better homogenization of the mixture with the acid, a better stability of the reaction mixture which brings about reduced adhesion and solidification, and the possibility of extending the reaction time and increasing the temperature. The reduction in size makes for a better access of the leaching agent to the useful minerals, and the returning of the leachate to the reaction system spares sulfuric acid. (M.D.)

  7. A procedure for oxidation during the acid leaching of non-ferrous ores, particularly uranium ores

    International Nuclear Information System (INIS)

    Zubcek, L.; Baloun, S.; Martinek, K.; Vebr, Z.; Krepelka, J.; Lasica, S.

    1989-01-01

    It is suggested that dust from the production of ferroalloys of manganese, particularly ferrosilicomanganese and ferromanganese, can be conveniently used for oxidation during the acid leaching of non-ferrous ores, particularly uranium ores. This dust contains 30 to 40% oxides of manganese, about one-half of this is MnO 2 . Iron in the dust is present in the trivalent form, and the dust is pefectly dry. The conventional grinding of oxidants for the ore processing is eliminated, the dust being available in particle size below 0.2 mm. The dust is added in amounts of 5 to 100 kg per ton of the ore, and the suspension is typically heated at 115 degC for 3.5 hr. (P.A.)

  8. Is outdoor work associated with elevated rates of cerebrovascular disease mortality? : a cohort study based on iron-ore mining

    OpenAIRE

    Björ, Ove; Jonsson, Håkan; Damber, Lena; Burström, Lage; Nilsson, Tohr

    2016-01-01

    BACKGROUND: A cohort study that examined iron ore mining found negative associations between cumulative working time employed underground and several outcomes, including mortality of cerebrovascular diseases. In this cohort study, and using the same group of miners, we examined whether work in an outdoor environment could explain elevated cerebrovascular disease rates. METHODS: This study was based on a Swedish iron ore mining cohort consisting of 13,000 workers. Poisson regression models wer...

  9. Residues leaching from 'Factory of barren ores'

    International Nuclear Information System (INIS)

    Rakhmatov, N.; Khakimov, N.; Nazarov, Kh.M.; Barotov, A.M.

    2012-01-01

    The objective of the present work is safe management of residues from Factory of Barren Ores, their reprocessing, expenditures reduction for remediation of Istiklol city former uranium tailings. For this purpose, some experiences were adopted - Factory of Barren Ores tailing use for filling up the open pit where water with uranium content 3-5 mg/l is located. Factory of Barren Ores waste are passed through heap leaching and have some amount of uranium salts dissolved in water. Thus, we propose to dissolve uranium from Factory of Barren Ores wastes with uranium bearing water flowing out from gallery and filling up the open-pit by radioactive wastes. In so doing, uranium content flowing out from gallery will increase twice, and further, passing them through apricot's shell, as a sorbent, we will clean the water against radionuclides. Residue samples with uranium content 0,015% from Factory of Barren Ores and uranium bearing waters from gallery 1 with uranium content 0,0025 g/l were used for laboratory tests. After which, a slurry was prepared by means of residue mixing with water in ratio of solid and liquid phases (S:L) - 1:2 and 9,7 ml of sulfuric acid (Ρ=1,82) was added which corresponds consumption by H 2 SO 4 176,54 kg/t. For the first test, leaching was carried out during 4 hours at ph=1,6 at room temperature. For the second test, leaching was carried out at 60 d eg C a nd ph=1,6 during 4 hours. Slurry heating and mixing was carried out by means of magnetic mixer. The basic residue leaching indicators are provided in this article.

  10. Hydrogen Plasma Processing of Iron Ore

    Science.gov (United States)

    Sabat, Kali Charan; Murphy, Anthony B.

    2017-06-01

    Iron is currently produced by carbothermic reduction of oxide ores. This is a multiple-stage process that requires large-scale equipment and high capital investment, and produces large amounts of CO2. An alternative to carbothermic reduction is reduction using a hydrogen plasma, which comprises vibrationally excited molecular, atomic, and ionic states of hydrogen, all of which can reduce iron oxides, even at low temperatures. Besides the thermodynamic and kinetic advantages of a hydrogen plasma, the byproduct of the reaction is water, which does not pose any environmental problems. A review of the theory and practice of iron ore reduction using a hydrogen plasma is presented. The thermodynamic and kinetic aspects are considered, with molecular, atomic and ionic hydrogen considered separately. The importance of vibrationally excited hydrogen molecules in overcoming the activation energy barriers, and in transferring energy to the iron oxide, is emphasized. Both thermal and nonthermal plasmas are considered. The thermophysical properties of hydrogen and argon-hydrogen plasmas are discussed, and their influence on the constriction and flow in the of arc plasmas is considered. The published R&D on hydrogen plasma reduction of iron oxide is reviewed, with both the reduction of molten iron ore and in-flight reduction of iron ore particles being considered. Finally, the technical and economic feasibility of the process are discussed. It is shown that hydrogen plasma processing requires less energy than carbothermic reduction, mainly because pelletization, sintering, and cokemaking are not required. Moreover, the formation of the greenhouse gas CO2 as a byproduct is avoided. In-flight reduction has the potential for a throughput at least equivalent to the blast furnace process. It is concluded that hydrogen plasma reduction of iron ore is a potentially attractive alternative to standard methods.

  11. Geochemical prospecting techniques for ore deposits in periglacial regions

    International Nuclear Information System (INIS)

    Pitul'ko, V.M.

    1977-01-01

    Necessity and prospects of the implementation of geochemical methods of search in periglacial regions are discussed. The behaviour of chemical elements under the conditions of oxide and sulphate cryogenic topographies whose development has common regularities is analyzed. According to the specificity of migration the observed elements have been divided into four groups: active, mobile, low-mobile and inert migrants. Uranium which is present in ores in the form of pitchblende in oxide zones of the oxidation is actively redistributed. In zones of the oxidation of rare metal metasomatites connected with alkalic ultrabasic rocks only that part of U is mobile which being released from pyrochlore forms the regenerated uranium black and the partial enrichment of the iron gossan. Th like other elements of the 4-th group in all oxidation zones is observed to accumulate in minerals - concentrators: thorite, pyrochlore and so on. A diagram is plotted which characterizes the migration of elements whithin aureole landscapes as well as in automonous and dependent topographies of ore-free areas. The complex nature of secondary aureoles displays the most complete anomalous spectrum of elements - indicators of mineralization. The table of the most typical elements - indicators of the secondary scattering of some endogenic deposits of the cryolitic zone is given

  12. Uranium reduction by carbon oxide during ore formation

    International Nuclear Information System (INIS)

    Matyash, I.V.; Gavrusevich, I.B.; Pasal'skaya, L.F.; Shcherba, D.I.

    1981-01-01

    Using the method of gas chromatography the gas content in Pre-Cambrian granitoils of various types and in natrometasomatites associted with them is studied. It is established that granites associated with ore-bearing albitites have sharply elevated amounts of CO as compared with granites, which do not include mineralization. Simultaneously in ore samples the absence or sharply low amounts of CO as compared with ore-free samples is observed, that is reverse dependence of CO and ore components. Carbon oxide is the reducing agent of uranium mineralization and alongside with other reducing agents can be a geochemical barrier in the process of ore formation [ru

  13. A literature survey of the matallurgical aspects of minerals in Witwatersrand gold ores

    International Nuclear Information System (INIS)

    De Waal, S.A.

    1982-01-01

    This survey reviews the information in the literature on the auriferous rock formations in the Witwatersrand-Orange Free State gold-mining area, the gold-bearing horizons, and the mineralogy and petrography of the different ore types. The metallurgical aspects of the gold, silver, uranium, platinum-group elements, cobalt, nickel, copper, and chromite in these ores are examined and, on the strength of this information, a list is given of those problems in metallurgical extraction that are of a mineralogical nature. Finally, a number of research projects, aimed to support current research at the Council for Mineral Technology, are suggested

  14. Occupational Contact Dermatitis in North American Production Workers Referred for Patch Testing: Retrospective Analysis of Cross-Sectional Data From the North American Contact Dermatitis Group 1998 to 2014.

    Science.gov (United States)

    Warshaw, Erin M; Hagen, Solveig L; DeKoven, Joel G; Zug, Kathryn A; Sasseville, Denis; Belsito, Donald V; Zirwas, Matthew J; Fowler, Joseph F; Taylor, James S; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Maibach, Howard I; Mathias, C G Toby

    Little is known about the epidemiology of contact dermatitis in production workers (PWs). The aims of this study were to estimate the prevalence of contact dermatitis and characterize clinically relevant and occupationally related allergens among North American PWs undergoing patch testing. This was a retrospective cross-sectional analysis of North American Contact Dermatitis Group data from 1998 to 2014. Of 39,332 patch-tested patients, 2732 (7.0%) were PWs. Among PWs, most were men (62.4%) and white (83.9%). A history of childhood eczema was uncommon (11.3%). Prevalent occupations included machine operators (27.3%); fabricators, assemblers, and hand-working occupations (16.8%); and precision metalworking occupations (16.1%). The most frequent sites of dermatitis were the hands (53.8%) and arms (29.4%), which were significantly more commonly affected compared with non-PWs (P contact dermatitis, and irritant contact dermatitis were also significantly more common in PWs (49.9% vs 10.6%, 58.9% vs 53.7%, and 32.7% vs 25.7%, respectively; all Ps contact dermatitis. Involvement of exposed body areas was common. Frequently identified allergens included adhesives/glues, rubber accelerators, metals, and preservatives.

  15. High-rate behaviour of iron ore pellet

    Science.gov (United States)

    Gustafsson, Gustaf; Häggblad, Hans-Åke; Jonsén, Pär; Nishida, Masahiro

    2015-09-01

    Iron ore pellets are sintered, centimetre-sized spheres of ore with high iron content. Together with carbonized coal, iron ore pellets are used in the production of steel. In the transportation from the pelletizing plants to the customers, the iron ore pellets are exposed to different loading situations, resulting in degradation of strength and in some cases fragmentation. For future reliable numerical simulations of the handling and transportation of iron ore pellets, knowledge about their mechanical properties is needed. This paper describes the experimental work to investigate the dynamic mechanical properties of blast furnace iron ore pellets. To study the dynamic fracture of iron ore pellets a number of split Hopkinson pressure bar tests are carried out and analysed.

  16. Mineralogical and paragenetical problems of the Mecsek uranium ore

    International Nuclear Information System (INIS)

    Vincze, J.; Fazekas, V.

    1979-01-01

    The latest results of the ore-mineralogical examination of the uranium ore of a deposit included in Permian sandstones in the Mecsek Mountains, southern Hungary, are presented. The phases of the minerals belonging to the uranium oxide series and their types of development, the post-coffinite nasturan pseudomorphs and the relationship between nasturan and coffinite are dealt with. Of the sulphide ore minerals associated with uranium ore mineralization the type determinant mineral is pyrite, i.e. the mineral forming their bulk and partly represented by characteristically finely aggregated ''bacteriopyrite'' and/or spherical pyrite and ''framboidal pyrite. The textural pattern of the ore mineralization is of typically matrix type. The matrix of sandstone is constituted by carbonate minerals, ''hydromicas'' and ore minerals. The matrix and, consequently, the ore minerals will corrode and consume the allothigenic detrital rockforming minerals, the feldspar, quartz-porphyry and quartz. (A.L.)

  17. Occupational Contact Dermatitis in Mechanics and Repairers Referred for Patch Testing: Retrospective Analysis From the North American Contact Dermatitis Group 1998-2014.

    Science.gov (United States)

    Warshaw, Erin M; Hagen, Solveig L; Sasseville, Denis; Maibach, Howard I; DeKoven, Joel G; Belsito, Donald V; Fowler, Joseph F; Zug, Kathryn A; Taylor, James S; Mathias, C G Toby; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Zirwas, Matthew J; Storrs, Frances J

    Contact dermatoses are common in mechanic and repair occupations. This study aimed to (1) estimate the prevalence of occupationally related contact dermatitis among mechanics/repairers patch tested from 1998 to 2014 by the North American Contact Dermatitis Group, (2) characterize responsible allergens and irritants, and their sources, and (3) compare results among 3 occupational subgroups (mechanics, electrical/electronic, and other). A cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group between 1998 and 2014. Of 38,784 patients patch tested, 691 (1.8%) were mechanics/repairers. Male sex (93.5%) and hand involvement (59.5%) were common overall. Occupationally related skin disease was more prevalent among vehicle and mobile equipment mechanics/repairers (52.7%) and other mechanics/repairers (41.4%) than electrical/electronic equipment mechanics/repairers (21.3%). Overall, carba mix, thiuram mix, and methylchloroisothiazolone/methylisothiazolone were the most common occupation-related clinically relevant allergens. Gloves, automotive vehicles, solvents, oils, lubricants, and fuels were the most common sources of responsible allergens. Common occupationally related allergens included rubber accelerators and the preservative methylchloroisothiazolone/methylisothiazolone.

  18. Analytical fingerprint for tantalum ores from African deposits

    Science.gov (United States)

    Melcher, F.; Graupner, T.; Sitnikova, M.; Oberthür, T.; Henjes-Kunst, F.; Gäbler, E.; Rantitsch, G.

    2009-04-01

    Illegal mining of gold, diamonds, copper, cobalt and, in the last decade, "coltan" has fuelled ongoing armed conflicts and civil war in a number of African countries. Following the United Nations initiative to fingerprint the origin of conflict materials and to develop a traceability system, our working group is investigating "coltan" (i.e. columbite-tantalite) mineralization especially in Africa, also within the wider framework of establishing certified trading chains (CTC). Special attention is directed towards samples from the main Ta-Nb-Sn provinces in Africa: DR Congo, Rwanda, Mozambique, Ethiopia, Egypt and Namibia. The following factors are taken into consideration in a methodological approach capable of distinguishing the origin of tantalum ores and concentrates with the utmost probability: (1) Quality and composition of coltan concentrates vary considerably. (2) Mineralogical and chemical compositions of Ta-Nb ores are extremely complex due to the wide range of the columbite-tantalite solid solution series and its ability to incorporate many additional elements. (3) Coltan concentrates may contain a number of other tantalum-bearing minerals besides columbite-tantalite. In our approach, coltan concentrates are analyzed in a step-by-step mode. State-of-the-art analytical tools employed are automated scanning electron microscopy (Mineral Liberation Analysis; MLA), electron microprobe analysis (major and trace elements), laser ablation-ICP-MS (trace elements, isotopes), and TIMS (U-Pb dating). Mineral assemblages in the ore concentrates, major and trace element concentration patterns, and zoning characteristics in the different pegmatites from Africa distinctly differ from each other. Chondrite-normalized REE distribution patterns vary significantly between columbite, tantalite, and microlite, and also relative to major element compositions of columbites. Some locations are characterized by low REE concentrations, others are highly enriched. Samples with

  19. More light on the U clan. [Uranium behaviour in complex ores

    Energy Technology Data Exchange (ETDEWEB)

    De Waal, S.A. (Potchefstroom Univ. for C.H.E. (South Africa). Dept. of Geology)

    1983-07-01

    A thorough knowledge of the geochemistry of uranium is necessary for the exploration and beneficiation of this mineral. At present we lack knowledge of the behaviour of uranium minerals in complex ores. This article deals with the geochemistry of uranium, its group identity, uranium minerals and the extraction mineralogy.

  20. High temperature attack of ores by a liquor containing essentially a soluble bicarbonate

    International Nuclear Information System (INIS)

    Maurel, Pierre; Nicolas, Francois; Bosca, Bernard.

    1978-01-01

    New process for high temperature oxidizing digestion of ores containing at least one metal in the uranium, vanadium and molybdenum group, by an aqueous liquor containing sodium bicarbonate and sodium carbonate in the presence of free oxygen insufflated into the reaction medium [fr

  1. Genetic data suggests that the Jinggouzi people are associated with the Donghu, an ancient nomadic group of North China.

    Science.gov (United States)

    Wang, Haijing; Chen, Lu; Ge, Binwen; Zhang, Ye; Zhu, Hong; Zhou, Hui

    2012-08-01

    Nomadic populations have played a significant role in the history of not only China but also in many nations worldwide. Because they had no written language, an important aspect in the study of these people is the discovery of their tombs. It has been generally accepted that Xiongnu was the first empire created by a nomadic tribe in the 3rd century BC. However, little population genetic information is available concerning the Donghu, another flourishing nomadic tribe at the same period because of the restriction of materials until the Jinggouzi site was excavated. In order to test the genetic characteristics of ancient people in this site and to explore the relationship between Jinggouzis and Donghus, two uniparentally inherited markers were analyzed from 42 human remains in this site, which was located in northern China, dated approximately 2500 years ago. With ancient DNA technology, four mtDNA haplogroups (D, G, C, and M10) and one Y chromosome haplogroup (C) were identified using mitochondrial DNA and Y-chromosome single nucleotide polymorphisms. Those haplogroups are common in North Asia and East Asia. The Jinggouzi people were genetically closest to the Xianbeis in ancient populations and to the Oroqens among extant populations, who were all pastoralists. This might indicate that ancient Jinggouzi people were nomads. Meanwhile, according to the genetic data and the evidences in archaeology, we inferred that Jinggouzi people were associated with Donghu. It is of much value to trace the history of the Donghu tribe and this might show some insight into the ancient nomadic society.

  2. Influence of matrix metalloproteinase gene polymorphisms in healthy North Indians compared to variations in other ethnic groups worldwide.

    Science.gov (United States)

    Srivastava, Priyanka; Kapoor, Rakesh; Mittal, Rama Devi

    2009-01-01

    Matrix metalloproteinases have a range of biological functions, including the liberation of cytokines and membrane-bound receptors, with roles in promotion of tumor invasion and angiogenesis. Several polymorphisms in MMPs have been implicated in the development of cancer as well as other diseases. Since their frequency distributions in the general North Indian population is not known the present study was conducted with the focus on MMP-1(-519) Aandgt; G, MMP-1(-1607) 1Gandgt; 2G, and MMP-7(-181) Aandgt; G gene polymorphisms. PCR-based analysis was conducted for 200 normal healthy individuals of similar ethnicity. Allelic frequencies in wild type of MMP-1(-519) Aandgt; G were 71.2% A; MMP-1(-1607) 1Gandgt; 2G 48.2% 1G; MMP-7(-181) Aandgt; G 60.7% A. The variant allele frequencies were 29% A in MMP-1(-519) Aandgt; G; 52% 2G in MMP-1(-1607) 1Gandgt; 2G; and 39.3% G in MMP-7(-181) Aandgt; G respectively. We further compared frequency distribution for these genes with various published studies in different ethnicity globally. Our results suggest that frequency in these MMP genes exhibit distinctive patterns in India that could perhaps be attributed to ethnic variation. This study is important as it can form a baseline for screening individuals who are at high risk when exposed to environmental carcinogens. More emphasis is needed on evaluating polymorphisms, alone or in combination, as modifiers of risk from relevant environmental/lifestyle exposures.

  3. Papers of the Ziff Energy Group's 30. North American gas strategies conference : setting the stage : energy policy to market

    International Nuclear Information System (INIS)

    2005-01-01

    Policies and economic drivers concerning the natural gas industry were the focus of this conference, which was divided into 3 sessions. The first session examined various policy issues and perspectives from government officials in North America. High energy prices and regulations concerning land access were reviewed, as well as supply costs and infrastructure needs. Outlooks for the natural gas industry in Alberta and British Columbia were presented. Issues concerning coalbed methane (CBM) and accessing off-shore natural gas were discussed. Activities in the Yukon were outlined. Land claim settlements were reviewed, and the development of a liquefied natural gas (LNG) infrastructure in Mexico was examined. Issues concerning the role of the natural gas industry in oil sands developments were addressed, as well as pipelines challenges and gas price impacts. Session 2 examined pipeline developments and infrastructure needs. Issues concerning stress corrosion cracking and the increase in Canadian pipelines were reviewed along with rates of return and market needs. Challenges facing natural gas infrastructure in the northeast were outlined and the impacts of LNG and northern supply were evaluated. Session 3 examined the impact of high gas prices. Macroeconomic impacts to the United States economy were discussed, as well as the impact of rising natural gas prices on the industrial sector. Issues concerning contract terms, credit terms, traded volumes and hedging were examined. Advances in temperature forecasting were reviewed. Short term price impacts and fundamental supply and demand issues were reviewed in relation to marketplace needs. Eleven presentations were given at this conference, of which 5 have been catalogued separately for inclusion in this database. tabs., figs

  4. Patch test reactions associated with sunscreen products and the importance of testing to an expanded series: retrospective analysis of North American Contact Dermatitis Group data, 2001 to 2010.

    Science.gov (United States)

    Warshaw, Erin M; Wang, Michael Z; Maibach, Howard I; Belsito, Donald V; Zug, Kathryn A; Taylor, James S; Mathias, C G Toby; Sasseville, Denis; Zirwas, Matthew J; Fowler, Joseph F; DeKoven, Joel G; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Storrs, Frances J

    2013-01-01

    Both active and inactive ingredients in sunscreen may cause contact dermatitis. This study aimed to describe allergens associated with a sunscreen source. A cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group between 2001 and 2010 was performed. Of 23,908 patients patch tested, 219 (0.9%) had sunscreen coded as an allergen source. Patients who were male, with occupational dermatitis, or older (older than 40 years) had significantly lower rates of allergic reactions to sunscreens; the most commonly affected areas were the face and exposed sites (P Contact Dermatitis Group screening series of 65 to 70 allergens. A supplemental antigen series is important in detecting allergy to sunscreens.

  5. Prospects for increasing uranium resources in the Khiagda ore field (Russian Federation)

    International Nuclear Information System (INIS)

    Novgorodtcev, A.; Martynenko, V.; Gladyshev, A.

    2014-01-01

    The Khiagda ore field uranium deposits are located in the Republic of Buryatia, on the Amalat Plateau formed by the Neogene basalts. The position of the ore field is defined by a large tectonic structure having a north-eastern strike the Baisykhan Uplift. The slopes of the Baisykhan dividing uplift are incised by short (4 to 16 km) lateral tributaries of the Amalat and Atalanga paleorivers. The paleovalley network is filled with terrigenous-volcanogenic units of the Miocene Dzhilinda Formation (N1dz) buried under a thick cover of plateau basalts. The upheaval of the Baisykhan Uplift in the Neogene caused the penetration of the hydrodynamic flow of oxygenous uranium-bearing water into the sedimentary rock mass and formation of the subsoil/tabular oxidation zone (STOZ) on the boundary of which there formed uranium mineralisation.

  6. Bioleaching of a manganese and silver Ore

    International Nuclear Information System (INIS)

    Porro, S.; Tedesco, P.H.; La Plata

    1990-01-01

    The bioleaching with a strain of Thiobacillus thiooxidans of the ore of Farallon Negro (Catamarca, Argentina) was studied in order to estimate its application to the solution and recovery of the manganese, and to improve the silver extraction. The State company which works the mine has not yet found an economical process to extract the manganese and has only reached a 30% efficiency in the recovery of silver by cianuration. The effects of pulp density variations and the addition of different quantities of FeS were analysed looking for the best working conditions. 74 μm (mesh Tyler 200) of ore particles were used because that is the size used in this plant for the cianuration process. (Author)

  7. Fission track method for uranium ore exploration

    International Nuclear Information System (INIS)

    Guo Shilun; Deng Xinlu; Sun Shengfen; Meng Wu; Zhang Pengfa; Hao Xiuhong

    1986-01-01

    The uranium concentrations in natural water collected in the fields of uranium ore exploration with fission track method have been determined. It shows that the results of fission track method are consistent with that of fluoro-colorimetry and laser fluorometry for the same samples of water with uranium concentration in the region of 10 -4 to 10 -8 g/l. For water samples with lower uranium concentration (≤10 -8 g/l), the fission track method can still give accurate or referential results, but the other two methods failed. The reproducibility of fission track method was checked and discussed by using samples collected in the same fields of uranium ore exploration. The effects of the concentration of the impurities in natural water on determination of uranium concentration were analysed and discussed as well

  8. Dose calculations for intakes of ore dust

    International Nuclear Information System (INIS)

    O'Brien, R.S.

    1998-08-01

    This report describes a methodology for calculating the committed effective dose for mixtures of radionuclides, such as those which occur in natural radioactive ores and dusts. The formulae are derived from first principles, with the use of reasonable assumptions concerning the nature and behaviour of the radionuclide mixtures. The calculations are complicated because these 'ores' contain a range of particle sizes, have different degrees of solubility in blood and other body fluids, and also have different biokinetic clearance characteristics from the organs and tissues in the body. The naturally occurring radionuclides also tend to occur in series, i.e. one is produced by the radioactive decay of another 'parent' radionuclide. The formulae derived here can be used, in conjunction with a model such as LUDEP, for calculating total dose resulting from inhalation and/or ingestion of a mixture of radionuclides, and also for deriving annual limits on intake and derived air concentrations for these mixtures

  9. Introduction - Acid decomposition of borosilicate ores

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Kurbonov, A.S.; Mamatov, E.D.

    2015-01-01

    The complex processing of mineral raw materials is an effective way for the extraction of valuable components. One of these raw materials are borosilicate ores from which the boric acid, aluminium and iron salts and building materials can be obtained. In the Institute of Chemistry of the Academy of Sciences of the Republic of Tajikistan the flowsheets of the processing of borosilicate raw materials by acid and chloric methods were elaborated. The acid methods of decomposition of borosilicate ores of Ak-Arkhar Deposit were considered in present monograph. The carried out researches on elaboration of physicochemical aspects and technological acid methods allowed to define the optimal ways of extraction of valuable products from borosilicate raw materials of Tajikistan.

  10. RL-1: a certified uranium reference ore

    International Nuclear Information System (INIS)

    Steger, H.F.; Bowman, W.S.

    1985-06-01

    A 145-kg sample of a uranium ore from Rabbit Lake, Saskatchewan, has been prepared as a compositional reference material. RL-1 was ground to minus 74 μm and mixed in one lot. Approximately one half of this ore was bottled in 100-g units, the remainder being stored in bulk. The homogeneity of RL-1 with respect to uranium and nickel was confirmed by neutron activation and X-ray fluorescence analytical techniques. In a 'free choice' analytical program, 13 laboratories contributed results for one or more of uranium, nickel and arsenic in one bottle of RL-1. Based on a statistical analysis of the data, the following recommended values were assigned: U, 0.201%; Ni, 185 μg/g; and As, 19.6 μg/g

  11. Modeling drying of iron ore pellets

    OpenAIRE

    Ljung, Anna-Lena

    2010-01-01

    Iron ore pellets are a highly refined product supplied to the steel making industry for use in blast furnaces or direct reduction processes. The use of pellets offers many advantages such as customer adopted products, transportability and mechanical strength yet the production is time and energy consuming. Being such, there is a natural driving force to enhance the pelletization in order to optimize production and improve quality. The aim with this thesis is to develop numerical models with w...

  12. Physical fitness examination in a selected group of the North-Moravian industrial population. I: Results in coke plant workers

    Energy Technology Data Exchange (ETDEWEB)

    Jirac, Z

    1974-01-01

    Basic spirographic and spiroergometric examinations, according to Hollman, were performed on 269 men, aged 20-60 years, who had been working at coke-oven batteries for 1, 16 and more years. There were no significant differences in the spirographic and spiroergometric indicators of cardiopulmonary efficiency in relation to the length of exposure within the age groups. Maximum oxygen uptake in younger men (20-29 years) was identical, in older age groups it was below average according to Hollmann. This phenomenon can be explained by a combined effect of a low physical load and the heat load on the cardiovascular system. Values were compared with those of Shepard. The working and sanitary conditions and investigation methods are described in detail.

  13. The role of climatic cycles and trans-Saharan migration corridors in species diversification: Biogeography of Psammophis schokari group in North Africa.

    Science.gov (United States)

    Gonçalves, Duarte Vasconcelos; Martínez-Freiría, Fernando; Crochet, Pierre-André; Geniez, Philippe; Carranza, Salvador; Brito, José Carlos

    2018-01-01

    Highlands, hydrographic systems and coastal areas have been hypothesised to form corridors across the hyperarid Sahara desert in North Africa, allowing dispersal and gene flow for non-xeric species. Here we aim to provide a genetic test for the trans-Saharan corridor model, and predict the location and stability of ecological-corridors, by combining phylogeography and palaeoclimatic modelling. The model was the Psammophis schokari (Schokari sand racer) group, fast-moving and widely distributed generalist colubrids occurring mostly in arid and semiarid scrublands. We combined dated phylogenies of mitochondrial and nuclear markers with palaeoclimatic modelling. For the phylogeographic analysis, we used 75 samples of P. schokari and P. aegyptius, and Bayesian and Maximum-Likelihood methods. For the ecological models, we used Maxent over the distribution of P. schokari and West African lineages. Models were projected to past conditions (mid Holocene, Last Glacial Maximum and Last Inter-Glacial) to infer climatic stable areas. Climatic stability was predicted to be mostly restricted to coastal areas and not spatially continuous. A putative temporary trans-Saharan corridor was identified in Eastern Sahara, with a more stable one along the Atlantic coast. Six parapatric lineages were identified within P. schokari, four occurring in North Africa. These likely diverged during the Pliocene. The Tamanraset River might have been a vicariant agent. African lineages may have experienced further subsequent diversification during the late Pleistocene. The main P. schokari refugia were probably located along the northern margins of the Sahara, allowing its North-to-South colonization. Trans-Saharan corridors seem to have played a role in P. schokari biogeography, allowing colonization of central Saharan mountains and Sahel. Some might have worked as refugia, and even the most stable corridors may have sections working as filters, depending on each climatic phase. We expect the use

  14. Hydrometallurgical Processing Technology of Titanomagnetite Ores

    Directory of Open Access Journals (Sweden)

    Victor Ivanovich Sachkov

    2017-12-01

    Full Text Available In this paper, we study the possibility of obtaining iron and titanium-vanadium concentrates with highest contents of iron and titanium, respectively, through hydrometallurgical processing of the titanomagnetite ores of the Chineisk deposit. We varied two key parameters to determine the efficiency of the process: (a concentration of leaching solution (ammonium fluoride; and (b acidity of solution. Ammonium fluoride concentration was varied from 0.08 mol/L to 4.2 mol/L with the other fixed parameters. It was shown that optimum ammonium fluoride concentration for leaching the ore is 0.42 mol/L; at these concentrations iron and titanium contents are about 62.8 wt % and 3.5 wt % in solid phase, respectively. The acidity of solution was changed by adding of hydrofluoric acid with varied concentration (from 0.86 mol/L to 4.07 mol/L to ammonium fluoride solution with fixed concentration of 0.42 mol/L. The best results (degree of titanium extraction = 63.7% were obtained when using a solution of hydrofluoric acid with concentration 4.07 mol/L. In this case, the addition of acid makes it possible to increase the Fe/Ti ratio by 3.4 times in comparison with the original ore. Thus, we conclude that acidity and the concentration of ammonium fluoride solution significantly influences the selectivity of the hydrometallurgical process.

  15. Potential health hazard of nuclear fuel waste and uranium ore

    International Nuclear Information System (INIS)

    Mehta, K.; Sherman, G.R.; King, S.G.

    1991-06-01

    The variation of the radioactivity of nuclear fuel waste (used fuel and fuel reprocessing waste) with time, and the potential health hazard (or inherent radiotoxicity) resulting from its ingestion are estimated for CANDU (Canada Deuterium Uranium) natural-uranium reactors. Four groups of radionuclides in the nuclear fuel waste are considered: actinides, fission products, activation products of zircaloy, and activation products of fuel impurities. Contributions from each of these groups to the radioactivity and to the potential health hazard are compared and discussed. The potential health hazard resulting from used fuel is then compared with that of uranium ore, mine tailings and refined uranium (fresh fuel) on the basis of equivalent amounts of uranium. The computer code HAZARD, specifically developed for these computations, is described

  16. Electron microscopy and microanalysis of uranium phases in primary ores, Eocene and Miocene of south Texas

    International Nuclear Information System (INIS)

    Liang, L.C.; Price, J.G.; Bobeck, P.

    1984-01-01

    Two contrasting types of roll-front uranium deposits occur in south Texas. In the barrier-bar sands of the Eocene Jackson Group, organic matter was essential to uranium reduction, whereas in the fluvial sands of the Miocene Oakville Formation, epigenetic pyrite was the reductant. In a sample of reduced Oakville ore, a uranium phase with grains ranging in diameter from < 1 to 20μm was recognized by SEM backscattered-electron imaging and wavelength-dispersive spectrometer (WDS) elemental-dot mapping. Quantitative microprobe analyses indicated that the phase is a uranium-calcium silicate-phosphate with molar Ca/P approximately equal to 1.0, U/P equal to 2.8 +/- 0.4 (n = 27), and U/Si approaching 1.0 in samples uncontaminated with quartz, feldspar, or clay minerals. Highest uranium content is 59%. Oakville ore is typically easy to leach by in-situ methods. Jackson ore contains 2 uranium phases. Sulfur-rich organic matter contains 4.1 +/- 1.6% uranium (n = 27). Although individual grains of a possible uranium mineral within the organic matter are too small to be resolved by electron imaging, a consistent molar U/Fe (0.5 +/- 0.1) suggests a uranium-iron oxide phase. Alternatively, uranium is adsorbed by or otherwise bound to the organic matter. The second phase is a uranium-calcium silicate-phosphate that differs from the Oakville ore. Molar Ca/P equals 0.8 +/- 0.2 (n = 13), and U/P equals 4.7 +/- 0.4. Small grain size (generally less than 1 μm) prevented analysis of samples uncontaminated with quartz and pyrite. The grain with highest uranium content (43%) has U/Si equal to 0.34. Jackson ore is less favorable for in-situ leaching than Oakville ore in part because the organic-associated uranium is difficult to extract

  17. Grade control and the determination of ore reserves at a low-grade uranium mine

    International Nuclear Information System (INIS)

    Reid, J.A.F.; Robertson, B.

    1982-01-01

    In 1966 an intensive exploration programme was conducted by Rio Tinto South Africa Ltd, involving airborne and ground radiometric surveys, percussion and diamond drilling, and pilot-plant tests. This investigation established the presence of a large deposit of low-grade uranium that could be mined on a large scale by open-pitting. Soon after production started in June 1974, it was realized that the original presentation of the ore reserves did not give a true reflection of the orebody. A comparison between the estimates and the ore mined from reserve blocks over the period 1975 to 1977 showed that the reserve grades were over-optimistic. In 1977 Rio Tinto Zinc Consultants were commissioned to re-evaluate the ore reserves from exploration diamond-drill data with the help of The Centre de Geostatistique at Fontainebleau, France. A new global reserve using disjunctive kriging techniques was developed, and is now the long-term reserve used for planning purposes at the Roessing Mine. For short-term planning, ore-reserve data are replaced by information from an intermediate drilling programme and blast-hole assays if these are available. A computerized short-term planning system has been established that reconciles the ore mined against the reserve blocks, as well as a system by which composited blast-hole assays are analysed for grade-control purposes. Owing to the complexity of the orebody, additional monitoring is achieved by the scanning of each truckload of ore with a group of scintillation crystal heads that evaluate the material mined

  18. Geology of eastern Smith Lake ore trend, Grants mineral belt

    International Nuclear Information System (INIS)

    Ristorcelli, S.J.

    1980-01-01

    The sandstones in the Brushy Basin Member of the Morrison Formation (Jurassic) are the ore-bearing horizons of the eastern Smith Lake area. The Brushy Basin Member in this district consists of three sandstones with interbedded mudstones. Only the lower two sandstones contain ore. The sandstones are fine to coarse grained, well rounded, and arkosic, representing continental stream sediments. The lower sandstone contains rollfront ore. The redox interface is laterally extensive and well defined, extending at least 7 mi (11 km) west of the Bluewater fault zone. The ore generally occurs at the redox boundary but occasionally will be up to 1500 ft (450 m) updip. Limonitic alteration, where present, is downdip from the hematitic zone and is 100-1,500 ft (30 to 450 m) wide. The middle sandstone contains both trend ore and roll-front ore. The trend ore occurs downdip from the redox front in unoxidized ground. The redox front in the middle sand is also laterally extensive but displays a wedge shape, rather than a C shape. The clay assemblages of the two types of ore are different: the trend ore occurs in sands with the pore spaces filled with kaolinite; the roll-front ore is associated with altered illite-montmorillonite as grain coatings. Hematitic alteration is asociated with the latter. A second stage of kaolinite coats the illite-montmorillonite. Two periods of mineralization are suggested, but no absolute dates are known. The trend ore is the oldest (Jurassic) and is similar to the ore found in unoxidized ground elsewhere in the Grants region. The rollfront ore could be Laramide or post-Laramide because of its association with local Laramide structures

  19. Isotopic measurements of carbon and oxygen in carbonates from Bambui Group in the center-north region of Bahia State

    International Nuclear Information System (INIS)

    Torquato, J.R.; Misi, A.

    1978-01-01

    Analyses of 85 carbonate samples of the Bambui Group from the Chapada de Irece, Bahia, exhibit four distinct 13 C and 18 O isotopic ratio groupings. Based on these results the following sedimentation model for the Bambui Group is proposed: 1. A continental environment originating the basal dolomitic limestones and argillacceous dolomites. Isotopic ratios from these rocks fall within ranges considered typical of continental sedimentation: delta 18 C between -2.9 and -6.4%o, and delta 18 O from -5.3 to -10.7%o (PDB). 2. An alternating continental and restricted marine environment resulting in the deposition of laminated dolomitic limestones with thin interbeds of muddy sediments. Delta 13 C ratios of +0.1 to -4.9%o and a mean value of -8.2+-0.3%o delta 18 O are compatible with such an environment. 3. A restricted marine environment dominated by sedimentation of the black, fetid limestones of the upper portion of the sequence. Isotopic ratios for 13 C are all over -1.8%o, up to about +7.5%o, and 18 O ratios vary from-4.9 to -10.0%o. A number of light-grey sileceous dolomites is interbered with the lowermost black limestones of this sequence. Isotopic data for these rocks show a narrow range for delta 18 C values (-0.5 to 1.0%o) and a broader variation for delta 18 O ratios (0.0 to -8.3%o). This latter may be interpreted as indicative of intense evaporation during deposition of the dolomitic facies [pt

  20. Advances and Opportunities in Ore Mineralogy

    Directory of Open Access Journals (Sweden)

    Nigel J. Cook

    2017-11-01

    Full Text Available The study of ore minerals is rapidly transforming due to an explosion of new micro- and nano-analytical technologies. These advanced microbeam techniques can expose the physical and chemical character of ore minerals at ever-better spatial resolution and analytical precision. The insights that can be obtained from ten of today’s most important, or emerging, techniques and methodologies are reviewed: laser-ablation inductively-coupled plasma mass spectrometry; focussed ion beam-scanning electron microscopy; high-angle annular dark field scanning transmission electron microscopy; electron back-scatter diffraction; synchrotron X-ray fluorescence mapping; automated mineral analysis (Quantitative Evaluation of Mineralogy via Scanning Electron Microscopy and Mineral Liberation Analysis; nanoscale secondary ion mass spectrometry; atom probe tomography; radioisotope geochronology using ore minerals; and, non-traditional stable isotopes. Many of these technical advances cut across conceptual boundaries between mineralogy and geochemistry and require an in-depth knowledge of the material that is being analysed. These technological advances are accompanied by changing approaches to ore mineralogy: the increased focus on trace element distributions; the challenges offered by nanoscale characterisation; and the recognition of the critical petrogenetic information in gangue minerals, and, thus the need to for a holistic approach to the characterization of mineral assemblages. Using original examples, with an emphasis on iron oxide-copper-gold deposits, we show how increased analytical capabilities, particularly imaging and chemical mapping at the nanoscale, offer the potential to resolve outstanding questions in ore mineralogy. Broad regional or deposit-scale genetic models can be validated or refuted by careful analysis at the smallest scales of observation. As the volume of information at different scales of observation expands, the level of complexity

  1. Application of the Dose Limitation System to the Mining and Milling of Radioactive Ores

    International Nuclear Information System (INIS)

    1987-01-01

    This publication is one of the Safety Guides to the Code of Practice on Radiation Protection of Workers in the Mining and Milling of Radioactive Ores, 1983 Edition, which was published as a joint IAEA/ILO/WHO publication (IAEA Safety Series No.26). This Safety Guide is intended to demonstrate as well as facilitate the application of the principles of optimization in the control of risk among the workers engaged in the mining and milling of radioactive ores and to give some guidance on suitable technology. The International Atomic Energy Agency, jointly with the World Health Organization, the International Labour Organisation and the OECD Nuclear Energy Agency, published the Basic Safety Standards for Radiation Protection, 1982 Edition (IAEA Safety Series No. 9). The Basic Safety Standards outline the principles of radiation protection and also the basic requirements to be followed in the implementation of radiation protection control. These principles are further developed in the case of mining and milling of radioactive ores in the joint IAEA/ILO/WHO Code of Practice on Radiation Protection of Workers in the Mining and Milling of Radioactive Ores (IAEA Safety Series No. 26). This Safety Guide on the Application of the Dose Limitation System to the Mining and Milling of Radioactive Ores was prepared by an Advisory Group which met for the first time in Portoroz, Yugoslavia, from 22 to 26 August 1983, and then again from 6 to 10 August 1984, in Vienna. Following the second Advisory Group meeting the draft was further reviewed by A. Dory from Canada who also was a participant of the two Advisory Group meetings held earlier. After the consultant's review the draft was circulated among the members of the Advisory Group for a further check. The final version of the draft was prepared by the Secretariat with the help of a consultant

  2. Geology and ore deposits of the Klondike Ridge area, Colorado

    Science.gov (United States)

    Vogel, John David

    1960-01-01

    part of the basal sandstone unit of the Salt Wash member of the Morrison formation. Most deposits are in a narrow, elongate mineral belt' that cuts obliquely across Klondike Ridge. The remaining deposits probably form a second 'mineral belt' lying about ? mile to the north. Manganese and copper deposits show both stratigraphic and structural controls of mineralization. Most manganese deposits are in red beds near Tertiary faults; most copper deposits, on the other hand, are in brown sandstone, limestone, or gray-green shale and, like manganese, are in or near Tertiary faults. The manganese and copper deposits are hydrothermal in origin and were formed in the roots of an ancient hot springs system, now deeply eroded. The ore-bearing solutions probably consisted of dilute, carbonate-sulfate ground water heated by the near-surface intrusion of small bodies of igneous rock. These solutions obtained their metals by leaching the wallrock; little, if any, material was added by the intrusives. The deposits were formed near the surface under conditions of hydrostatic pressure, and temperatures and pressures in the ore-bearing solutions were probably low. The early solutions were weakly alkaline and reducing in character. A convection cell was established as mineralization progressed, and surface water mingled at depth with the solutions. As a result of mixing and oxidation, the pH of the solution decreased in later stages of mineralization and the Eh rose.

  3. Effects of barium chloride treatment of uranium mill tailings and ore on radon emanation and 226Ra levels. Progress report

    International Nuclear Information System (INIS)

    Ibrahim, S.A.; Flot, S.L.

    1983-01-01

    The purpose of this study was to investigate the effect of barium chloride treatments on: reduction of 222 Rn emanation from mill wastes; reduction of 226 Ra levels in wastewater; and decreased leachability of 226 Ra from mill wastes. Baseline 226 Ra concentrations were determined for ore and tailings as well as radon emanation fractions. Uranium ore was treated with soluble barium at concentrations of 10, 25, 50, and 100 mg per litre of slurry. The leach-liquor declined in 226 Ra concentration by as much as 50%. When soluble potassium as well as barium was used in the treatment process at equal concentrations of 10, 25, 50, and 100 mg per litre of slurry, a similar reduction was observed. No significant difference was noted between the two treatment regimes. An accelerated leaching experiment was performed on the ore treated with barium chloride. All treatment groups except that treated with 10 mg of soluble barium per litre of slurry showed significant decreases in leachability. Available 222 Rn (corresponds with radon emanation fraction) was measured in treated and untreated ore. Ore treated with concentrations of Ba ++ up to 1.00 mg per gram of ore did not show a statistically significant reduction in available 222 Rn, however when potassium sulfate was also added, a significant decline was noted. This study suggests that barium chloride treatments reduce radon emanation from mill wastes and reduce 226 Ra levels in wastewater. Leachability of 226 Ra from treated samples decreased markedly. 19 references, 8 figures, 7 tables

  4. Magmatism and Eurekan deformation in the High Arctic Large Igneous Province: 40Ar–39Ar age of Kap Washington Group volcanics, North Greenland

    DEFF Research Database (Denmark)

    Tegner, Christian; Storey, Michael; Holm, Paul Martin

    2011-01-01

    The High Arctic Large Igneous Province is unusual on two counts: first, magmatism was prolonged and has been suggested to include an initial tholeiitic phase (130–80 Ma) and a second alkaline phase (85–60 Ma); second, it was subsequently deformed during the Eurekan Orogeny. New 40Ar–39Ar dating...... of alkaline volcanics from Kap Kane, part of the Kap Washington Group volcanics at the northern tip of Greenland, provides an emplacement age of 71.2±0.5 Ma obtained from amphibole in lapilli tuffs, and a thermal resetting age of 49–47 Ma obtained in feldspar and whole-rocks from trachyte flows. Patch...... in the Labrador Sea and the Baffin Bay, and to eastwards displacement of Greenland relative to North America. The alkaline suite, therefore, may be unrelated to the main tholeiitic phase of the High Arctic Large Igneous Province. The subsequent initiation of continental rifting and ensuing seafloor spreading...

  5. Genesis of Pb-Zn-Cu-Ag Deposits within Permian Carboniferous-Carbonate Rocks in Madina Regency, North Sumatra

    Directory of Open Access Journals (Sweden)

    Bhakti Hamonangan Harahap

    2015-09-01

    Full Text Available DOI:10.17014/ijog.2.3.167-184Strong mineralized carbonate rock-bearing Pb-Zn-Cu-Ag-(Au ores are well exposed on the Latong River area, Madina Regency, North Sumatra Province. The ore deposit is hosted within the carbonate rocks of the Permian to Carboniferous Tapanuli Group. It is mainly accumulated in hollows replacing limestone in the forms of lensoidal, colloform, veins, veinlets, cavity filling, breccia, and dissemination. The ores dominantly consist of galena (126 000 ppm Pb and sphalerite (2347 ppm Zn. The other minerals are silver, azurite, covellite, pyrite, marcasite, and chalcopyrite. This deposit was formed by at least three phases of mineralization, i.e. pyrite and then galena replaced pyrite, sphalerite replaced galena, and pyrite. The last phase is the deposition of chalcopyrite that replaced sphalerite. The Latong sulfide ore deposits posses Pb isotope ratio of 206Pb/204Pb = 19.16 - 20.72, 207Pb/204Pb = 16.16 - 17.29, and 208Pb/204Pb = 42.92 - 40.78. The characteristic feature of the deposit indicates that it is formed by a sedimentary process rather than an igneous activity in origin. This leads to an interpretation that the Latong deposit belongs to the Sedimentary Hosted Massive Sulfide (SHMS of Mississippi Valley-Type (MVT. The presence of SHMS in the island arc such as Sumatra has become controversial. For a long time, ore deposits in the Indonesian Island Arc are always identical with the porphyry and hydrothermal processes related to arc magmatism. This paper is dealing with the geology of Latong and its base metal deposits. This work is also to interpret their genesis as well as general relationship to the regional geology and tectonic setting of Sumatra.

  6. XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

    International Nuclear Information System (INIS)

    Omran, Mamdouh; Fabritius, Timo; Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A.; El-Aref, Mortada; Elmanawi, Abd El-Hamid

    2015-01-01

    Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe 2 O 3 and P 2 O 5 contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe 3+ ) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases

  7. Acid pre-treatment method for in situ ore leaching

    International Nuclear Information System (INIS)

    Mallon, R.G.; Braun, R.L.

    1975-01-01

    An acid leaching method is described for the recovery of a desired element from a subterranean rubblized body of primary ore containing the element and also having associated therewith a carbonate mineral wherein the rubblized ore body is flooded with an aqueous acidic solution in order to release carbon dioxide from the associated carbonate mineral. After a substantial portion of the available carbon dioxide is released and removed from the ore body, as by venting to the atmosphere, an oxidizing gas is introduced into the flooded, rubblized ore to oxidize the ore and form an acid leach solution effective in the presence of the dissolved oxidizing gas to dissolve the ore and cause the desired element to go into solution. The leach solution is then circulated to the surface where the metal values are recovered therefrom

  8. EXPLANATORY MODEL OF SPOT PRICE OF IRON ORE

    Directory of Open Access Journals (Sweden)

    Juan Enrique Villalva A.

    2015-11-01

    Full Text Available The objective of this study was to construct an explanatory model of the spot price of iron ore in the international market. For this, the method of multiple linear regressions was used. As a dependent variable, the spot price of iron ore (62% Fe China Tianjin port was taken, between 2010 and 2013. As independents variables were taken seven variables of international iron ore market. The resulting model includes variables: Iron ore inventory in Chinese ports, Baltic Dry Index (BDI, Iron ore exports from Brazil & Australia and Chinese Rebar Steel Price, as explanatory variables of the behavior of the spot price of iron ore in the international market. The model has an adjusted coefficient of determination R2 of 0.90, and was validated by comparing its predictions vs. known values of 2014.

  9. The stratigraphy of the Steep Rock Group, N.W. Ontario, with evidence of a major unconformity

    Science.gov (United States)

    Wilks, M. E.; Nisbet, E. G.

    1986-01-01

    The Steep Rock Group is exposed 6 km north of Atikokan, 200 km west of Thunder Bay. It is situated on the southern margin of the Wabigoon Belt of the Archaean Superior Province, N. W. Ontario. Reinvestigation of the geology of the Group has shown that the Group lies unconformably on the Tonalite Complex to the east. This unconformity has been previously suspected, from regional and ine mapping but no conclusive outcrop evidence for its existence has as yet been published. The strike of the group, comprised of Basal Conglomerate, Carbonate Member, Ore Zone and Ashrock is generally north-northwest dipping steeply to the southwest. Of the 7 contacts between the Steep Rock Group and the Tonalite Complex, 3 expose the unconformity (The Headland, S. Roberts Pit, Trueman Point), and 4 are faulted. These three outcrops demonstrate unequivocally that the Steep Rock group was laid down unconformably on the underlying Tonalite Complex, which is circa 3 Ga old.

  10. Cognitive function after radiotherapy for supratentorial low-grade glioma: A North Central Cancer Treatment Group prospective study

    International Nuclear Information System (INIS)

    Laack, Nadia N.; Brown, Paul D.; Ivnik, Robert J.; Furth, Alfred F. M.S.; Ballman, Karla V.; Hammack, Julie E.; Arusell, Robert M.; Shaw, Edward G.; Buckner, Jan C.

    2005-01-01

    Purpose: To evaluate the effects of cranial radiotherapy (RT) on cognitive function in patients with supratentorial low-grade glioma. Methods and Materials: Twenty adult patients with supratentorial low-grade glioma were treated with 50.4 Gy (10 patients) or 64.8 Gy (10 patients) localized RT. The patients then were evaluated with an extensive battery of psychometric tests at baseline (before RT) and at approximately 18-month intervals for as long as 5 years after completing RT. To allow patients to serve as their own controls, cognitive performance was evaluated as change in scores over time. All patients underwent at least two evaluations. Results: Baseline test scores were below average compared with age-specific norms. At the second evaluation, the groups' mean test scores were higher than their initial performances on all psychometric measures, although the improvement was not statistically significant. No changes in cognitive performance were seen during the evaluation period when test scores were analyzed by age, treatment, tumor location, tumor type, or extent of resection. Conclusions: Cognitive function was stable after RT in these patients evaluated prospectively during 3 years of follow-up. Slight improvements in some cognitive areas are consistent with practice effects attributable to increased familiarity with test procedures and content

  11. The late cretaceous Donlin Creek gold deposit, Southwestern Alaska: Controls on epizonal ore formation

    Science.gov (United States)

    Goldfarb, R.J.; Ayuso, R.; Miller, M.L.; Ebert, S.W.; Marsh, E.E.; Petsel, S.A.; Miller, L.D.; Bradley, D.; Johnson, Chad; McClelland, W.

    2004-01-01

    The Donlin Creek gold deposit, southwestern Alaska, has an indicated and inferred resource of approximately 25 million ounces (Moz) Au at a cutoff grade of 1.5 g/t. The ca. 70 Ma deposit is hosted in the Late Cretaceous Kuskokwim flysch basin, which developed in the back part of the are region of an active continental margin, on previously accreted oceanic terranes and continental fragments. A hypabyssal, mainly rhyolitic to rhyodacitic, and commonly porphyritic, 8- ?? 3-km dike complex, part of a regional ca. 77 to 58 Ma magmatic arc, formed a structurally competent host for the mineralization. This deposit is subdivided into about one dozen distinct prospects, most of which consist of dense quartz ?? carbonate veinlet networks that fill north-northeast-striking extensional fractures in the northeast-trending igneous rocks. The sulfide mineral assemblage is dominated by arsenopyrite, pyrite, and, typically younger, stibnite; gold is refractory within the arsenopyrite. Sericitization, carbonatization, and suffidation were the main alteration processes. Fluid inclusion studies of the quartz that hosts the resource indicate dominantly aqueous ore fluids with also about 3 to 7 mol percent CO2 ?? CH4 and a few tenths to a few mole percent NaCl + KCl. The gold-bearing fluids were mainly homogeneously trapped at approximately 275?? to 300??C and at depths of 1 to 2 km. Some of the younger stibnite may have been deposited by late-stage aqueous fluids at lower temperature. Measured ??18O values for the gold-bearing quartz range between 11 and 25 per mil; the estimated ??18O fluid values range from 7 to 12 per mil, suggesting a mainly crustally derived fluid. A broad range of measured ??D values for hydrothermal micas, between -150 and -80 per mil, is suggestive of a contribution from devolatilization of organic matter and/or minor amounts of mixing with meteoric fluids. Gold-associated hydrothermal sulfide minerals are characterized by ??34S values mainly between -16 and

  12. The identification of critical groups and its application to fish and shellfish consumers in the coastal area of the North-East Irish Sea

    International Nuclear Information System (INIS)

    Hunt, G.J.; Hewett, C.J.; Shepherd, J.G.

    1982-01-01

    Control of radioactive waste disposal to the environment, based on the recommendations of the International Commission on Radiological Protection (ICRP), necessitates an identification of the critical group of members of the public exposed from a given practice. Criteria for identification of critical groups based mainly on ICRP recommendations are discussed. Methods existing up to 1974 are briefly reviewed in the light of these criteria. Two more recent methods are described and compared on the basis of previous data; these methods, which are complementary, are based on homogeneity considerations and satisfy the criteria generally rather better than do the earlier methods. The application of the newer techniques to recent surveys of fish and shellfish consumption in the coastal area of the North-East Irish Sea is described, in relation to discharges from the Windscale reprocessing plant. The results of this survey are presented, and estimates are given of the effective dose equivalent to members of these critical groups in recent years, to show the effect of liquid discharges from Windscale in terms of public radiation exposure. (author)

  13. Separation of monazite from Rirang ore by floatation method

    International Nuclear Information System (INIS)

    Affandi, Kosim; Sjahminan, Mainar

    1995-01-01

    Separation of monazite from Rirang ore has been carried out by means of floatation using oleic acid and pine oil as promoter and frothier reagents, respectively. Several parameters affecting floatation process, i.e. grain size of the ore, pulp pH, and reagents concentration were examnined. The optimal conditions for the process include the use of -100 mesh feed ore, pulp pH 9.0 and 1 kilogram of each oleic acid and pine oil per tonne ore. Based on the conditions, monazite recovery of 90% was achieved with about 20% uranium remain in monazite concentrate. (author). 7 refs, 9tabs, 1 fig

  14. Testing of X-ray radiometric enrichnment of polymetallic ores

    International Nuclear Information System (INIS)

    Eliseev, N.I.; Panova, N.I.; Kirbitova, N.V.; Shramm, E.O.; Efremov, Yu.G.

    1987-01-01

    Testing of X-ray radiometric method of sorting of polymetallic ores using the developed X-ray radiometric device was conducted. It was shown that introduction of preliminary concentration at the factory made the method of fragment separation to be the perspective one, enabling to elevate the factory production with respect to commercial ore and reduce the cost of ore processing. In the case of preliminary concentration, conducted at the mine, it is advisable to perform ore sorting in the flow formed to monolayer

  15. IAEA sends out samples of uranium ore

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1966-06-15

    Full text: Governments and organizations interested in developing uranium resources will be assisted by a new service, now being inaugurated by the Agency's laboratories, for the distribution of reference samples of uranium ores. This is an addition to the service which began at Seibersdorf in January 1962 for the distribution of calibrated radionuclides, and which has met with a steadily increasing demand. * Uranium deposits consisting of ores with a uranium content in the range 0.5 - 0.05 per cent occur in a number of countries, including developing countries and can present considerable analytical difficulties. In 1962 the Agency asked Member States whether they would be interested in receiving reference samples of uranium ores to assist them in checking their methods of chemical analysis. The response encouraged the Agency to proceed. There is a multiplicity of types of uranium ores and, initially, three of the most commonly occurring have been selected - torbernite, uraninite and carnotite. Member States have provided the laboratory with supplies of these three types of ore. In order to determine the uranium content, samples are sent to leading laboratories throughout the world, so as to arrive at the most accurate values possible. This work has proved to be useful to the laboratories themselves ; in searching for reasons for discrepancies between the different collaborating laboratories, they enlarge their own knowledge and improve their methods. The reference samples are sent out in the form of fine powder, and are available to atomic energy commissions, research laboratories or mining companies. The requesting laboratory, having worked out the analytical process best suited to its needs, is then able to check its results by analysing an IAEA reference sample of known uranium content. By the end of 1966, reference samples will be available of the three ores mentioned, and later also of pure uranium oxide and of uranium oxide containing trace impurities, the

  16. The genesis of Kurišková U-Mo ore deposit

    International Nuclear Information System (INIS)

    Demko, R.; Biroň, A.; Novotný, L.; Bartalský, B.

    2014-01-01

    The U-Mo ores of the known uranium deposit Kurišková located in the Huta volcano-sedimentary complex (HVC) of lower Permian age belongs to the Petrova Hora Formation of the North-Gemeric tectonic unit (Western Carpathians). The HVC is built up by volcanic rocks of bimodal basalt-rhyolite association, intercalated with sandstones, mudstones and claystones. Based on the sedimentary facies reconstruction, it is supposed paleoenvironment of seasonally flooded shallow lakes of continental fluvial plain with transition to estuaries and shallow marine facies of continental shelf in the upper part of HVC.

  17. PHASE ANALYSES OF URANIUM BEARING MINERALS FROM THE HIGH GRADE ORE, NOPAL I, PENA BLANCA, MEXICO

    International Nuclear Information System (INIS)

    Ren, M.; Goodell, P.; Kelts, A.; Anthony, E.Y.; Fayek, M.; Fan, C.; Beshears, C.

    2005-01-01

    The Nopal I uranium deposit is located in the Pena Blanca district, approximately 40 miles north of Chihuahua City, Mexico. The deposit was formed by hydrothermal processes within the fracture zone of welded silicic volcanic tuff. The ages of volcanic formations are between 35 to 44 m.y. and there was secondary silicification of most of the formations. After the formation of at least part of the uranium deposit, the ore body was uplifted above the water table and is presently exposed at the surface. Detailed petrographic characterization, electron microprobe backscatter electron (BSE) imagery, and selected x-ray maps for the samples from Nopal I high-grade ore document different uranium phases in the ore. There are at least two stages of uranium precipitation. A small amount of uraninite is encapsulated in silica. Hexavalent uranium may also have been a primary precipitant. The uranium phases were precipitated along cleavages of feldspars, and along fractures in the tuff. Energy dispersive spectrometer data and x-ray maps suggest that the major uranium phases are uranophane and weeksite. Substitutions of Ca and K occur in both phases, implying that conditions were variable during the mineralization/alteration process, and that compositions of the original minerals have a major influence on later stage alteration. Continued study is needed to fully characterize uranium behavior in these semi-arid to arid conditions

  18. Bioprocessing of ores: Application to space resources

    Science.gov (United States)

    Johansson, Karl R.

    1992-01-01

    The role of microorganisms in the oxidation and leaching of various ores (especially those of copper, iron, and uranium) is well known. This role is increasingly being applied by the mining, metallurgy, and sewage industries in the bioconcentration of metal ions from natural receiving waters and from waste waters. It is concluded that bioprocessing using bacteria in closed reactors may be a variable option for the recovery of metals from the lunar regolith. Obviously, considerable research must be done to define the process, specify the appropriate bacteria, determine the necessary conditions and limitations, and evaluate the overall feasibility.

  19. Upgrading of boron ores and colemanite flotation

    International Nuclear Information System (INIS)

    Yarar, B.; Mager, J.

    1979-01-01

    Processes applied for the processing and upgrading of sodium and calcium borates in Turkey are described. Details of froth flotation study where a low grade colemanite ore containing calcite and clays as a gangue minerals are given. It has been found that, at the natural pH of a colemanite-containing pulp (pH=9,2) it is possible to float colemanite selectively using dodecyl benzene sulphonate or its combinations with a non-polar reagent or naphthenic acids. (author)

  20. Bacterial leaching of uranium ores - a review

    International Nuclear Information System (INIS)

    Lowson, R.T.

    1975-11-01

    The bacterial leaching of uranium ores involves the bacterially catalysed oxidation of associated pyrite to sulphuric acid and Fe 3+ by autotrophic bacteria and the leaching of the uranium by the resulting acidic, oxidising solution. Industrial application has been limited to Thiobacillus thiooxidans and Thiobacillus ferrooxidans at pH 2 to 3, and examples of these are described. The bacterial catalysis can be improved with nutrients or prevented with poisons. The kinetics of leaching are controlled by the bed depth, particle size, percolation rate, mineralogy and temperature. Current work is aimed at quantitatively defining the parameters controlling the kinetics and extending the method to alkaline conditions with other autotrophic bacteria. (author)

  1. ores - Fauna e flora - Contributo.

    OpenAIRE

    Furtado, Duarte

    1986-01-01

    Situado a mais de 1500 kilómetros da Europa à latitude de Lisboa, o arquipélago dos Açores de origem vulcânica estende-se ao longo dum eixo (SSE-NNW) por 600 kilómetros com nove ilhas repartidas por três grupos distinctos. Povoado nos meados do século XV pelos portugueses, a população actual é de 270.000 habitantes, aproximadamente. Uma origem recente e um vulcanismo muito activo, fazem com que os relevos sejam muito jovens, existindo em cada ilha uma ou mais caldeiras centrais. O clima...

  2. Lung cancer and inhaled uranium ore dust in rats

    International Nuclear Information System (INIS)

    Mitchel, R.E.J.; Jackson, J.S.

    1997-01-01

    Using a nose only inhalation system, 187 nine week old male Sprague-Dawley rats were exposed to two different concentrations of natural uranium ore dust aerosol (44% U) without significant radon content. Inhalation exposures averaged about 4.2 h/day, 5 days/week for 65 weeks at which point lung uranium burdens in the two groups averaged 0.9 and 1.9 mg/g dry weight. Animals (63) exposed to the air stream without dust served as controls. After inhalation exposure ceased, the rats were allowed to live for their natural lifetime, a maximum of about 900 days after the start of dust inhalation. Lung uranium burdens were measured at the time of death of each animal. Lung burdens were found to decline exponentially after dust inhalation ceased, and the rate of decline was independent of the initial lung burden. All lungs were examined at necropsy and histologically for lung tumors. Lung tumors of lung origin were observed in both exposed groups and in the control group. The frequency of primary malignant lung tumors was 0.016, 0.175 and 0.328 and primary non-malignant lung tumors 0.016, 0.135 and 0.131 in the control low and high aerosol exposed groups respectively. Absorbed dose to the lung was calculated for each animal in the study. The average maximum doses for all the animals exposed to the low or high concentration of dust aerosol were 0.87 Gy and 1.64 Gy respectively. The average risk of malignant lung tumors from inhaled natural uranium ore dust was therefore about 0.20 tumors/animal/Gy. For animals with lung tumors, the average doses were 0.98 and 1.90 in the exposed groups. In both exposed groups, the frequency of primary malignant or non-malignant lung tumors was significantly greater than in the control group (p < 0.02) and the frequency of primary malignant lung tumors in the two exposed group were significantly different from each other (p = 0.05). The frequency of primary lung tumors (malignant and non-malignant) was calculated as a function of dose

  3. Occupational Contact Dermatitis in North American Print Machine Operators Referred for Patch Testing: Retrospective Analysis of Cross-Sectional Data From the North American Contact Dermatitis Group 1998 to 2014.

    Science.gov (United States)

    Warshaw, Erin M; Hagen, Solveig L; Belsito, Donald V; DeKoven, Joel G; Maibach, Howard I; Mathias, C G Toby; Zug, Kathryn A; Sasseville, Denis; Zirwas, Matthew J; Fowler, Joseph F; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Taylor, James S

    Little is known about the epidemiology of contact dermatitis (CD) in print machine operators (PMOs). The aims of this study were to estimate the prevalence of CD and characterize clinically relevant and occupationally related allergens among PMOs undergoing patch testing. This was a retrospective cross-sectional analysis of the North American Contact Dermatitis Group data from 1998 to 2014. Of 39,332 patch-tested patients, 132 (0.3%) were PMOs. Among PMOs, most were male (75.0%) and white (92.4%). The majority were printing press operators (85.6%). The most frequent sites of dermatitis were hands (63.6%), arms (29.5%), and face/scalp (24.2%). More than half had an occupationally related skin condition (56.1%). Final diagnoses were most commonly allergic CD (58.3%) and irritant CD (33.3%). Cobalt (20.8%), carba mix (12.5%), thiuram mix (8.3%), and formaldehyde (8.3%) were the most frequent occupationally related allergens. The top allergen sources included inks (22.9%), gloves (20.8%), and coatings/dye/copy/photographic chemicals (14.6%). Allergic CD, irritant CD, and involvement of exposed body areas were common among PMOs. Common allergens included rubber accelerators, metals, and preservatives.

  4. Validation of Progression‐Free Survival as a Surrogate Endpoint for Overall Survival in Malignant Mesothelioma: Analysis of Cancer and Leukemia Group B and North Central Cancer Treatment Group (Alliance) Trials

    Science.gov (United States)

    Wang, Xiaoyi; Hodgson, Lydia; George, Stephen L.; Sargent, Daniel J.; Foster, Nate R.; Ganti, Apar Kishor; Stinchcombe, Thomas E.; Crawford, Jeffrey; Kratzke, Robert; Adjei, Alex A.; Kindler, Hedy L.; Vokes, Everett E.; Pang, Herbert

    2017-01-01

    Abstract Purpose. The aim of this study was to investigate whether progression‐free survival (PFS) can be considered a surrogate endpoint for overall survival (OS) in malignant mesothelioma. Materials and Methods. Individual data were collected from 15 Cancer and Leukemia Group B (615 patients) and 2 North Central Cancer Treatment Group (101 patients) phase II trials. The effects of 5 risk factors for OS and PFS, including age, histology, performance status (PS), white blood cell count, and European Organisation for Research and Treatment of Cancer (EORTC) risk score, were used in the analysis. Individual‐level surrogacy was assessed by Kendall's tau through a Clayton bivariate Copula survival (CBCS) model. Summary‐level surrogacy was evaluated via the association between logarithms of the hazard ratio (log HR)—log HROS and log HRPFS—measured in R2 from a weighted least‐square (WLS) regression model and the CBCS model. Results. The median PFS for all patients was 3.0 months (95% confidence interval [CI], 2.8–3.5 months) and the median OS was 7.2 months (95% CI, 6.5–8.0 months). Moderate correlations between PFS and OS were observed across all risk factors at the individual level, with Kendall's tau ranging from 0.46 to 0.47. The summary‐level surrogacy varied among risk factors. The Copula R2 ranged from 0.51 for PS to 0.78 for histology. The WLS R2 ranged from 0.26 for EORTC and PS to 0.67 for age. Conclusions. The analyses demonstrated low to moderate individual‐level surrogacy between PFS and OS. At the summary level, the surrogacy between PFS and OS varied significantly across different risk factors. With a short postprogression survival and a moderate correlation between PFS and OS, there is no evidence that PFS is a valid surrogate endpoint for OS in malignant mesothelioma. Implications for Practice. For better disease management and for more efficient clinical trial designs, it is important to know if progression‐free survival (PFS) is

  5. The Application of Artificial Neural Networks to Ore Reserve Estimation at Choghart Iron Ore Deposit

    Directory of Open Access Journals (Sweden)

    Seyyed Ali Nezamolhosseini

    2017-01-01

    Full Text Available Geo-statistical methods for reserve estimation are difficult to use when stationary conditions are not satisfied. Artificial Neural Networks (ANNs provide an alternative to geo-statistical techniques while considerably reducing the processing time required for development and application. In this paper the ANNs was applied to the Choghart iron ore deposit in Yazd province of Iran. Initially, an optimum Multi Layer Perceptron (MLP was constructed to estimate the Fe grade within orebody using the whole ore data of the deposit. Sensitivity analysis was applied for a number of hidden layers and neurons, different types of activation functions and learning rules. Optimal architectures for iron grade estimation were 3-20-10-1. In order to improve the network performance, the deposit was divided into four homogenous zones. Subsequently, all sensitivity analyses were carried out on each zone.  Finally, a different optimum network was trained and Fe was estimated separately for each zone. Comparison of correlation coefficient (R and least mean squared error (MSE showed that the ANNs performed on four homogenous zones were far better than the nets applied to the overall ore body. Therefore, these optimized neural networks were used to estimate the distribution of iron grades and the iron resource in Choghart deposit. As a result of applying ANNs, the tonnage of ore for Choghart deposit is approximately estimated at 135.8 million tones with average grade of Fe at 56.14 percent. Results of reserve estimation using ANNs showed a good agreement with the geo-statistical methods applied to this ore body in another work.

  6. Sedimentary exhalative nickel-molybdenum ores in south China

    Science.gov (United States)

    Lott, D.A.; Coveney, R.M.; Murowchick, J.B.; Grauch, R.I.

    1999-01-01

    Unique bedded Ni-Mo ores hosted by black shales were discovered in localized paleobasins along the Yangzte platform of southern China in 1971. Textural evidence and radiometric dates imply ore formation during sedimentation of black shales that grade into readily combustible beds, termed stone coals, which contain 10 to 15 percent organic carbon. Studies of 427 fluid inclusions indicate extreme variation in hydrothermal brine salinities that were contained by Proterozoic dolostones underlying the ore zone in Hunan and Guizhou. Variations of fluid inclusion salinities, which range from 0.1 to 21.6 wt percent NaCl equiv, are attributed to differences in the compositions of brines in strata underlying the ore bed, complicated by the presence of seawater and dilute fluids that represent condensates of vapors generated by boiling of mineralizing fluids or Cambrian meteoric water. The complex processes of ore deposition led to scattered homogenization temperatures ranging from 100??to 187??C within the Hunan ore zone and from 65??to 183??C within the Guizhou ore zone. While living organisms probably did not directly accumulate metals in situ in sufficient amounts to explain the unusually high grades of the deposits, sulfur isotope ratios indicate that bacteria, now preserved as abundant microfossils, provided sufficient sulfide for the ores by reduction of seawater sulfate. Such microbiota may have depended on vent fluids and transported organic matter for key nutrients and are consistent with a sedex origin for the ores. Vent fluids interacted with organic remains, including rounded fragments of microbial mats that were likely transported to the site of ore deposition by the action of waves and bottom currents prior to replacement by ore minerals.

  7. Bacterial leaching of pyritic gold ores

    Energy Technology Data Exchange (ETDEWEB)

    Gagliardi, F.M.; Cashion, J.D.; Brown, L.J. [Monash Univ., Clayton, VIC (Australia). Dept. of Physics; Jay, W.H. [Monash Univ., Clayton, VIC (Australia). Chemical Engineering Department

    1996-12-31

    The bacterial oxidation process is well known in nature but has only recently come under investigation as a viable and relatively clean method of gold recovery from ores. However there is currently little information about the process at an atomic scale. It is known that the bacterial attack progresses preferentially along grain boundaries which is precisely where the gold has been deposited from aqueous infiltration. Samples have been obtained from the Wiluna mine in Western Australia consisting of the original ore, 2 pre-treatments, and from six successive bacterial reactors. {sup 57}Fe Moessbauer spectra taken at room temperature show only two quadrupole split doublets which can be ascribed to pyrite, FeS{sub 2}, and arsenopyrite, FeAsS. However, the presence of any superparamagnetic oxide or oxyhydroxide species would be expected to give a spectrum very similar to that of pyrite and would be undetectable in small quantities. At a temperature of 5K, a broad magnetically split sextet is observable with a mean hyperfine field of approximately 50T. This field is characteristic of magnetically ordered ferric iron surrounded by an octahedron of oxygens. The intensity and characteristics of this subspectrum alters through the series and interpretations will be given on the oxidation products of the bacterial leaching

  8. Bacterial leaching of pyritic gold ores

    International Nuclear Information System (INIS)

    Gagliardi, F.M.; Cashion, J.D.; Brown, L.J.; Jay, W.H.

    1996-01-01

    The bacterial oxidation process is well known in nature but has only recently come under investigation as a viable and relatively clean method of gold recovery from ores. However there is currently little information about the process at an atomic scale. It is known that the bacterial attack progresses preferentially along grain boundaries which is precisely where the gold has been deposited from aqueous infiltration. Samples have been obtained from the Wiluna mine in Western Australia consisting of the original ore, 2 pre-treatments, and from six successive bacterial reactors. 57 Fe Moessbauer spectra taken at room temperature show only two quadrupole split doublets which can be ascribed to pyrite, FeS 2 , and arsenopyrite, FeAsS. However, the presence of any superparamagnetic oxide or oxyhydroxide species would be expected to give a spectrum very similar to that of pyrite and would be undetectable in small quantities. At a temperature of 5K, a broad magnetically split sextet is observable with a mean hyperfine field of approximately 50T. This field is characteristic of magnetically ordered ferric iron surrounded by an octahedron of oxygens. The intensity and characteristics of this subspectrum alters through the series and interpretations will be given on the oxidation products of the bacterial leaching

  9. Juuru Mihkli Kiriku Oreli Fond võttis endale uue ülesande / Tauno Kibur

    Index Scriptorium Estoniae

    Kibur, Tauno

    2009-01-01

    Oreli fond on võtnud ülesandeks restaureerida koguduse ajalooline pastoraat. Hoone eskiisi tegi Raivi Juks. Oreli restaureerimist ja tulemust jääb fikseerima Juuru oreli plaat, mille muusikapalad mängis sisse Kristel Aer

  10. 40 CFR 440.20 - Applicability; description of the aluminum ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... subpart B are applicable to discharges from facilities engaged in the mining of bauxite as an aluminum ore. ... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Aluminum Ore...

  11. Developments of uranium and gold ores heap leaching technologies

    International Nuclear Information System (INIS)

    Tian Yuan; Guan Zibin; Gao Renxi

    1998-01-01

    The author reviews developments in heap leaching of uranium and gold ores at home and abroad, summarises condition of application. The author also presents problems having to be studied and settled urgently in heap leaching of uranium and gold ores in China

  12. Waste monitoring of the uranium ore processing activities in Romania

    International Nuclear Information System (INIS)

    Nica, L.

    2002-01-01

    The uranium ore processing activities at the Feldioara site produce a range of liquid and solid waste that are monitored. Liquids are treated through decantation, pH correction and uranium precipitation before their release into the environment. The solid waste is gathered into ore specific area and are covered regularly with clay materials. (author)

  13. Arsenic bioleaching in medical realgar ore and arsenicbearing ...

    African Journals Online (AJOL)

    However, the maximum arsenic leaching ratio from realgar in the presence of mixed unadapted strains was only 12.4 %. Besides, maximum arsenic leaching ratios from arsenic-bearing refractory gold ore by mixed adapted strains or unadapted strains were 45.0 and 22.9 %, respectively. Oxidation of these two ores by ...

  14. Treatment of bastnaesite ore from Vietnamese Socialist Republic

    International Nuclear Information System (INIS)

    Formanek, J.; Jerabek, J.; Jancarek, J.

    1987-01-01

    From the Vietnamese deposit at Nam Nam Xe Czechoslovakia imported several hundred tons of ore. Several methods of ore dressing were used: gravitational, preconcentration in electromagnetic field, magnetic separation, high-intesity electromagnetic separation. Flotation evidently was the best dressing method tried. The results are presented of testing using different flotation agents. (E.S.)

  15. Some aspects of the processing development for uranium ores treatment

    International Nuclear Information System (INIS)

    Bruno, J.B.

    1982-01-01

    It is discussed the methodology adopted by NUCLEBRAS to the processing development for uranium ores treatment. The used methodology has the following steps: exploratories studies, preliminaries stiudies and optimization studies. The studies include physical and chemical contained in the solution. As examples are cited the uranium ores treatment in Lagoa Real and Itataia. (A.B.) [pt

  16. Ore reserve estimation of uranium deposit Zirovski vrh

    International Nuclear Information System (INIS)

    Lukacs, E.

    1979-01-01

    The uranium ore deposit Zirovski vrh is in the Permian sediments of Northwest Yugoslavia. Lenticular bodies occur at several stratiform levels in grey, medium-grained sandstone. The ore deposit will be mined entirely by underground methods. It is possible to define three stages of deposit evaluation requiring different densities of exploration effort: preliminary evaluation of in situ ore reserves; evaluation of mineable ore reserves; evaluation of production capability and mine planning. The drilling density increases markedly with each succeeding stage. The optimal drilling density for all three stages of evaluation should be determined, but there is some concern that too close spaced drilling would considerably increase the exploration costs without a corresponding increase in effectiveness. On the other hand, too sparsely spaced drilling may result in some difficulties in following the ore in mining. The paper treats the problem of the density of drilling for evaluation of mineable ore reserves compared to that required for mine planning and mine production capability. The purpose of investigation of mineral raw materials is to define economic deposits (ore bodies). To evaluate the deposit economically an accurate reserve estimate is required. If it is accordingly established that such an estimate is within the degree of admissible error, the purpose of the exploration is satisfied. However, the problem as to whether the drilling grid is sufficiently dense remains, because the majority of estimates of ore reserves do not provide a measure of the reliability of the estimate. (author)

  17. The southwestern extension of the Jiao-Liao-Ji belt in the North China Craton: Geochronological and geochemical evidence from the Wuhe Group in the Bengbu area

    Science.gov (United States)

    Liu, Chaohui; Zhao, Guochun; Liu, Fulai; Cai, Jia

    2018-04-01

    The Wuhe complex is located at the southeastern margin of the North China Craton. The complex consists of metamorphosed Paleoproterozoic potassic granitoids and supracrustal rocks, of which the latter include the Fengyang and Wuhe groups. Meta-mafic rocks from the lower Wuhe Group have igneous zircon U-Pb ages of 2126 ± 37 Ma with εHf(t) values of -6.22 to +8.38, and xenocrystic zircons of 2.39-2.36 Ga, 2.55-2.54 Ga and 2.77-2.69 Ga. Geochemically, the meta-mafic rocks can be classified into two groups. Group 1 island arc tholeiites display flat to slightly right declined REE patterns and moderately negative Nb, Ta, Zr, and Ti anomalies. Group 2 mature arc calcalkaline basalts display strongly fractionated chondrite-normalized REE patterns and evidently negative Nb, Ta and Ti anomalies. These meta-mafic rocks formed by partial melting of sub-arc depleted mantle wedge which had been modified by slab-derived melts at an active continental margin. Depositional age of the group can be constrained in the period of 2.16-2.10 Ga based on ages of the youngest detrital zircons and latter intrusions. U-Pb ages of detrital zircons yield major age peaks of 2.69 Ga and 2.52 Ga, with minor peaks at 2.88 Ga, 2.78 Ga, 2.35 Ga and 2.17 Ga, most of which are derived from the late Mesoarchean to early Paleoproterozoic granitoids in the Wuhe complex and the Jiaodong Terrane. Metamorphic zircons in the marbles coexisting with garnet amphibolites or granulites occur as either single grains or overgrowth (or recrystallization) rims surrounding magmatic zircon cores and yield ages of 1882 ± 19 Ma to 1844 ± 15 Ma. The comparable ca. 2.1 Ga potassic granites with A-type granite affinity, the ca. 2.1 Ga meta-mafic rocks with arc-like geochemical features, the 2.1-1.9 Ga meta-sedimentary units and the 1.9-1.8 Ga subduction- and collision-related granulite-facies metamorphism suggest that the Wuhe complex and the Jiao-Liao-Ji Belt share the same late Paleoproterozoic tectonic evolution

  18. Influence of radon-daughter exposure rate and uranium ore dust concentration on occurrence of lung tumors

    International Nuclear Information System (INIS)

    Cross, F.T.; Palmer, R.F.; Busch, R.H.

    1980-01-01

    Groups of male SPF Wistar rats were exposed concurrently to several levels of radon daughters and uranium ore dust to study the effect of these variables on pulmonary disease states. Clinical pathology data at 1 yr postexposure indicate no significant differences among exposed animals when compared with controls. Preliminary histopathologic data suggest a trend toward increasing lung tumor risk as the exposure rate is decreased (constant total dose), but the differences are not statistically significant at the 0.05 level. A similar trend occurs with decrease in ore dust concentration (except for the 2560-WLM exposure group), but these differences are also not significant at the 0.05 level. The tumor risk is significantly (0.05 level) increased as the exposure level increases from approximately 320 and 640 WLM to 2560 WLM at the high ore dust concentration

  19. Semi-continuous on-line uranium ore analyzer

    International Nuclear Information System (INIS)

    Campbell, P.; Gurdy, E.M.; Hatchowski, L.

    1984-01-01

    The efficient process control of a uranium mill and its associated mining operation requires a nearly continuous knowledge of the uranium concentration in the ore. Generally, the approach is to use laboratory assays of grab samples from the mill feed belt. In some cases, elaborate and expensive systems have been used to ensure random sampling, but even with these systems, mass-balance discrepancies still exist. There is a requirement for an on-line instrument that can give a prompt, accurate analysis of a large portion of the feed stock. The authors have recently evaluated a laboratory system that achieves these goals using neutron activation and delayed neutron counting. The development of the on-line uranium ore analyzer is a consequence of previous work done at the Whiteshell Nuclear Research Establishment (WNRE) (Campbell et al., 1978 and 1981), and is based on the emission of delayed neutrons after the neutron irradiation of fissionable materials. The mechanism of delayed neutron emission has been described (Keepin, 1965), but briefly is as follows. The fission fragments resulting from irradiation are in an excited state. Certain of these delayed fission products, precursors, decay to a more stable state by the emission of a delayed neutron. The delayed neutrons can be divided into six groups with effective half-lives ranging from 0.2-55 sec. It is important to note that more than 50% of the delayed neutrons are emitted within the first 6 sec after irradiation; this has an influence on the design of the analysis instrument

  20. Study On Beneficiation Technology Of Dong Pao Rare-Earth-Barite-Fluorite With Two Product Plans About Content And Recovery Of Rare-Earth Fine Ores

    International Nuclear Information System (INIS)

    Duong Van Su; Truong Thi Ai; Bui Ba Duy; Bui Thi Bay; Nguyen Hong Ha; Le Thi Hong Ha; Doan Thi Mo; Doan Dac Ban; Nguyen Hoang Son

    2014-01-01

    The ore sample used in the research was taken from the F3 ore bodies and the sample of the F7, F9 and F16 ore bodies which contain the average of 5.98% TR 2 O 3 ; they are multi-metals ore which is difficult to enrich, highly weather with very complex ingredients. The process of the experiment is the ore is crushed, ground, screened and classified reasonably to -0.1 mm and divided into 3 particle size with the following technique: (1) -0.020 mm is primary sludge and the rare-earth fine ore; (2) 0.075-1 mm is gotten through the sludge concentrating table with the output is the 2 parts: the heavy part which is dried magnetic separator with high magnetism to get the rare-earth fine ore and the light one; (3) Light minerals, non-magnetic and ferromagnetic minerals group are ground together to 85% of them get size within -0.075 mm then mix it with 0.020-0.075 mm group. Using flotation separator, get barite-rare earth mixture and fluorite. After that, we separate this mixture by secondary flotation and get refined rare earth, barite and fluorite mineral. The result of the theme: (1) product plan A-rare-earth fine ore has TR 2 O 3 content archive 42.07% with recovery is 69.70%; (2) product plan B-rare-earth fine ore has TR 2 O 3 content archive 29.64% with recovery is 80.01%. (author)

  1. Detection of Babesia Sp. EU1 and members of spotted fever group rickettsiae in ticks collected from migratory birds at Curonian Spit, North-Western Russia.

    Science.gov (United States)

    Movila, Alexandru; Reye, Anna L; Dubinina, Helen V; Tolstenkov, Oleg O; Toderas, Ion; Hübschen, Judith M; Muller, Claude P; Alekseev, Andrey N

    2011-01-01

    To reveal the prevalence of spotted fever group (SFG) rickettsiae and Babesia sp. in Ixodes ricinus (L.) ticks from migratory birds, 236 specimens represented 8 species of Passeriformes and were collected at Curonian Spit in Kaliningrad enclave of North-Western Russia. The ticks (total 126) being detached from four bird species, Turdus philomelos, Fringilla coelebs, Parus major, and Sturnus vulgaris, were investigated by PCR using the primers Rp CS.877p/Rp CS.1258n for the detection of Rickettsia and BJ1/BN2 for Babesia spp. Babesia spp. were detected in 2 of 126 (1.6%) ticks. The partial sequence of 18S rDNA had 100% similarity to human pathogenic Babesia sp. EU1. The SFG rickettsiae were detected in 19 of 126 (15.1%) ticks collected from the above-mentioned bird species. BLAST analysis of SFG rickettsia gltA assigned sequences to human pathogenic Rickettsia helvetica (10.3%), Rickettsia monacensis (3.9%), and Rickettsia japonica (0.8%) with 98%-100% sequence similarity. The SFG rickettsiae and Babesia sp. EU1 in ticks collected from the passerines in Russia were detected for the first time. The survey indicates that migratory birds may become a reservoir for Babesia spp. and SFG rickettsiae. Future investigations need to characterize the role of birds in the epidemiology of these human pathogens in the region.

  2. Results of cytogenetic examinations of miners exposed to radon in ore mines

    International Nuclear Information System (INIS)

    Beno, M.; Vladar, M.; Nikodemova, D.; Vicanova, M.

    1998-01-01

    In this study the radon air concentrations and clastogenic effects at three ore mines located in central east Slovakia, the gold mine of Hodrusa-Hamre, talcum mine of Hnusta, and iron ore mine in Nizna Slana are compared with the chromosomal aberrations observed in a control group of healthy men which experienced underground work. A random sample of radon concentration measurements in houses was used for control. Significant differences in counts of aberrations of the chromosomal type in lymphocytes of smoker-miners of Nizna Slana as compared with counts of such aberrations in lymphocytes of a control group of similar age were found. A dependence of chromosomal aberration counts from the underground exposure to radon by multiple regression procedures could not be ascertained. The results indicated that confounding of such dependence by smoking might have taken place

  3. Discussion on uranium ore-formation age in Xiazhuang ore-field, northern Guangdong

    International Nuclear Information System (INIS)

    Wu Lieqin; Tan Zhengzhong; Liu Ruzhou; Huang Guolong

    2003-01-01

    There exist two genetic types of granite-type uranium deposits, i.e. the early-stage one, and the late-stage one. The early-stage uranium deposits are characterized by ore-formation ages of 122-138 Ma, and are high-grade uranium deposits of postmagmatic hydrothermal origin. The late-stage uranium deposits have ore-formation ages of 54-96 Ma. They mostly are low-grade uranium deposits, and of hydrothermal-regeneration origin with the uranium source derived from the mobilization of consolidated rocks. The early-stage uranium deposits should be the main target of further prospecting for high-grade uranium deposits in the region

  4. Summary of the mineralogy of the Colorado Plateau uranium ores

    Science.gov (United States)

    Weeks, Alice D.; Coleman, Robert Griffin; Thompson, Mary E.

    1956-01-01

    In the Colorado Plateau uranium has been produced chiefly from very shallow mines in carnotite ores (oxidized vanadiferous uranium ores) until recent deeper mining penetrated black unoxidized ores in water-saturated rocks and extensive exploration has discovered many deposits of low to nonvanadiferous ores. The uranium ores include a wide range from highly vanadiferous and from as much as one percent to a trace of copper, and contain a small amount of iron and traces of lead, zinc, molybdenum, cobalt, nickel, silver, manganese, and other metals. Recent investigation indicates that the carnotite ores have been derived by progressive oxidation of primary (unoxidized) black ores that contain low-valent uranium and vanadium oxides and silicates. The uranium minerals, uraninite and coffinite, are associated with coalified wood or other carbonaceous material. The vanadium minerals, chiefly montroseite, roscoelite, and other vanadium silicates, occur in the interstices of the sandstone and in siltstone and clay pellets as well as associated with fossil wood. Calcite, dolomite, barite and minor amounts of sulfides, arsenides, and selenides occur in the unoxidized ore. Partially oxidized vanadiferous ore is blue black, purplish brown, or greenish black in contrast to the black or dark gray unoxidized ore. Vanadium combines with uranium to form rauvite. The excess vanadium is present in corvusite, fernandinite, melanovanadite and many other quadrivalent and quinquevalent vanadium minerals as well as in vanadium silicates. Pyrite and part or all of the calcite are replaced by iron oxides and gypsum. In oxidized vanadiferous uranium ores the uranium is fixed in the relatively insoluble minerals carnotite and tyuyamunite, and the excess vanadium commonly combines with one or more of the following: calcium, sodium, potassium, magnesium, aluminum, iron, copper, manganese, or barium, or rarely it forms the hydrated pentoxide. The relatively stable vanadium silicates are little

  5. Implications of XRCC1, XPD and APE1 gene polymorphism in North Indian population: a comparative approach in different ethnic groups worldwide.

    Science.gov (United States)

    Gangwar, Ruchika; Manchanda, Parmeet Kaur; Mittal, Rama Devi

    2009-05-01

    Identifying risk factors for human cancers should consider combinations of genetic variations and environmental exposures. Several polymorphisms in DNA repair genes have impact on repair and cancer susceptibility. We focused on X-ray repair cross-complementing group 1 (XRCC1), Xeroderma pigmentosum D (XPD) and apurinic/apyrimidinic endonuclease (APE1) as these are most extensively studied in cancer. Present study was conducted to determine distribution of XRCC1 C26304T, G27466A, G23591A, APE1 T2197G and XPD A35931C gene polymorphisms in North Indian population and compare with different populations globally. PCR-based analysis was conducted in 209 normal healthy individuals of similar ethnicity. Allelic frequencies in wild type of XRCC1 C26304T were 91.1% C(Arg); G27466A 62.9% G(Arg); G23591A 60.3% G(Arg); APE1 T2197G 75.1% T(Asp) and XPD A35931C 71.8% A(Lys). The variant allele frequency were 8.9% T(Trp) in XRCC1 C26304T; 37.1% A(His) in G27466A; 39.7% A(Gln) in G23591A; 24.9% G(Glu) in APE1 and 28.2% C(Gln) in XPD respectively. We further compared frequency distribution for these genes with various published studies in different ethnicity. Our results suggest that frequency in these DNA repair genes exhibit distinctive pattern in India that could be attributed to ethnicity variation. This could assist in high-risk screening of humans exposed to environmental carcinogens and cancer predisposition in different ethnic groups.

  6. TEXTURAL DESCRIPTORS FOR MULTIPHASIC ORE PARTICLES

    Directory of Open Access Journals (Sweden)

    Laura Pérez-Barnuevo

    2012-11-01

    Full Text Available Monitoring of mineral processing circuits by means of particle liberation analysis through quantitative image analysis has become a routine technique within the last decades. Usually, liberation indices are computed as weight proportions, which is not informative enough when complex texture ores are treated by flotation. In these cases, liberation has to be computed as phase surface exposed to reactants, and textural relationships between minerals have to be characterized to determine the possibility of increasing exposure. In this paper, some indices to achieve a complete texture characterization have been developed in terms of 2D phase contact and mineral surfaces exposure. Indices suggested by other authors are also compared. The response of this set of parameters against textural changes has been explored on simple synthetic textures ranging from single to multiple inclusions and single to multiple veins and their ability to discriminate between different textural features is analyzed over real mineral particles with known internal structure.

  7. Alternative leaching processes for uranium ores

    International Nuclear Information System (INIS)

    Ring, R.J.

    1979-01-01

    Laboratory studies have been carried out to compare the extraction of uranium from Australian ores by conventional leaching in sulphuric acid with that obtained using hydrochloric acid and acidified ferric sulphate solutions. Leaching with hydrochloric acid achieved higher extractions of radium-226 but the extraction of uranium was reduced considerably. The use of acidified ferric sulphate solution reduced acid consumption by 20-40% without any detrimental effect on uranium extraction. The ferric ion, which is reduced during leaching, can be reoxidized and recycled after the addition of acid makeup. Hydrogen peroxide was found to be an effective oxidant in conventional sulphuric acid leaching. It is more expensive than alternative oxidants, but it is non-polluting, lesser quantities are required and acid consumption is reduced

  8. Management of wastes from the refining and conversion of uranium ore concentrate to uranium hexafluoride

    International Nuclear Information System (INIS)

    1981-01-01

    This report is the outcome of an IAEA Advisory Group Meeting on ''Waste Management Aspects in Relation to the Refining of Uranium Ore Concentrates and their Conversion to Uranium Hexafluoride'', which was held in Vienna from 17 to 21 December 1979. The report summarizes the main topics discussed at the meeting and gives an overview of uranium refining processes, being used in nuclear industry. The meeting was organized by the International Atomic Energy Agency, Radioactive Waste Management Section

  9. Ore minerals textural characterization by hyperspectral imaging

    Science.gov (United States)

    Bonifazi, Giuseppe; Picone, Nicoletta; Serranti, Silvia

    2013-02-01

    The utilization of hyperspectral detection devices, for natural resources mapping/exploitation through remote sensing techniques, dates back to the early 1970s. From the first devices utilizing a one-dimensional profile spectrometer, HyperSpectral Imaging (HSI) devices have been developed. Thus, from specific-customized devices, originally developed by Governmental Agencies (e.g. NASA, specialized research labs, etc.), a lot of HSI based equipment are today available at commercial level. Parallel to this huge increase of hyperspectral systems development/manufacturing, addressed to airborne application, a strong increase also occurred in developing HSI based devices for "ground" utilization that is sensing units able to play inside a laboratory, a processing plant and/or in an open field. Thanks to this diffusion more and more applications have been developed and tested in this last years also in the materials sectors. Such an approach, when successful, is quite challenging being usually reliable, robust and characterised by lower costs if compared with those usually associated to commonly applied analytical off- and/or on-line analytical approaches. In this paper such an approach is presented with reference to ore minerals characterization. According to the different phases and stages of ore minerals and products characterization, and starting from the analyses of the detected hyperspectral firms, it is possible to derive useful information about mineral flow stream properties and their physical-chemical attributes. This last aspect can be utilized to define innovative process mineralogy strategies and to implement on-line procedures at processing level. The present study discusses the effects related to the adoption of different hardware configurations, the utilization of different logics to perform the analysis and the selection of different algorithms according to the different characterization, inspection and quality control actions to apply.

  10. Direct Biohydrometallurgical Extraction of Iron from Ore

    Energy Technology Data Exchange (ETDEWEB)

    T.C. Eisele

    2005-10-01

    A completely novel approach to iron extraction was investigated, based on reductive leaching of iron by anaerobic bacteria. Microorganisms were collected from an anaerobic bog where natural seepage of dissolved iron was observed. This mixed culture was used to reduce insoluble iron in a magnetite ore to the soluble ferrous (Fe{sup +2}) state. While dissolution rates were slow, concentrations of dissolved iron as high as 3487 mg/l could be reached if sufficient time was allowed. A factorial study of the effects of trace nutrients and different forms of organic matter indicated that the best dissolution rates and highest dissolved iron concentrations were achieved using soluble carbohydrate (sucrose) as the bacterial food source, and that nutrients other than nitrogen, phosphorus, potassium, sodium, and acetate were not necessary. A key factor in reaching high levels of dissolved iron was maintaining a high level of carbon dioxide in solution, since the solubility of iron carbonates increases markedly as the quantity of dissolved carbon dioxide increases. Once the iron is dissolved, it has been demonstrated that the ferrous iron can then be electroplated from solution, provided that the concentration of iron is sufficiently high and the hydrogen ion concentration is sufficiently low. However, if the leaching solution is electrolyzed directly, organic matter precipitates at the cathode along with the metallic iron. To prevent this problem, the ferrous iron should be separated from the bulk solution in a more concentrated, purified form. One route to accomplishing this is to take advantage of the change in solubility of ferrous iron as a function of carbon dioxide concentration. By cycling the concentration of carbon dioxide in solution, it is possible to produce an iron-rich concentrate that should be suitable for electrolysis. This represents the first viable hydrometallurgical method for leaching iron directly from ore and producing metallic iron.

  11. Chlorine/chloride based processes for uranium ores

    International Nuclear Information System (INIS)

    1980-11-01

    The CE Lummus Minerals Division was commissioned by The Department of Supply and Services to develop order-of-magnitude capital and operating cost estimates for chlorine/chloride-based processes for uranium ores. The processes are designed to remove substantially all radioactive consituents from the ores to render the waste products harmless. Two processes were selected, one for a typical low grade ore (2 lb. U 3 O 8 /ton ore) and one for a high grade ore (50 lbs U 3 O 8 /ton). For the low grade ore a hydrochloric acid leaching process was chosen. For high grade ore, a more complex process, including gaseous chlorination, was selected. Capital cost estimates were compiled from information obtained from vendors for the specified equipment. Building cost estimates and the piping, electrical and instrumentation costs were developed from the plant layout. Utility diagrams and mass balances were used for estimating utilities and consumables. Detailed descriptions of the bases for capital and operating cost estimates are given

  12. Aqueous-chlorine leaching of typical Canadian uranium ores

    International Nuclear Information System (INIS)

    Haque, K.E.

    1982-01-01

    Laboratory-scale aqueous-chlorine leaches were conducted on quartz-pebble conglomerates, pegmatite and vein-type ores. Optimum leach temperatures, pulp density and retention times were determined. Uranium extraction of 98 per cent was obtained from the Elliot Lake, Madawaska Mines of Bancroft and Rabbit Lake ores, 96 per cent from the Key Lake ore and 86 per cent from the Agnew Lake ore. However, tailings containing 15-20 pCi g -1 of radium-226 were obtained only from the Elliot Lake and Agnew lake quartz-pebble conglomerates and Bancroft pegmatite-type ores by second-stage leaches with HCl. The second-stage leach results indicate that multistage (3 or 4) acid-chloride or salt-chloride leaches might be effective to obtain tailings containing 15-20 pCi 226 Ra g -1 from the high-grade vein-type ores. Comparative reagent-cost estimates show that the sulphuric-acid leach process is far less expensive than aqueous chlorine leaching. Nevertheless, only the aqueous chlorine and acid-chloride leaches in stages are effective in producing tailings containing 15-20 pCi 226 Ra g -1 from the typical Canadian uranium ores. (Auth.)

  13. Multi-column bioleaching of a uranium ore

    International Nuclear Information System (INIS)

    Meng Yunsheng; Zheng Ying; Liu Hui; Cheng Hao

    2014-01-01

    The technology of bioleaching uranium ore can increase the uranium leaching rate and shorten the leaching uranium period, save consumption of acid and oxidant, lower production costs. An experiment on multi-column bioleaching of a uranium ore was done using mesophilic bacteria, the average uranium recovery of 90% was achieved in 39 days. Compared with traditional process, leaching period was shortened to 39 d from 59 d, acid consumption and liquid-solid ratio were also reduced. The results showed it is suitable to bioleach the uranium ore. (authors)

  14. Mining and processing of uranium ores in the USSR

    International Nuclear Information System (INIS)

    Laskorin, B.N.; Mamilov, V.A.; Korejsho, Yu.A.

    1983-01-01

    Experience gained in uranium ore mining by modern methods in combination with underground and heap leaching is summarized. More intensive processing of low-grade ores has been achieved through the use of autoclave leaching, sorptive treatment of thick pulps, extractive separation of pure uranium compounds, automated continuous sorption devices of high efficiency for processing the underground- and heap-leaching liquors, natural and mine water, and recovery of molybdenum, vanadium, scandium, rare earths and phosphate fertilizers from low-grade ores. Production of ion-exchangers and extractants has been developed and processes for concomitant recovery of copper, gold, ionium, tungsten, caesium, zirconium, tantalum, nickel and cobalt have been designed. (author)

  15. Influence of Stockpile Angle in Natural Drying of Laterite Ore

    Directory of Open Access Journals (Sweden)

    Yoalbys Retirado-Mediaceja

    2016-10-01

    Full Text Available Natural drying is performed at Cuban nickel plants by depositing bulk ore in the open. The ore is currently being stockpiled without much consideration for the impact of the drying surface angle on the process power behavior. Simulations were carried out in this investigation, which prove that an increased triangular stockpile angle considerably reduces natural drying efficiency. A 45 sexagesimal degree angle to the horizontal plane results in exposure of a large volume of ore to natural drying and guarantees adequate energy performance.

  16. Water leaching of titanium from ore flotation residue.

    Science.gov (United States)

    Jaworska, Malgorzata M; Guibal, Eric

    2003-01-01

    Copper ore tailings were tested for the stability of titanium submitted to water leaching in three different reactor systems (agitated vessel, bioreactor and percolated fixed-bed column). For each of these systems, titanium extraction did not exceed 1% of the available metal. Biomass removed from ore residue adsorbed a small part of the titanium with sorption capacities below 20-30 mg g(-1), but most of this biomass was sequestered in the ore residue. Oxygen and carbon dioxide concentrations were monitored and changes in concentration correlated with bacteria development at the initial stage of the process and to fungal development in the latter stages.

  17. Biosolubilization of uranyl ions in uranium ores by hydrophyte plants

    International Nuclear Information System (INIS)

    Cecal, Alexandru; Calmoi, Rodica; Melniciuc-Puica, Nicoleta

    2006-01-01

    This paper investigated the bioleaching of uranyl ions from uranium ores, in aqueous medium by hydrophyte plants: Lemna minor, Azolla caroliniana and Elodea canadensis under different experimental conditions. The oxidation of U(IV) to U(VI) species was done by the atomic oxygen generated in the photosynthesis process by the aquatic plants in the solution above uranium ores. Under identical experimental conditions, the capacity of bioleaching of uranium ores decreases according to the following series: Lemna minor > Elodea canadensis > Azolla caroliniana. The results of IR spectra suggest the possible use of Lemna minor and Elodea canadensis as a biological decontaminant of uranium containing wastewaters. (author)

  18. Determination of the oxidizing capacity of manganese ores.

    Science.gov (United States)

    Prasad, R

    1974-09-01

    An accurate method is described for determining the amount of active oxygen in manganese ores, based on the oxidation-reduction reaction between the ore and arsenic(III) in presence of ammonium molybdate, followed by the back-titration of excess of arsenic(III) with cerium(IV), using osmium tetroxide as catalyst and Disulphine Blue V as indicator. A survey has been made of the applicability of this method to various pyrolusite ores containing less than 0.2% phosphorus. Aluminium(III), copper(II), iron(III), manganese(II), and molybdenum(VI) do not interfere. Up to 30% phosphorus(V) causes no interference.

  19. Difference of ore-bearing and non-ore-bearing pegmatite in the Guangshigou area and its research significance

    International Nuclear Information System (INIS)

    Zuo Wenqian; Zhang Zhanshi; Sha Yazhou; Rao Chaojun

    2011-01-01

    Guangshigou uranium deposit is one of the typical granite-pegmatite uranium deposits in China, the ore-body are located in the density zone of the outside contact zone of granite pluton. To distinguish the ore-bearing and Non-ore-bearing pegmatite is one of the most practices and have great significance for the effect of mineral exploration. Based on the field investigation and former research results, contrast research on the characteristics of the pegmatite on petrology, geophysical, geochemistry and stable isotopes have been carried out. It is pointed out that the ore-bearing pegmatite differ from the non-ore-bearing one from macro-and-micro-view in Guangshigou Uranium deposits, the main characteristics are summarized; the macro-and-micro signs are established, the genetic difference between the ore-bearing and non-ore-bearing pegmatite are discussed primarily. The achievements would be helpful for prospecting and researching of this type uranium deposits in China. (authors)

  20. Ore-forming environment and ore-forming system of carbonaceous-siliceous-pelitic rock type uranium deposit in China

    International Nuclear Information System (INIS)

    Qi Fucheng; Zhang Zilong; Li Zhixing; He Zhongbo; Wang Wenquan

    2012-01-01

    It is proposed that there are four types of ore-forming systems about carbonaceous-siliceous-pelitic rock type uranium deposit in China based on systematic study on structural environment and distribution regularity of uraniferous construction of marine carbonaceous-siliceous-pelitic rock in China: continental margin rift valley ore-forming systems, continental margin rifting deep fracture zone ore-forming systems, landmass boundary borderland basin ore-forming systems and epicontinental mobile belt downfaulted aulacogen ore-forming systems. It is propounded definitely that it is controlled by margin rift valley ore-forming systems and continental margin rifting deep fracture zone ore-forming systems for large-scale uranium mineralization of carbonaceous-siliceous-pelitic rock type uranium deposit in China, which is also controlled by uraniferous marine carbonaceous-siliceous-pelitic rock construction made up of silicalite, siliceous phosphorite and carbonaceous-siliceous-pelitic rock, which settled down accompany with submarine backwash and sub marine volcanic eruption in margin rift valley and continental margin rifting mineralizing environment. Continental mar gin rift valley and continental margin rifting thermal sedimentation or exhalation sedimentation is the mechanism of forming large-scale uraniferous marine carbonaceous-siliceous-pelitic rock construction Early Palaeozoic Era in China or large-scale uranium-polymetallic mineralization. (authors)

  1. Determination of Gold from Gold Matrix of North Western Nigeria ...

    African Journals Online (AJOL)

    The research paper presents analytical results of Au, Mn and V concentrations of some Nigerian gold ores using two techniques: epithermal neutron activation analysis (ENAA) and proton induced X-ray emission (PIXE). Fourteen samples were collected from gold fields of North Western Nigeria, prepared separately to a ...

  2. Evolution of mineralizing brines in the east Tennessee Mississippi Valley-type ore field

    Energy Technology Data Exchange (ETDEWEB)

    Kesler, S.E.; Gesink, J.A.; Haynes, F.M. (Univ. of Michingan, Ann Arbor (USA))

    1989-05-01

    The east Tennessee Mississippi Valley-type (MVT) ore field contains barite-fluorite and sphalterite deposits in a continuous paleoaquifer consisting of breccia zones in the Upper Cambrian-Lower Ordovician Knox Group. Paragenetic observations and fluid inclusion compositions in these deposits indicate that the Knox paleoaquifer was invaded first by Ca-rich brines (Ca:Na about 1) that deposited fluorite and barite, and later by Na-Ca brines (Ca:Na = 0.1 to 0.5) that deposited sphalerite. Geologic relation sindicate that these brines were derived from the southeast, in the area of the Middle Ordovician Servier foreland shale basin, and that imposed by fluorite solubility indicate further that all original connate water in the Sevier basin was required to deposit the estimated flourite reserves of the ore field.Thus, the later, sphalerite-depositing brines represent recycled meteoric water from the Sevier basin or connate brines from underlying (Cambrian) shales.

  3. Flotation of zinc and lead oxide minerals from Olkusz region calamine ores

    Directory of Open Access Journals (Sweden)

    Cichy Krystian

    2016-01-01

    Full Text Available The paper presents chemical and mineralogical characteristics of calamine ore from the Pomorzany mine. A flowsheet for recovery of sulphide minerals of zinc and lead in the form of the Zn-Pb bulk concentrate was presented. In the following part, preparation of the feed for flotation of Zn-Pb oxide minerals and optimal conditions for separation from it iron sulphide minerals, represented by marcasite, were determined. In the final section the results of flotation of Zn-Pb oxide minerals with anionic collector AM2 belonging to the hydroxyamide group of collectors and a cationic collector in the form of a coconut amine, being a mixture of primary aliphatic amines, were presented. Basing on the obtained results, a technological flowsheet for the recovery of Zn-Pb sulphide and oxide minerals from the calamine ore of the Pomorzany mine was presented.

  4. Experiment on bio-leaching of associated molybdenum and uranium ore

    International Nuclear Information System (INIS)

    Zheng Ying; Fan Baotuan; Liu Jian; Meng Yunsheng; Liu Chao

    2007-01-01

    Column leaching experiment results on associated molybdenum uranium ore by bacteria (T. f) are introduced. The ore are leached for 210 days using bacteria domesticated to tolerate molybdenum, the leaching of uranium is of 98% and leaching of molybdenum is of 41%. Sulphuric acid produced by bio-oxidation of sulfides in ore can meet the demand of ore leaching. (authors)

  5. 40 CFR 440.40 - Applicability; description of the mercury ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... mercury ore subcategory. 440.40 Section 440.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Mercury Ore Subcategory § 440.40 Applicability; description of the mercury ore subcategory. The provisions of subpart D...

  6. Petrological and geochemical features of the early Paleozoic granitic gneisses and iron ores in the Tianhu iron deposit, Eastern Tianshan, NW China: Implications for ore genesis

    Science.gov (United States)

    Zheng, Jiahao; Mao, Jingwen; Yang, Fuquan; Chai, Fengmei; Shen, Ping

    2017-08-01

    This paper reports whole-rock geochemical, zircon U-Pb and Hf isotopic data for ore-hosted granitic gneisses, mineral compositions of oxides, and sulfur isotopic data for sulfides in iron ores from the Tianhu deposit, central part of the Eastern Tianshan. Our results can provide crucial constraints on the genesis of granitic gneisses and early Paleozoic tectonic setting of the Eastern Tianshan. LA-ICP-MS U-Pb dating on magmatic zircons yielded weighted mean 206Pb/238U ages of 463 to 438 Ma, interpreted as the crystallization ages of the granitic protoliths and the formation ages of the Tianhu Group. Zircon U-Pb age of ore-hosted granitic gneiss (ca. 459 Ma) can provide reliable constrains on upper limit for iron mineralization age in the Tianhu deposit. Geochemical characteristics suggest that the protoliths of the Tianhu granitic gneisses are metaluminous to weakly peraluminous high-K calc-alkaline granitic rocks, exhibiting typical subduction-related features such as strong enrichment in LREE and LILE and depletion in HFSE. Zircon Hf isotopic compositions show a positive trend from 463 to 438 Ma, indicating that 460 Ma magmas came from both ancient and juvenile sources, whereas 438 Ma magmas involved more juvenile material. Some early Paleozoic granitoids were recently identified in the Eastern Tianshan with the ages between ca. 475 and ca. 425 Ma. The formation of these early Paleozoic granitoids was in response to subduction processes, suggesting that subduction of Junggar Ocean probably began in the Early Ordovician and lasted until Late Silurian. Pyrite and pyrrhotite in iron ores have δ34SCDT values from + 4.6 to + 15.7‰, which are consistent with the marine source, but inconsistent with the magmatic source or those involved evaporites in skarn iron deposit. Geological, geochemical, and isotopic data suggest that the Tianhu iron ores were formed by volcano-sedimentary processes in a subduction environment during the early Paleozoic time, and Tianhu is a

  7. Ore loses and dilution of the ore vein no. 4 in the Zletovo mine, Republic of Macedonia

    Directory of Open Access Journals (Sweden)

    Bogatinovski Nikola L.

    2017-01-01

    Full Text Available Zletovo mines have a tradition of exploration and exploitation of vein lead-zinc ores for almost a century. Ore losses and dilutions have always been imperative in production since traditional old methods of mining and low-productivity mineralization are used. In conditions of classical and sub-level method excavations used, the calculated ore losses in ore vein No. 4 are 13.5%, while at the level of all excavations in the Zletovo mines dilution averages at 10%. Ore dilution is also an important technical parameter and several possible variants were calculated. When analyzing the dilution that occurs during the preparation of the sub-level corridor with parameters such: different drop angle (45-60o, constant thickness of 1.47 m as the average vein thickness in the calculated ore reserves, width of the sub-level corridor of 1.57 m or to the width of the ore vein No. 4 were added 10 cm (left and right to 5 cm as much as is taken in the calculation of the planned dilution and height of 2.5 m as suggested for this mining method, it can be noticed that the planned dilution during this method of mining ranges from 26.3% to 42.3%. In conditions of use of this underground method of excavation, parameters are selected that allow for the indicated lowering of the dilution. Namely, the thickness of the ore wire would be 1.47 m, the mining width would be 1.57 m, only 10 cm (left and right up to 5cm to the thickness of the ore vein will be added, the height difference between the consecutive levels would be 7.5 m, dip angle of 45 to 60°, and with the excavation the whole ore vein would be covered in height. On the basis of these parameters, models were prepared in which the ore vein would have a different dip angle, from which the values for the planned ore dilution ranged from 6.7 to 7.8%, which is significantly lower than the average dilution in the Zletovo Mine.

  8. Total Ore Processing Integration and Management

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Gertsch

    2006-05-15

    This report outlines the technical progress achieved for project DE-FC26-03NT41785 (Total Ore Processing Integration and Management) during the period 01 January through 31 March of 2006. (1) Work in Progress: Minntac Mine--Graphical analysis of drill monitor data moved from two-dimensional horizontal patterns to vertical variations in measured and calculated parameters. The rock quality index and the two dimensionless ({pi}) indices developed by Kewen Yin of the University of Minnesota are used by Minntac Mine to design their blasts, but the drill monitor data from any given pattern is obviously not available for the design of that shot. Therefore, the blast results--which are difficult to quantify in a short time--must be back-analyzed for comparison with the drill monitor data to be useful for subsequent blast designs. {pi}{sub 1} indicates the performance of the drill, while {pi}{sub 2} is a measure of the rock resistance to drilling. As would be expected, since a drill tends to perform better in rock that offers little resistance, {pi}{sub 1} and {pi}{sub 2} are strongly inversely correlated; the relationship is a power function rather than simply linear. Low values of each Pi index tend to be quantized, indicating that these two parameters may be most useful above certain minimum magnitudes. (2) Work in Progress: Hibtac Mine--Statistical examination of a data set from Hibtac Mine (Table 1) shows that incorporating information on the size distribution of material feeding from the crusher to the autogenous mills improves the predictive capability of the model somewhat (43% vs. 44% correlation coefficient), but a more important component is production data from preceding days (26% vs. 44% correlation coefficient), determined using exponentially weighted moving average predictive variables. This lag effect likely reflects the long and varied residence times of the different size fragments in the grinding mills. The rock sizes are also correlated with the geologic

  9. XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

    Energy Technology Data Exchange (ETDEWEB)

    Omran, Mamdouh, E-mail: mamdouh.omran@oulu.fi [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); Fabritius, Timo [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A. [Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); El-Aref, Mortada; Elmanawi, Abd El-Hamid [Geology Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2015-08-01

    Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe{sub 2}O{sub 3} and P{sub 2}O{sub 5} contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe{sup 3+}) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases.

  10. Radioanalysis of RE enrichment of ion adsorption type RE ores

    CERN Document Server

    Zhao Shu Quan; Hu He Ping; Li Fu Sheng; Chen Ying Min; LiuShiMing

    2002-01-01

    Objective: To analyze the radioactivity in Rare Earth (RE) enrichment of ion adsorption type RE ores. Methods: Using HPGe-gamma spectrometer to analyze the activity ratio of gamma radionuclides in kind of samples, using FJ-2603 low background alpha, beta measurement apparatus to measure their total alpha and total beta activities, and using X-ray fluorescence spectrometer to analyze contents of La sub 2 O sub 3 and Y sub 2 O sub 3 , respectively. Results: HPGe gamma spectroscopy and X-ray fluorescence spectroscopy are simple, convenient and non-destructive methods of analyzing radionuclides and La sub 2 O sub 3 , Y sub 2 O sub 3 in RE enrichment of ion adsorption type RE ores, respectively. Conclusion: The basic data were provided for radiation protection and treatment of gas, liquid and solid waste in RE production of ion adsorption type RE ores; method and experience were provided for studying ion adsorption type RE ores

  11. Arsenic bioleaching in medical realgar ore and arsenic- bearing ...

    African Journals Online (AJOL)

    Oxidation of these two ores by sulfuric acid was insignificant, as maximum arsenic leaching ratios ... Poor water solubility and weak gastrointestinal absorption of coarse ..... Wu XH, Sun DH, Zhuang ZX, Wang XR, Gong HF, Hong. JX, Lee FSC.

  12. Beneficiation studies of Bajaur manganese ore by different processing techniques

    International Nuclear Information System (INIS)

    Riaz, M.; Khan, F.U.; Yamin, A.; Bilquees, R.; Muhammad, N.

    2010-01-01

    The manganese ore of Bajaur Agency of Pakistan was subjected to flotation, heavy medium separation, gravity concentration and magnetic separation techniques for beneficiation. The original composition of the manganese ore was 45.56% Mn , 4% Fe/sub 2/O/sub 3/, 40% SiO/sub 2/. The Mn content was raised to a maximum 48.76 % in the concentrate with the recovery of 67.78 % through flotation technique. Other techniques rendered marginal increase in Mn concentration against the theoretical possibility of substantial enrichment by rejecting the 20 % gangue minerals. The separation of manganese minerals from associated gangue was difficult, due to mineralogical complexity of the ore, extreme fineness of the particle size, texture and minerals intergrowth. High Mn/Fe ratio, phosphorus, and silica contents were within tolerable limits for utilisation of the ore in ferro-manganese production. (author)

  13. chemical and mineralogical characterization of lateritic iron ore

    African Journals Online (AJOL)

    DJFLEX

    2010-04-22

    Apr 22, 2010 ... The laterite iron ore deposit at Auchi, Edo State, Nigeria was studied chemically and mineralogically. The results of the chemical ... SAMPLE PREPARATION. The samples .... 2µm) and were subjected to X-ray diffraction using.

  14. By lithology Zbruch deposits (Lower Sarmatian Nikopol manganese ore Basin

    Directory of Open Access Journals (Sweden)

    Bogdanovich V.V.

    2010-06-01

    Full Text Available Based on lithologic-paleogeographic study Zbruch layers of Nikopol manganese ore Basin sediments described lithological and genetic types of rocks and facies conditions of formation of deposits.

  15. Predicting the Concentration Characteristics of Itakpe Iron Ore for cut ...

    African Journals Online (AJOL)

    MICHAEL HORSFALL

    ABSTRACT: Concentration characteristics of an ore are very critical to the estimation of cut-off grade of a ... enormous financial cost of laboratory analysis and time required for such .... Arua A.I. (1997) Fundamentals of statistics, Publisher,.

  16. Pulmonary function evaluations of dogs exposed to uranium ore dust

    International Nuclear Information System (INIS)

    Loscutoff, S.M.; Buschbom, R.L.; Palmer, R.F.; Cross, F.T.

    1980-01-01

    Pulmonary function evaluations were conducted on dogs exposed to carnotite uranium ore dust. Significant changes were detected in the slope of the single-breath N 2 washout curve, suggesting an uneven distribution of ventilation

  17. Collective sulphide flotation of the polymetallic molybdenic ore

    International Nuclear Information System (INIS)

    Mazanek, C.; Maselko, J.; Rycerz, L.

    1980-01-01

    Results of investigations on polymetallic molybdenic ore are presented. The useful minerals of this ore are as follows: molybdenite, sphalerite, galena and chalcopyrite whereas quartz, feldspars, chlorite and sericite are barren rocks. The flotation process parameters are established i.e. the consumption of flotation reagents, the flotation time and the most advantageous grain composition of the ore submitted to flotation. Taking into consideration the established parameters, a collective sulphide flotation of ore and a control flotation of wastes were carried out. The obtained concentrate was submitted to a single cleaning flotation whereby a concentrate was obtained containing: 4,65% Mo, 2,51% Cu, 0,9% Zn, 0,69% Pb, and 1,4% Bi. (author)

  18. Comparison of oxidants in alkaline leaching of uranium ore

    International Nuclear Information System (INIS)

    Sreenivas, T.; Rajan, K.C.; Srinivas, K.; Anand Rao, K.; Manmadha Rao, M.; Venkatakrishnan, R.R.; Padmanabhan, N.P.H.

    2007-01-01

    The uranium minerals occurring in various ore deposits consists of predominantly uranous ion (U +4 ), necessitating use of an oxidant and other lixiviants for efficient dissolution during leaching. Unlike acid leaching route, where uranium minerals dissolution could be achieved efficiently with cheaper lixiviants, processing of ores by alkaline leaching route involve expensive lixiviants and drastic leaching conditions. Alkaline leaching of uranium ores becomes economical only upon using cheaper and efficient oxidants and conservation of other reagents by their recycle. The present paper gives efficacy of various oxidants - KMnO 4 , NaOCl, Cu - NH 3 , air and oxygen, in the leaching of uranium from a low-grade dolostone hosted uranium ore of India. A comparison based on technical merits and cost of the oxidant chemicals is discussed. (author)

  19. Mössbauer Spectral Data of Vermiculite Ore

    Data.gov (United States)

    Department of the Interior — Data are provide for four samples of unexpanded vermiculite ore from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, and South Africa....

  20. Iron isotope fractionation during hydrothermal ore deposition and alteration

    Science.gov (United States)

    Markl, Gregor; von Blanckenburg, Friedhelm; Wagner, Thomas

    2006-06-01

    Iron isotopes fractionate during hydrothermal processes. Therefore, the Fe isotope composition of ore-forming minerals characterizes either iron sources or fluid histories. The former potentially serves to distinguish between sedimentary, magmatic or metamorphic iron sources, and the latter allows the reconstruction of precipitation and redox processes. These processes take place during ore formation or alteration. The aim of this contribution is to investigate the suitability of this new isotope method as a probe of ore-related processes. For this purpose 51 samples of iron ores and iron mineral separates from the Schwarzwald region, southwest Germany, were analyzed for their iron isotope composition using multicollector ICP-MS. Further, the ore-forming and ore-altering processes were quantitatively modeled using reaction path calculations. The Schwarzwald mining district hosts mineralizations that formed discontinuously over almost 300 Ma of hydrothermal activity. Primary hematite, siderite and sulfides formed from mixing of meteoric fluids with deeper crustal brines. Later, these minerals were partly dissolved and oxidized, and secondary hematite, goethite and iron arsenates were precipitated. Two types of alteration products formed: (1) primary and high-temperature secondary Fe minerals formed between 120 and 300 °C, and (2) low-temperature secondary Fe minerals formed under supergene conditions (illustrates the potential of the new technique in deciphering ore formation and alteration processes. Isotope ratios are strongly dependent on and highly characteristic of fluid and precipitation histories. Therefore, they are less suitable to provide information on Fe sources. However, it will be possible to unravel the physico-chemical processes leading to the formation, dissolution and redeposition of ores in great detail.

  1. A finite difference model of the iron ore sinter process

    OpenAIRE

    Muller, J.; de Vries, T.L.; Dippenaar, B.A.; Vreugdenburg, J.C.

    2015-01-01

    Iron ore fines are agglomerated to produce sinter, which is an important feed material for blast furnaces worldwide. A model of the iron ore sintering process has been developed with the objective of being representative of the sinter pot test, the standard laboratory process in which the behaviour of specific sinter feed mixtures is evaluated. The model aims to predict sinter quality, including chemical quality and physical strength, as well as key sinter process performance parameters such ...

  2. Uranium mobilization from low-grade ore by cyanobacteria

    International Nuclear Information System (INIS)

    Lorenz, M.G.; Krumbein, W.E.

    1985-01-01

    Three cyanobacterial isolates (two LPP-B forms and one Anabaena or Nostoc species) from different environments could mobilize uranium from low-grade ores. After 80 days, up to 18% uranium had been extracted from coal and 51% from a carbonate rock by the filamentous cyanobacterium OL3, a LPP-B form. Low growth requirements with regard to light and temperature optima make this strain a possible candidate for leaching neutral and alkaline low-grade uranium ores. (orig.)

  3. Uranium mobilization from low-grade ore by cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, M.G.; Krumbein, W.E.

    1985-04-01

    Three cyanobacterial isolates (two LPP-B forms and one Anabaena or Nostoc species) from different environments could mobilize uranium from low-grade ores. After 80 days, up to 18% uranium had been extracted from coal and 51% from a carbonate rock by the filamentous cyanobacterium OL3, a LPP-B form. Low growth requirements with regard to light and temperature optima make this strain a possible candidate for leaching neutral and alkaline low-grade uranium ores.

  4. NRC's limit on intake of uranium-ore dust

    International Nuclear Information System (INIS)

    McGuire, S.A.

    1983-04-01

    In 1960 the Atomic Energy Commission adopted an interim limit on the intake by inhalation of airborne uranium-ore dust. This report culminates two decades of research aimed at establishing the adequacy of that limit. The report concludes that the AEC underestimated the time that thorium-230, a constituent of uranium-ore dust, would remain in the human lung. The AEC assumed that thorium-230 in ore dust would behave like uranium with a 120-day biological half-life in the lung. This report concludes that the biological half-life is actually on the order of 1 year. Correcting the AEC's underestimate would cause a reduction in the permitted airborne concentration of uranium-ore dust. However, another factor that cancels the need for that reduction was found. The uranium ore dust in uranium mills was found to occur with very large particle sizes (10-micron activity median aerodynamic diameter). The particles are so large that relatively few of them are deposited in the pulmonary region of the lung, where they would be subject to long-term retention. Instead they are trapped in the upper regions of the respiratory tract, subsequently swallowed, and then rapidly excreted from the body through the gastrointestinal tract. The two effects are of about the same magnitude but in opposing directions. Thus the present uranium-ore dust intake limit in NRC regulations should provide a level of protection consistent with that provided for other airborne radioactive materials. The report recalculates the limit on intake of uranium-ore dust using the derived air concentrations (DAC) from the International Commission on Radiological Protection's recent Publication 30. The report concludes that the silica contained in uranium-ore dust is a greater hazard to workers than the radiological hazard

  5. Methods for the estimation of uranium ore reserves

    International Nuclear Information System (INIS)

    1985-01-01

    The Manual is designed mainly to provide assistance in uranium ore reserve estimation methods to mining engineers and geologists with limited experience in estimating reserves, especially to those working in developing countries. This Manual deals with the general principles of evaluation of metalliferous deposits but also takes into account the radioactivity of uranium ores. The methods presented have been generally accepted in the international uranium industry

  6. Radiotracer investigations of the flotation process in copper ore processing

    International Nuclear Information System (INIS)

    Petryka, L.; Przewlocki, K.

    1983-01-01

    Optimization of copper ore processing requires in particular the investigation of the flotation process. 64 Cu induced in natural ore by activation was used as a tracer. Detailed measurements were performed in an industrial flotation plant consisting of 14 cells. As a result the mean residence time of different grain size fractions of natural copper sulphide was determined for all parts of the flotation plant together with the efficiency of the flotation process. (author)

  7. Assessment of the contrast of rare metal ores

    International Nuclear Information System (INIS)

    Kuznetsova, O.V.

    1987-01-01

    The method of rapid assessment of useful component content on the basis of X-ray radiometric method of analysis of non-crushed ore lumps is presented. Using as an example rare metal deposits, linear dependence between logarithms of Nb 2 O 6 contents and the value of fragment separation index during radiometric separation is established. The use of the dependence ensures sufficient accuracy for the characteristic of rare metal ore content

  8. Extraction of lithium Carbonate from Petalite Ore (Momeik District, Myanmar)

    International Nuclear Information System (INIS)

    Tun Tun Moe

    2011-12-01

    The methods for preparing high purity lithium carbonate which can be used for pharmaceutical applications, electronic grade crystals of lithium or to prepare battery-grade lithium metal are disclosed. Lithium carbonate as commercially produced from mineral extraction, lithium containing brines or sea water. One method for the production of pure lithium carbonate from mineral source (petalite ore) obtained from Momeik District, Myanmar is disclosed. Method for mineral processing of ore concentrate is also disclosed.

  9. Rare earth mobility in hydrothermal ore-forming systems

    International Nuclear Information System (INIS)

    Cornell, D.H.; Schade, J.; Scheepers, R.; Watkeys, M.K.

    1988-01-01

    Rocks and ores which form by magmatic processes display a range of chondrite-normalised rare earth profiles. One REE (rare earth elements) profile feature which seems unrelated to magmatic processes is the birdwing profile, in which both heavy and light rare earths are enriched relative to the middle rare earths. Birdwing rare earth profiles are an easily identified geochemical anomaly. It is proposed that rare earth geochemistry could be applied in geochemical prospecting for ore formed by hydrothermal processes. 5 figs

  10. Radioisotopes investigations of copper ore dressing processes

    International Nuclear Information System (INIS)

    Petryka, L.; Furman, L.; Przewlocki, K.; Stegowski, Z.

    1992-01-01

    This paper describes radioisotope applications in the copper industry, mainly for the examination of comminution, classification, and flotation processes for selected physical parameters. Measurements were performed by a mobile laboratory containing the electronics for experiment control and data recording and processing using special computer software. This system makes it possible to determine measurements in an industrial environment. The data acquisition system provides 24 spectrometric channels, consisting of scintillation probes, high-voltage (HV) power supplies, and pulse-height analyzers, as well as an analog-to-digital (A/D) converter interfaced to the IBM personal computer. The sampling time is fully programmable and interrupt based and can vary from 1 ms to hours and may be set separately for each channel. The milli-second sampling time technique has been applied to high-resolution flow velocity measurements. On the other hand, longer sampling time enables the system to be left unattended for days to monitor, for example, copper ore concentration or efficiency of the flotation process

  11. Flotation of uranium from uranium ores in Canada. Part 1

    International Nuclear Information System (INIS)

    Muthuswami, S.V.; Vigayan, S.; Woods, D.R.; Banerjee, S.

    1983-01-01

    About 150 flotation tests were done on Elliot Lake ore with 15 reagents as collectors in order to screen and choose an attractive collector for uranium flotation. Several variables were studied including pH, conditioning time and mode of collector addition. The tests were done in a Denver or Agitair subaeration cell. The particle size of the ore was kept at 85% below -325 mesh. Three reagents (Kelex 00, TOPO, and cupferron) were identified as having the most promise. The best results were obtained with cupferron, where 93-95% of the uranium was recovered in 25-30% of the mass of original ore. Radium in the tails varied between 5 and 30 pCi/g depending on the mass of uranium floated. Radium was recovered in proportion to uranium in the tests done at neutral pH. The preconcentration results obtained by flotation alone were comparable to those obtained using pyrite flotation and wet high-intensity magnetic separation of uranium. The consumption of cupferron was 4 kg/Mg ore for each flotation stage. This was 10-15 times larger than the collector usage in conventional oxide flotation. This scheme did not require other reagents as depressants, activators or modifiers. Reproducibility was good and similar recoveries were obtained with fresh or old ores, and with distilled or mine water. The selectivity of cupferron for uranium in the ore studied was outstanding

  12. Uranium and thorium recovery in thorianite ore-preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Gaiotte, Joao V.M. [Universidade Federal de Alfenas, Pocos de Caldas, MG (Brazil); Villegas, Raul A.S.; Fukuma, Henrique T., E-mail: rvillegas@cnen.gov.br, E-mail: htfukuma@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Pocos de Caldas, MG (Brazil). Lab. de Pocos de Caldas

    2011-07-01

    This work presents the preliminary results of the studies aiming to develop a hydrometallurgical process to produce uranium and thorium concentrates from thorianite ore from Amapa State, Brazil. This process comprises two major parts: acid leaching and Th/U recovery using solvent extraction strategies. Thorianite ore has a typical composition of 60 - 70% of thorium, 8 - 10% lead and 7 - 10% uranium. Sulfuric acid leaching operational conditions were defined as follows: acid/ore ratio 7.5 t/t, ore size below 65 mesh (Tyler), 2 hours leaching time and temperature of 100 deg C. Leaching tests results showed that uranium and thorium recovery exceeded 95%, whereas 97% of lead ore content remained in the solid form. Uranium and thorium simultaneous solvent extraction is necessary due to high sulfate concentration in the liquor obtained from leaching, so the Primene JM-T primary anime was used for this extraction step. Aqueous raffinate from extraction containing sulfuric acid was recycled to the leaching step, reducing acid uptake around 60%, to achieve a net sulfuric acid consumption of 3 t/t of ore. Uranium and thorium simultaneous stripping was performed using sodium carbonate solution. In the aqueous stripped it was added sulfuric acid at pH 1.5, followed by a second solvent extraction step using the tertiary amine Alamine 336. The following stripping step was done with a solution of sodium chloride, resulting in a final solution of 23 g L-1 uranium. (author)

  13. Breakaway frictions of dynamic O-rings in mechanical seals

    Science.gov (United States)

    Lai, Tom; Kay, Peter

    1993-05-01

    Breakaway friction of a dynamic O-ring affects the mechanical seal's response to large axial shaft movement and face wear. However, little data exist to help designers. Therefore, a test rig was developed to measure breakaway friction. The research quantitatively shows the effects of lubrication with silicone grease and a change of surface finish. By using the Taguchi statistical experimental design method, the significance of test parameters was evaluated with a minimum number of tests. It was found that fluid pressure, dwell time, and O-ring percentage squeeze affect O-ring breakaway friction more than the O-ring cross sectional diameter and axial sliding speed within the range of values tested. The authors showed that breakaway friction increased linearly with pressure. However, O-rings made of different materials had significantly different increase rates, even if they had nominally the same durometer hardness. Breakaway friction also increased with logarithm of dwell time. Again, the increase rate depended strongly on the specific O-ring material tested. These observations led the authors to believe that the typical approach of generalizing data based on generic polymer type and durometer was inappropriate.

  14. Potential for cobalt recovery from lateritic ores in Europe

    Science.gov (United States)

    Herrington, R.

    2012-04-01

    Cobalt is one of the 'critical metals' identified under the EU Raw Materials Initiative. Annually the global mine production of cobalt is around 55,000 tonnes,with Europe's industries consuming around 30% of that figure. Currently Europe produces around 27 tonnes of cobalt from mines in Finland although new capacity is planned. Co-bearing nickel laterite ores being mined in Greece, Macedonia and Kosovo where the cobalt is currently not being recovered (ores have typical analyses of 0.055% Co and >1% Ni,). These ores are currently treated directly in pyrometallurgical plants to recover the contained nickel and this process means there is no separate cobalt product produced. Hydrometallurgical treatment of mineralogically suitable laterite ores can recover the cobalt; for example Cuba recovers 3,500 tonnes of cobalt from its laterite mining operations, which are of a similar scale to the current European operations. Implementation of hydrometallurgical techniques is in its infancy in Europe with one deposit in Turkey planning to use atmospheric heap leaching to recover nickel and copper from oxide-dominated ores. More widespread implementation of these methods to mineralogically suitable ore types could unlock the highly significant undeveloped resources (with metal contents >0.04% Co and >1% Ni), which have been defined throughout the Balkans eastwards into Turkey. At a conservative estimate, this region has the potential to supply up to 30% of the EU cobalt requirements.

  15. Automated microscopic characterization of metallic ores with image analysis: a key to improve ore processing. I: test of the methodology

    International Nuclear Information System (INIS)

    Berrezueta, E.; Castroviejo, R.

    2007-01-01

    Ore microscopy has traditionally been an important support to control ore processing, but the volume of present day processes is beyond the reach of human operators. Automation is therefore compulsory, but its development through digital image analysis, DIA, is limited by various problems, such as the similarity in reflectance values of some important ores, their anisotropism, and the performance of instruments and methods. The results presented show that automated identification and quantification by DIA are possible through multiband (RGB) determinations with a research 3CCD video camera on reflected light microscope. These results were obtained by systematic measurement of selected ores accounting for most of the industrial applications. Polarized light is avoided, so the effects of anisotropism can be neglected. Quality control at various stages and statistical analysis are important, as is the application of complementary criteria (e.g. metallogenetic). The sequential methodology is described and shown through practical examples. (Author)

  16. Automated microscopic characterization of metallic ores with image analysis: a key to improve ore processing. II: metallogenetic discriminating criteria

    International Nuclear Information System (INIS)

    Castroviejo, R.; Berrezueta, E.

    2009-01-01

    ore microscopy may furnish very important information for geo metallurgists, but todays needs for automation are difficult to meet with the optical microscope unless and adequate methodology is developed. Some limitations of the routine procedure, related to risks of mis identification caused by the spectral similarity of some ores, ask for complementary criteria. Defining ore deposit typologies and the corresponding assemblages guides the choice of species and limits the number. Comparison of the reflectance values of the ores in each mineral association defined shows that their automated identification is possible in most of the common occurrence. The number of species to be actually considered being greatly limited, performance is increased. The system is not intended to substitute for a mineralogist, but to enhance enormously his performance, while offering the industry an economic procedure to procedure a wealth of information which would not be possible with traditional methods, as the point counter. (Author) 33 refs.

  17. Associations between cigarette smoking status and colon cancer prognosis among participants in North Central Cancer Treatment Group Phase III Trial N0147.

    Science.gov (United States)

    Phipps, Amanda I; Shi, Qian; Newcomb, Polly A; Nelson, Garth D; Sargent, Daniel J; Alberts, Steven R; Limburg, Paul J

    2013-06-01

    By using data from North Central Cancer Treatment Group Phase III Trial N0147, a randomized adjuvant trial of patients with stage III colon cancer, we assessed the relationship between smoking and cancer outcomes, disease-free survival (DFS), and time to recurrence (TTR), accounting for heterogeneity by patient and tumor characteristics. PATIENTS AND METHODS Before random assignment to infusional fluorouracil, leucovorin, and oxaliplatin (FOLFOX) or FOLFOX plus cetuximab, 1,968 participants completed a questionnaire on smoking history and other risk factors. Cox models assessed the association between smoking history and the primary trial outcome of DFS (ie, time to recurrence or death), as well as TTR, adjusting for other clinical and patient factors. The median follow-up was 3.5 years among patients who did not experience events. Compared with never-smokers, ever smokers experienced significantly shorter DFS (3-year DFS proportion: 70% v 74%; hazard ratio [HR], 1.21; 95% CI, 1.02 to 1.42). This association persisted after multivariate adjustment (HR, 1.23; 95% CI, 1.02 to 1.49). There was significant interaction in this association by BRAF mutation status (P = .03): smoking was associated with shorter DFS in patients with BRAF wild-type (HR, 1.36; 95% CI, 1.11 to 1.66) but not BRAF mutated (HR, 0.80; 95% CI, 0.50 to 1.29) colon cancer. Smoking was more strongly associated with poorer DFS in those with KRAS mutated versus KRAS wild-type colon cancer (HR, 1.50 [95% CI, 1.12 to 2.00] v HR, 1.09 [95% CI, 0.85 to 1.39]), although interaction by KRAS mutation status was not statistically significant (P = .07). Associations were comparable in analyses of TTR. Overall, smoking was significantly associated with shorter DFS and TTR in patients with colon cancer. These adverse relationships were most evident in patients with BRAF wild-type or KRAS mutated colon cancer.

  18. Rb-Sr dating of sphalerites from Mississippi Valley-type (MVT) ore deposits

    Energy Technology Data Exchange (ETDEWEB)

    Nakai, S.; Halliday, A.N.; Kesler, S.E.; Jones, H.D. (Univ. of Michigan, Ann Arbor (United States)); Kyle, J.R. (Univ. of Texas, Austin (United States)); Lane, T.E. (Memorial Univ. of Newfoundland, St. John' s (Canada))

    1993-01-01

    Mississippi Valley-type (MVT) ore deposits are epigenetic carbonate-hosted Pb-Zn deposits that contain galena, sphalerite, fluorite, barite, dolomite, calcite, and quartz. Although they are thought to form from basinal brines, their exact origins are still unclear, partly because of the scarcity of reliable geochronological data. Rb-Sr dating of sphalerites has recently been shown to be a promising technique for the direct dating of ore minerals in MVT deposits. This paper reports the results of a reconnaissance study of sphalerites, their fluid inclusions, and associated minerals from MVT deposits of North America. Sphalerites from Immel mine, Mascot-Jefferson City district, east Tennessee, define a Rb-Sr age of 347 [plus minus] 20 Ma consistent with a Rb-Sr age of 377 [plus minus] 29 Ma for sphalerites from Coy mine in the same district, but inconsistent with models that ascribe their genesis to the effects of the late Paleozoic Alleghenian orogeny. Rb-Sr isotopic analyses of K-feldspar from Immel mine preclude the possibility that the Rb-Sr data reflect feldspar inclusions. Sphalerites from the main ore zone of Daniel's Harbour mine, Newfoundland, do not form a linear isochron and open behavior of the Rb-Sr system is suspected. Sphalerites from the Pine Point district, Northwest Territories, Canada, define a Rb-Sr age of 361 [plus minus] 13 Ma, indicating that the mineralization took place shortly after the deposition of the middle Devonian host carbonate rocks. These results are not compatible with mineralization models based on regional fluid migration related to early Tertiary Cordilleran deformation. Sphalerites from northern Arkansas have very low Rb and Sr concentrations (less than 0.1 ppm). The Rb-Sr data do not form isochrons and the sphalerites have higher [sup 87]Sr/[sup 86]Sr ratios than expected, given their Rb/Sr ratios and reasonable constraints on their ages. 58 refs., 7 figs., 2 tabs.

  19. Biogenic non-crystalline U(IV) revealed as major component in uranium ore deposits

    Science.gov (United States)

    Bhattacharyya, Amrita; Campbell, Kate M.; Kelly, Shelly D.; Roebbert, Yvonne; Weyer, Stefan; Bernier-Latmani, Rizlan; Borch, Thomas

    2017-06-01

    Historically, it is believed that crystalline uraninite, produced via the abiotic reduction of hexavalent uranium (U(VI)) is the dominant reduced U species formed in low-temperature uranium roll-front ore deposits. Here we show that non-crystalline U(IV) generated through biologically mediated U(VI) reduction is the predominant U(IV) species in an undisturbed U roll-front ore deposit in Wyoming, USA. Characterization of U species revealed that the majority (~58-89%) of U is bound as U(IV) to C-containing organic functional groups or inorganic carbonate, while uraninite and U(VI) represent only minor components. The uranium deposit exhibited mostly 238U-enriched isotope signatures, consistent with largely biotic reduction of U(VI) to U(IV). This finding implies that biogenic processes are more important to uranium ore genesis than previously understood. The predominance of a relatively labile form of U(IV) also provides an opportunity for a more economical and environmentally benign mining process, as well as the design of more effective post-mining restoration strategies and human health-risk assessment.

  20. Some developments in the extraction of gold from Witwatersrand ores

    International Nuclear Information System (INIS)

    Laxen, P.A.

    1975-01-01

    The extraction of gold from most ores of the Witwatersrand has been consistently high - approximately 95 per cent - for many years. The present high price of gold has stimulated research and development into potential improvements of the standard procedures. The occurrence of the gold and its association with other minerals is described briefly. The Witwatersrand reefs also contain uranium and pyrite, and some of the improvements to the standard gold-extraction process are associated with the recovery or concentration of one or both of these valuable constituents. For instance, the 'reverse-leach' process, in which acid treatment for the extraction of uranium precedes cyanidation, results in improved gold extraction. Some concentration techniques used on the present residues from cyanidation offer promise in improving the overall gold recoveries. Thucholite is an important carrier of residual gold, and its recovery from some residues by flotation appears to be economically justifiable. Wet high-intensity magnetic separation has given promising results, in the laboratory and on the pilot plant, for the recovery of both uranium and gold from a number of cyanide tailings. The benefits of gravity concentration and of the application of empirical modelling to the gold-extraction process have been demonstrated by a mining group. Some developments in instrumentation for control during cyanidation are discussed briefly [af

  1. Results of the radiological survey at the former ore storage site, Palmerton, Pennsylvania (PP001)

    International Nuclear Information System (INIS)

    Cottrell, W.D.; Quillen, J.L.; Crutcher, J.W.

    1990-12-01

    As part of the Formerly Utilized Sites Remedial Action Program (FUSRAP), the US Department of Energy (DOE) is implementing a radiological survey program to determine the radiological conditions at sites that were used by the department's predecessor agencies. The radiological survey discussed in this report for the former ore storage site in Palmerton, Pennsylvania, is part of the FUSRAP effort and was conducted at the request of DOE by members of the Measurement Applications and Development group of Oak Ridge National Laboratory (ORNL) in 1988. In 1953 and 1954 the Atomic Energy Commission (AEC) established an ore stockpile on the property of the New Jersey Zinc Corporation in Palmerton, Pennsylvania. Approximately 57 truckloads of ore (about 360 tons) were stored at this site and remained there until 1973, when the AEC initiated a clean-up program. The 1988 ORNL radiological survey included a gamma scan at the ground surface, gamma measurements at discrete locations at the surface and at 1 m above the surface, gamma logging of 80 auger holes, and collection of 161 surface and subsurface soil samples. Of these 161 soil samples, 98% were below DOE guidelines for 226 Ra concentration in soil. Interpretation of the data suggests small, isolated spots of residual ore. The data indicate that it is highly unlikely that an individual living or working on this site could receive a radiation dose approaching the 100 mrem annual limit. However, it is suggested that DOE evaluate potential exposures at this site to ensure compliance with their policy that all exposures to radiation are reduced to levels that are as low as reasonably achievable. 4 refs., 88 figs., 4 tabs

  2. Members of the Gammarus pulex-group (Crustacea – Amphipoda) from North Africa and Spain, with description of a new species from Morocco

    NARCIS (Netherlands)

    Pinkster, Sjouk

    1971-01-01

    Gammarus gauthieri (Karaman) was known from North Africa only. During systematic sampling, carried out in 1969 to 1970, it became clear, that the species is also widely distributed in the Iberian peninsula. Comparative descriptions of this species and of two other members of the Gammarus

  3. Status report from South Africa [Processing of Low-Grade Uranium Ores

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, R E [Atomic Energy Board, Pretoria (South Africa)

    1967-06-15

    Most of the research work on the processing of uranium ores in South Africa is being conducted by the Extraction Metallurgy Division of the S.A. Atomic Energy Board. Nevertheless, a considerable amount of applied research has been done by the different mining groups concerned with the operation of uranium plants, and also by the Transvaal and Orange Free State Chamber of Mines research laboratories. There is, however, very close collaboration between the various research groups and the Atomic Energy Board and the main research described is conducted on a collaborative basis.

  4. Hydrochemical uranium mining at the Straz ore deposit and its hydrogeological consequences

    International Nuclear Information System (INIS)

    Hanzlik, J.; Moravec, J.; Macak, P.

    1992-01-01

    The uranium ore deposit at Straz is situated in the North Bohemian Cretaceous Massif. Uranium is extracted from the deposit by underground chemical leaching by means of drills from the ground. Relevant to this kind of extraction, from the hydrogeological and environmental aspects, are the hydrogeological location of the deposit, the kind and amounts of the leaching solution and ways of its injection. The following amounts, in thousand tons, have been injected underground throughout the entire period of practicing chemical extraction of uranium (till 1990): sulfuric acid 3700, nitric acid 270, ammonia 100, hydrofluoric acid 25. The overall area of the leaching fields is 630 hectares, which accommodate 9300 technological boreholes. The environmental burden of the Cenomanian rocks and Turonian water reservoir was analyzed, and significantly elevated heavy metal contents from the recirculation of the technological solutions were found. The solutions expand beyond the leaching fields, causing a contamination of underground water within wider surroundings. The volume of contaminated water in the Turonian reservoir is currently estimated at 2 - 20 million m 3 . Uranium extraction by leaching is harmful at this deposit, having far-reaching impacts on the hydrosphere and ecosystem (increased dust, deforestation of slopes of the Ralsko hill, contamination of water and soil, etc.). Abandoning the ore extraction appears to be the sole feasible approach to this problem. (Z.S.). 2 tabs., 3 figs

  5. The geological characteristics and forming conditions of granite type uranium-rich ore deposits

    International Nuclear Information System (INIS)

    Li Tiangang; Tong Hangshou; Feng Mingyue; Li Yuexiang; Xu Zhan

    1993-03-01

    The forming conditions and concentration mechanism of rich ore, criteria of ore prospecting and selection of uranium-rich ore target area are introduced in the article that is based on the studying of geological characteristics and conditions of granite type uranium-rich ore deposits of No 201 and 361 and on the comparisons of rich and poor ore deposits in geological conditions. Some new view points are also presented as the separate deposition of uranium minerals and gangue minerals is the main mechanism to form rich ore, for rich ore formation the ore enrichment by superimposition is not a universal regularity and most uranium-rich ore deposits are formed within one mineralization stage or mainly in one mineralization stage

  6. The geological characteristics and forming conditions of granite type uranium-rich ore deposits

    Energy Technology Data Exchange (ETDEWEB)

    Tiangang, Li; Hangshou, Tong; Mingyue, Feng; Yuexiang, Li; Zhan, Xu [Beijing Research Inst. of Uranium Geology (China)

    1993-03-01

    The forming conditions and concentration mechanism of rich ore, criteria of ore prospecting and selection of uranium-rich ore target area are introduced in the article that is based on the studying of geological characteristics and conditions of granite type uranium-rich ore deposits of No 201 and 361 and on the comparisons of rich and poor ore deposits in geological conditions. Some new view points are also presented as the separate deposition of uranium minerals and gangue minerals is the main mechanism to form rich ore, for rich ore formation the ore enrichment by superimposition is not a universal regularity and most uranium-rich ore deposits are formed within one mineralization stage or mainly in one mineralization stage.

  7. The mossy north

    DEFF Research Database (Denmark)

    Mateo, Ruben G.; Broennimann, Olivier; Normand, Signe

    2016-01-01

    , as predicted by theory, and whether the assembly mechanisms differ among taxonomic groups. SR increases towards the south in spermatophytes, but towards the north in ferns and bryophytes. SR patterns in spermatophytes are consistent with their patterns of beta diversity, with high levels of nestedness...... and turnover in the north and in the south, respectively, indicating species exclusion towards the north and increased opportunities for speciation in the south. Liverworts exhibit the highest levels of nestedness, suggesting that they represent the most sensitive group to the impact of past climate change...

  8. Radiation background and the incidence of cataracta among the population groups of the Far North. [Radioisotopes: sup(210)Pb; sup(210)Po; sup(137)Cs; sup(90)Sr

    Energy Technology Data Exchange (ETDEWEB)

    Nizhnikov, A I; Miretskij, G I; Ramzaev, P V; Troitskaya, M N [Nauchno-Issledovatel' skij Inst. Radiatsionnoj Gigieny, Leningrad (USSR)

    1984-07-01

    The incidence of senile cataracta in the residents of the Far North regions and the newcomers differing in the effective equivalent dose due to all types of radiation (except radon decay products for lungs) approximately by 2 times, is studied. The data on the age and sex composition of population with initially established diagnosis of senile cataracta are presented. Lens injury is found to occur earlier in men than in women (the difference is about 5 years). Cataracta frequency increases with age. In the native population of the Far North at 65 and older, cataracta takes place by 2-3 times oftener. Investigations are continued to specify the role of the radiation factor in the integrated effect of the environment on the formation of cataracta in population.

  9. Manual on laboratory testing for uranium ore processing

    International Nuclear Information System (INIS)

    1990-01-01

    Laboratory testing of uranium ores is an essential step in the economic evaluation of uranium occurrences and in the development of a project for the production of uranium concentrates. Although these tests represent only a small proportion of the total cost of a project, their proper planning, execution and interpretation are of crucial importance. The main purposes of this manual are to discuss the objectives of metallurgical laboratory ore testing, to show the specific role of these tests in the development of a project, and to provide practical instructions for performing the tests and for interpreting their results. Guidelines on the design of a metallurgical laboratory, on the equipment required to perform the tests and on laboratory safety are also given. This manual is part of a series of Technical Reports on uranium ore processing being prepared by the IAEA's Division of Nuclear Fuel Cycle and Waste Management. A report on the Significance of Mineralogy in the Development of Flowsheets for Processing Uranium Ores (Technical Reports Series No. 196, 1980) and an instruction manual on Methods for the Estimation of Uranium Ore Reserves (No. 255, 1985) have already been published. 17 refs, 40 figs, 17 tabs

  10. Microbial Beneficiation of Salem Iron Ore Using Penicillium purpurogenum

    Science.gov (United States)

    Mishra, M.; Pradhan, M.; Sukla, L. B.; Mishra, B. K.

    2011-02-01

    High alumina and silica content in the iron ore affects coke rate, reducibility, and productivity in a blast furnace. Iron ore is being beneficiated all around the world to meet the quality requirement of iron and steel industries. Choosing a beneficiation treatment depends on the nature of the gangue present and its association with the ore structure. The advanced physicochemical methods used for the beneficiation of iron ore are generally unfriendly to the environment. Biobeneficiation is considered to be ecofriendly, promising, and revolutionary solutions to these problems. A characterization study of Salem iron ore indicates that the major iron-bearing minerals are hematite, magnetite, and goethite. Samples on average contains (pct) Fe2O3-84.40, Fe (total)-59.02, Al2O3-7.18, and SiO2-7.53. Penicillium purpurogenum (MTCC 7356) was used for the experiment . It removed 35.22 pct alumina and 39.41 pct silica in 30 days in a shake flask at 10 pct pulp density, 308 K (35 °C), and 150 rpm. In a bioreactor experiment at 2 kg scale using the same organism, it removed 23.33 pct alumina and 30.54 pct silica in 30 days at 300 rpm agitation and 2 to 3 l/min aeration. Alumina and silica dissolution follow the shrinking core model for both shake flask and bioreactor experiments.

  11. Utilisation of iron ore tailings as aggregates in concrete

    Directory of Open Access Journals (Sweden)

    Francis Atta Kuranchie

    2015-12-01

    Full Text Available Sustainable handling of iron ore tailings is of prime concern to all stakeholders who are into iron ore mining. This study seeks to add value to the tailings by utilising them as a replacement for aggregates in concrete. A concrete mix of grade 40 MPa was prepared in the laboratory with water–cement ratio of 0.5. The concrete were cured for 1, 2, 3, 7, 14 and 28 days. The properties of the concrete such as workability, durability, density, compressive strength and indirect tensile strength were tested. A controlled mix of concrete was also prepared in similar way using conventional materials and the results were compared with the tailings concrete. It was found that the iron ore tailings may be utilised for complete replacement for conventional aggregates in concrete. The iron ore tailings aggregates concrete exhibited a good mechanical strength and even in the case of compressive strength, there was an improvement of 11.56% over conventional aggregates concrete. The indirect tensile strength did not improve against the control mix due high content of fines in the tailings aggregates but showed 4.8% improvement compared with the previous study where the conventional fine aggregates was partially replaced by 20% with iron ore tailings.

  12. Acid curing and baking of bastnasite ore and concentrate

    International Nuclear Information System (INIS)

    Topkaya, Y.; Akkurt, S.

    1998-01-01

    Full text: In this study, the hydrometallurgical evaluation of a rare earth ore as well as a concentrate obtained from this was done at laboratory. For the mentioned study, a bastnasite type rare earth ore located in Beylikahir in Turkey was used. The total rare earth oxide (REO) content of the deposit was estimated to be 1 million tons with an average concentration of 3.42%REO. The rare earths were contained in bastnasite mineral. The other constituents of the ore were calcium fluoride (52.5%), barite (25.4%), calcite (2.8%) and minor amounts of thorium, iron, manganese, etc. The bastnasite mineral occurred either as cement material between fluoride and barite particles or as intimately associated with these minerals. The rare earth elements were enriched considerably in sub-sieve sizes. After extensive research about the physical concentration of this ore, two different metallurgical routes were followed for the extraction of REE from the ore itself or the preconcentrate obtained by attrition scrubbing and desliming by cyclones. In order to increase the grade of the concentrate, upgrading of the preconcentrate by multigravity was also tried. The two metallurgical routes tested were: Sulphuric acid curing and water leaching; Sulphuric acid baking and subsequent water leaching. The results of the leaching experiments were found to be quite promising. Leach recoveries up to 90% were easily obtainable. In the case of acid baking, hydrofluoric acid recover as a by-product was also possible

  13. Novel Binders and Methods for Agglomeration of Ore

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Kawatra; T. C. Eisele; J. A. Gurtler; K. Lewandowski

    2005-09-30

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily at a reasonable cost. A primary example of this is copper heap leaching, where there are no binders currently encountered in this acidic environment process. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching. The active involvement of our industrial partners will help to ensure rapid commercialization of any agglomeration technologies developed by this project.

  14. Technique for in situ leach simulation of uranium ores

    International Nuclear Information System (INIS)

    Grant, D.C.; Seidel, D.C.; Nichols, I.L.

    1985-01-01

    In situ uranium mining offers the advantages of minimal environmental disturbance, low capital and operating costs, and reduced mining development time. It is becoming an increasingly attractive mining method for the recovery of uranium from secondary ore deposits. In order to better understand the process, a laboratory technique was developed and used to study and simulate both the chemical and physical phenomena occurring in ore bodies during in situ leaching. The laboratory simulation technique has been used to determine effects of leaching variables on permeability, uranium recovery, and post-leach aquifer restoration. This report describes the simulation system and testing procedure in sufficient detail to allow the construction of the system, and to perform the desired leaching tests. With construction of such a system, in situ leaching of a given ore using various leach conditions can be evaluated relatively rapidly in the laboratory. Not only could optimum leach conditions be selected for existing ore bodies, but also exploitation of new ore bodies could be accelerated. 8 references, 8 figures, 2 tables

  15. Novel Binders and Methods for Agglomeration of Ore

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-03-31

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily at a reasonable cost. A primary example of this is copper heap leaching, where there are no binders currently encountered in this acidic environment process. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching. The active involvement of our industrial partners will help to ensure rapid commercialization of any agglomeration technologies developed by this project.

  16. NOVEL BINDERS AND METHODS FOR AGGLOMERATION OF ORE

    Energy Technology Data Exchange (ETDEWEB)

    S.K. Kawatra; T.C. Eisele; J.A. Gurtler; C.A. Hardison; K. Lewandowski

    2004-04-01

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking.

  17. Radon and Thoron emanation testwork on Nolans Rare Earths ores

    International Nuclear Information System (INIS)

    Sonter, Mark; Grose, Jeremy

    2016-01-01

    This paper reports on a series of experiments performed on two bulk ore samples for Arafura Resources' Nolans Rare Earths project, intended to derive information on radon (Rn222) and thoron (Rn220) emanation rates (fluxes) under various circumstances. This data is needed to enable development of predictions of Rn and Tn releases from exposed mine bench ore, ore stockpiles, and tailings, and thus assist in estimation of airborne concentrations within the areas of the future Mine and Processing plant. In turn these estimates will provide guidance on the quantitative risk and the necessity or otherwise of invoking specific control measures, either in design or in operating procedures. This testwork was carried out during the period 2nd to 15th July, at Arafura's Winnellie facility in Darwin. Conclusions are that for uncrushed ore, Rn flux numbers are around 1.0Bq/m"2/s, Tn numbers appear to cluster around 200-300 Bq/m"2/s. Crushing gave no change in Rn flux, Tn flux was doubled for calc-silicate material. Wetting gave significant reductions for both Rn and Tn for ores sampled, and clay capping reduced Rn flux marginally but Tn was reduced by a factor of 100.

  18. PHASE ANALYSES OF URANIUM-BEARING MINERALS FROM THE HIGH GRADE ORE, NOPAL I, PENA BLANCA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    M. Ren; P. Goodell; A. Kelts; E.Y. Anthony; M. Fayek; C. Fan; C. Beshears

    2005-07-11

    The Nopal I uranium deposit is located in the Pena Blanca district, approximately 40 miles north of Chihuahua City, Mexico. The deposit was formed by hydrothermal processes within the fracture zone of welded silicic volcanic tuff. The ages of volcanic formations are between 35 to 44 m.y. and there was secondary silicification of most of the formations. After the formation of at least part of the uranium deposit, the ore body was uplifted above the water table and is presently exposed at the surface. Detailed petrographic characterization, electron microprobe backscatter electron (BSE) imagery, and selected x-ray maps for the samples from Nopal I high-grade ore document different uranium phases in the ore. There are at least two stages of uranium precipitation. A small amount of uraninite is encapsulated in silica. Hexavalent uranium may also have been a primary precipitant. The uranium phases were precipitated along cleavages of feldspars, and along fractures in the tuff. Energy dispersive spectrometer data and x-ray maps suggest that the major uranium phases are uranophane and weeksite. Substitutions of Ca and K occur in both phases, implying that conditions were variable during the mineralization/alteration process, and that compositions of the original minerals have a major influence on later stage alteration. Continued study is needed to fully characterize uranium behavior in these semi-arid to arid conditions.

  19. Improvements on heap leaching process for a refractory uranium ore and yellow cake precipitation process

    International Nuclear Information System (INIS)

    Feng Jianke

    2013-01-01

    Some problems such as formed harden matrix, ore heap compaction, poor permeability, and agglomeration of absorption resin occur during extracting uranium from a refractory uranium ore by heap leaching process. After some measures were taken, i.e. spraying a new ore heap by low concentration acid, two or more ore heaps in series leaching, turning ores in ore heap, the permeability was improved, acid consumption was reduced. Through precipitate circulation and aging, the yellow cake slurry in amorphous or microlite form was transformed to crystal precipitate, thus uranium content in yellow cake was improved, and water content in yellow cake was lowered with good economic benefits. (author)

  20. Uranium Rirang ore processing: extraction of uranium from Rirang ore digestion solution with tributyl phosphate

    International Nuclear Information System (INIS)

    Arief, E. R.; Zahardi; Susilaningtyas

    1998-01-01

    Uranium is extracted from Rirang ore acid digestion solution containing rare earths. A mixture of tributyl phosphate solvent and kerosene diluent is employed. Several parameters of solvent extraction have been studied included aqueous to organic phase ratio, H 2 O 2 reductor concentration and Tbp concentration in the solvent mixture, as well as the aqueous to organic phase ratio in the stripping process. The optimum conditions for the extraction step include the use of 25% H 2 O 2 (v/v), one to one aqueous to organic ratio, and 40% Tbp in kerosene. The extraction recovery for U, RE, Th, and PO 4 3 - are 99%, 4%, 70%, and 30%, respectively. The stripping step optimum conditions include the use of one to five organic to aqueous phase ratio 0.24 N HNO 3 . and the stripping recovery for U, RE, Th, and PO 4 3 - are 84%, 80%, 72%, and 83%, respectively

  1. Geostatistical Approach to Estimating the Gold Ore Characteristics and Gold Reserves: A Case Study Daksa Area, Quang Nam Province, Viet Nam

    Science.gov (United States)

    Luan Truong, Xuan; Luong Le, Van; Quang Truong, Xuan

    2015-04-01

    Daksa gold deposit is the biggest gold deposits in Vietnam. The Daksa geological structure complicated, distributed mainly metamorphosed sedimentary NuiVu formation (PR3-?1nv2). The sulfide gold ore bodies distributed in quartz schist, quartz - biotite related to faut and distribution wing anticline. The gold ore bodies form circuits, network circuits, circuits lenses; fill the cup surface layer of the developing northeast - southwest; is the less than or west longitude north - SE. The results show that, Au and accompanying elements (Ag, Pb and Zn) have correlated pretty closely. All of its consistent with the logarithmic distribution standard, in accordance with the law of distribution of content mineral rare. The structure functions have nugget effect and spherical models with show that Au and accompanying elements special variation are changes. Au contents shown local anisotropy, no clearly anisotropy (K=1,17) and weakly anisotropy (K=1,4). Intensity mineralization of the ore bodies are quite high with demand spherical conversion coefficient ranging from 0.49 to 0.75 and from 0.66 to 0.97 (for other body). With nugget effects, ore bodies shown that it is consistent with mineralization in the ore bodies study, ore erasable, micro vein, infilling fractures in quartz vein. All of variogram presents local anisotropy, indicated gold mineralization at study area has least two-mineralization stages, consistent with the analysis of mineralography samples. By the results of the structure function study, the authors present the system optimization for exploration deposit and used to evaluate gold reserves by Ordinary Kriging. High accuracy of Kriging estimation results are expressed in the minimum Kriging variance, by compare the results calculated by some other methods (such as distance inverse weighting method, ..) and specially compare to the results of a some blocks have been exploited. Key words: Geostat and gold deposits VN. Daksa and gold mineralization. Geostat

  2. Seismicity induced by mining operations in the surrounding of the uranium ore mine Schlema-Alberoda

    International Nuclear Information System (INIS)

    Wallner, Olaf; Hiller, Axel

    2013-01-01

    The uranium mine Schlema-Alberoda of the Wismut GmbH (Chemnitz, Federal Republic of Germany) is situated in the Westerzgebirge between the villages Aue, Schneeberg and Hartenstein. This 22 km 2 large area contains the villages Bad Schlema with the districts Oberschlema, Niederschlema and Wildbach as well as the district Alberode of the village Aue. The most important waters are the Zwickauer Mulde flowing through this territory from the south to the north. This territory can be designated as a densely populated low mountain range landscape being characterized by mining operations for centuries. Subsequently to the year 1945, the former Soviet 'Saxonian mining administration' started the first explorations on uranium ores inter alia in the area around Schneeberg and Schlema. In the year 1946, the intensive exploration and exploitation began in the health resort Oberschlema well-known by the existence of water containing radium. Up to the year 1959, the part deposit Oberschlema was dismantled. The dismantling ranged till to a depth of 750 m. With the expansion of the explorations in north-western direction, in 1948 the first uranium containing corridors of the part deposit Niederschlema-Alberoda was verified. The mining activities began in the year 1949 and culminated in the midst of the 1960ies with an annual production of more than 4,000 tons of uranium. The 1,800 m floor level as the deepest floor level was reached in the year 1986. A total of 49.5 million cubic meters of rocks was dissolved, and a total of 80,500 tons of uranium ores was mined. These were nearly 35% of the total production of the former Soviet-German public limited company Wismut (SDAG Wismut).

  3. The role of metasomatism in the balance of halogens in ore-forming process at porphyry Cu-Mo deposits

    Science.gov (United States)

    Berzina, A. N.

    2009-04-01

    Volatile components play an important role in the evolution of ore-magmatic systems and their ore potential. Of special interest are fluorine and chlorine compounds that principally control the transportation of ore elements by the fluid in a magmatic process and under high-temperature hydrothermal conditions. Study of the evolution of fluorine-chlorine activity in the ore-forming process and their source is usually based on analysis of their magmatic history, whereas the additional source of fluorine and chlorine released during metasomatic alteration of rocks hosting mineralization is poorly discussed in the existing literature. Based on microprobe data on Cl and F abundances in halogen-containing minerals (biotite, amphibole, apatite, titanite) in intrusive rocks and their hydrothermally altered varieties, the role of metasomatic processes in the balance of volatiles in the ore-forming system is discussed by the example of porphyry Cu-Mo deposits of Siberia (Russia) and Mongolia. Two groups of the deposits are considered: copper-molybdenum (Erdenetiin Ovoo, Mongolia and Aksug, Russia) with prevailing propylitic and phyllic alteration and molybdenum-copper (Sora, Russia), with predominant potassic alteration. All types of hydrothermal alterations have led to drastic decrease in Cl contents in metasomatic minerals as compared with halogen-containing magmatic minerals. All studied deposits (particularly those where propylitic and phyllic alteration were developed) show a nearly complete chlorine removal from altered halogen-containing rock-forming minerals (biotite and amphibole). The Cl content in amphibole decreases several times at the stage of replacement with actinolite in the process of propylitization. In the later chlorites (ripidolite and brunsvigite) that replace amphibole, actinolite, and biotite, chlorine is not detected by microprobe (detection limit 0.01-0.02% Cl). Chlorine was also not detected in white micas (muscovite-phengite series) in quartz

  4. The Technological Mineralogical Research of Molybdenum in Skarn-type Ore of Huangshaping Polymetallic Mining Area, Hunan, China

    Science.gov (United States)

    Liu, W. H.; Pan, J. Y.

    2017-10-01

    Huangshaping is one of the most important polymetallic deposits in the south of Hunan Province. Through field investigation, chemical analysis, observation under the optical microscope, energy spectrum analysis of the SEM and X-ray diffraction, the author made a technological mineralogical research of molybdenum on skarn-type ore, and the result shows that the ore containing molybdenum is mainly on the contact of the granite porphyry and the impure limestone in the lower carboniferous Shidengzi group. Besides molybdenum, the ore minerals contain scheelite, native bismuth, bismuthinite, magnetite and so on; and the gangue minerals are mainly andradite, fluorite and wollastonite. Part of the molybdenum exists in the scheelite in form of isomorphism, and there is an obvious negative correlation between MoO3 and WO3. The molybdenite granularity is mainly located in the 0.04~ 0.08mm area, which accounts for 29.5% of the total and is the finely disseminated ore. For samples of 70%, 90%, and 100% with the particle size of more than 200 meshes, the maximum recovery of the molybdenite are 75.15%, 86.45% and 91.25% respectively. So there will be a better use of molybdenum if we properly improve the grinded particle size of the comprehensive samples. As part of the molybdenum is distributed in the scheelite lattice, the actual recovery rate in this area may decline compared with the ideal value.

  5. Sintering-alkaline processing of borosilicate ores of Tajikistan

    International Nuclear Information System (INIS)

    Nazarov, F.A.

    2018-01-01

    The aim of the work is to study the processes of decomposition of boron-containing ore by sintering with NaOH, finding the optimal parameters of the decomposition process, studying the kinetics of processes and developing the technological foundations for ore processing. The processes of borosilicate ore processing were studied by sintering with NaOH. Possible mechanisms of chemical reactions of the process of sintering-alkaline decomposition of boron-containing ore are established, the results of which are substantiated by physicochemical methods of analysis. A principal technological scheme for processing of borosilicate ores by a sintering-alkaline method has been developed. In the first chapter, data on alkaline and caking processes for processing boron-containing and aluminium comprising raw materials are available in the literature. Based on this, the directions of our own research are outlined. The second chapter is devoted to the study of the chemical and mineralogical compositions of borosilicate ores and their concentrates with the help of X-ray phase and chemical analysis methods, the stoichiometric calculation of the formation of aluminum, iron, and boron salts has been carried out, and a thermodynamic analysis of the processes of sintering borosilicate ores with alkali has been considered. The third chapter presents the results of a study of sintering-alkaline method of processing of initial borosilicate ore of the Ak-Arkhar Deposit and its concentrate without calcination and after calcination. The kinetics of sintering of borosilicate ores with sodium hydroxide was studied. The optimal conditions of borosilicate ore sintering before and after the preliminary calcination with alkali were determined. Optimal parameters of the sintering process have been found: sintering temperature 800-8500 deg C, duration of the process - 60 minutes, mass ratio of NaOH to raw materials 2: 1. The conditions for sintering of borosilicate concentrate with alkali have been

  6. Dynamics of leaching a uniformly fissured ore body

    International Nuclear Information System (INIS)

    Ignatov, A.A.; Proskurin, S.A.

    1987-01-01

    Mathematical simulation was used to study the dynamics of mass transfer during the percolation of a reagent solution through a packing of coarse ore particles. The uniformly fissured ore body was represented by a cubic packing of spherical particles of constant radius, formed from a chemically inert silicate cement with a uniformly distributed soluble mineral component. The rate of percolation of the reagent through the packing was constant. The proposed model can be used to find the conditions for underground hydrodynamic leaching. The rate of non-catalytic solid-liquid reaction was deduced on the basis of both the kinetics of dissolution of the mineral component of the ore and the rate of diffusion of the dissolved substance

  7. Beneficiation of the gold bearing ore by gravity and flotation

    Science.gov (United States)

    Gül, Alim; Kangal, Olgaç; Sirkeci, Ayhan A.; Önal, Güven

    2012-02-01

    Gold concentration usually consists of gravity separation, flotation, cyanidation, or the combination of these processes. The choice among these processes depends on the mineralogical characterization and gold content of the ore. Recently, the recovery of gold using gravity methods has gained attention because of low cost and environmentally friendly operations. In this study, gold pre-concentrates were produced by the stepwise gravity separation and flotation techniques. The Knelson concentrator and conventional flotation were employed for the recovery of gold. Gold bearing ore samples were taken from Gümüşhane Region, northern east part of Turkey. As a result of stepwise Knelson concentration experiments, a gold concentrate assaying around 620 g/t is produced with 41.4wt% recovery. On the other hand, a gold concentrate about 82 g/t is obtained with 89.9wt% recovery from a gold ore assaying 6 g/t Au by direct flotation.

  8. Complex sulphide-barite ore leaching in ferric chloride solution

    Directory of Open Access Journals (Sweden)

    Miroslav Sokić

    2016-06-01

    Full Text Available The results of research on the leaching process of complex sulphide-barite ore were presented in this paper. The leaching process was carried out in a laboratory autoclave by ferric chloride solution. Considering that those minerals are represented in complex structural-textural relationships, it is not possible to extract lead, zinc and copper minerals from ore by flotation methods. The obtained results confirmed possibility of the ore processing directly, by chemical methods. The effect of temperature, time and oxygen partial pressure on the lead, zinc and copper dissolution was studied. The maximal leaching degree was achieved at 100 °C and amount of 91.5 % for Pb, 96.1 % for Zn and 60.7 % for Cu. Leaching at temperatures above 100 °C is impractical.

  9. Ore-processing technology and the uranium supply outlook

    International Nuclear Information System (INIS)

    James, H.E.; Simonsen, H.A.

    1978-01-01

    The subject is covered in sections, as follows: the resource base (uranium content of rocks, regional distribution of Western World uranium); ore types (distribution of Western World uranium, by ore types, response to ore-processing); constraints on expansion in traditional uranium areas (defined for this paper as the sandstone deposits of the U.S.A. and the quartz-pebble conglomerates of the Witwatersrand and Elliot Bay areas, all other deposits being referred to as new uranium areas). Sections then follow dealing in detail with the processing of deposits in U.S.A., South Africa, Canada, Niger, Australia, South West Africa, Greenland. More general sections follow on: shale, lignite and coal deposits, calcrete deposits. Finally, there are sections on: uranium as a by-product; uranium from very low-grade resources; constraints on expansion rate for production facilities. (U.K.)

  10. Aluminum chloride restoration of in situ leached uranium ores

    International Nuclear Information System (INIS)

    Grant, D.C.; Burgman, M.A.

    1982-01-01

    During in situ uranium mining using ammonium bicarbonate lixiviant, the ammonium exchanges with cations on the ore's clay. After mining is complete, the ammonium may desorb into post-leach ground water. For the particular ore studied, other chemicals (i.e., uranium and selenium) which are mobilized during the leach process, have also been found in the post-leach ground water. Laboratory column tests, used to simulate the leaching process, have shown that aluminum chloride can rapidly remove ammonium from the ore and thus greatly reduce the subsequent ammonium leakage level into ground water. The aluminum chloride has also been found to reduce the leakage levels of uranium and selenium. In addition, the aluminum chloride treatment produces a rapid improvement in permeability

  11. The production and use of citric acid for the removal of potassium from the iron ore concentrate of the Sishen Iron Ore Mine, South Africa

    Directory of Open Access Journals (Sweden)

    Peter J. Williams

    2010-04-01

    Full Text Available The depletion of the richer iron ore worldwide has made it necessary to process lower quality iron ore. Certain substances, such as potassium, contained within the lower quality iron ore, have a detrimental effect on the smelting process during steel manufacturing. Therefore, international steel-making companies charge penalties when purchasing iron ore concentrates containing high concentrations of potassium. To date, lower quality iron ore has been blended with high quality iron ore in an attempt to alleviate the potassium concentrations in the export iron ore; however, the ratio of low quality iron ore to high quality iron ore is increasing, thereby becoming an escalating problem within the economic functioning of the Sishen Iron Ore Mine. It has, therefore, become necessary to develop an economically viable and environmentally friendly process to reduce the high potassium concentrations contained in the iron ore concentrate of the Sishen Iron Ore Mine. In this study, we compared solid substrate and submerged fermentation using Aspergillus niger for the production of citric acid, which is used for the chemical leaching of potassium from the iron ore concentrate. It was found that submerged fermentation proved to be more economical and efficient, producing a maximum citric acid concentration of 102.3 g/L in 96 h of fermentation. ‘Heap leaching’ simulation experiments were found to be uneconomical, due to the required addition of fungal growth medium every 5 days as a result of growth factor depletion within this time; however, this process removed 17.65% of the potassium from the iron ore concentrate. By contrast, chemical leaching of potassium from the iron ore concentrate proved to be most efficient when using a 1 mol citric acid leaching solution at 60 ºC, removing 23.53% of the potassium contained within the iron ore concentrate. Therefore, the most economical and efficient process for the removal of potassium from the iron

  12. Chloride pyrometallurgy of uranium ore. 1. Chlorination of phosphate ore using solid or gas chlorinating agent and carbon

    International Nuclear Information System (INIS)

    Taki, Tomihiro; Komoto, Shigetoshi; Otomura, Keiichiro; Takenaka, Toshihide; Sato, Nobuaki; Fujino, Takeo.

    1995-01-01

    A thermodynamical and pyrometallurgical study to recover uranium from the phosphate ores was undertaken using the chloride volatilization method. Iron was chlorinated with solid chlorinating agents such as NaCl and CaCl 2 in combination with activated carbon, which will be used for removing this element from the ore, but uranium was not. On the other hand, the chlorination using Cl 2 gas and activated carbon gave a good result at 1,223 K. Not only uranium but also iron, phosphorus, aluminum and silicon were found to form volatile chlorides which vaporized out of the ore, while calcium remained in the ore as non-volatile CaCl 2 . The chlorination condition was studied as functions of temperature, reaction time and carbon content. The volatilization ratio of uranium around 95% was obtained by heating the mixture of the ore and activated carbon (35 wt%) in a mixed gas flow of Cl 2 (200 ml/min) and N 2 (200 ml/min) at 1,223 K for 120 min. (author)

  13. [Assessment of Soil Fluorine Pollution in Jinhua Fluorite Ore Areas].

    Science.gov (United States)

    Ye, Qun-feng; Zhou, Xiao-ling

    2015-07-01

    The contents of. soil total fluorine (TF) and water-soluble fluorine (WF) were measured in fluorite ore areas located in Jinhua City. The single factor index, geoaccumulation index and health risk assessment were used to evaluate fluorine pollution in soil in four fluorite ore areas and one non-ore area, respectively. The results showed that the TF contents in soils were 28. 36-56 052. 39 mg.kg-1 with an arithmetic mean value of 8 325.90 mg.kg-1, a geometric mean of 1 555. 94 mg.kg-1, and a median of 812. 98 mg.kg-1. The variation coefficient of TF was 172. 07% . The soil WF contents ranged from 0. 83 to 74. 63 mg.kg-1 with an arithmetic mean value of 16. 94 mg.kg-1, a geometric mean of 10. 59 mg.kg-1, and a median of 10. 17 mg.kg-1. The variation coefficient of WF was 100. 10%. The soil TF and WF contents were far higher than the national average level of the local fluorine epidemic occurrence area. The fluoride pollution in soil was significantly affected by human factors. Soil fluorine pollution in Yangjia, Lengshuikeng and Huajie fluorite ore areas was the most serious, followed by Daren fluorite ore area, and in non-ore area there was almost no fluorine pollution. Oral ingestion of soils was the main exposure route. Sensitivity analysis of model parameters showed that children's weight exerted the largest influence over hazard quotient. Furthermore, a significant positive correlation was found among the three kinds of evaluation methods.

  14. Novel Binders and Methods for Agglomeration of Ore

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-12-31

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking. This project has identified several acid-resistant binders and agglomeration procedures that can be used for improving the energy efficiency of heap leaching, by preventing the ''ponding'' and ''channeling'' effects that currently cause reduced recovery and extended leaching cycle times. Methods have also been developed for iron ore

  15. Isolation and identification of iron ore-solubilising fungus

    Directory of Open Access Journals (Sweden)

    Damase Khasa

    2010-09-01

    Full Text Available Potential mineral-solubilising fungi were successfully isolated from the surfaces of iron ore minerals. Four isolates were obtained and identified by molecular and phylogenetic methods as close relatives of three different genera, namely Penicillium (for isolate FO, Alternaria (for isolates SFC2 and KFC1 and Epicoccum (for isolate SFC2B. The use of tricalcium phosphate (Ca3(PO42in phosphate-solubilising experiments confirmed isolate FO as the only phosphate solubiliser among the isolated fungi. The bioleaching capabilities of both the fungus and its spent liquid medium were tested and compared using two types of iron ore materials, conglomerate and shale, from the Sishen Iron Ore Mine as sources of potassium (K and phosphorus (P. The spent liquid medium removed more K (a maximum of 32.94% removal, from conglomerate, than the fungus (a maximum of 21.36% removal, from shale. However, the fungus removed more P (a maximum of 58.33% removal, from conglomerate than the spent liquid medium (a maximum of 29.25% removal, from conglomerate. The results also indicated a potential relationship between the removal of K or P and the production of organic acids by the fungus. A high production of gluconic acid could be related to the ability of the fungus to reduce K and P. Acetic, citric and maleic acids were also produced by the fungus, but in lower quantities. In addition, particle size and iron ore type were also shown to have significant effects on the removal of potassium and phosphorus from the iron ore minerals. We therefore conclude that the spent liquid medium from the fungal isolate FO can potentially be used for biobeneficiation of iron ore minerals.

  16. Mining activities of the Cogema group; Activite miniere du groupe Cogema

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-12-31

    This brochure is a general presentation of the mining activities of the COGEMA group. COGEMA is specialized in the whole operations of the nuclear fuel cycle and is responsible for about 20% of the worldwide uranium production with the exploitation of French mines and its participation in the exploitation of mines abroad, mainly in Canada, USA, Niger and Gabon. This document is divided in seven chapters: the search for uranium ores and the mining prospecting, the uranium deposits and the worldwide market, the exploitation of uranium ores (techniques and mines exploited by the COGEMA group), the processing of ores, the radioactivity and the mining installations, the environmental protection and the rehabilitation of sites (environmental survey and management of mining sites), application of COGEMA`s know-how to other domains such as: gold ore processing, research and development studies, instrumentation and radioprotection, soils cleansing and sites rehabilitation. This brochure is illustrated with several photos and pictures. (J.S.).

  17. Utilisation of iron ore tailings as aggregates in concrete

    OpenAIRE

    Francis Atta Kuranchie; Sanjay Kumar Shukla; Daryoush Habibi; Alireza Mohyeddin

    2015-01-01

    Sustainable handling of iron ore tailings is of prime concern to all stakeholders who are into iron ore mining. This study seeks to add value to the tailings by utilising them as a replacement for aggregates in concrete. A concrete mix of grade 40 MPa was prepared in the laboratory with water–cement ratio of 0.5. The concrete were cured for 1, 2, 3, 7, 14 and 28 days. The properties of the concrete such as workability, durability, density, compressive strength and indirect tensile strength we...

  18. Bioleaching of copper oxide ore by Pseudomonas aeruginosa

    Science.gov (United States)

    Shabani, M. A.; Irannajad, M.; Azadmehr, A. R.; Meshkini, M.

    2013-12-01

    Bioleaching is an environmentally friendly method for extraction of metal from ores. In this study, bioleaching of copper oxide ore by Pseudomonas aeruginosa was investigated. Pseudomonas aeruginosa is a heterotrophic bacterium that can produce various organic acids in an appropriate culture medium, and these acids can operate as leaching agents. The parameters, such as particle size, glucose percentage in the culture medium, bioleaching time, and solid/liquid ratio were optimized. Optimum bioleaching conditions were found as follows: particle size of 150-177 μm, glucose percentage of 6%, bioleaching time of 8 d, and solid/liquid ratio of 1:80. Under these conditions, 53% of copper was extracted.

  19. Helium and deuterium permeability in O-rings

    International Nuclear Information System (INIS)

    Lakner, J.F.

    1976-01-01

    To obtain more information on gas permeation through elastomeric O-rings, studies were performed on Parker Seal Company O-rings, Nos. 2-113, 2-006, 3-904, and 3-906, all made of a nitrile rubber. Also included in the tests was a valve packing (Autoclave Engineers) encased in AE Valve 20A-2142. Permeation experiments were run usually in duplicate to 82.7 MPa (12,000 psi) with helium and deuterium at room temperature. The data are extrapolated to give values for tritium

  20. Can micro-PIXE measurements help to determine ore genesis ?

    International Nuclear Information System (INIS)

    Ahmed, M.; Al-Ohali, M.A.

    2002-01-01

    This study is an attempt to demonstrate how the nuclear micro-PIXE technique can be utilized to investigate ore genesis of geological deposits. Elemental concentrations and distribution profiles in single mineral grains and matrices in a present-day ore deposit on land were measured using the scanning proton microprobe on the 3 MV Tandetron accelerator at King Fahd University of Petroleum and Minerals. Comparing the distribution profiles of some of the trace elements detected it was possible to suggest an organic, sea origin of these deposits. (Author)

  1. Underground Milling of High-Grade Uranium Ore

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, C., E-mail: chuck.edwards@amec.com [AMEC Americas Limited, Saskatoon, Saskatchewan (Canada)

    2014-05-15

    There are many safety and technical issues involved in the mining and progressing of high grade uranium ores such as those exploited in Northern Canada at present. With more of this type of mine due to commence production in the near future, operators have been looking at ways to better manage the situation. The paper describes underground milling of high-grade uranium ore as a means of optimising production costs and managing safety issues. In addition the paper presents some examples of possible process flowsheets and plant layouts that could be applicable to such operations. Finally an assessment of potential benefits from underground milling from a variety of viewpoints is provided. (author)

  2. Chemical separation of Th-230 from uranium ore

    International Nuclear Information System (INIS)

    Kikunaga, H.; Nakanishi, T.; Mitsugashira, T.; Hara, M.

    2001-01-01

    We are studying the decay processes of low energy nuclear isomer of Th-229. Our approach to produce Th-229m is (γ, n) reaction on Th-230, hence, about 100 μg of Th-230 is necessary as a target. However, our stock of Th-230 has run out during several experiments, thus, we tried to separate Th-230 from uranium ore. In this paper, the detail of a chemical separation procedure for Th-230 from uranium ore and the results are reported. (author)

  3. Oxidizing attack process of uranium ore by a carbonated liquor

    International Nuclear Information System (INIS)

    Maurel, Pierre; Nicolas, Francois.

    1981-01-01

    A continuous process for digesting a uraniferous ore by oxidation with a recycling aqueous liquor containing alkaline carbonates and bicarbonates in solution as well as uranium in a concentration close to its solubility limit at digestion temperature, and of recuperation of the precipitated uranium within the solid phase remaining after digestion. The digestion is carried out by spraying oxygen into the hot reactional medium in order not only to permit oxidation of the uranium and its solubilization but also to ensure that the sulphides of impurities and organic substances present in the ore are oxidized [fr

  4. Study of the dry processing of uranium ores

    International Nuclear Information System (INIS)

    Guillet, H.

    1959-02-01

    A description is given of direct fluorination of pre-concentrated uranium ores in order to obtain the hexafluoride. After normal sulfuric acid treatment of the ore to eliminate silica, the uranium is precipitated by a load of lime to obtain: either impure calcium uranate of medium grade, or containing around 10% of uranium. This concentrate is dried in an inert atmosphere and then treated with a current of elementary fluorine. The uranium hexafluoride formed is condensed at the outlet of the reaction vessel and may be used either for reduction to tetrafluoride and the subsequent manufacture of uranium metal or as the initial product in a diffusion plant. (author) [fr

  5. First aid to fight hazards at the uranium ore processing plant at Seelingstaedt/Thuringia

    International Nuclear Information System (INIS)

    Gellermann, R.; Molitor, N.; Ripper, P.

    1991-01-01

    Mining for uranium ore in Saxonia and Thuringen under the ownership of the German-Soviet group SDAG Wismut has severely affected the environment in the concerned regions over the last 45 years. By means of a special project, the article gives an overview of hazard potentials, acute hazards and envisaged first aid, as well as on additional measures to restore and revegetate the landscape. The state of knowledge on which the article is based is as at June 1991. (orig./HP) [de

  6. Assessing radiological impacts (exposures and doses) associated with the mining and milling of radioactive ores

    International Nuclear Information System (INIS)

    Williams, G.A.

    1990-01-01

    The basic units and concepts applicable to radiological assessment are presented. Data relevant to the assessment of radiological exposures from the mining and milling phases of uranium and thorium ores are discussed. As a guide to the assessment of environmental exposures to members of the public, concepts such as the critical group are defined. Environmental transport and exposure pathways are presented in general terms, together with a discussion of the use of mathematical models. The dose assessment procedures defined in the 1987 Code of Practice are described. 13 refs., 2 tabs., 1 fig

  7. A study of the distribution of rare-metals in kuroko-type ore

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience]|[Geological Survey of Japan, Tsukuba, Ibaraki (Japan); Sie, S.H.; Suter, G.F. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

    1996-12-31

    We have performed PIXE analysis of kuroko-type ore from the JADE hydrothermal site of the Okinawa Trough, Japan using the proton microprobe (PIXEPROBE). We analysed five kinds of ores dredged from the sea floor: (I) barite ore with small sulfide dissemination; (2) sphalerite-pyrite chimney; (3) pyrite ore; (4) sulfide veinlets in strongly altered rock; and (5) pyrite megacrystals in strongly altered rock. The analyses revealed that the trace element distribution is regulated by the occurrence mode of the ore, and within each ore, by the crystal structure. The distribution suggests that the hydrothermal system for kuroko ore formation is quite heterogeneous and its chemistry is controlled by local factors such as difference in temperature, and that in-situ PIXE analyses are essential for effective beneficiation strategy for the rare-metals from kuroko-type ore. (authors). 10 refs., 1 tab.

  8. A study of the distribution of rare-metals in kuroko-type ore

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience; [Geological Survey of Japan, Tsukuba, Ibaraki (Japan); Sie, S H; Suter, G F [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

    1997-12-31

    We have performed PIXE analysis of kuroko-type ore from the JADE hydrothermal site of the Okinawa Trough, Japan using the proton microprobe (PIXEPROBE). We analysed five kinds of ores dredged from the sea floor: (I) barite ore with small sulfide dissemination; (2) sphalerite-pyrite chimney; (3) pyrite ore; (4) sulfide veinlets in strongly altered rock; and (5) pyrite megacrystals in strongly altered rock. The analyses revealed that the trace element distribution is regulated by the occurrence mode of the ore, and within each ore, by the crystal structure. The distribution suggests that the hydrothermal system for kuroko ore formation is quite heterogeneous and its chemistry is controlled by local factors such as difference in temperature, and that in-situ PIXE analyses are essential for effective beneficiation strategy for the rare-metals from kuroko-type ore. (authors). 10 refs., 1 tab.

  9. Excursions at the places of mining and processing ore resources in Slovakia. The second part

    International Nuclear Information System (INIS)

    Jesenak, K.

    2011-01-01

    The second part of this text-book brings a complex and comprehensive view on the places of mining and processing of ore resources in the Slovak Republic. Environmental impact of mining and processing of the ores is also presented.

  10. A study of the distribution of rare-metals in kuroko-type ore

    International Nuclear Information System (INIS)

    Murao, S.; Sie, S.H.; Suter, G.F.

    1996-01-01

    We have performed PIXE analysis of kuroko-type ore from the JADE hydrothermal site of the Okinawa Trough, Japan using the proton microprobe (PIXEPROBE). We analysed five kinds of ores dredged from the sea floor: (I) barite ore with small sulfide dissemination; (2) sphalerite-pyrite chimney; (3) pyrite ore; (4) sulfide veinlets in strongly altered rock; and (5) pyrite megacrystals in strongly altered rock. The analyses revealed that the trace element distribution is regulated by the occurrence mode of the ore, and within each ore, by the crystal structure. The distribution suggests that the hydrothermal system for kuroko ore formation is quite heterogeneous and its chemistry is controlled by local factors such as difference in temperature, and that in-situ PIXE analyses are essential for effective beneficiation strategy for the rare-metals from kuroko-type ore. (authors). 10 refs., 1 tab

  11. Utilizing a Value of Information Framework to Improve Ore Collection and Classification Procedures

    National Research Council Canada - National Science Library

    Phillips, Julia A

    2006-01-01

    .... We use a value of information framework (VOI) to consider the economic feasibility of a mine purchasing additional information on extracted ore type to reduce the uncertainty of extracted ore grade quality...

  12. Composite correlation filter for O-ring detection in stationary colored noise

    Science.gov (United States)

    Hassebrook, Laurence G.

    2009-04-01

    O-rings are regularly replaced in aircraft and if they are not replaced or if they are installed improperly, they can result in catastrophic failure of the aircraft. It is critical that the o-rings be packaged correctly to avoid mistakes made by technicians during routine maintenance. For this reason, fines may be imposed on the o-ring manufacturer if the o-rings are packaged incorrectly. That is, a single o-ring must be packaged and labeled properly. No o-rings or more than one o-ring per package is not acceptable. We present an industrial inspection system based on real-time composite correlation filtering that has successfully solved this problem in spite of opaque paper o-ring packages. We present the system design including the composite filter design.

  13. Rock-magnetism and ore microscopy of the magnetite-apatite ore deposit from Cerro de Mercado, Mexico

    Science.gov (United States)

    Alva-Valdivia, L. M.; Goguitchaichvili, A.; Urrutia-Fucugauchi, J.; Caballero-Miranda, C.; Vivallo, W.

    2001-03-01

    Rock-magnetic and microscopic studies of the iron ores and associated igneous rocks in the Cerro de Mercado, Mexico, were carried out to determine the magnetic mineralogy and origin of natural remanent magnetization (NRM), related to the thermo-chemical processes due to hydrothermalism. Chemical remanent magnetization (CRM) seems to be present in most of investigated ore and wall rock samples, replacing completely or partially an original thermoremanent magnetization (TRM). Magnetite (or Ti-poor titanomagnetite) and hematite are commonly found in the ores. Although hematite may carry a stable CRM, no secondary components are detected above 580°, which probably attests that oxidation occurred soon enough after the extrusion and cooling of the ore-bearing magma. NRM polarities for most of the studied units are reverse. There is some scatter in the cleaned remanence directions of the ores, which may result from physical movement of the ores during faulting or mining, or from perturbation of the ambient field during remanence acquisition by inhomogeneous internal fields within these strongly magnetic ore deposits. The microscopy study under reflected light shows that the magnetic carriers are mainly titanomagnetite, with significant amounts of ilmenite-hematite minerals, and goethite-limonite resulting from alteration processes. Magmatic titanomagnetites, which are found in igneous rocks, show trellis, sandwich, and composite textures, which are compatible with high temperature (deuteric) oxy-exsolution processes. Hydrothermal alteration in ore deposits is mainly indicated by martitization in oxide minerals. Grain sizes range from a few microns to >100 mm, and possible magnetic state from single to multidomain, in agreement with hysteresis measurements. Thermal spectra, continuous susceptibility measurements, and IRM (isothermal remanent magnetization) acquisition suggest a predominance of spinels as magnetic carriers, most probably titanomagnetites with low

  14. Multi-Criteria selection of technology for processing ore raw materials

    Science.gov (United States)

    Gorbatova, E. A.; Emelianenko, E. A.; Zaretckii, M. V.

    2017-10-01

    The development of Computer-Aided Process Planning (CAPP) for the Ore Beneficiation process is considered. The set of parameters to define the quality of the Ore Beneficiation process is identified. The ontological model of CAPP for the Ore Beneficiation process is described. The hybrid choice method of the most appropriate variant of the Ore Beneficiation process based on the Logical Conclusion Rules and the Fuzzy Multi-Criteria Decision Making (MCDM) approach is proposed.

  15. Influence of the Moisture Content on the Flowability of Fine-Grained Iron Ore Concentrate

    OpenAIRE

    C. Lanzerstorfer; M. Hinterberger

    2017-01-01

    The iron content of the ore used is crucial for the productivity and coke consumption rate in blast furnace pig iron production. Therefore, most iron ore deposits are processed in beneficiation plants to increase the iron content and remove impurities. In several comminution stages, the particle size of the ore is reduced to ensure that the iron oxides are physically liberated from the gangue. Subsequently, physical separation processes are applied to concentrate the iron ore. The fine-graine...

  16. Decomposition of pre calcined aluminium silicate ores of Afghanistan by hydrochloric acid

    International Nuclear Information System (INIS)

    Khomidi, A.K.; Mamatov, E.D.

    2015-01-01

    Present article is devoted to decomposition of pre calcined aluminium silicate ores of Afghanistan by hydrochloric acid. The physicochemical properties of initial aluminium silicate ores were studied by means of X-ray phase, differential thermal and silicate analysis. The chemical composition of aluminium containing ores was determined. The optimal conditions of interaction of initial and pre calcined siallites with hydrochloric acid were defined. The kinetics of acid decomposition of aluminium silicate ores was studied as well.

  17. Nuclear techniques for bulk ore analysis and their application to quality control

    International Nuclear Information System (INIS)

    Holmes, R.J.

    1981-01-01

    Bulk analysis techniques developed for the mining industry in which analyses are obtained directly from 3-30kg ore samples or from ore on conveyor belts are outlined. They include the determination of iron in iron ores from backscattered gamma radiation, shale in sedimentary iron ores from natural gamma activity, iron from a thermal-neutron capture reaction, and aluminium from the thermal neutron activation reaction

  18. Environmental nuclear-geophysical ore monitoring in mines of Corporation Kazakhmys PLC.

    Science.gov (United States)

    Yefimenko, Sergei; Yefimenko, Olga; Makarov, Dmitriy

    2014-01-01

    An environmental monitoring of ore composition in complex deposits of Kazakhstan (the Zhezkazgan, Kusmuryn, Artemjevsk, Kounrad, Taskura and Zhaman-Aibat deposits) is carried out using EDXRF spectrometers RPP-12, RLP-21 and RLP-21T. The monitoring of ore concentrates in Satpaev, Balkhashsk and Zhezkazgan processing plants and in Zhezkazgan copper smelter continues at present time. The monitoring suggests data on new promising elements and environmental pollutants in ores and new trends in distribution of bound elements in ores.

  19. 40 CFR 440.90 - Applicability; description of the antimony ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Applicability; description of the antimony ore subcategory. 440.90 Section 440.90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Antimony Ore Subcategory § 440.90 Applicability;...

  20. Chapter 1. The characteristics of borosilicate ores of Ak-Arkhar Deposit of Tajikistan

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Kurbonov, A.S.; Mamatov, E.D.

    2015-01-01

    Present article is devoted to characteristics of borosilicate ores of Ak-Arkhar Deposit of Tajikistan. The chemical composition of danburite ore of Ak-Arkhar Deposit was defined. The chemical composition of danburite ore concentrate of Ak-Arkhar Deposit was defined as well.

  1. Genesis of iron-apatite ores in Posht-e-Badam Block (Central Iran ...

    Indian Academy of Sciences (India)

    Central Iran; iron-apatite ore; Kiruna-type; Posht-e-Badam Block; REE geochemistry. J. Earth Syst ... ferent ore genesis models have been proposed for ...... volatile-rich magma systems stress the important .... Laco magnetite flow deposits, northern Chile: An up-to- ... economic report on iron ore prevision of the Esfahan steel.

  2. Effects of Ore dust pollution on the physical and chemical features ...

    African Journals Online (AJOL)

    Effects of wind-blown iron and manganese ore dust on the upper part of a sandy beach have been investigated. The fine ore dust was found to reduce the porosity and permeability of the sand by clogging the interstices. The presence of ore dust also greatly increased the rate of heating and cooling of beach sand. Further ...

  3. Proposal for selecting an ore sample from mining shaft under Kvanefjeld

    International Nuclear Information System (INIS)

    Lund Clausen, F.

    1979-02-01

    Uranium ore recovered from the tunnel under Kvanefjeld (Greenland) will be processed in a pilot plant. Selection of a fully representative ore sample for both the whole area and single local sites is discussed. A FORTRAN program for ore distribution is presented, in order to enable correct sampling. (EG)

  4. A field technique for rapid lithological discrimination and ore mineral ...

    Indian Academy of Sciences (India)

    This work illustrates the efficiency of field spectroscopy for rapid identification of minerals in ore body, alteration zone and host rocks. The adopted procedure involves collection of field spectra, their processing for noise, spectral matching and spectral un-mixing with selected library end-members. Average weighted spectral ...

  5. Mining, ore preparation and niobium alloys production at Araxa, Brazil

    International Nuclear Information System (INIS)

    Paraiso, O.S.; Fuccio Junior, R. de; Betz, E.W.

    1984-01-01

    A detailed description of the worlds major niobium producer is presented covering mining, concentration by froth flotation, leaching, and production of ferro-alloys. The present exploration of the Araxa deposit, its ore preparation and production of ferro-niobium is described. (E.G.) [pt

  6. Siltation of Ore Particles in Leaching Tanks: Causative Factors and ...

    African Journals Online (AJOL)

    Michael

    2016-12-02

    Dec 2, 2016 ... In this era of low grade ores and low metal price regimes, most plants now ... factors for siltation of tanks in the Carbon-in-Leach. Plant of Gold Fields Ghana Ltd at ..... interests are in rare earth elements minerals beneficiation ...

  7. Radiation monitoring in the mining and milling of radioactive ores

    International Nuclear Information System (INIS)

    1989-01-01

    The present Guide is a revision of IAEA Safety Series No. 43. It explains the recommendations on administrative requirements for the organization of radiation protection in the mining and milling of radioactive ores, and the monitoring requirements, including methods, techniques, instrumentation and strategy. 146 refs, 9 figs, 14 tabs

  8. Process and equipment for in situ ore leaching

    International Nuclear Information System (INIS)

    Roussel, J.

    1983-01-01

    A solution for the leaching of uranium, cobalt, copper, ... ores is injected then extracted in a recovery well after extraction of the metal the solution is pressurized and oxygenated. During injection the pressure is maintained constant for a maximum oxygenation without bubble formation [fr

  9. Carbothermal Upgrading of the Awaso Bauxite Ore using Sawdust ...

    African Journals Online (AJOL)

    Michael

    2016-12-02

    Dec 2, 2016 ... Bauxite Ore using Sawdust and Coconut Shells as Reductant”, Ghana Mining Journal, Vol. 16, No. 2, pp ... The fruit is consumed locally, producing greater volumes .... made into paste by drop-wise addition of water. The paste ...

  10. Ore levels in Paleozoic of Semipalatinsk test site

    International Nuclear Information System (INIS)

    Ergaliev, G.Kh.; Myasnikov, A.K.; Fomichev, V.I.

    1999-01-01

    The regularity of the deposition of main mineralization of industrial types within Semipalatinsk test site proves and here and there defines more exactly location of the ore levels in Eastern Kazakhstan. Two mega levels, namely: Cambrian-Ordovician (siliceous-basalt, island-arc) and Carboniferous (especially carbonaceous-tarragons) ones are the most perspective for localizing the leading gold mineralization in the region

  11. The expansion of Xiazhuang ore field to be very promising

    International Nuclear Information System (INIS)

    Gong Zhigen

    1993-01-01

    By analyzing the regional geological characteristics and based on the law of tectonic movement matching with the ore-forming solution evolution, it is suggested that there would exist a larger NNE-trending fault structure which is considered as the third main metallogenetic belt

  12. Application of microcomputer to X-ray radiometric ore separation

    International Nuclear Information System (INIS)

    Neverov, A.D.; Aleksandrov, P.S.; Kotler, N.I.

    1988-01-01

    The practical use of microcomputers as universal means for converting information for solving applied problems of X-ray radiometric ore separation method is considered. Laboratory tests of two metals - tungsten and tin manifested high efficiency of the developed system. X-ray radiometric separator software is developed

  13. Equilibria determination in uranium ores by alpha spectrometry

    International Nuclear Information System (INIS)

    Tormo Ferrero, M.J.

    1976-01-01

    A method for the measurement of the U-234/U-238 activities is described. The separation of the uranium from the interferring elements is carried out by ionic change with anionic resine, in chlorhydric-metanol-ascorbic acid medium. The method has been applied to different spanish ores in which the equilibrium state has been determined (author)

  14. Advantage of uranium contained in low grade dolomite ore

    International Nuclear Information System (INIS)

    Carneiro, A.L.M.

    1988-01-01

    The purpose of this work is to investigate a technological route to recover uranium from a lean mineral ore. The experimental work includes studies concerning calcination, carbonate leaching, settling, filtration and resin-ion-exchange. Experimental data confirm the technological feasibility of the proposed process and two different preliminary flowsheets of a pilot plant were suggested. (author) [pt

  15. Composition and method for solution mining of uranium ores

    International Nuclear Information System (INIS)

    Lawes, B.C.; Watts, J.C.

    1981-01-01

    It has been found that, in the solution mining of uranium ores using ammonium carbonate solutions containing hydrogen peroxide or ozone as an oxidant, the tendency of the formation being treated to become less permeable during the leaching process can be overcome by including in the leaching solution a very small concentration of sodium silicate

  16. Rožňava ore field - geophysical works

    Directory of Open Access Journals (Sweden)

    Géczy Július

    1998-12-01

    Full Text Available The article prowides a review of geophysical works in the ore field Rožňava conducted up to date. Magnetometric and geoelectric methods and gravimetric measurements have been used. Geophysical works were focused to the solving regional problems whose contribution to the prospecting of vein deposits is not essential.

  17. Hemimorphite Ores: A Review of Processing Technologies for Zinc Extraction

    Science.gov (United States)

    Chen, Ailiang; Li, Mengchun; Qian, Zhen; Ma, Yutian; Che, Jianyong; Ma, Yalin

    2016-10-01

    With the gradual depletion of zinc sulfide ores, exploration of zinc oxide ores is becoming more and more important. Hemimorphite is a major zinc oxide ore, attracting much attention in the field of zinc metallurgy although it is not the major zinc mineral. This paper presents a critical review of the treatment for extraction of zinc with emphasis on flotation, pyrometallurgical and hydrometallurgical methods based on the properties of hemimorphite. The three-dimensional framework structure of hemimorphite with complex linkage of its structural units lead to difficult desilicification before extracting zinc in the many metallurgical technologies. It is found that the flotation method is generally effective in enriching zinc minerals from hemimorphite ores into a high-grade concentrate for recovery of zinc. Pure zinc can be produced from hemimorphite or/and willemite with a reducing reagent, like methane or carbon. Leaching reagents, such as acid and alkali, can break the complex structure of hemimorphite to release zinc in the leached solution without generation of silica gel in the hydrometallurgical process. For optimal zinc extraction, combing flotation with pyrometallurgical or hydrometallurgical methods may be required.

  18. Flotation of uranium from uranium ores in Canada. Part 2

    International Nuclear Information System (INIS)

    Muthuswami, S.V.; Vijayan, S.; Woods, D.R.

    1985-01-01

    Measurements are reported for the equilibrium of cupferron from solutions by uranium oxide, quartz, illite, a mixture of these three, pitchblende, pyrite and brannerite ore. The cupferron concentration ranged from 1 to 6 g/L, and the pH was 7 and 8. Most isotherms followed the Langmuir model, although Freundlich behaviour was observed for illite and pitchblende. Most adsorption was pH independent except for illite and pitchblende. The adsorption isotherms for a mixture of uranium oxide, quartz and illite in the same proportions as in the naturally occurring ore agreed with the adsorption of the pyrite-free ore at pH 8 but not pH 7. We attribute the discrepancy to the use of illite as the model clay. The specific adsorption of cupferron on quartz and illite is lower by a factor of about 50 and 5, respectively, than the adsorption on uranium oxide. Specific adsorption less than 1 mg cupferron per gm of pyrite free ore does not float the mineral. The corresponding equilibrium concentration of cupferron is 0.5 g/L. A qualitative model is given, and the implications of this work for practical operations are presented

  19. Influence of attrition variables on iron ore flotation

    Directory of Open Access Journals (Sweden)

    Fabiana Fonseca Fortes

    Full Text Available Abstract The presence of slimes is harmful to the flotation process: the performance and consumption of reagents are negatively affected. Traditionally, the desliming stage has been responsible for removing slimes. However, depending on the porosity of the mineral particles, desliming may not be sufficient to maximize the concentration results. An attrition process before the desliming operation can improve the removal of slime, especially when slimes cover the surface and/or are confined to the cavities/pores of the mineral particles. Attrition is present in the flowcharts of the beneficiation process of phosphate and industrial sand (silica sand. Research has been undertaken for its application to produce pre-concentrates of zircon and iron ore. However, there is still little knowledge of the influence of the attrition variables on the beneficiation process of iron ore. This study presents a factorial design and analysis of the effects of these variables on the reverse flotation of iron ore. The standard of the experimental procedures for all tests included the attrition of pulp, under the conditions of dispersion, desliming and flotation. The parameter analysed (variable response was the metallurgical recovery in reverse flotation tests. The planning and analysis of the full factorial experiment indicated that with 95% reliability, the rotation speed of the attrition cell impeller was the main variable in the attrition process of the iron ore. The percentage of solid variables in the pulp and the time of the attrition, as well as their interactions, were not indicated to be significant.

  20. Analysis of phosphoric ore bacterial and eucaryal microbial diversity ...

    African Journals Online (AJOL)

    These findings provided new opportunities into phosphoric ore microbiology that could be useful in biological system removing waste gases generated from the phosphoric industry. Keywords: Microbial community, bacteria, archaea, eucarya, mining residue. African Journal of Biotechnology, Vol 13(30) 3023-3029 ...

  1. Studies of leaching of copper ores and flotation wastes

    International Nuclear Information System (INIS)

    Wawszczak, D.; Deptula, A.; Lada, W.; Smolinski, T.; Olczak, T.; Brykala, M.; Wojtowicz, P.; Rogowski, M.; Milkowska, M.; Chmielewski, A.G.

    2014-01-01

    In Poland, there are significant deposits of copper ores. During the copper extraction, large amounts of flotation wastes are produced. In the ores and flotation wastes many other important elements are present. The main goal of this work was analysis of uranium content and to elaborate procedures for recovery of U from these materials. Two types of ores and four types of waste were examined. It has been found that uranium content varies from 4.5 to 25 ppm. The other elements have also been determined in these materials: Cu (4-5 % in ores and 0.3-1.7 % in waste), Ag, Re, Mo, La, Ni, V, etc. For leaching, sulfuric acid and sodium carbonates of various concentrations (temperature, time) were used. The optimum conditions for leaching have been found. The concentration of uranium in the final solution was generally less than 25 μg/mL. The other elements are also present in the leaching solutions. Simultaneous liquid-liquid extraction of uranium with these elements from leaching solution is under study. In our opinion, only such combined procedure for the recovery of uranium together with the accompanying elements could be cost-effective. (author)

  2. Applicability of attrition of iron ore in floating

    International Nuclear Information System (INIS)

    Fortes, Fabiana Fonseca

    2010-01-01

    The aim of this study is to investigate the possibility to increase metal recovery in the flotation of iron ore with the implementation of a stage of scrubbing followed by dispersion. The minerals in question stems from two mines located in the western portion of the Iron Quadrangle and differ mainly with respect to the percentage of hematite and porous and the presence of aggregated masses. These characteristics were compared to those of other minerals that have succeeded with the adoption of this technique. Tests were conducted at bench scale scrubbing, desliming and concentration by flotation with the blend of ore from both mines. Were varied stirring time and pH. The chemical results of desliming and flotation products in the different conditions were compared. The presence of porous hematite is relevant in a mine, mainly due to the occurrence of earthy goethite, alumina carrier of the contaminant. The step desliming is insufficient for the removal of harmful sludge flotation. Laboratory experiments showed that the scrubbing of the pulp of iron ore of Minas de Capitao do Mato and Tamandua, agitated for 10 minutes followed by desliming amid scattered, promotes increased metal recovery by about 17% and increases the selectivity of 40 % compared to the results of the scrubbing and without dispersion. The scrubbing of hematite ore followed by desliming amid scattered can bring gains in improving the quality of pellet feed fine if deployed industrially. (author)

  3. Natural Ores as Oxygen Carriers in Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Hanjing; Siriwardane, Ranjani; Simonyi, Thomas; Poston, James

    2013-08-01

    Chemical looping combustion (CLC) is a combustion technology that utilizes oxygen from oxygen carriers (OC), such as metal oxides, instead of air to combust fuels. The use of natural minerals as oxygen carriers has advantages, such as lower cost and availability. Eight materials, based on copper or iron oxides, were selected for screening tests of CLC processes using coal and methane as fuels. Thermogravimetric experiments and bench-scale fixed-bed reactor tests were conducted to investigate the oxygen transfer capacity, reaction kinetics, and stability during cyclic reduction/oxidation reaction. Most natural minerals showed lower combustion capacity than pure CuO/Fe{sub 2}O{sub 3} due to low-concentrations of active oxide species in minerals. In coal CLC, chryscolla (Cu-based), magnetite, and limonite (Fe-based) demonstrated better reaction performances than other materials. The addition of steam improved the coal CLC performance when using natural ores because of the steam gasification of coal and the subsequent reaction of gaseous fuels with active oxide species in the natural ores. In methane CLC, chryscolla, hematite, and limonite demonstrated excellent reactivity and stability in 50-cycle thermogravimetric analysis tests. Fe{sub 2}O{sub 3}-based ores possess greater oxygen utilization but require an activation period before achieving full performance in methane CLC. Particle agglomeration issues associated with the application of natural ores in CLC processes were also studied by scanning electron microscopy (SEM).

  4. Rare earth elements materials production from apatite ores

    International Nuclear Information System (INIS)

    Anufrieva, A V; Buynovskiy, A S; Makaseev, Y N; Mazov, I N; Nefedov, R A; Sachkov, V I; Valkov, A V; Andrienko, O S; Stepanova, O B

    2016-01-01

    The paper deals with the study of processing apatite ores with nitric acid and extraction of the rare earth elements. The rare earth elements can be successfully separated and recovered by extraction from the nitrate- phosphate solution, being an tributyl phosphate as extraction agent. The developed scheme of the processing apatite concentrate provides obtaining rare earth concentrates with high qualitative characteristics. (paper)

  5. South China provenance of the lower-grade Penglai Group north of the Sulu UHP orogenic belt, eastern China. Evidence from detrital zircon ages and Nd-Hf isotopic composition

    International Nuclear Information System (INIS)

    Li Xianghui; Chen Fukun; Guo Jinghui; Xie Liewen; Siebel, Wolfgang

    2007-01-01

    The Dabie-Sulu ultrahigh-pressure orogenic belt resulted from the early Mesozoic collision of the North China block and South China block (comprising the Yangtze and the Cathaysia) and subsequent exhumation of the subducted South China continental slabs. This belt consists of tectonically juxtaposed rock units of different metamorphic grade. Provenance of the low-grade metamorphic terranes exposed along the northern part of the belt can offer useful information about the location of the boundary between these two continental blocks. This study reports detrital zircon ages and Nd-Hf isotopic composition of sedimentary rocks of the low-grade Penglai Group, situated north of the Sulu UHP terrane. Results show that detrital zircon grains mostly crystallized during Mesoproterozoic time, clustering at 1.7 Ga to 1.6 Ga and 1.2 Ga. Nd isotopic composition (T DM value) of the Penglai Group suggests that sedimentary sources are similar to average crustal material of the Yangtze block and mostly formed in Paleo- to Mesoproterozoic. Late Mesoproterozoic detrital zircons probably demonstrate the sedimentary material was derived from the boundary of the Yangtze and Cathaysia blocks, which was formed by the late Mesoproterozoic convergence. Absence of Neoproterozoic detrital zircons from the Penglai sediments probably suggests a late Mesoproterozoic to early Neoproterozoic deposition age (about 1.1 Ga to 0.8 Ga). The age and isotopic evidence implies that the Penglai Group originated from the South China block and probably was thrust onto the basement of the North China block during the early Mesozoic continental collision. (author)

  6. Comparative phylogeography of the Smilax hispida group (Smilacaceae) in eastern Asia and North America--implications for allopatric speciation, causes of diversity disparity, and origins of temperate elements in Mexico.

    Science.gov (United States)

    Zhao, Yunpeng; Qi, Zhechen; Ma, Weiwei; Dai, Qiongyan; Li, Pan; Cameron, Kenneth M; Lee, Joongku; Xiang, Qiu-Yun Jenny; Fu, Chengxin

    2013-08-01

    The Smilax hispida group (Smilacaceae) exhibits a discontinuous distribution in eastern Asia, eastern and western United States, and Mexico. A broad scale phylogeographic analysis was conducted for this group to evaluate the hypotheses of accelerated allopatric divergence in eastern Asia and a northern origin of the temperate elements in Mexico. Phylogeny was inferred using seven plastid and nuclear DNA sequences. Species delineation was assessed using genealogical sorting indices (GSI). Lineage divergence time, haplotype diversification rates, and ancestral distributions were estimated using Bayesian methods. Phylogeographic patterns in eastern Asia and North America were compared by analyzing 539 individuals from 64 populations to assess allopatric diversification. Results strongly supported delineation of six allopatric species, the origin of this group from a Mexican ancestor around 11.42mya, and Mexican origins of the temperate species in Mexico. Significant geographic structure of haplotypes was found in eastern Asia, and greater haplotype diversification rate was observed for the North American lineage. Our data support allopatric speciation in eastern Asia but do not find evidence of an elevated diversification rate. Greater species diversity of the study system in eastern Asia may be due to a longer evolutionary history. Our results do not support northern origins of the Mexican temperate species. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Rirang uranium ore processing: continuous solvent extraction of uranium from Rirang ore acid digestion solution

    International Nuclear Information System (INIS)

    Riza, F.; Nuri, H. L.; Waluya, S.; Subijanto, A.; Sarono, B.

    1998-01-01

    Separation of uranium from Rirang ore acid digestion solution by means of continuous solvent extraction using mixer-settlers has been studied and a mixture of 0.3 M D2EHPA and 0.075 M TOPO extracting agent and kerosene diluent is employed to recover and separate uranium from Th, RE, phosphate containing solution. The experiments have been conducted batch-wise and several parameters have been studied including the aqueous to organic phase ratio, A/O, the extraction and the stripping times, and the operation temperature. The optimum conditions for extraction have been found to be A/O = 2 ratio, five minute extraction time per stage at room temperature. The uranium recovery of 99.07% has been achieved at those conditions whilst U can be stripped from the organic phase by 85% H 3 PO 4 solution with an O/A = 1 for 5 minutes stripping time per stage, and in a there stage operation at room temperature yielding a 100% uranium recovery from the stripping process

  8. Novel Binders and Methods for Agglomeration of Ore

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-09-30

    Heap leaching is one of the methods being used to recover metal from low grade ore deposits. The main problem faced during heap leaching is the migration of fine grained particles through the heap, forming impermeable beds which result in poor solution flow. The poor solution flow leads to less contact between the leach solution and the ore, resulting in low recovery rates. Agglomeration of ore into coarse, porous masses prevents fine particles from migrating and clogging the spaces and channels between the larger ore particles. Currently, there is one facility in the United States which uses agglomeration. This operation agglomerates their ore using leach solution (raffinate), but is still experiencing undesirable metal recovery from the heaps due to agglomerate breakdown. The use of a binder, in addition to the leach solution, during agglomeration would help to produce stronger agglomerates that did not break down during processing. However, there are no known binders that will work satisfactorily in the acidic environment of a heap, at a reasonable cost. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. Increasing copper recovery in heap leaching by the use of binders and agglomeration would result in a significant decrease in the amount of energy consumed. Assuming that 70% of all the leaching heaps would convert to using agglomeration technology, as much as 1.64*10{sup 12} BTU per year would be able to be saved if a 25% increase in copper recovery was experienced, which is equivalent to saving approximately 18% of the energy currently being used in leaching heaps. For every week a leach cycle was decreased, a savings of as much as 1.23*10{sup 11} BTU per week would result. This project has identified several acid-resistant binders and agglomeration procedures. These binders and experimental procedures will be able to be used for use in improving the energy efficiency of

  9. Geological-economic analysis on the exploration of backup resources for depleted mines in Lujing uranium ore-field, central-southern China

    International Nuclear Information System (INIS)

    Li Deping; Wang Zhicheng; Fan Shaoyun

    2006-01-01

    With the geological-economic evaluation program for pithead heap-leaching mining uranium deposits developed by the authors and the data of column-leaching tests and the geological reserve, the geological-economic evaluation is made to the residual geological reserves of both Lujing and Huangfengling deposit, and the geological reserves of Yangjiaonao deposit of the depleted mines in Lujing uranium ore-field, central-southern China. The results of static analysis on these reserves show that the residual geological reserves of both Lujing and Huangfengling deposit belong to sub-profitable type, but the ones of Yangjiaonao deposit is profitable with 26.56% tax-before profit. 1 tU profitable type of ore from Yangjiaonao deposit can use 2.40-3.79 tU subprofitable type of ores from Lujing and Huangfengling deposit. In order to solving the problem on scarcity of backup resources of the depleted mines in Lujing uranium ore-field and using the existing sub-profitable type of geological reserves, it is suggested that the high grade of profitable type of deposits should be explored around the exhausting mines so that the production of the mines could be profitable by the pithead heap-leaching mining method with arrangement groups of both sub-profitable and profitable type of ores. (authors)

  10. The geochemical characteristics of alkali metasomatic ore and its ore-forming significance at Zoujiashan deposit, Xiangshan uranium field

    International Nuclear Information System (INIS)

    Wang Yun; Hu Baoqun; Sun Zhanxue; Li Xueli; Guo Guolin; Rao Minghui

    2012-01-01

    Alkaline metasomatites are widely distributed in Zoujiashan uranium deposit and have close relation with uranium mineralization. Based on the study of field geological survey, petrographic methods, element chemical analysis and EPMA, etc, the alteration in alkaline metasomatic ore was found in the order of sodium metasomatism, potassium metasomatism and silica metasomatism. The alkaline hydrothermal fluid of mineralization is rich in Na at first and then rich in K, and quite similar in other chemical composition, but the K rich one is more favourite for the metallization. Compared with the normal porphyroclastic lava, the alkaline metasomatic ores in lower in SiO 2 , but higher in K 2 O or Na 2 O, Al 2 O 3 , Fe 2 O 3 , MgO, P 2 O 5 , CaO and U, Th, Zr, Hf, Sm, Ti, REE. Compared with potassium metasomatic ore, the sodium metasomatic ore is with high ΣLREE/ΣHREE ratio and lower Rb and REE. Because alkaline metasomatism is beneficial to release uranium from accessory mineral and bring out uranium from rocks, therefore it is very important to the migration and precipitation of uranium. (authors)

  11. Uranium extraction from ores with salicylic acid; I - uranium extraction from input phosphate ore of Abu Zaabal phosphate plant, Egypt

    International Nuclear Information System (INIS)

    Hussein, E.M.

    1997-01-01

    Salicylic acid has been tested (for environmental importance) to extract U from input phosphate ore of Abu-Zaabal phosphate plant, Egypt prior to its processing for production of phosphatic fertilizers. Uranyl ion forms with this acid three stable complexes; namely [UO 2 Sal] degree, [U O 2 SaL 2 ] 2- and UO 2 SaL-3] 4- depending on the total uranyl and salicylic acid concentrations and their ratios. Study of relevant extraction factors revealed however that, the extraction process is controlled by the amount of salicylic acid used, alcohol/aqueous ratio, solid/liquid ratio and time of agitation. The obtained results showed that uranium is selectively leached by the application of such a leaching reagent. In order to recover U from the obtained pregnant leach liquor, the latter is adjusted by ammonia to PH 5-6.5, where the crystalline pp t of N H 4 [UO 2 SaL 3 ] 4 H 2 O has formed. This precipitation has been carried out after concentrating the obtained pregnant leach liquor by its recycle for U extraction from new ore batches. The precipitated ammonium uranyl tri salicylate is calcined at 500 degree C for obtaining pure orange yellow trioxide (UO 3 ) powder. On the basis of one ton ore treatment, an economic flowsheet for U recover y from the study ore material has been suggested

  12. Methods of evaluating ore processing and effluent treatment for Cigar Lake ore at the Rabbit Lake Mill

    International Nuclear Information System (INIS)

    Edwards, C.R.

    2002-01-01

    Cigar Lake is the second-largest, high grade uranium orebody in the world. Mineable reserves for Cigar Lake Phase 1 are estimated at 191 million pounds U 3 O 8 with a grade of 25.6% U 3 O 8 . Subject to regulatory approval, Cameco intends to process the majority of ore from Cigar Lake in the Rabbit Lake mill. Cameco initiated a programme to study the processing of Cigar Lake ore and the treatment of the resulting waste streams. Laboratory and follow-up pilot scale ore leaching tests with Cigar Lake ore samples were performed. Tailings and effluents were generated from the products of the pilot scale leach tests. Mill process tailings were blended with ground waste rock. Using these materials, geotechnical and geochemical properties, including long term tailings pore water characteristics, will be evaluated. In addition, proposed changes to the mill waste treatment operations were developed to deal with increased levels of arsenic and radium in the waste streams. This paper describes the methods and techniques Cameco used in this programme. (author)

  13. Impact Of Low Grade Uranium Ores On The Echo System and the Workers of Phosphate Industry

    International Nuclear Information System (INIS)

    Anwar, S.M.

    1999-01-01

    The present study aims to investigate the influence of uranium present in phosphate rocks as an environmental factor in the ccho system and on the workers of Abu-Zaabal Phosphate Company subjected to the inhalation of big quantities of rock phosphate dust during the benefication of the ore and the production of the fertilizers. Besides. extra amount of uranium reach the workers also through two path ways.The first is direct through eating contaminated planted grown in the near by area.The second is indirect through eating animals fed with contaminated plants. The uranium content is estimated in the soil samples at different depths, water (irrigation and drainage), air samples and plant samples (shoot and root) in Berseem from the four directions, urine samples from twenty workers in charge of the processing of phosphate compared to twenty volunteers far from the contaminated area.The results showed an elevated values for phosphorus and uranium in the air, water. soil and plant (Berseem) around Abu Zaabal Factory and extending to about 2 km from all directions. Urine may be considered as a biological indicator medium for the uptake of uranium in uranium miners and the workers in charge of ore processing and can represent the major route of excretion for the absorbed metal. Significant differences were shown between the uranium level in the urine of workers group and the control group

  14. Fundamentals of fast reduction of ultrafine iron ore at low temperature

    Institute of Scientific and Technical Information of China (English)

    Pei Zhao; Peimin Guo

    2008-01-01

    Fundamentals on the fast reduction of ultrafine iron ore at low temperature, including characterization of ultrafine ore, de- oxidation thermodynamics of stored-energy ultrafine ore, kinetics of iron ore deoxidation, and deoxidation mechanism, etc., and a new ironmaking process are presented in this article. Ultrafine ore concentrate with a high amount of stored energy can be produced by mechanical milling, and can be dcoxidated fast below 700℃ by either the coal-based or gas-based process. This novel process has some advantages over others: high productivity, low energy consumption, and environmental friendliness.

  15. Characteristics of sandstone-type uranium mineralization and ore-controlling factors in Wukurqi ore district at southern margin of Yili basin, Xinjiang

    International Nuclear Information System (INIS)

    Li Xigen

    2002-01-01

    With the theories of hydrogenic uranium deposit in the nineties, Wukurqi ore district as a new area was found by the regional prediction and prospecting. Specially, through uranium ore prospecting of about three years, certain prospective reserves are generally controlled in the area. These reserves are hosted in V cyclothem of Middle-Lower Jurassic series, and some prospective reserves are hosted in II and VII cyclothems. By analyzing and summarizing characteristics of sandstone-type uranium mineralization and its ore-controlling factors in Wukurqi ore district, the author provides a foundation for developing further prospecting in this area

  16. Development of the Method of Bacterial Leaching of Metals out of Low-Grade Ores, Rocks, and Industrial Wastes Using Neutron Activation Analysis

    CERN Document Server

    Tsertsvadze, L A; Petriashvili, Sh G; Chutkerashvili, D G; Kirkesali, E I; Frontasyeva, M V; Pavlov, S S; Gundorina, S F

    2001-01-01

    The results of preliminary investigations aimed at the development of an economical and easy to apply technique of bacterial leaching of rare and valuable metals out of low-grade ores, complex composition ores, rocks, and industrial wastes in Georgia are discussed. The main groups of microbiological community of the peat suspension used in the experiments of bacterial leaching are investigated and the activity of particular microorganisms in the leaching of probes with different mineral compositions is assessed. The element composition of the primary and processed samples was investigated by the epithermal neutron activation analysis method and the enrichment/subtraction level is estimated for various elements. The efficiency of the developed technique to purify wastes, extract some scrace metals, and enrich ores or rocks in some elements, e.g. Au, U, Th, Cs, Sr, Rb, Sc, Zr, Hf, Ta, Gd, Er, Lu, Ce, etc., is demonstrated.

  17. Development of Technology for Enrichment of Silver Containing Ores

    Science.gov (United States)

    Shekiladze, Asmati; Kavtelashvili, Otari; Bagnashvili, Mamuka

    2016-10-01

    The progress of Georgian economics is substantially associated with a development of new deposits of mineral resources. Among them is the David-Gareji deposit where at present the intensive searching geological works are performed. The work goal involves the elaboration of the technology for processing of silver-containing quartz-barite ores. Without its development the mining of more valuable gold-polymetallic ores is impossible. Because of ore complexity silver and barite are considered in a common technological aspect. The investigations were carried out on the representative samples of quartz-barite ores containing 78-88 g/ton of silver and 27-29 % of silver is a nugget in the form of the simple sulphides and chlorides. The ore is characterized by fine coalescence of barite and ore-generating minerals. Non-ferrous metals haven't any industrial value because of their very low content. Therefore, for the processing of the ores under study the direct selective scheme of flotation enrichment was chosen and the formula of optimal reagent regime was elaborated. Potassium xanthogenate is used as a collector for flotation of silver minerals and pine oil- as a foaming agent. The effect of the pulp - pH and medium temperature on silver flotation was studied. It was established that the silver is actively floats in neutral medium. For barite flotation the various collectors were tested: sulfidezid cotton oil-soap stock, soaps of fatty acids and alkyl sulphates of C12 - C16 row, among the “Baritol” is the most efficient one. Depression of the barren rock was carried out by liquid glass in alkaline medium. The effect of pulp pH on barite flotation has been investigated. The best results were obtained at pH=8.5. The increase of the pulp alkalinity has no essential effect on the indexes of the barite enrichment. Conditional concentrate of the barite is obtained by two fold purification of the main flotation concentrate by the addition of the liquid glass to the re

  18. Trace and rare earth elements fractionation in volcanic- and sediment-hosted Mn ores: a study case of Sardinia (western Italy).

    Science.gov (United States)

    Sinisi, Rosa

    2015-04-01

    It is widely accepted that, regardless of the geological environment (continental, marine or hydrothermal), the occurrences of clay minerals and/or mineral phases with clay-type crystal structure (as zeolites and Mn-oxides), play a key role in the trace elements and REEs uptake processes. The REE resources are produced mostly from ion-adsorption type REE deposits of southern China that are formed by weathering of granitic rocks and subsequent chemical adsorption of REE on clay minerals. A significant group of minerals with a high metal uptake capacity is represented by Mn oxides. Their "tunnel" structure, in fact, allows both the absorption (inside the minerals) and adsorption (outside the minerals) of cations and anions producing metal accumulations with economic and environmental significance. However, the ores, mainly that forming within sedimentary environment, often have impurities due to presence of minerals unrelated to mineralization. These minerals can significantly alter the compositional features of the ores and suggest misleading conclusions. In Sardinia (Italy, western Mediterranean), Mn-oxide mineralizations occur and recently their origin has been discussed and identified (Sinisi et al. 2012). In this study the mineralogical and chemical compositions of the Sardinian sediment-hosted and volcanic-hosted Mn-ore are exhibit exploring the possibility that they can represent exploitable trace and REE mineralizations. High contents of metals characterize these Mn deposits. Besides some trace elements (Ni, Cr, Zn, Cu, As, Pb, and U) that commonly typify the Mn oxi-hydroxide ores, all rare earth elements showed high concentrations in the Sardinian deposits, comparable to those of the main actually exploited REE sinks. For this reason, a simple statistical data treatment (R-mode Factor Analysis) was performed on fifteen and nineteen samples of sediment-hosted and volcanic-hosted Mn ore respectively, in order to identify both the mineral phases trapping trace

  19. Industrial mining forecasts for the North East of Spain

    International Nuclear Information System (INIS)

    Ramirez, A.

    1993-01-01

    The North-Eastern part of Spain shows a variety of lithologies morphologies and structures. A lot of different ores can be found but deposit reserves are very scarce and widespread. Metallic mines were important in the past but now are spent. All types of coal are present but deposits are small and exploitation has reduced very much the reserves. Only uranium and lignite are significant materials but the current trends of international prices makes not north their extraction. Gas and Petroleum are being extracted and their well known deposits will keep activity as nowadays. The paper makes and additional review on other non-energetic ores like special clays, sodium an potassium salts, sodium sulphates, gypsum and other

  20. Use of tail less amphibians in system of biomonitoring for estimation of influencing of wastes of enterprises on processing of uranium ore on zoocenosis

    International Nuclear Information System (INIS)

    Misyura, A.N.; Marchenkovskaya, A.A.

    2006-01-01

    The researches of influencing of wastes of enterprises on processing of uranium ore showed that by the sole type of amphibious, dwelling in sewage of amphibians - lake frog. Individuals of senior age groups of this type of amphibians partly oneself adapted to influencing of pollutants sewage due to the change of physiology-biochemical parameters of the organs, actively participating in metabolism. (authors)

  1. Molecular assessment of Hepatozoon (Apicomplexa: Adeleorina) infections in wild canids and rodents from north Africa, with implications for transmission dynamics across taxonomic groups.

    Science.gov (United States)

    Maia, João P; Alvares, Francisco; Boratyński, Zbyszek; Brito, José C; Leite, João V; Harris, D James

    2014-10-01

    Parasites play a major role in ecosystems, and understanding of host-parasite interactions is important for predicting parasite transmission dynamics and epidemiology. However, there is still a lack of knowledge about the distribution, diversity, and impact of parasites in wildlife, especially from remote areas. Hepatozoon is a genus of apicomplexan parasites that is transmitted by ingestion of infected arthropod vectors. However, alternative modes of transmission have been identified such as trophic transmission. Using the 18S rRNA gene as a marker, we provide an assessment of Hepatozoon prevalence in six wild canid and two rodent species collected between 2003 and 2012 from remote areas in North Africa. By combining this with other predator-prey systems in a phylogenetic framework, we investigate Hepatozoon transmission dynamics in distinct host taxa. Prevalence was high overall among host species (African jerboa Jaculus jaculus [17/47, 36%], greater Egyptian jerboa Jaculus orientalis [5/7, 71%], side-striped jackal Canis adustus [1/2, 50%], golden jackal Canis aureus [6/32, 18%], pale fox Vulpes pallida [14/28, 50%], Rüppell's fox Vulpes rueppellii [6/11, 55%], red fox Vulpes vulpes [8/16, 50%], and fennec fox Vulpes zerda [7/11, 42%]). Phylogenetic analysis showed further evidence of occasional transmission of Hepatozoon lineages from prey to canid predators, which seems to occur less frequently than in other predator-prey systems such as between snakes and lizards. Due to the complex nature of the Hepatozoon lifecycle (heteroxenous and vector-borne), future studies on these wild host species need to clarify the dynamics of alternative modes of Hepatozoon transmission and identify reservoir and definitive hosts in natural populations. We also detected putative Babesia spp. (Apicomplexa: Piroplasmida) infections in two canid species from this region, V. pallida (1/28) and V. zerda (1/11).

  2. Phase I trial of erlotinib with radiation therapy in patients with glioblastoma multiforme: Results of North Central Cancer Treatment Group protocol N0177

    International Nuclear Information System (INIS)

    Krishnan, Sunil; Brown, Paul D.; Ballman, Karla V.; Fiveash, John B.; Uhm, Joon H.; Giannini, Caterina; Jaeckle, Kurt A.; Geoffroy, Francois J.; Nabors, L. Burt; Buckner, Jan C.

    2006-01-01

    Purpose: To evaluate the toxicity and maximum tolerated dose (MTD) of erlotinib plus radiation therapy (RT) in patients with glioblastoma multiforme (GBM) in a multicenter phase I trial. Methods and Materials: Patients were stratified on the basis of the use of enzyme-inducing anticonvulsants (EIACs). After resection or biopsy, patients were treated with erlotinib for 1 week before concurrent erlotinib and 6 weeks (60 Gy) of RT and maintained on erlotinib until progression. The erlotinib dose was escalated in cohorts of 3 starting at 100 mg/day. Results: Twenty patients were enrolled and 19 were evaluable for the MTD and efficacy endpoints. Of these patients, 14 were males and 5 were females, with a median age of 54 years. Seven had undergone biopsy only, 5 had subtotal resections, and 7 had gross total resections. The highest dose level was 150 mg/day erlotinib for patients not on EIACs (Group 1) and 200 mg/day for patients on EIACs (Group 2). MTD was not reached in either group. In Group 1 at 100 mg (n = 6) and at 150 mg (n = 4), only 1 dose-limiting toxicity (DLT) occurred (stomatitis at 100 mg). No DLTs have occurred in Group 2 at 100 mg (n = 3), 150 mg (n = 3), and 200 mg (n = 3). With a median follow-up of 52 weeks, progression was documented in 16 patients and 13 deaths occurred. Median time to progression was 26 weeks, and median survival was 55 weeks. Conclusion: Toxicity is acceptable at the current doses of erlotinib plus RT. The study was modified to include concurrent and adjuvant temozolomide, and accrual is in progress

  3. The genesis of the base metal ore deposit from Herja

    Directory of Open Access Journals (Sweden)

    Gheorghe Damian

    2003-04-01

    Full Text Available The Herja ore deposit is one of the most known of the Baia Mare Neogene metallogenetic district and is associated with a complex stock of Pannonian age. The hydrothermal alterations associated with the mineralizations are represented by: the propylitization, the argillization, the phyllic and potassic alteration. The monoascenedant character of the mineralizations is predominant. The magmatic intrusions have been sequential placed and have represented the heat, metals and hydrothermal solutions source. In the first stages of mineralization the hydrothermal solutions contain predominantly magmatic water and in the final stages the water is of connate and meteoric origin. According to the structural magmatic control, to the mineralogical composition and to the hydrothermal alterations, the Herja ore deposits are of a low sulphidation epithermal systems type.

  4. Magmatic gases in fluid inclusions from hydrothermal ore deposits

    Energy Technology Data Exchange (ETDEWEB)

    Graney, J.; Kesler, S. (University of Michigan, MI (United States))

    1992-08-31

    In this study, magmatic gases in fluid inclusions from hydrothermal ore deposits have been analyzed. The gas composition of fluid inclusions from a wide range of extinct hydrothermal systems as represented by different ore deposit types was determined using a quadrupole mass spectrometer. Most samples used for analysis consisted of transparent quartz, although barite, jasperoid, opal, sphalerite, pyrite, chalcopyrite, and bornite were also analyzed. H2O was the dominant volatile component in fluid inclusions, and composed 95-99 mole percent of the inclusion fluid. CO2 comprised most of the remaining volatile component and the other gases were generally present in amounts smaller than 0.1 mole percent. Analysis from porphyry and acid-sulfate deposits, in which magmatic gas contributions are considered to be largest, plotted closest to the fumarolic gas compositions. These inclusion fluid volatile component comparisons have shown that there are systematic differences in inclusion fluids from different hydrothermal systems. 9 refs., 3 figs.

  5. Applying Four Different Risk Models in Local Ore Selection

    International Nuclear Information System (INIS)

    Richmond, Andrew

    2002-01-01

    Given the uncertainty in grade at a mine location, a financially risk-averse decision-maker may prefer to incorporate this uncertainty into the ore selection process. A FORTRAN program risksel is presented to calculate local risk-adjusted optimal ore selections using a negative exponential utility function and three dominance models: mean-variance, mean-downside risk, and stochastic dominance. All four methods are demonstrated in a grade control environment. In the case study, optimal selections range with the magnitude of financial risk that a decision-maker is prepared to accept. Except for the stochastic dominance method, the risk models reassign material from higher cost to lower cost processing options as the aversion to financial risk increases. The stochastic dominance model usually was unable to determine the optimal local selection

  6. Treatment of waste water from uranium ore preparation

    International Nuclear Information System (INIS)

    Klicka, V.; Mitas, J.; Vacek, J.

    1976-01-01

    An improved closed-loop process is described for treating waste water resulting from chemical extraction of uranium from ore. The water is evaporated to form a concentrated solution and is then subjected to crystallization of the least soluble salt component thereof via further evaporation, or cooling or simultaneous cooling and a partial vacuum. The crystallized component is then separated from the mother liquor, whereupon the latter is fed back after removal of residual uranium therefrom to the extraction installation to replace the acids used therein. Additionally, the pure condensate produced during evaporation of the waste waters is employed as a replacement for the fresh water employed in processing of the ore. 6 claims, 2 figures

  7. South African gold and uranium ore mining in 1976

    International Nuclear Information System (INIS)

    Hentrich, W.

    1977-01-01

    1976 was a difficult year for the South African gold and uranium ore mining industry, the region of Witwatersrand (Transvaal province) producing some 75% of all the gold mined in the western world besides being an important producer of uranium oxide. Despite the gold production, declining since 1971, not showing a downward tendency anymore as far as the quantity was concerned, the economic result, however, deteriorated as a consequence of continuously falling gold prices, but also on account of the inflationary rise in wages and the prices for energy and materials. Much higher prices for uranium oxide, which some mines produce as interim products from the 'degolded' slurries of their gold ore leaching plants, improved the economic overall result only to a small degree. (orig.) [de

  8. Analytical procedure for the radiometric determination of uranium in ores

    International Nuclear Information System (INIS)

    Bone, S.J.; Porritt, R.E.J.

    1976-06-01

    Two methods are described for the non-destructive determination of uranium in ores: a beta-gamma measuring method and a gamma-spectrometrical one. The first has the advantage that the analysis is not influenced by a radioactive unbalance in the sample (say by loss of radium as a result of chemical decomposition of the ores) and that it can be carried out with comparitively simple apparative expenditure. It is, however, relatively inaccurate (+-25%) and should only be used as a surveying method. The gamma-spectrometrical analysis (accuracy about +-10%) gives information about an unbalance present between U 238 and Ra 226 and thus enables an appropriate correction to be made. A thorium contribution with its decay products can also be corrected. (RB) [de

  9. Rirang Uranium Ore Processing System Design: Agitated Digester

    International Nuclear Information System (INIS)

    Erni, R.A.; Susilaningtyas

    1996-01-01

    A closed tank digester equipped with a pitched blades turbine agitator has been designed to facilities Rirang uranium ore dissolution using concentrated sulphuric acid at high temperature. The digester was designed to accommodate the digestion of 6 kg of-65 mesh ore at 200 o C, acid resistant material (SS-3 16). It has the dimension of 33 cm high, 22 cm diameter, and elliptical bottom and height of 4 cm. Moreover, the dimension of the 4 blades agitator is as follows: 8 cm long, 1,6 cm blades width. The distance between the blades and digester required 0, 007 Hp for a 500 rpm agitation speed and + 24. 103 kcal energy equipment for heating. Digestion experiment using the agitated digester yielded data that are in good agreement with laboratory scale experiment

  10. Nickel Ore Dispersion Evaluation and Consequences in Flotation Process

    Science.gov (United States)

    de São José, Fábio; Imbelloni, Alaine Moreira; Nogueira, Francielle Câmara; Pereira, Carlos Alberto

    2016-04-01

    Nickel ore dispersion before flotation using different reagents was investigated on a bench scale to improve metallurgical recovery and selectivity. The nickel ore had a content of 0.8 pct nickel and 14.5 pct MgO. A positive linear correlation between MgO and Ni was found. Carboxy methyl cellulose, both pure and combined with Na2CO3, was the best dispersant used. The most efficient collector was potassium amyl xanthate combined with mercaptobenzothiazole, and the addition of xanthate was decisive for this good result because it is normally more stable in the pH range used in the tests. A pH change from 7 to 9 resulted in a metal recovery increase of 49.3 pct, together with an increase of 6.25 pct of MgO in the concentrate.

  11. Flotation study on scheelite ore of chitral khyber pakhtoonkhwa, pakistan

    International Nuclear Information System (INIS)

    Bhatti, M.A.; Kazmi, K.R.; Mehmood, R.; Akram, A.

    2014-01-01

    The beneficiation of a siliceous scheelite ore of Chitral, Khyber Pakhtoonkhwa, Pakistan, was investigated by flotation process to determine the optimum conditions for obtaining maximum grade and recovery of the scheelite concentrate. The variables studied were including pH and pulp density maintained during conditioning, type and quantity of reagents added, conditioning time and froth collecting time. The results achieved were plotted against the grade and recovery of the rougher concentrate. Several methods of cleaning rougher concentrate were attempted. An ore initially containing 0.34% WO/sub 3/ was upgraded into a final concentrate assaying 64.66% WO/sub 3/ with 70.36% recovery. The tungsten concentrate obtained meets the specifications required to produce ferrotungsten and tungsten chemicals. (author)

  12. DH-1a: a certified uranium-thorium reference ore

    International Nuclear Information System (INIS)

    Steger, H.F.; Bowman, W.S.; Zechanowitsch, G.

    1981-09-01

    A 122-kg sample of uranium-thorium ore, DH-1a, from Elliot Lake, Ontario, was prepared as a compositional reference material to replace the similar certified ore, DH-1. DH-1a was ground to minus 74μm, blended in one lot, and bottled in 200 g units. The homogeneity of DH-1a with respect to uranium was confirmed using the volumetric umpire method. The recommended value for uranium is based on the data from the confirmation of homogeneity. For thorium, twelve laboratories provided results in a free choice analytical program. A statistical analysis of the data gave a recommended value of 0.263 percent for uranium and 0.091 percent for thorium

  13. Chlorine-assisted leaching of Key Lake uranium ore

    International Nuclear Information System (INIS)

    Haque, K.E.

    1981-04-01

    Bench-scale chlorine-assisted leach tests were conducted on the Key Lake uranium ore. Leach tests conducted at 80 0 C on a slurry containing 50% solids during 10 hours of agitation gave the maximum extraction of uranium - 96% and radium-226 - 91%. Chlorine was added at 23.0 Kg Cl 2 /tonne of ore to maintain the leach slurry pH in the range of 1.5-1.0. To obtain residue almost free of radionuclides, hydrochloric acid leaches were conducted on the first stage leach residues. The second stage leach residue still was found to contain uranium - 0.0076% and radium-226 - 200 pCi/g of solids

  14. The ecological condition and diseases malignant new formation at the population of north region Kazakhstan

    International Nuclear Information System (INIS)

    Makishev, A.K.; Rakhimbekov, M.O.; Zhakipbaev, K.A.; Malaniya, Z.Sh.; Zhagiparov, M.K.; Kusainov, K.Z.

    2003-01-01

    Growing diseases malignant formation by many countries of the world, including Kazakhstan, relatedness with deterioration ecological state. Broadly geological researches, development of pits (coal, gold-bearing, and uranium ore) in north region of the Republic renders negative influence on the picture of population health, that bring increasing level of diseases mortality

  15. Effect of moisture content on the flowability of crushed ores

    OpenAIRE

    Cabrejos Francisco

    2017-01-01

    In many mining and industrial processes where large quantities of non-degrading bulk materials such as crushed ores are handled, silos, hoppers, stockpiles and chutes are widely used because they are economical and reliable (if properly designed and operated). However, they are not free of trouble and may experience flow problems such as arching, ratholing, erratic flow, limited storage capacity, limited discharge flow rate, caking, segregation and/or flooding. Moisture content and fine parti...

  16. Underground bioleaching: extracting from low-grade ore

    International Nuclear Information System (INIS)

    McCready, R.G.L.

    1986-01-01

    In 1984, Denison Mines began a research and demonstration project on the engineering aspects of bacterial leaching of low-grade uranium ore at Elliot Lake. The leaching solution was acidic mine water enriched in bacterial nutrients and innoculated with Thiobacillus ferrooxidans. Leaching of one stope was found to be impeded by fungi of the genus penicillium. Although fungal growth on leaching stopes must be prevented, research is proceeding on the potential use of the fungi to concentrate uranium from bioleaching solutions

  17. Bacteria heap leaching test of a uranium ore

    International Nuclear Information System (INIS)

    Liu Hui; Liu Jinhui; Wu Weirong; Han Wei

    2008-01-01

    Column bioleaching test of a uranium ore was carried out. The optimum acidity, spraying intensity, spray-pause time ratio were determined. The potential, Fe and U concentrations in the leaching process were investigated. The effect of bacteria column leaching was compared with that of acid column leaching. The results show that bacteria column leaching can shorten leaching cycle, and the leaching rate of uranium increases by 9.7%. (authors)

  18. Popov form computation for matrices of Ore polynomials

    DEFF Research Database (Denmark)

    Khochtali, Mohamed; Né Nielsen, Johan Rosenkilde; Storjohann, Arne

    2017-01-01

    Let F[∂; s, d] be a ring of Ore polynomials over a field. We give a new deterministic algorithm for computing the Popov form P of a non-singular matrix A ∈ F[∂; s, d]n×n. Our main focus is to ensure controlled growth in the size of coefficients from F in the case F = k(z), and even k = Q. Our...

  19. An Effective Belt Conveyor for Underground Ore Transportation Systems

    Science.gov (United States)

    Krol, Robert; Kawalec, Witold; Gladysiewicz, Lech

    2017-12-01

    Raw material transportation generates a substantial share of costs in the mining industry. Mining companies are therefore determined to improve the effectiveness of their transportation system, focusing on solutions that increase both its energy efficiency and reliability while keeping maintenance costs low. In the underground copper ore operations in Poland’s KGHM mines vast and complex belt conveyor systems have been used for horizontal haulage of the run-of-mine ore from mining departments to shafts. Basing upon a long-time experience in the field of analysing, testing, designing and computing of belt conveyor equipment with regard to specific operational conditions, the improvements to the standard design of an underground belt conveyor for ore transportation have been proposed. As the key elements of a belt conveyor, the energy-efficient conveyor belt and optimised carrying idlers have been developed for the new generation of underground conveyors. The proposed solutions were tested individually on the specially constructed test stands in the laboratory and in the experimental belt conveyor that was built up with the use of prototype parts and commissioned for the regular ore haulage in a mining department in the KGHM underground mine “Lubin”. Its work was monitored and the recorded operational parameters (loadings, stresses and strains, energy dissipation, belt tracking) were compared with those previously collected on a reference (standard) conveyor. These in-situ measurements have proved that the proposed solutions will return with significant energy savings and lower maintenance costs. Calculations made on the basis of measurement results in the specialized belt conveyor designing software allow to estimate the possible savings if the modernized conveyors supersede the standard ones in a large belt conveying system.

  20. Mining, ore preparation and ferroniobium production at CBMM

    International Nuclear Information System (INIS)

    deSouza Paraiso, O.; deFuccio, R.

    1984-01-01

    The paper presents a chronology of the history and development of the Araxa carbonatite complex with respect to the production of niobium products. Mining and geology are described, including the background on methods used for defining reserves. The ore treatment technology and material flow patterns are described in detail, together with descriptions on impurity removal by calcination and leaching. Ferroniobium is produced aluminothermically in simple, yet massive, reactors and details of the process are given

  1. Analytic study of organic matters in Lodeve uranium ore

    International Nuclear Information System (INIS)

    Campuzano, E.J.

    1981-01-01

    Exploitation of uranium in the Permian basin of Lodeve is difficult because of simultaneous extraction of organic matters which are found, in small proportion, in ammonium diuranate and a supplementary purification is required. Available information on natural organic matters are briefly reviewed. Natural organic matters contained in the Lodeve uranium ore processing fluid is separated and fractionated. Physicochemical properties of ligands in each fraction are studied. The existence of bonds between these ligands and dissolved uranium is experimentally demonstrated [fr

  2. Determination of U (Ⅵ) content in uranium molybdenum ores

    International Nuclear Information System (INIS)

    Wang Haisheng; Ding Hongfang

    2014-01-01

    Potentionmetric titration is established to determine U (Ⅵ) in uranium molybdenum ores. In the closed condition, U (Ⅵ) is leached by carbonate solution. U (Ⅵ) is reduced to U (Ⅳ) by ferrous sulfate in phosphoric acid. The exess ferrous sulfate is oxidized by sodium nitrite. urea decompose the exess sodium nitrite. U (Ⅳ) is titrated by ammonium metavanadate standard solution with potentionmetric titration. The precision is better than 5%, The recovery rate is 97.2%∼101.9%. (authors)

  3. A study of VMS ore deposits by the proton microprobe

    International Nuclear Information System (INIS)

    Huston, D.L.; Large, R.R.; Bottril, R.S.; Sie, S.H.; Ryan, C.G.

    1991-01-01

    As part of studies into the mineralogical distribution of gold in volcanogenic massive sulfide (VMS) ore deposits PIXE analysis by the proton microprobe has been used to determine the gold content of pyrite and arsenopyrite from the Rosebery, Mt. Chalmers and Mt. Lyell deposits. In addition, the concentrations of Co, Ni, Cu, Zn, As, Sr, Y, Zr, Mo, Ag, Sb, Te, Au, Tl, Pb and Bi were also determined. 4 refs., 1 tab

  4. Geostatistics applied to estimation of uranium bearing ore reserves

    International Nuclear Information System (INIS)

    Urbina Galan, L.I.

    1982-01-01

    A computer assisted method for assessing uranium-bearing ore deposit reserves is analyzed. Determinations of quality-thickness, namely quality by thickness calculations of mineralization, were obtained by means of a mathematical method known as the theory of rational variables for each drill-hole layer. Geostatistical results were derived based on a Fortrand computer program on a DEC 20/40 system. (author)

  5. Thirty years of uranium ore processing in Spain

    International Nuclear Information System (INIS)

    Josa, J.M.

    1982-01-01

    Spanish background in the uranium ore processing includes ores from pegmatitic type deposits, vein deposits, sandstone, enrichments in metamorphic rocks, radioactive coals and non-conventional sources of uranium, such as wet phosphoric acid or copper liquors. Some tests have also done in order to recover uranium from very low grade paleozoic quartzites. We have also been involved in by-products recovery (copper) from uranium ores. The technologies that have been used are: physical concentration, combustion and roasting, conventional alkaline or acid methods, pressure, heap and bacteria leaching. Special attention was paid to recover uranium from the pregnant liquors and to develop suited equipment for it; solvent extraction and continuous ion exchange equipment was carefully studied. We have been involved in commercial size (500-3000 t/d) mills, but we have also developed transportable and reussable modular plants specially designed and suited to recover uranium from small and isolated deposits. In both cases the reduction of the environmental impact was taken in account. Spanish experience also includes nuclear purification aspects in order to get uranium nuclear compounds (ADU, UO 2 , UF 4 and UF 6 ). Wet (nitric-TBP) and dry (Fluid-bed) methods have been used. The best of these 30 years of experience in studies and in industrial practice, together with our new developments towards the future, could become in a good contribution for the medium size countries which are going to develop its own uranium industry. The way for these countries could be easier if they know what is valuable and what must be avoid in the uranium ore processing development. In this aim the whole paper was thought and written. (author)

  6. THE SOLUBILITY OF MILAS BAUXITE ORE IN SULPHURIC ACI

    Directory of Open Access Journals (Sweden)

    Mustafa GULFEN

    2001-06-01

    Full Text Available The effects of calcination conditions,sulphuric acid concentrations and dissolvingtemperature and period as parameters to thesolubility of the bauxite ore from Gobekdagı reservesin Mugla-Milas region were investigated. The bauxitesamples were calcined in different periods at differenttemperatures. Then the solubility of the calcinedbauxite samples in sulphuric acid solution wasexamined. Dissolving activation energy (Ea wascalculated using the optimum kinetics equation andthe results obtained from the solubility studiesexamined dissolving temperatures and periods

  7. The separation and determination of trace elements in iron ore

    International Nuclear Information System (INIS)

    Jones, E.A.

    1977-01-01

    The separation, concentration, and determination of trace elements in iron ores are described. After the sample has been dissolved, the iron is separated by liquid-liquid extraction with a liquid cation-exchanger, di-(2-ethylhexyl) phosphoric acid. The trace elements aluminium, cadmium, calcium, chromium, cobalt, copper, lead, magnesium, manganese, mercury, potassium, sodium, vanadium, and zinc are determined in the aqueous phase by atomic-absorption spectrophotometry

  8. Interaction of kaolin containing ores with natrium and calcium chlorides

    International Nuclear Information System (INIS)

    Sokhibov, I.Sh.; Dadabaeva, G.; Mirzoev, B.; Safiev, H.; Boboev, Kh.E.

    1997-01-01

    The impact of different factors on ore agglomeration at presence of carbon activators CaCl 2 and NaCl 2 was studied. The impact of different factors on water and hydrochloric acid processing of obtained cake was studied as well. The temperature influence was studied at temperature range 600-1000 deg C during 90 min sintering. The obtained cakes were leached by water in acid medium and were used as coagulants for water purification from suspended matters.

  9. Effectiveness acidic pre-cleaning for copper-gold ore

    Directory of Open Access Journals (Sweden)

    Antonio Clareti Pereira

    Full Text Available Abstract The presence of copper-bearing minerals is known to bring on many challenges during the cyanidation of gold ore, like high consumption of cyanide and low extraction of metal, which are undesirable impacts on the auriferous recovery in the subsequent process step. The high copper solubility in cyanide prevents the direct use of classical hydrometallurgical processes for the extraction of gold by cyanidation. Additionally, the application of a conventional flotation process to extract copper is further complicated when it is oxidized. As a result, an acid pre-leaching process was applied in order to clean the ore of these copper minerals that are cyanide consumers. The objective was to evaluate the amount of soluble copper in cyanide before and after acidic cleaning. From a gold ore containing copper, the study selected four samples containing 0.22%, 0.55%, 1.00% and 1.36% of copper. For direct cyanidation of the ore without pre-treatment, copper extraction by cyanide complexing ranged from 8 to 83%. In contrast, the pre-treatment carried out with sulfuric acid extracted 24% to 99% of initial copper and subsequent cyanidation extracted 0.13 to 1.54% of initial copper. The study also showed that the copper contained in the secondary minerals is more easily extracted by cyanide (83%, being followed by the copper oxy-hydroxide minerals (60%, while the copper contained in the manganese oxide is less complexed by cyanide (8% a 12%. It was possible to observe that minerals with low acid solubility also have low solubility in cyanide. Cyanide consumption decreased by about 2.5 times and gold recovery increased to above 94% after acidic pre-cleaning.

  10. Determination of tin in cassiterite ores by colorimetry of iodometry

    International Nuclear Information System (INIS)

    Rodriguez Hernandez, B.

    1972-01-01

    The analytical methods are described far the determination of tin in cassiterite ores. The gallein-colorimetric method is described for determining small amounts of tin, covering the 0,01-0,5 per cent range. The sample is decomposed by heating with ammonium iodide, and tin is analyzed colorimetrically by means of it s complex with gallein. The final measure may be brought about either visually or spectrophotometrically at 525 nm. (Author)

  11. Mineralogical study of uraniferous graphitic ore from Deogpyeong, Mogso and southern part of Daejeon area

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D J; Nam, S K [Korean Inst. of Energy and Resources, Seoul (Republic of Korea)

    1981-11-01

    Uranium minerals of torbernite, metatorbernite, metatyuyamunite and autunite have been identified from the uraniferous ores in graphitic beds of Ogcheon Group in Deogpyeong, Mogso and southern part of Daejeon area. Polarizing and ore microscopic studies, and chemical and X-ray powder diffraction analyses were carried out on the uraniferous graphite and associated materials. Main component minerals of uraniferous samples are graphite and quartz. Minor minerals are calcite, muscovite, sericite, andalusite, barite, kaolinite, hyaline opal, uranium minerals, sulfides such as pyrite, chalcopyrite, zincblende, and pyrrhotite, limonite, zeolite minerals such as laumontite and heulandite. Metatyuyamunite, torbernite, metatorbernite and autunite generally occur together with secondary minerals such as kaolinite, hyaline opal, calcite and limonite. They were found along the minor fissures or on the surface. Secondary uranium minerals described above were formed by supergenetic origin from primary uranium mineral. Uraniferous phosphatic nodule from Deogpyeong area are mainly composed of graphite and fluorapatite. And minor minerals are barite, quartz, muscovite and pyrite. Autoradiograph from uraniferous nodule shows that uranium enrichment in outer part of nodules is much higher than in inner part. This feature coincides with chemical analyses data of this uraniferous nodule.

  12. Quantitative analysis of phases by x-ray diffraction and thermogravimetry in Cuban phosphorite ores

    International Nuclear Information System (INIS)

    Casanova Gomez, Abdel; Martinez Montalvo, Asor; Cilano Campos, Guillermo; Arostegui Aguirre, Miladys; Ferreiro Fernandez, Adalyz; Alonso Perez, Jose A.

    2016-01-01

    Phases analysis is performed by instrumental techniques X - ray diffraction and Thermal Analysis in two groups of samples of Cuban minerals carriers'phosphorus, candidates to reference materials. To this end, the variant of structural refinement of the diffraction pattern in the form of adjustment profile is applied, using the Full prof program of Juan Rodriguez-Carvajal. This analysis is the first step to develop the standard specification of these resources and classify them as phosphate rock and / or phospharite from their mass content. The statistical evaluation of the uncertainty of the quantitative analysis (standard deviation) was carried out in ten replicate samples of phosphate rock and eight of phosphate from the field Trinidad de Guedes. The qualitative phase analysis reflected the following phase composition: carbonate fluoroapatite (CFA), Calcite, Quartz and Halloysite (present only in the clayey granular phosphorite ore; FGA). By the method of setting pattern powder diffraction profile, the quantitative phase composition is reported in the sample FGA: 87 (2) % of CFA, 4 (1) % of Calcite, 1% Quartz, and 8 (3) % Halloysite. For granular limestone ore (FGC), the following contents were obtained: 87 (3) % Calcite, 8 (3) % of CFA and 5 (1) % Quartz: The obtained values are corroborated by Thermogravimetric Analysis (TG) through the calculation of the mass content of the thermally active phases (Calcite and CFA) in the range (27-10000 0 C), confirming the validity of the results of XRD. (Author)

  13. User's guide for the Uranium Ore Reserve Calculation System (URAD)

    International Nuclear Information System (INIS)

    1988-12-01

    The URAD (Uranium Reserves and Data) system consists of four computer programs designed to facilitate the evaluation of uranium ore reserves analysis and the handling of basic uranium assay data. URAD is designed specifically as a training tool for anyone unfamiliar with the methodology, data requirements, and/or general computer applications in the field of uranium ore reserves analysis. However, it can effectively be used in a 'production' environment involving considerable amounts of data. The resulting programs are written in Microsoft FORTRAN (Version 3.1) and may be run on any IBM-compatible microcomputer under DOS 2.1 (or later). Only a basic working knowledge of DOS 2.1 is needed to maintain the system and run the programs. This guide includes the overview of the URAD system, the review of sample data and a complete description of the file structure and sample type formats of the basic sample data files. Program URDAT explains the initial processing of the primary UDAT files to obtain standard output listings and gamma-log interpretations of radiometric data, and to create intermediate UDAT files which are used by the ore reserves programs - RESUV, ORSAC, and SCOR. Figs and tabs

  14. Effect of moisture content on the flowability of crushed ores

    Science.gov (United States)

    Cabrejos, Francisco

    2017-06-01

    In many mining and industrial processes where large quantities of non-degrading bulk materials such as crushed ores are handled, silos, hoppers, stockpiles and chutes are widely used because they are economical and reliable (if properly designed and operated). However, they are not free of trouble and may experience flow problems such as arching, ratholing, erratic flow, limited storage capacity, limited discharge flow rate, caking, segregation and/or flooding. Moisture content and fine particles significantly affect the flowability of most ores, increasing their cohesive strength and turning them more prone to these problems. The purpose of this article is to highlight a proven, scientific method that can be utilized to ensure reliable storage, flow and discharge of bulk solids in these equipment based on Jenike's flow-of-solids theory and laboratory testing. Knowledge of the flow properties of the material handled provides a design basis to ensure mass flow, avoid arching and prevent the formation of "ratholes". The effect of an increase in water content of the ore is discussed with experimental results.

  15. Effect of moisture content on the flowability of crushed ores

    Directory of Open Access Journals (Sweden)

    Cabrejos Francisco

    2017-01-01

    Full Text Available In many mining and industrial processes where large quantities of non-degrading bulk materials such as crushed ores are handled, silos, hoppers, stockpiles and chutes are widely used because they are economical and reliable (if properly designed and operated. However, they are not free of trouble and may experience flow problems such as arching, ratholing, erratic flow, limited storage capacity, limited discharge flow rate, caking, segregation and/or flooding. Moisture content and fine particles significantly affect the flowability of most ores, increasing their cohesive strength and turning them more prone to these problems. The purpose of this article is to highlight a proven, scientific method that can be utilized to ensure reliable storage, flow and discharge of bulk solids in these equipment based on Jenike’s flow-of-solids theory and laboratory testing. Knowledge of the flow properties of the material handled provides a design basis to ensure mass flow, avoid arching and prevent the formation of “ratholes”. The effect of an increase in water content of the ore is discussed with experimental results.

  16. Uranium and Molybdenum extraction from a Cerro Solo deposit ore

    International Nuclear Information System (INIS)

    Becquart, Elena T.; Arias, Maria J.; Fuente, Juan C. de la; Misischia, Yamila A.; Santa Cruz, Daniel E.; Tomellini, Guido C.

    2009-01-01

    Cerro Solo, located in Chubut, Argentina, is a sandstone type uranium-molybdenum deposit. Good recovery of both elements can be achieved by acid leaching of the ore but the presence of molybdenum in pregnant liquors is an inconvenient to uranium separation and purification. A two steps process is developed. A selective alkaline leaching of the ore with sodium hydroxide allows separating and recovering of molybdenum and after solid-liquid separation, the ore is acid leached to recover uranium. Several samples averaging 0,2% uranium and 0,1% molybdenum with variable U/Mo ratio have been used and in both steps, leaching and oxidant reagents concentration, temperature and residence time in a stirred tank leaching have been studied. In alkaline leaching molybdenum recoveries greater than 96% are achieved, with 1% uranium extraction. In acid leaching up to 93% of the uranium is extracted and Mo/U ratio in solvent extraction feed is between 0,013 and 0,025. (author)

  17. Extracting phosphoric iron under laboratorial conditions smelting bog iron ores

    International Nuclear Information System (INIS)

    Török, B; Thiele, A

    2013-01-01

    In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well

  18. On the problems of the Litija ore field

    Directory of Open Access Journals (Sweden)

    Ivan Mlakar

    1994-12-01

    Full Text Available All available information on the now inaccessible Pb-Zb-Ba deposits Litija, Zavrstnik, Zagorica, Maljek, Hrastarija and Štriglovec was critically evaluated. Data were completed and numerous earlier unsolved questions were answered.In the studied area the existence of a Middle Triassic tectonic-erosional phase was proved, the Old Tertiary overthrust structure analyzed and the relative ages of various neotectonic fault systems established.Special attention was attributed to the Litija, or Sitarjevec, deposit. On the ground of data on position of thick shale intercalations within Carboniferous sandstone the geological structure of the deposit was reconstructed, proofs on the conforming or unconforming position of orebodies collected, and certain relati¬onships between the pre-ore and post-ore tectonics clarified. With geochemical investigations the presence of an extensive dispersion halo was proved, in which the anomalies produced by Pb, Hg and Ba are the best expressed.Also the position of other deposits in space and in stratigraphic column was defined. At the end also the author's views on genesis and age of mineralization are presented. Orebodies are hydrothermal. subvertical, epignetic and predominantly discordant, with poorly expressed vertical zoning.The work is a synthesis of understanding of geological structure and mineralization in the Litija ore field.

  19. Uranium ore mill at Dolni Rozinka: 40 years of operation

    International Nuclear Information System (INIS)

    Toman, F.; Jezova, V.

    2007-01-01

    Uranium ore mined in the Rozna deposit is treated at a chemical treatment plant (a mill) situated in the close vicinity of the Rozna mine. In the mill, uranium is extracted from the crushed and ground-up ore by alkaline leaching. Uranium is then recovered from the solution by sorption on ion exchange resin; the next steps are precipitation and drying. Alkaline leaching is applied at the atmospheric pressure and the temperature of 80 deg C; the recovery factor is moving around 93%. The final product of the milling is uranium concentrate, ammonium diuranate (NH 4 ) 2 U 2 O 7 ), a so-called 'yellow cake' which is treated into a fuel for nuclear power plants in conversion facilities abroad. The milling is carried on under the condition of the closed cycle of technology water. Due to the positive annual precipitation balance, the over balance of technology water in tailings pond has to be purified before discharging into a river. Evaporation and membrane processes (electrodialysis and reverse osmosis) are used to purify the water. The mill at Dolni Rozinka has been in operation since 1968. It has processed 13.2 million tons of uranium ore which is about 14000 tons of uranium and purified more than 6 million m 3 of the over balanced technology water during 40 years. From the organizational point of view, the mine and the chemical treatment plant form the branch plant GEAM, which is a part of the state enterprise DIAMO. (author)

  20. Contact mechanical analysis of O-ring stresses

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Kyu

    2007-02-15

    The purpose of this project is to develop the approximate solutions of contact traction and internal stress of an O-ring by using a two dimensional elasticity for enhancing the design and failure prediction technology. Investigated were the applicability of Lindley's formulae of contact force prediction and the Hertz theory. Three cases of O-ring installation were considered. The approximate solution of contact tractions and internal stresses of each case were derived. The key results are summarized as follows: 1. It is verified that Lindley's formulae predicts the relationship between the fractional compression and contact force. 2. In the case of Case I, II and III without internal pressure, it is found that a function form of the contact traction is the Hertzian. So it is possible to express the traction with a Hertzian form and correction factors. 3. The internal stresses are derived in the case of the Hertzian traction profile. The stresses at the center of O-ring show a satisfactory result when compared with the finite element result.

  1. Automation of the second iron ore slurry pipeline from Samarco

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, Juliana M.; Fonseca, Mario L.; Drumond, Pablo P.; Barbosa, Sylvio [IHM Engenharia, Belo Horizonte, MG (Brazil)

    2009-07-01

    The second iron ore slurry pipeline from Samarco was build to attend the Third Pellet Plant Project, which includes a new Concentration Plant at Germano-MG and a third Pellet Plant at Ubu-ES. It has 396km of extension and links the two plants by pulping the iron ore slurry prepared at Germano Unit. This works aims to present the iron ore slurry pipeline with emphasis on the automation architecture for the supervision and control system, interconnect throughout the pipe extension by fiber optics. The control system is composed of ControlLogix CLP's at the pulping and valve station and Micrologix CLP's at the pressure and cathodic protection monitoring points, totalizing 19 PLC's. The supervisory system was developed using the Wonderware IAS 3.0 suite, including the supervisory software InTouch 9.5 and the integrated ArchestrA IDE, and is composed of two data servers in redundancy and nine operation stations. The control and supervision system is interconnect through and Ethernet network using fiber optics and multiplexer modules (GE JungleMux) for voice, data and video. Among the expected results, it can be highlighted the sequence automation, greater process data availability (real and historical) and greater facility for the operation and detection of failures. (author)

  2. Problems in the separation of radium from uranium ore tailings

    Energy Technology Data Exchange (ETDEWEB)

    Seeley, F.G.

    1976-01-01

    The radium content of a representative sandstone type of uranium ore was found to be distributed uniformly according to particle size before leaching, but in sulfuric acid-leached tailings was found predominantly in the -325 mesh fraction. The radium leaching characteristics from both ore and sulfate-leached tailings were investigated. Several 1 M salt solutions showed poor to moderate RaSO/sub 4/ dissolution from ''slimes solids'' tailings, while 3 M HNO/sub 3/ or HCl solutions dissolved approximately 95% of the radium content of either ore or tailings. Tests are reported in which -325 mesh sand particles were coated with alkaline-earth sulfates by a special technique to simulate slime solids tailings. The dissolution of RaSO/sub 4/ from these coated sands was decreased by the presence of BaSO/sub 4/, but increased by the presence of CaSO/sub 4/. The interrelationships in the dissolution of mixtures of CaSO/sub 5/, SrSO/sub 4/, BaSO/sub 4/, and RaSO/sub 4/ are shown, and a generalized equation for the estimation of the dissolution of a minor component is presented.

  3. Ore lead isotope ratios in a continually changing Earth

    International Nuclear Information System (INIS)

    Cumming, G.L.; Richards, J.R.

    1975-01-01

    A critical reassessment of the construction of simple ore lead isotopic development curves is followed by three fresh approximations, all designed to involve the minimum possible number of assumptions. All are based on the Russell-Reynolds algorithm, when in its simplest form involves knowledge only of ratios, not of ages. The calculations are applied to a restricted class of ore leads, and the latest constant values for the U and Th isotopes are employed. Model I treats all data as being of equal weight, and shows that the deletion or inclusion of the Canyon Diablo meterorite data makes no difference to the derived parameters. Model II demonstrates that essentially the same parameters result if the simple curve is forced through the meteorite point; i.e. questions about homogeneity or otherwise of 'initial terrestrial'Pb are unimportant to the regression . Model III makes allowance for the known discrepancy in young 'model ages' by providing for a steady linear change in U/Pb and Th/Pb. The additional assumption of one fixed time point proves necessary. An age close to 430 m.y.for Captains Flat, N.S.W., yields acceptable age estimates for most other deposits investigated. No claim is made for the uniquences of this solution, but the derived evidence for steady growth in U/Ph accompanied by a slight decline in Th/U seems compatible with a crustal source for the lead ores concerned. (Auth.)

  4. Lead isotope ratios in Japanese galena ores and archaeological objects

    International Nuclear Information System (INIS)

    Yamasaki, Kazuo; Murozumi, Masayo; Nakamura, Seiji; Hinata, Makoto; Yuasa, Mitsuaki.

    1978-01-01

    Lead isotope ratios 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, 208 Pb/ 204 Pb, 207 Pb/ 206 Pb and 208 Pb/ 206 Pb in Japanese galena ores and archaeological bronze objects were determined by a Hitachi RMU-6 mass spectrometer using a rhenium single filament as a surface ionization device. Basic experimental conditions including detection limit, fractionation effect, memory effect, etc. were examined, and the accuracy of determination was checked using the CIT shelf standard No. 1. Archaeological bronze objects were dissolved in nitric acid and lead was extracted by the dithizone method using specially purified reagents in a so-called clean laboratory. When 0.5 μg lead was loaded on the rhenium filament with phosphoric acid and silica gel as stabilizers, an ion current of 10 -13 -- 10 -15 A due to Pb + was obtained and maintained stable for several hours. Coefficients of variation found for the isotope ratios 207 Pb/ 206 Pb and 208 Pb/ 206 Pb were 0.1 -- 0.5%. Lead isotope ratios are given for 17 Japanese galena ores and for archaeological bronze objects such as bronze bells, halberds (Yayoi period), Horyuji pagoda spire (7th century), and Northern Sung coins (11th century). A close resemblance of the isotope ratios was found between Japanese galena ores and some Japanese bronze objects of the 7th century, suggesting the use of the former as raw materials of the latter. (auth.)

  5. Uranium R and D directed to low-grade ores

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    The treatment of depleted uranium ores by in-situ leaching and by counterflow ion exchange in the USA is described. In-situ leaching is mainly suitable for sandstone deposits. The research was originally focused on leaching with an acid and with carbonates. Phosphoric acid appears to be a promising leaching agent. The equipment for continuous ion exchange may be used for sludge processing but the application depends on the type of equipment and mineralogy of processed ores. The method is advantageous for lower capital costs and for smooth operation. Ion exchange is also used for uranium extraction from mine waters in the USA as well as in Canada. For example, in Grants, New Mexico, a yield exceeding 90% was reached in mine waters only containing 5 to 7 ppm U 3 O 8 . In the future, the treatment of ores with a low uranium content will require more selective extraction methods in view of the more stringent technical conditions of uranium concentrate processing. (J.P.)

  6. Application of neutron activation analysis to control P2O5 content in ore and ore concentrates of ''Apatit'' works

    International Nuclear Information System (INIS)

    Belyakov, M.A.; Terent'eV, Eh.P.; Frolov, V.A.

    1982-01-01

    A technique for a neutron activation rapid analysis of fluorine is described. A mean-square error of the analysis makes up 0,g3 per cent F. The investigation has been carried out and a close correlation has been established for the Hibine massif exploited apatite deposits on the basis of the neutron activation analysis of fluorine and chemical analysis of P 2 O 5 . Possibilities are shown of using the neutron activation analysis of P 2 O 5 in ores and certain ore con-- centrates of ''Apatit'' works from the radioactivity induced in fluorine. A mean-square error of the analysis makes up 0,35 per cent P 2 O 5

  7. Gas migration characteristics of highly compacted bentonite ore

    International Nuclear Information System (INIS)

    Tanaka, Yukihisa; Hironaga, Michihiko

    2010-01-01

    In the current concept of repository for radioactive waste disposal, compacted bentonite will be used as an engineered barrier mainly for inhibiting migration of radioactive nuclides. Hydrogen gas can be generated inside the engineered barrier by anaerobic corrosion of metals used for containers, etc. If the gas generation rate exceeds the diffusion rate of dissolved gas inside of the engineered barrier, gas will accumulate in the void space inside of the engineered barrier until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. It is expected to be not easy for gas to entering into the bentonite as a discrete gaseous phase because the pore of compacted bentonite is so minute. Gas migration characteristics of highly compacted powdered bentonite are already reported by CRIEPI. In this report, gas migration characteristics of bentonite ore, which is a candidate for construction material of repository for radioactive waste, is investigated. The following conclusions are obtained through the results of the gas migration tests which are conducted in this study: 1) When the total gas pressure exceeds the initial total axial stress, the total axial stress is always equal to the total gas pressure because specimens shrink in the axial direction with causing the clearance between the end of the specimen and porous metal. By increasing the gas pressure more, gas breakthrough, which defined as a sudden and sharp increase in gas flow rate out of the specimen, occurs. Therefore gas migration mechanism of compacted bentonite ore is basically identical to that of compacted powdered bentonite. 2) Hydraulic conductivity measured after the gas breakthrough is somewhat smaller than that measured before the gas migration test. This fact means that it might be possible to neglect decline of the function of bentonite as engineered barrier caused by the gas breakthrough. These characteristics of compacted bentonite ore are identical to those of

  8. Direct Flotation of Niobium Oxide Minerals from Carbonatite Niobium Ores

    Science.gov (United States)

    Ni, Xiao

    Currently the recovery of niobium oxide minerals from carbonatite niobium ores relies on the use of non-selective cationic collectors. This leads to complicated process flowsheets involving multiple desliming and multiple reverse flotation stages, and low niobium recovery. In this research, anionic collectors that are capable of strong chemisorption on the niobium minerals were studied with the objective of directly floating the niobium oxide minerals from the carbonatite ores. In the flotation of both high purity minerals and Niobec ores, it was shown that the combination of hydroxamic acid and sodium metaphosphate was an effective reagent scheme for the direct flotation of niobium oxide from its ores. Batch flotation on the Niobec Mill Feed showed that over 95% of niobium oxide was recovered into a rougher concentrate that was less than 47% of the original feed mass. Preliminary cleaning tests showed that the reagent scheme could also be used to upgrade the rougher concentrate, although the depression of iron oxide minerals required further study. X-ray photoelectron spectroscopic (XPS) measurement results confirm that OHA (octyl hydroxamic acid) could chemisorb on pyrochlore surface while only physically adsorb on calcite, judging by the chemical shifts of electron binding energies in the elements in both OHA and the mineral surfaces. When hydroxamic acid was adsorbed on calcite surface, the binding energies of the N 1s electrons, at 400.3 eV, did not shift. However, after adsorption on pyrochlore, the N 1s binding energy peak split into two peaks, one at a binding energy of around 399 eV, representing chemically adsorbed OHA, the other at between 400 and 401 eV. The experimental data suggested a strong chemisorption of the OHA on pyrochlore surface in the form of a vertical head-on orientation of the OHA molecules so that the pyrochlore was strongly hydrophobized even at low OHA concentrations, followed by possibly randomly oriented physisorbed OHA molecules

  9. Bottle roll leach test for Temrezli uranium ore

    International Nuclear Information System (INIS)

    Çetin, K.; Bayrak, M.; Turan, A. İsbir; Üçgül, E.

    2014-01-01

    The bottle roll leach test is one of the dynamic leaching procedure which can meet in-situ mining needs for determining suitable working conditions and helps to simulate one of the important parameter; injection well design. In this test, the most important parameters are pulp density, acidic or basic concentration of leach solution, time and temperature. In recent years, bottle roll test is used not only for uranium but also gold, silver, copper and nickel metals where in situ leach (ISL) mining is going to be applied. For this purpose for gold and silver metal cyanide bottle roll tests and for uranium metal; acidic and basic bottle roll tests could be applied. The new leach test procedure which is held in General Directorate of Mineral Research and Exploration (MTA) of Turkey is mostly suitable for determining metal extraction conditions and recovery values in uranium containing ore bodies. The tests were conducted with samples taken from Temrezli Uranium Ore located in approximately 200 km east of Turkey’s capital, Ankara. Mining rights of Temrezli Ore is controlled 100% by Anatolia Energy Ltd. The resource estimate includes an indicated mineral resource of 10.827 Mlbs U_3O_8 [~4160 t U] at an average grade of 1426 ppm [~1210 ppm U] and an additional inferred resource of 6.587 Mlbs of U_3O_8 [~2530 t U] at an average grade of 904 ppm [~767 ppm U]. In accordance with the demand from Anatolia Energy bottle roll leach tests have been initiated in MTA laboratories to investigate the recovery values of low-grade uranium ore under in-situ leach conditions. Bottle roll leaching tests are performed on pulverized samples with representative lixiviant solution at ambient pressure and provide an initial evaluation of ore leachability with a rough estimate of recovery value. At the end of the tests by using 2 g/L NaHCO_3 and 0.2 g/L H_2O_2 more than 90% of uranium can pass into leach solution in 12 days. (author)

  10. A differently imagined margin: Initial Teacher Training and Black and Minority Ethnic groups in the Lifelong Learning Sector in the north of England

    Directory of Open Access Journals (Sweden)

    Rennie, Sandra

    2011-06-01

    Full Text Available We look at how marginal education spaces are differently imagined and (reproduced. We trace aspects of learners’ journeys and the different pathways into Initial Teacher Training (ITT made available through a university and an Adult Education-based networking organisation in the Lifelong Learning Sector (LLS in England. We focus on urban localities and the venues used to offer and run PTLLS courses aimed at attracting Black and Minority Ethnic (BME recruits to teaching careers. We compare the profiles of these trainee groups and the effect of the different approaches taken by these organisations. We look at organisational and spatial aspects of training ‘offers’ and provision, the impacts of this on the recruitment of learners and how teaching careers are differently imagined within this marginal space. We conclude with suggestions for altering the discourse used to review and plan the recruitment of BME teacher trainees.

  11. Identifying factors likely to influence compliance with diagnostic imaging guideline recommendations for spine disorders among chiropractors in North America: a focus group study using the Theoretical Domains Framework

    Directory of Open Access Journals (Sweden)

    Bussières André E

    2012-08-01

    Full Text Available Abstract Background The Theoretical Domains Framework (TDF was developed to investigate determinants of specific clinical behaviors and inform the design of interventions to change professional behavior. This framework was used to explore the beliefs of chiropractors in an American Provider Network and two Canadian provinces about their adherence to evidence-based recommendations for spine radiography for uncomplicated back pain. The primary objective of the study was to identify chiropractors’ beliefs about managing uncomplicated back pain without x-rays and to explore barriers and facilitators to implementing evidence-based recommendations on lumbar spine x-rays. A secondary objective was to compare chiropractors in the United States and Canada on their beliefs regarding the use of spine x-rays. Methods Six focus groups exploring beliefs about managing back pain without x-rays were conducted with a purposive sample. The interview guide was based upon the TDF. Focus groups were digitally recorded, transcribed verbatim, and analyzed by two independent assessors using thematic content analysis based on the TDF. Results Five domains were identified as likely relevant. Key beliefs within these domains included the following: conflicting comments about the potential consequences of not ordering x-rays (risk of missing a pathology, avoiding adverse treatment effects, risks of litigation, determining the treatment plan, and using x-ray-driven techniques contrasted with perceived benefits of minimizing patient radiation exposure and reducing costs; beliefs about consequences; beliefs regarding professional autonomy, professional credibility, lack of standardization, and agreement with guidelines widely varied ( social/professional role & identity; the influence of formal training, colleagues, and patients also appeared to be important factors ( social influences; conflicting comments regarding levels of confidence and comfort in managing patients

  12. Treatment of Colorectal Peritoneal Carcinomatosis With Systemic Chemotherapy: A Pooled Analysis of North Central Cancer Treatment Group Phase III Trials N9741 and N9841

    Science.gov (United States)

    Franko, Jan; Shi, Qian; Goldman, Charles D.; Pockaj, Barbara A.; Nelson, Garth D.; Goldberg, Richard M.; Pitot, Henry C.; Grothey, Axel; Alberts, Steven R.; Sargent, Daniel J.

    2012-01-01

    Purpose Symptoms and complications of metastatic colorectal cancer (mCRC) differ by metastatic sites. There is a paucity of prospective survival data for patients with peritoneal carcinomatosis colorectal cancer (pcCRC). We characterized outcomes of patients with pcCRC enrolled onto two prospective randomized trials of chemotherapy and contrasted that with other manifestations of mCRC (non-pcCRC). Methods A total of 2,095 patients enrolled onto two prospective randomized trials were evaluated for overall survival (OS) and progression-free survival (PFS). A Cox proportional hazard model was used to assess the adjusted associations. Results The characteristics of the pcCRC group (n = 364) were similar to those of the non-pcCRC patients in median age (63 v 61 years, P = .23), sex (57% males v 61%, P = .23), and performance status (Eastern Cooperative Oncology Group performance status 0 or 1 94% v 96%, P = .06), but differed in frequency of liver (63% v 82%, P < .001) and lung metastases (27% v 34%, P = .01). Median OS (12.7 v 17.6 months, hazard ratio [HR] = 1.3; 95% CI, 1.2 to 1.5; P < .001) and PFS (5.8 v 7.2 months, HR = 1.2; 95% CI, 1.1 to 1.3; P = .001) were shorter for pcCRC versus non-pcCRC. The unfavorable prognostic influence of pcCRC remained after adjusting for age, PS, liver metastases, and other factors (OS: HR = 1.3, P < .001; PFS: HR = 1.1, P = .02). Infusional fluorouracil, leucovorin, and oxaliplatin was superior to irinotecan, leucovorin, and fluorouracil as a first-line treatment among pcCRC (HR for OS = 0.62, P = .005) and non-pcCRC patients (HR = 0.66, P < .001). Conclusion pcCRC is associated with a significantly shorter OS and PFS as compared with other manifestations of mCRC. Future trials for mCRC should consider stratifying on the basis of pcCRC status. PMID:22162570

  13. [North] Korea.

    Science.gov (United States)

    1986-05-01

    In 1985, the population of the Democratic People's Republic of Korea (North Korea) stood at 20 million, with an annual growth rate of 2.3%. The infant mortality rate was 30/1000 live births and life expectancy was 66 years. The gross national product (GNP) was US$23 billion in 1984, with a per capita GNP of $1175. Both North Korea's labor force and natural resources have been concentrated in recent years on an effort to achieve rapid economic development. During the early 1970s, a large-scale modernization program involving the importation of Western technology, primarily in the heavy industiral sectors of the economy, was attempted and resulted in a massive foreign debt. North Korea has a strongly centralized government under the control of the communist Korean Workers' Party. Literacy in the country is at the 99% level. Medical treatment is free. There is 1 physician/600 population and 1 hospital bed/350 inhabitants.

  14. The recovery of gold from refractory ores by the use of carbon-in-chlorine leaching

    Science.gov (United States)

    Greaves, John N.; Palmer, Glenn R.; White, William W.

    1990-09-01

    Recently, the U.S. Bureau of Mines examined the recovery of gold by chlorination of refractory carbonaceous and sulfidic ores, comparing various treatment methods in which a ground ore pulp is contacted with chlorine gas and activated carbon is added to the pulp for a carbon-in-chlorine leach (CICL). The objective of this research was to demonstrate the basic feasibility of CICL technology. Results showed that the organic carbon deactivating environment of CICL lowers, but does not eliminate, the adsorption of gold on activated carbon. In this environment, the refractory ore is altered, and gold is extracted and then recovered on activated carbon. With highly carbonaceous ores, CICL achieved a higher recovery than with primarily sulfidic refractory ores. Basic cyanide amenability testing of two carbonaceous ores achieved recoveries of only 5.5% and 46%. With CICL treatment, recoveries on carbon were 90% and 92%.

  15. Metalogenic study of the uraniferous ore deposit at La Coma, Municipio of General Bravo, N.L. Mexico

    International Nuclear Information System (INIS)

    Ferriz D, H.

    1977-01-01

    The uraniferous ore deposit at la Coma is located in a sandy-clayish sequence of the cold formation (non marine member) of the middle oligocene under peneconcordant lenses within a sandy body, situated on the North flank of a microdelta formed by small streams which ran from West to East. The metalogenic study of this ore deposit, permits us to establish mineralization controls and guides for the optimization of the uranium prospecting in the miogeoclinical of the Gulf of Mexico setting. The study was carried out on the basis of sedimentalogic and metalogenic criteria, and it was found that the mineralization process seems to be related to the formation and filling of a paleochannel which cut the microdelta permeable beds. The uraniferous solutions migrated through the conglomeratic filling of the paleochannel and reached this way the permeable horizons of the microdelta, where they infiltrated adopting a pattern like an apron. In the sites where the solutions reached sandy lenses rich in organic matter, the soluble compounds containing the uranium suffered a decomposition with the consequent absorption of the uranium by the organic matter, due to the decrease of the pH value. In conclusion, the favorableness of the environment for mineralization is defined by the convergence of the described paleo-geomorphologic elements. (author)

  16. Practices of entomophagy and entomotherapy by members of the Nyishi and Galo tribes, two ethnic groups of the state of Arunachal Pradesh (North-East India).

    Science.gov (United States)

    Chakravorty, Jharna; Ghosh, Sampat; Meyer-Rochow, Victor Benno

    2011-01-14

    We prepared a consolidated list of edible and therapeutic insects used in Arunachal Pradesh (N.E. India) by two tribal societies (i.e., the Nyishi of East Kameng and the Galo of West Siang). The list is based on thorough, semi-structured field-interviews with 20 informants of each tribal group. At least 81 species of local insects, belonging to 26 families and five orders of insects, namely Coleoptera (24 species), Orthoptera (17 species), Hemiptera (16 species), Hymenoptera (15 species) and Odonata (9 species), are being used as food among members of these two indigenous societies. However, Nyishi use overall more species of insects as food than Galo people do and consume mostly Coleoptera and Hemiptera; amongst the Galo, on the other hand, Odonata and Orthoptera dominate. The selection of the food insects amongst the Nyishi and Galo is dictated by traditional tribal beliefs as well as the taste and availability of the insects. Depending on the species, only particular or all developmental stages are consumed. Some food insects may be included in the local diet throughout the year, others only when seasonally available. Commonly specimens are being prepared for consumption by roasting, frying or boiling. Twelve species of insects are deemed therapeutically valuable by the locals and are being used by the tribes investigated to treat a variety of disorders in humans and domestic animals. Members of the Galo use a greater number of insect species for remedial purposes than the Nyishi. With the degradation of natural resources, rapid population growth, and increasing influence of 'westernization', the traditional wisdom of entomophagy and entomotherapy is at risk of being lost. There is thus an urgent need to record the role insects play as components of local diets and folk remedies and to assess insect biodiversity in the light of these uses.

  17. Practices of entomophagy and entomotherapy by members of the Nyishi and Galo tribes, two ethnic groups of the state of Arunachal Pradesh (North-East India

    Directory of Open Access Journals (Sweden)

    Ghosh Sampat

    2011-01-01

    Full Text Available Abstract We prepared a consolidated list of edible and therapeutic insects used in Arunachal Pradesh (N.E. India by two tribal societies (i.e., the Nyishi of East Kameng and the Galo of West Siang. The list is based on thorough, semi-structured field-interviews with 20 informants of each tribal group. At least 81 species of local insects, belonging to 26 families and five orders of insects, namely Coleoptera (24 species, Orthoptera (17 species, Hemiptera (16 species, Hymenoptera (15 species and Odonata (9 species, are being used as food among members of these two indigenous societies. However, Nyishi use overall more species of insects as food than Galo people do and consume mostly Coleoptera and Hemiptera; amongst the Galo, on the other hand, Odonata and Orthoptera dominate. The selection of the food insects amongst the Nyishi and Galo is dictated by traditional tribal beliefs as well as the taste and availability of the insects. Depending on the species, only particular or all developmental stages are consumed. Some food insects may be included in the local diet throughout the year, others only when seasonally available. Commonly specimens are being prepared for consumption by roasting, frying or boiling. Twelve species of insects are deemed therapeutically valuable by the locals and are being used by the tribes investigated to treat a variety of disorders in humans and domestic animals. Members of the Galo use a greater number of insect species for remedial purposes than the Nyishi. With the degradation of natural resources, rapid population growth, and increasing influence of 'westernization', the traditional wisdom of entomophagy and entomotherapy is at risk of being lost. There is thus an urgent need to record the role insects play as components of local diets and folk remedies and to assess insect biodiversity in the light of these uses.

  18. Practices of entomophagy and entomotherapy by members of the Nyishi and Galo tribes, two ethnic groups of the state of Arunachal Pradesh (North-East India)

    Science.gov (United States)

    2011-01-01

    We prepared a consolidated list of edible and therapeutic insects used in Arunachal Pradesh (N.E. India) by two tribal societies (i.e., the Nyishi of East Kameng and the Galo of West Siang). The list is based on thorough, semi-structured field-interviews with 20 informants of each tribal group. At least 81 species of local insects, belonging to 26 families and five orders of insects, namely Coleoptera (24 species), Orthoptera (17 species), Hemiptera (16 species), Hymenoptera (15 species) and Odonata (9 species), are being used as food among members of these two indigenous societies. However, Nyishi use overall more species of insects as food than Galo people do and consume mostly Coleoptera and Hemiptera; amongst the Galo, on the other hand, Odonata and Orthoptera dominate. The selection of the food insects amongst the Nyishi and Galo is dictated by traditional tribal beliefs as well as the taste and availability of the insects. Depending on the species, only particular or all developmental stages are consumed. Some food insects may be included in the local diet throughout the year, others only when seasonally available. Commonly specimens are being prepared for consumption by roasting, frying or boiling. Twelve species of insects are deemed therapeutically valuable by the locals and are being used by the tribes investigated to treat a variety of disorders in humans and domestic animals. Members of the Galo use a greater number of insect species for remedial purposes than the Nyishi. With the degradation of natural resources, rapid population growth, and increasing influence of 'westernization', the traditional wisdom of entomophagy and entomotherapy is at risk of being lost. There is thus an urgent need to record the role insects play as components of local diets and folk remedies and to assess insect biodiversity in the light of these uses. PMID:21235790

  19. The performance of leaching and bio-leaching from sulphide ores usiing SEVOP

    OpenAIRE

    Krstev, Boris; Krstev, Aleksandar; Golomeov, Blagoj; Golomeova, Mirjana; Sala, Ferat; Gocev, Zivko; Zivanovic, Jordan; Krstev, Dejan

    2013-01-01

    The refractory or low grade copper chalcopyrite ores or galena/sphalerite domestic ores in Republic of Macedonia are investigated by conventional copper flotation and selective flotation for galena/sphalerite. In the meantime, investigations are directed to the new possibilities of leaching by microorganisms – bioleaching. The paper is result of these technologies and investigations carried out for recovery of in the mentioned ores. Using Simplex EVOP and computer programme. Multisimple...

  20. INAA of Zn and impurity elements in Zn ores and concentrates

    International Nuclear Information System (INIS)

    Op de Beeck, J.; De Norre, L.; Hoste, J.

    1985-01-01

    The present work concerns the analysis of zinc ores and concentrates. In the first place a procedure for the routine determination of fluorine in Zinc sulfide ores has been developed, based on activation with the fast neutrons of the isotope source. In the second place a procedure for the routine determination of Cadmium in Zinc ores has been developed and finally the routine determination of Zinc itself is at present being completed

  1. Extraction of metals from ores by bacterial leaching: present status and future prospects

    International Nuclear Information System (INIS)

    Kelly, D.P.

    1977-01-01

    The principal organism effecting bacterial leaching of ferrous and sulfide ores is Thiobacillus ferrooxidans, though other thiobacilli and other bacteria may be involved. The process depends on (a) direct solubilization of metal sulfides by bacterial oxidation; (b) dissolution of metal sulfides or oxides by ferric iron produced by bacterial pyrite oxidation. Mining spoil dumps and low grade ores can be leached for copper or uranium by cheap low-level technology. Dump leaching enables maximum recovery of valuable metal from any ore, but makes possible exploitation of very low grade Cu and U ores. Continuous extraction processes are possible where a continuously growing bacterial culture is fed with pyritic ores (or FeSO 4 or other sulfide) and continuous metal solubilization proceeds. Intimate contact between the bacteria and the ore to be leached (especially with uranium oxide ores) is not always necessary: leaching of UO 2 ores probably depends only on ferric iron reaction with the ore. Degradation of pyrite-containing rocks may also be developed as part of future recovery processes for petroleum from oil shales. Two-stage leaching systems present the best prospect for developing a higher-level technology for metal extraction. State 1: bacterial generation of Fe 3+ from pyrite or a Fe 2+ source; Stage 2: chemical leaching of ore by Fe 3+ in acid solution. Two-stage processes can be surface processes using crushed or milled ores or can be applied to underground solution mining, when an ore (e.g. uranium) can be leached by pumping Fe 3+ solutions through shattered underground deposits, metal recovered (e.g. solvent extraction) and Fe 3+ regenerated by bacterial oxidation at the surface. The use of controlled continuous microbial cultures to generate either bacteria or ferric iron is outlined

  2. Chapter 1. General information about uranium. 1.3. Uranium ores

    International Nuclear Information System (INIS)

    Khakimov, N.; Nazarov, Kh.M.; Mirsaidov, I.U.

    2012-01-01

    The uranium ores were described. It was found that uranium ores and natural mineral formations containing uranium and its compounds, can be found in concentrations that are technically possible for industrial utilization and which are economically profitable. It was defined that oxidation levels of uranium minerals have an impact on their reprocessing technology and behavior in hydrometallurgical re partition. It was found that the chemical composition of ores has a decisive importance during selection of their reprocessing method.

  3. Evaluation of serpentine ore as a nuclear shielding material using gas chromatographic techniques

    International Nuclear Information System (INIS)

    Singh, B.N.; Unnikrishnan, E.K.; Kumar, Sangita D.

    2007-01-01

    Serpentine ore mixed with cement has been recognized as a candidate shielding material for use in nuclear reactors because of its many desirable properties. Therefore the assessment of serpentine ore for release of volatile gases during exposure to elevated temperatures, irradiation and changes in chemical composition, is essential. The present paper deals with the studies on the serpentine ores using gas chromatography and combustion gas chromatographic techniques. (author)

  4. Decomposition of silica-alumina ores of Afghanistan by sulfuric acid

    International Nuclear Information System (INIS)

    Khomidi, A.K.; Mamatov, E.D.

    2016-01-01

    Present article is devoted to decomposition of silica-alumina ores of Afghanistan by sulfuric acid. Physicochemical properties of initial silica-alumina ores were studied by means of X-ray phase, differential thermal and silicate analysis. The influence of temperature, process duration and acid concentration on extraction rate of valuable components was considered. The optimal conditions of decomposition of silica-alumina ores of Afghanistan by sulfuric acid were proposed.

  5. Analysis of Characteristics of Ore about Iron Deposit of Da Hong Mountain in Yun Nan Province

    Directory of Open Access Journals (Sweden)

    Zhang Yuefeng

    2016-01-01

    Full Text Available This thesis aims to analyse the deposit characteristics about Da Hong Mountains Iron ore in Yunnan province. The texture and structure, especially the chemical composition, is different in every section of deposit after comparing. Moreover, the content of SiO2 is much higher than general iron ore. However, the content of other noble metals cannot reach the lowest industrial grade. Da Hong Mountains Iron ore has unique features because of metallogenic periods.

  6. Status Report from Yugoslavia [Processing of Low-Grade Uranium Ores

    Energy Technology Data Exchange (ETDEWEB)

    Bunji, B [Institute for Technology of Nuclear and Other Raw Materials, Belgrade, Yugoslavia (Serbia)

    1967-06-15

    barren solution has resulted in important savings on reagent. The overall economy compared under local conditions with ion-exchange or solvent extraction is in favour of the reduction process. Some research work on heap leaching and leaching in situ is included in our activities. In connection with the conditions at Kalna it was possible to carry out large-scale heap leaching and leaching in situ. The former was carried out on waste rocks with a uranium content below the cut-off grade. To avoid solution losses, the surface area from the heap pile is covered with thin plastic sheets. Good drainage from the bottom is obtained by using perforated 10-in. asbestos-concrete pipes. The technique of construction of the heap pile is as usual, and mostly depends on local conditions. The heap leach pile is about 12 m high. The solution retention time is about 8 days. The barren solution from the reduction plant or mine water with a uranium content in the range of 2 to 6 g/m{sup 3} is used for the heap leaching. The pregnant solution is returned into the processing plant. Because the heap leach pile obtained is practically without any charge, the operating and the construction costs of the heap pile need only be in balance with the value of the recovered uranium. Investigation of bacterial leaching has shown some influence on the leaching rate. The bacteria belonging to the Thiobacillus-Ferrobacillus group were obtained from mine water, selected and cultivated. It seems that the concentration of bacteria has some influence on the extraction time and percentage of extracted uranium, and it can be said that the application of bacteria in heap leaching and leaching in situ will in the future be one of the most effective methods of uranium extraction from ore that is below cut-off grade. (author)

  7. Assessing the impact of iron ore mining to the groundwater in Goa, using stable isotopes

    International Nuclear Information System (INIS)

    Arzoo Ansari, Md.; Sinha, U.K.; Mohokar, H.V.; Deodhar, Archana; Mendhekar, G.N.; Jaryal, Ajay

    2017-01-01

    Goa contributes about 50% of the total iron ore exported from the country. Iron ore share is 95% of total mining and quarrying sector in Goa. It represents the second most important industry next to tourism. The iron ore is predominantly mined by opencast mining throughout Goa. The reduction of the forest cover, huge dumps, dust mineral particles, water contamination and health problems are some of the principal harmful effects of extensive mining which is of great concern to the environment. The objective of this study is to assess the impact of iron ore mining to groundwater in downstream side of the mine pits using isotope hydrological techniques

  8. Taoshan uranium ore fields in situ blasting heap leaching rate influence factors to investigate

    International Nuclear Information System (INIS)

    Xie Wangnan; Dong Chunming

    2014-01-01

    Taoshan ore field ore in situ blasting heap leaching out build industrial test and production process, stope leaching rate and leaching cycle is large than that, after analysis, blasting method and cloth liquid way is to affect leaching rate and leaching cycle of the main factors. This paper holds that as far as possible using stratified deep hole blasting of squeezing up ways to reduce the building pile of in-situ leaching ore block rate; Adopting effective cloth tube way, increase the leaching agent and ore contact comprehensive; Introduction of bacterial leaching, and other means to improve leaching rate, shorten production cycle, etc to solve it. (authors)

  9. Hydrogeochemical radioactive features and prospecting in granopegmatite type uranium ore district in Danfeng area

    International Nuclear Information System (INIS)

    Feng Zhangsheng

    2011-01-01

    Hydrochemical radioactive prospecting plays an important role in the all stages of grano-pegmatite type uranium deposit exploration in Danfeng area dut to its fast, simple, economic and high effective advantage. Radioactive anomalous halo in the shallow underground water has identical distribution scopes with the ore-bearing biotite granite-pegmatite, which can be used to delineate uranium ore-forming prospective area, reconnaissance area and detailed prospecting area. Deep underground water close to the ore is characterized by hydrogeochemical radioactive features with high uranium and radon content. Through prospecting engineering of radioactive hydrogeochemical, the situation of blind ore bodies can be used to guide the layout. (authors)

  10. A Review on New Technological Progress for Beneficiation of Refractory Phosphate Ore in China

    Science.gov (United States)

    Dong, Xu; Siqing, Liu; Yanqing, Yao; Hailin, Liu; Yi, Pei

    2017-05-01

    The world is rich in phosphate resources, but the vast majority of the resources are of middle and low grade ores, and it is difficult to obtain high grade concentrate at a high recovery by using traditional separation methods. In this paper, the distribution and flotation processes of typical phosphate ores in China are introduced. Considering the current situation in phosphate ore beneficiation both home and abroad, the new trend of processing technology and reagents in China are summarized. Flotation is still regarded as the main processing method in phosphate ore beneficiation for a certain time in near future.

  11. X-ray fluorescence separation of pure lead-zinc ores

    International Nuclear Information System (INIS)

    Lapshin, S.A.; Filippov, O.K.; Khachatryan, L.S.; Rudnev, B.P.

    1987-01-01

    To evaluate the influence of the previous concentration of polymetallic ores by the radiometric separation method on indices of flotation and gravitation enrichments, investigations were carried out using ore sample (1.94%Pb, 1.13% Zn) from a lead-zink ore deposit. It is shown that the results obtained on the enrichment of the ore and products of X-ray radiometric separation are similar. However previous removal (up to 40%) of dead rock permits to reduce sharply grinding and transpot costs

  12. Converting the Key Lake mill process for McArthur River ore

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, C. [McArthur River Operation, Cameco Corporation, Saskatoon, Saskatchewan (Canada)

    2000-07-01

    The Key Lake mill was commissioned in 1983 to process the two Key Lake ore deposits. With the depletion of these ore bodies in 1999, the plant was converted to mill the exceptionally rich McArthur River deposit located seventy eight kilometers northeast of the Key Lake mine site. This paper describes in detail the Key Lake milling process. The mill consists of a grinding circuit, a leach/counter current decantation circuit, a solvent extraction circuit, a yellowcake precipitation/calciner circuit, an ammonium sulphate crystallization circuit, and a waste treatment circuit. The paper also describes process changes to handle McArthur River ore, including the ore receiving station. (author)

  13. O-Ring sealing arrangements for ultra-high vacuum systems

    Science.gov (United States)

    Kim, Chang-Kyo; Flaherty, Robert

    1981-01-01

    An all metal reusable O-ring sealing arrangement for sealing two concentric tubes in an ultra-high vacuum system. An O-ring of a heat recoverable alloy such as Nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The O-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the O-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

  14. Electronic sorting of radioactive ores; Triage electronique des minerais radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Sandier, J.

    1958-01-15

    Electronic sorting of radioactive ores consists in passing the rock lumps, after sieving, one by one in front of radioactivity detectors; these detectors command electromechanical systems which class the ores according to their radioactivity level. This note sets on the state of progress of the work going on at the D.R.E.M.: use of scintillometers for γ-ray detection, with circuits carrying magnetic memories to improve their operation; results of laboratory and semi-industrial tests on several deposits; description of the material, data on the first factory project; notes on the financial returns of the process. A description is also given of the electronic sorting material used skip by skip for a first rough classification of the ores according to their content, as they leave the shaft. (author) [French] Le triage electronique des minerais radioactifs consiste a faire passer, apres criblage, les cailloux un par un devant des detecteurs de radioactivite; ces detecteurs commandent des systemes electromecaniques qui classent les minerais selon leur niveau de radioactivite. La note expose l'etat d'avancement des travaux en cours a la D.R.E.M: utilisation des scintillometres pour la detection des rayonnements γ, de circuits comportant des memoires magnetiques pour ameliorer le fonctionnement; resultats d'essais de laboratoire et semi-industriels sur plusieurs gisements; description du materiel, donnees sur le premier projet d'usine; notes sur la rentabilite du procede. Est egalement decrit le materiel de triage electronique skip par skip utilise pour une premiere classification grossiere des minerais selon leurs teneurs, des la sortie des puits. (auteur)

  15. [Bronchopulmonary diseases in workers engaged in deep-mined extraction of copper-nickel ore].

    Science.gov (United States)

    Siurin, S A; Derevoedov, A A; Nikanov, A N

    2008-01-01

    Examinations were made in 220 male workers exposed to dust-gas (low-silicon dioxide, nitric oxides, and carbon oxide) mixture, physical exercises, and cooling microclimate on deep-mined output of copper-nickel ore. Twenty-eight per cent of the workers were found to have evolving chronic bronchitis that did not substantially affect the patients' working capacity; 3.2% had chronic obstructive pulmonary disease and 1.4% had asthma that had developed before the onset of professional activity. 32.3% of the examinees were ascertained to have individual clinicofunctional disorders that permit their identification as a bronchopulmonary disease risk group to carry out early preventive and rehabilitative measures.

  16. Investigation on thermal oxidative aging of nitrile rubber (NBR) O-rings under compression stress

    Science.gov (United States)

    Liu, X. R.; Zhang, W. F.; Lou, W. T.; Huang, Y. X.; Dai, W.

    2017-11-01

    The degradation behaviors of nitrile rubber O-rings exposure to air under compression were investigated at three elevated temperatures. The physical and mechanical properties of the aging samples before and after exposure at selected time were studied by measuring weight loss, tensile strength and elongation at break. The Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and fracture morphology were used to reveal the microstructural changes of the aging samples. The results indicate that the weight decreased with exposure time and temperature. Based on the results of the crosslinking density, the crosslinking predominates during the most of aging process. The significant changes in tensile strength and elongation at break also indicate the severe degradation in air. The fracture morphology results show that the fracture surface after 64 days of exposure to air turns rough and present defects. The ATR-FTIR results demonstrate that the hydroxyl groups were formed for the samples aged in air.

  17. Use of the high-resolution satellite images for detection of fractures related to the ore deposits

    Science.gov (United States)

    Cruz-Mondaca, M.; Soto-Pinto, C. A.; Arellano-Baeza, A. A.

    2012-12-01

    The Aster and GeoEye satellite high-resolution images were used to detect the structures related to the fracturing of the upper crust in the North of Chile. In particular, lineament analysis has been applied to detect the presence of epithermal fluids of low sulfurization associated with the Paleozoic ore deposits. These results have been compared with the location of the minerals altered by the presence of geothermal fluids detected using the spectral libraries. Later, the presence of fractures has been corroborated during recognition of fractures in situ and the geochemical analysis of samples of minerals altered by the presence of fluids. It was shown that the results obtained are relevant for the gold vein detection.

  18. Surface modification and column flotation of a massive ilmenite ore

    International Nuclear Information System (INIS)

    Fan, X.; Rowson, N.A.

    2002-01-01

    The main problems with ilmenite flotation in impeller-type flotation machines are the poor flotation behaviour of ilmenite and the negative effect of slimes. These cause high ilmenite losses in tailings even when a large dosage of fatty acid and fuel oil is consumed. In this study, microwave radiation pre-treatment and ilmenite surface activation were used to modify the surface properties of a massive ilmenite ore sample from Norway to improve ilmenite flotability. A column cell was used to minimize the negative effect of slimes on ilmenite separation efficiency. When ilmenite flotation was performed in a 1 litre Denver cell, the flotation recovery of titanium dioxide from the ilmenite ore sample was only 68.5% (31.1% TiO 2 ) under conventional flotation conditions. After microwave radiation pre-treatment for three minutes at 2600 W and 2.45 GHz, the ferrous ions on ilmenite particle surfaces were converted into ferric ions; hence, the recovery increased from 68.5% to 86.8%. The concentrate grade increased from 31.1% TiO 2 to 32.1% TiO 2 . In ilmenite activation flotation, Pb 2+ ions can be selectively adsorbed on to ilmenite particle surfaces as active sites and therefore enhance the adsorption of oleate ions on ilmenite surfaces. With the addition of 60 g/ton Pb(NO 3 ) 2 , ilmenite flotation recovery increased from 68.5% to 85.1%. However, the quality of ilmenite concentrates was not improved due to the negative effect of slimes. After a two stage cleaning, the grade of ilmenite concentrates was only about 31% TiO 2 . The combination of microwave radiation pre-treatment and the application of a column cell overcame both problems of poor flotability and the negative effect of slimes. When the Denver cell was replaced by a column cell and the massive ilmenite ore sample was pre-treated using microwave radiation for three minutes, the ilmenite concentrate grade increased from 31.1% TiO 2 to 42.9% TiO 2 and the titanium dioxide recovery increased from 68.5% to 90

  19. Bioleaching of low-grade uranium ore using Acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Pal, S.; Das, T.; Sukla, L.B.; Roy Chaudhury, G.; Pradhan, D.

    2010-01-01

    Bioleaching of uranium was carried out with Turamdih ore sample procured from Uranium Corporation of India Limited, Jaduguda. The bacterial strain that was used in the leaching experiments was isolated from the Jaduguda mine water sample. Efficiency of bioleaching was studied by varying parameters like pulp density and initial ferrous concentration as source of energy. It is observed that the efficiency of bioleaching was 49% at 10% pulp density (w/v) and initial pH 2.0. Addition of external has no effect on efficiency of bioleaching showing domination of direct leaching mechanism over indirect. (author)

  20. Organic geochemistry of the Dongsheng sedimentary uranium ore deposits, China

    International Nuclear Information System (INIS)

    Tuo Jincai; Ma Wanyun; Zhang Mingfeng; Wang Xianbin

    2007-01-01

    Organic matter (OM) associated with the Dongsheng sedimentary U ore hosting sandstone/siltstone was characterized by Rock-Eval, gas chromatography-mass spectrometry and stable C isotope analysis and compared to other OM in the sandstone/siltstone interbedded organic matter-rich strata. The OM in all of the analyzed samples is Type III with Ro less than 0.6%, indicating that the OM associated with these U ore deposits can be classified as a poor hydrocarbon source potential for oil and gas. n-Alkanes in the organic-rich strata are characterized by a higher relative abundance of high-molecular-weight (HMW) homologues and are dominated by C 25 , C 27 or C 29 with distinct odd-to-even C number predominances from C 23 to C 29 . In contrast, in the sandstone/siltstone samples, the n-alkanes have a higher relative abundance of medium-molecular-weight homologues and are dominated by C 22 with no or only slight odd-to-even C number predominances from C 23 to C 29 . Methyl alkanoates in the sandstone/siltstone extracts range from C 14 to C 30 , maximizing at C 16 , with a strong even C number predominance, but in the organic-rich layers the HMW homologues are higher, maximizing at C 24 , C 26 or C 28 , also with an even predominance above C 22 . n-Alkanes in the sandstone/siltstone sequence are significantly depleted in 13 C relative to n-alkanes in most of the organic-rich strata. Diasterenes, ββ-hopanes and hopenes are present in nearly all the organic-rich sediments but in the sandstone/siltstone samples they occur as the geologically mature isomers. All the results indicate that the OM in the Dongsheng U ore body is derived from different kinds of source materials. The organic compounds in the organic-rich strata are mainly terrestrial, whereas, in the sand/siltstones, they are derived mainly from aquatic biota. Similar distribution patterns and consistent δ 13 C variations between n-alkanes and methyl alkanoates in corresponding samples suggest they are derived from