WorldWideScience

Sample records for twenty mineral processing

  1. A Mineral Processing Field Course

    Science.gov (United States)

    Carmody, Maurice

    2014-01-01

    This article describes a field course in Cornwall looking at mineral processing with the focus on the chemistry involved. The course was split into two parts. The first looked at tin mining based around Penzance. This involved visiting mines, hunting for mineral samples, carrying out a stream survey and visiting the Camborne School of Mines…

  2. Mineral Processing Technology Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2000-09-01

    This document represents the roadmap for Processing Technology Research in the US Mining Industry. It was developed based on the results of a Processing Technology Roadmap Workshop sponsored by the National Mining Association in conjunction with the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Office of Industrial Technologies. The Workshop was held January 24 - 25, 2000.

  3. Mineral processing of heavy mineral sands from Malawi and Malaysia

    OpenAIRE

    Mitchell, C J

    1992-01-01

    Processing of heavy mineral sands involves many techniques including gravity, magnetic and electrostatic separation. As part of a laboratory programme to develop effective mineral processing techniques, two mineral sands from Malawi and Malaysia were processed using the standard techniques, with emphasis placed on the Carpco electrostatic separator. These sands were initially characterised mineralogically by scanning electron microscopy (SEM), electron microprobe analysis (EPMA...

  4. Proceedings of XXIV international mineral processing congress

    Energy Technology Data Exchange (ETDEWEB)

    Wang Dianzuo; Sun Chuan Yao; Wang Fu Liang; Zhang Li Cheng; Han Long (eds.)

    2008-07-01

    Topics covered in volume 1 include applied mineralogy, comminution, classification, physical separation, flotation chemistry, sulphide flotation, non-sulphide flotation and reagent in mineral industry. Volume 2 covers processing of complex ores, processing of industrial minerals and coal, solid liquid separation, dispersion and aggregation, process simulation, expert systems and control of mineral processing, biohydrometallurgy, and mineral chemical processing. Volume 3 contains powder technology, mineral materials, treatment and recycling for solid wastes, waste water treatment, secondary resource recovery, soil remediation, concentrator engineering and process design, and application of mineral processing in related industry. It includes a CD-ROM of the proceedings.

  5. APPLICATION OF MICROBIAL TECHNOLOGY TO MINERAL PROCESSING

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The application of microbial technology to mineral processing has been reviewed with respect to the bioleaching of metals from minerals, the influence of biotreatment on flotation, the biobene ficiation of nonmetallic minerals, and the biotreatment for mine waste reclamation.The application of microbial technology to mineral processing has shown the advantages of high efficiency, low energy and reagent consumption, low capital and operating costs, and low pollution of the environment.

  6. Study on mineral processing technology for abrasive minerals

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seong Woong; Yang, Jung Il; Hwang, Seon Kook; Choi, Yeon Ho; Cho, Ken Joon; Shin, Hee Young [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-01

    Buyeo Materials in Buyeogun, Choongnam province is a company producing feldspar concentrate, but does not yet utilize the garnet as abrasive material and other useful heavy minerals wasted out from the process of feldspar ore. The purpose of this study is to develop technology and process for the recovery of garnet concentrate. As results, the garnet is defined as ferro manganese garnet. The optimum process for recovery of garnet concentrate is to primarily concentrate heavy minerals from tailings of feldspar processing. And secondly the heavy minerals concentrated is dried and separated garnet concentrate from other heavy minerals. At this time, the garnet concentrate is yield by 0.176%wt from 0.31%wt of heavy minerals in head ore. The garnet concentrate contains 33.35% SiO{sub 2}, 12.20% Al{sub 2}O{sub 3}, 28.47% Fe{sub 2}O{sub 3}, 11.96% MnO. As for utilization of abrasive materials, a fundamental data was established on technology of grinding and classification. (author). 13 refs., 47 figs., 24 tabs.

  7. Effect of mineral processing wastewater on flotation of sulfide minerals

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-ming; LIU Run-qing; SUN Wei; QIU Guan-zhou

    2009-01-01

    The effects of mineral processing wastewater on sulfide minerals were investigated by flotation, infrared spectrometry and electrochemistry test. The results show that lead-concentrate water can improve the flotation of galena, while the sulfur-concentrate water has negative effect on flotation of galena compared with distilled water. The flotation behavior of pyrite is contrary to that of galena in three kinds of water. Infrared spectra indicate that the residual collector in the lead-concentrate water is beneficial to the formation of lead xanthate on the surface of galena. Electrochemistry results indicate that electrochemistry reaction on galena surface has apparent change. The anode polarization is improved and cathode polarization is depressed.

  8. An Overview of Mineral Processing in China

    Institute of Scientific and Technical Information of China (English)

    曲恒磊; 周廉; 魏海荣; 赵永庆

    2001-01-01

    The latest progress in mineral processing in China is described. It is also pointed out that the existing techno logy can not meet the needs of economic development. The combined challenges of poor resources, economical benefits and environmental pollution issues require further research to upgrade the separation efficiency economically. The me thods of mineral processing should play a more important part in waste treatment such as wastewater treatment, the re mediation of contaminated soil and the recycling of wastes. Biomineral technology will be utilised in the near future.

  9. LEACHING OF METALS FROM MINERAL PROCESSING WASTE

    Science.gov (United States)

    The purpose of this project is to test the leaching of Mineral Processing Waste (MPW) contaminated with heavy metals using scientifically defendable leaching tests other than TCLP. Past experience and literature have shown that TCLP underestimates the levels of metals such as oxo...

  10. Tannins in Mineral Processing and Extractive Metallurgy

    Directory of Open Access Journals (Sweden)

    Jordan Rutledge

    2015-08-01

    Full Text Available This study provides an up to date review of tannins, specifically quebracho, in mineral processing and metallurgical processes. Quebracho is a highly useful reagent in many flotation applications, acting as both a depressant and a dispersant. Three different types of quebracho are mentioned in this study; quebracho “S” or Tupasol ATO, quebracho “O” or Tupafin ATO, and quebracho “A” or Silvafloc. It should be noted that literature often refers simply to “quebracho” without distinguishing a specific type. Quebracho is most commonly used in industry as a method to separate fluorite from calcite, which is traditionally quite challenging as both minerals share a common ion—calcium. Other applications for quebracho in flotation with calcite minerals as the main gangue source include barite and scheelite. In sulfide systems, quebracho is a key reagent in differential flotation of copper, lead, zinc circuits. The use of quebracho in the precipitation of germanium from zinc ores and for the recovery of ultrafine gold is also detailed in this work. This analysis explores the wide range of uses and methodology of quebracho in the extractive metallurgy field and expands on previous research by Iskra and Kitchener at Imperial College entitled, “Quebracho in Mineral Processing”.

  11. Native Language Processing using Exegy Text Miner

    Energy Technology Data Exchange (ETDEWEB)

    Compton, J

    2007-10-18

    Lawrence Livermore National Laboratory's New Architectures Testbed recently evaluated Exegy's Text Miner appliance to assess its applicability to high-performance, automated native language analysis. The evaluation was performed with support from the Computing Applications and Research Department in close collaboration with Global Security programs, and institutional activities in native language analysis. The Exegy Text Miner is a special-purpose device for detecting and flagging user-supplied patterns of characters, whether in streaming text or in collections of documents at very high rates. Patterns may consist of simple lists of words or complex expressions with sub-patterns linked by logical operators. These searches are accomplished through a combination of specialized hardware (i.e., one or more field-programmable gates arrays in addition to general-purpose processors) and proprietary software that exploits these individual components in an optimal manner (through parallelism and pipelining). For this application the Text Miner has performed accurately and reproducibly at high speeds approaching those documented by Exegy in its technical specifications. The Exegy Text Miner is primarily intended for the single-byte ASCII characters used in English, but at a technical level its capabilities are language-neutral and can be applied to multi-byte character sets such as those found in Arabic and Chinese. The system is used for searching databases or tracking streaming text with respect to one or more lexicons. In a real operational environment it is likely that data would need to be processed separately for each lexicon or search technique. However, the searches would be so fast that multiple passes should not be considered as a limitation a priori. Indeed, it is conceivable that large databases could be searched as often as necessary if new queries were deemed worthwhile. This project is concerned with evaluating the Exegy Text Miner installed in the

  12. Tannins in Mineral Processing and Extractive Metallurgy

    OpenAIRE

    2015-01-01

    This study provides an up to date review of tannins, specifically quebracho, in mineral processing and metallurgical processes. Quebracho is a highly useful reagent in many flotation applications, acting as both a depressant and a dispersant. Three different types of quebracho are mentioned in this study; quebracho “S” or Tupasol ATO, quebracho “O” or Tupafin ATO, and quebracho “A” or Silvafloc. It should be noted that literature often refers simply to “quebracho” without distinguishing a spe...

  13. Mineralization of Zein Films by Biomimetic Process

    Institute of Scientific and Technical Information of China (English)

    JIN Xiaoning; ZHANG Yanxiang; MA Ying; ZENG Sheng; WANG Shaozhen; MA Yalu

    2015-01-01

    The transparent or opaque zein film was prepared by a phase separation method with a zein ethanol aqueous solution. The circular zein film was self-assembled on the air-water interface. According to the images by scanning elec-tron microscopy, the upper surface of film is flat and smooth and the downward surface presents a complex reticulation structure of corn protein fiber. Zein film as a biomimetic mineralization template is used to synthesize calcium phosphate crystals by a bioinspired mineralization process. Randomly oriented apatite crystals appear on the both surfaces of zein film after immersion in 10´simulated body fluid, and the phase composition and morphology of the deposited calcium apatite are also distinguished from deposited location and immersion time. The phase transformation process from dical-cium phosphate dihydrate into hydroxyapatite (HAp) phase was investigated by X-ray powder diffraction, transmission electron microscopy and Fourier transform infrared spectroscopy, respectively. Based on the results by energy dispersive X-ray spectroscopy, the Ca/P ratio of the deposited apatite increases with the transformation from DCPD to HAp. The HAp/Zein films possess the excellent biodegradable structural features, and the coating of HAp crystallites has some potential applications for bone repair and regeneration.

  14. Mineralization of Zein Films by Biomimetic Process

    Institute of Scientific and Technical Information of China (English)

    JIN; Xiaoning; ZHANG; Yanxiang; MA; Ying; ZENG; Sheng; WANG; Shaozhen; MA; Yalu

    2015-01-01

    The transparent or opaque zein film was prepared by a phase separation method with a zein ethanol aqueous solution.The circular zein film was self-assembled on the air-water interface.According to the images by scanning electron microscopy,the upper surface of film is flat and smooth and the downward surface presents a complex reticulation structure of corn protein fiber.Zein film as a biomimetic mineralization template is used to synthesize calcium phosphate crystals by a bioinspired mineralization process.Randomly oriented apatite crystals appear on the both surfaces of zein film after immersion in lOxsimulated body fluid,and the phase composition and morphology of the deposited calcium apatite are also distinguished from deposited location and immersion time.The phase transformation process from dicalcium phosphate dihydrate into hydroxyapatite(HAp) phase was investigated by X-ray powder diffraction,transmission electron microscopy and Fourier transform infrared spectroscopy,respectively.Based on the results by energy dispersive X-ray spectroscopy,the Ca/P ratio of the deposited apatite increases with the transformation from DCPD to HAp.The HAp/Zein films possess the excellent biodegradable structural features,and the coating of HAp crystallites has some potential applications for bone repair and regeneration.

  15. Modern control of mineral wool production process

    Directory of Open Access Journals (Sweden)

    Stankov Stanko P.

    2013-01-01

    Full Text Available In this paper, the control of the plant for mineral wool production consisting of a number of the technological units of different sizes and complexity is considered. The application of modern equipment based on PLC (Programmable Logic Controller and SCADA (Supervisory Control And Data Acquisition configuration provides optimal control of technological process. Described supervisory and control system is consisting of a number of units doing decentralized distributed control of technological entities where all possible situation are considered during work of machines and devices, which are installed in electric drive and are protected from technological and electrical accident. Transformer station and diesel engine, raw materials transport and dosage, processes in dome oven, centrifuges, polycondensation (PC chamber, burners, compressor station, binder preparation and dosage, wool cutting, completed panel packing and their transport to storehouse are controlled. Process variables and parameters like as level, flow, velocity, temperature, pressure, etc. are controlled. Control system is doing identification of process states changes, diagnostic and prediction of errors and provides prediction of behavior of control objects when input flows of materials and generates optimal values of control variables due to decreasing downtime and technic - economical requires connected to wool quality to be achieved. Supervisory and control system either eliminates unwanted changes in the production line or restricts them within the allowable limits according to the technology. In this way, the optimization of energy and raw materials consumption and appropriate products quality is achieved, where requirements are satisfied in accordance with process safety and environmental standards. SCADA provides a visual representation of controlled and uncontrolled parts of the technological process, processing alarms and events, monitoring of the changes of relevant

  16. NEW PROGRESS IN MINERAL PROCESSING——REPORT ON FIRST INTERNATIONAL CONFERENCE ON MODERN PROCESS MINERALOGY AND MINERAL PROCESSING

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was held on September 22-25,1992,in Beijing,China.About 350 scholars and experts from 25 countries and regions showed up at the conference and 130 papers were presented,among them 98 papers are of mineral processing.Some of the papers given in mineral processing are summed up as follows.

  17. Sustainable Production Process of Biological Mineral Feed Additives

    OpenAIRE

    Agnieszka Zielinska; Katarzyna Chojnacka; Marjana Simonic

    2009-01-01

    Problem statement: This study discussed the problem of accumulation of Zn and Cu in the topsoil as a result of application of mineral feed additives that possess low bioavailability in animal diet. The review considered the production process of mineral feed additives in which a product supplies microelements in highly bioavailable form. Enrichment of natural biomass of edible microalgae with microelement metal ions, which supply microelements of feeding significance in livestock diet, is con...

  18. Pretreatment process for mineral analysis in FFH using INAA-method and evaluation of mineral intakes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ok Hee; Youn, Kyung Jin; Lee, Ji Bum; Kim, Mi Jin [Yongin University, Yongin (Korea, Republic of)

    2010-05-15

    This study were aimed to set up the pre-treatment process for FFH and analyse Pretreatment processes for the analysis of food mineral contents by INAA were established according to FFH state using freeze-drying and homogenization. The Se contents showed higher precision with INAA-method than ICP-method. The content of Ca, Na, Mg, Fe, Zn, Cu, Mn, Cr, Co in FFH measured using INAA-method showed that the mineral contents in the amount of recommended intakes by manufacturer were not significantly different according to FFH type. The average Ca contents was the highest in Yousanguns > nutritional supplement> glucosamines. The average K content of FFH with one serving size were the highest in glucosamines>aloes> nutritional supplements. I content among FFH was the highest in nutritional supplements. The average Mg contents were highest in Chlorella-Spirurina and Aloes. The average Cu content of FFH was the highest in Yeasts. The contents of Fe, Zn and Se were the highest in nutritional supplements. The mineral contents in recommended intake amounts by manufacturer were over the maximum contents regulated by Korean FDA in some imported FFH products. their mineral contents of FFH using NAA-method and to assess the mineral intakes by FFH

  19. The solubility of a metallic mineral with other coexisting minerals and the ore-forming processes of metallic sulfides

    Institute of Scientific and Technical Information of China (English)

    岑况; 於崇文

    2001-01-01

    Most metallic minerals in ore deposits are sulfides. When a sulfide mineral coexists with rock-forming minerals, its solubility is distinctly different from itself alone. The change in dissolution character of a mineral with coexisting rock-forming minerals leads to particular geochemical be-havior. The concept of solubility of a metallic mineral with coexisting rock-forming minerals and its theory and model of calculation are put forward. Taking Tianmashan Cu-Au ore deposit of sulfide minerals in Tongling district as an example, solubilities of some metallic minerals with other coex-isting minerals, such as pyrite or chalcopyrite with quartz (representing sandstone) or calcite (rep-resenting limestone), are calculated. The results show the mechanism of ore-forming processes. As the ore-forming fluid flows through sandstone, it dissolves pyrite in the sandstone at first, then transports the iron and sulfur to the interface between sandstone and limestone and eventually precipitates them on the interface.

  20. Agronomic potential of mineral concentrate from processed manure as fertiliser

    NARCIS (Netherlands)

    Velthof, G.L.; Hoeksma, P.; Schröder, J.J.; Middelkoop, van J.C.; Geel, van W.C.A.; Ehlert, P.A.I.; Holshof, G.; Klop, G.; Lesschen, J.P.

    2012-01-01

    Processing of manure intends to increase the use efficiency of nutrients. A concentrated solution of nitrogen (N) and potassium (K) (‘mineral concentrate’) is one of the possible products resulting from manure processing. A study is carried out in the Netherlands to determine the agronomic and envir

  1. Twenty bone-mineral-density loci identified by large-scale meta-analysis of genome-wide association studies.

    Science.gov (United States)

    Rivadeneira, Fernando; Styrkársdottir, Unnur; Estrada, Karol; Halldórsson, Bjarni V; Hsu, Yi-Hsiang; Richards, J Brent; Zillikens, M Carola; Kavvoura, Fotini K; Amin, Najaf; Aulchenko, Yurii S; Cupples, L Adrienne; Deloukas, Panagiotis; Demissie, Serkalem; Grundberg, Elin; Hofman, Albert; Kong, Augustine; Karasik, David; van Meurs, Joyce B; Oostra, Ben; Pastinen, Tomi; Pols, Huibert A P; Sigurdsson, Gunnar; Soranzo, Nicole; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Williams, Frances M K; Wilson, Scott G; Zhou, Yanhua; Ralston, Stuart H; van Duijn, Cornelia M; Spector, Timothy; Kiel, Douglas P; Stefansson, Kari; Ioannidis, John P A; Uitterlinden, André G

    2009-11-01

    Bone mineral density (BMD) is a heritable complex trait used in the clinical diagnosis of osteoporosis and the assessment of fracture risk. We performed meta-analysis of five genome-wide association studies of femoral neck and lumbar spine BMD in 19,195 subjects of Northern European descent. We identified 20 BMD loci that reached genome-wide significance (GWS; P GPR177), 2p21 (SPTBN1), 3p22 (CTNNB1), 4q21.1 (MEPE), 5q14 (MEF2C), 7p14 (STARD3NL), 7q21.3 (FLJ42280), 11p11.2 (LRP4, ARHGAP1, F2), 11p14.1 (DCDC5), 11p15 (SOX6), 16q24 (FOXL1), 17q21 (HDAC5) and 17q12 (CRHR1). The meta-analysis also confirmed at GWS level seven known BMD loci on 1p36 (ZBTB40), 6q25 (ESR1), 8q24 (TNFRSF11B), 11q13.4 (LRP5), 12q13 (SP7), 13q14 (TNFSF11) and 18q21 (TNFRSF11A). The many SNPs associated with BMD map to genes in signaling pathways with relevance to bone metabolism and highlight the complex genetic architecture that underlies osteoporosis and variation in BMD.

  2. The challenges of reusing mining and mineral-processing wastes.

    Science.gov (United States)

    Bian, Zhengfu; Miao, Xiexing; Lei, Shaogang; Chen, Shen-en; Wang, Wenfeng; Struthers, Sue

    2012-08-10

    Mining and mineral-processing wastes are one of the world's largest chronic waste concerns. Their reuse should be included in future sustainable development plans, but the potential impacts on a number of environmental processes are highly variable and must be thoroughly assessed. The chemical composition and geotechnical properties of the source rock determine which uses are most appropriate and whether reuse is economically feasible. If properly evaluated, mining waste can be reused to reextract minerals, provide additional fuel for power plants, supply construction materials, and repair surface and subsurface land structures altered by mining activities themselves.

  3. Mineral processing by short circuits in protoplanetary disks

    DEFF Research Database (Denmark)

    Mcnally, C.P.; Hubbard, A.; Mac Low, M.-M.

    2013-01-01

    the magnetic fields amplified by a disk dynamo. We suggest that it is possible to heat precursor grains for chondrules and other high-temperature minerals in current sheets that have been concentrated by our recently described short-circuit instability. We extend our work on this process by including...... global models. This mechanism could provide an efficient means of tapping the gravitational potential energy of the protoplanetary disk to heat grains strongly enough to form high-temperature minerals. The volume-filling nature of turbulent magnetic reconnection is compatible with constraints from...... chondrule-matrix complementarity, chondrule-chondrule complementarity, the occurrence of igneous rims, and compound chondrules. The same short-circuit mechanism may perform other high-temperature mineral processing in protoplanetary disks such as the production of crystalline silicates and CAIs....

  4. Minerals

    Directory of Open Access Journals (Sweden)

    Vaquero, M. P.

    1998-08-01

    Full Text Available The possible changes in the mineral composition of food during frying could be the consequence of losses by leaching, or changes in concentrations caused by exchanges between the food and culinary fat of other compounds. The net result depends on the type of food, the frying fat used and the frying process. Moreover, the modifications that frying produces in other nutrients could indirectly affect the availability of dietary minerals. The most outstanding ones are those that can take place in the fat or in the protein. With respect to the interactions between frying oils and minerals, we have recent knowledge concerning the effects of consuming vegetable oils used in repeated fryings of potatoes without turnover, on the nutritive utilization of dietary minerals. The experiments have been carried out in pregnant and growing rats, which consumed diets containing, as a sole source of fat, the testing frying oils or unused oils. It seems that the consumption of various frying oils, with a polar compound content lower or close to the maximum limit of 25% accepted for human consumption, does not alter the absorption and metabolism of calcium, phosphorous, iron or copper. Magnesium absorption from diets containing frying oils tends to increase but the urinary excretion of this element increases, resulting imperceptible the variations in the magnesium balance. The urinary excretion of Zn also increased although its balance remained unchanged. Different studies referring to the effects of consuming fried fatty fish on mineral bioavailability will also be presented. On one hand, frying can cause structural changes in fish protein, which are associated with an increase in iron absorption and a decrease in body zinc retention. The nutritive utilization of other elements such as magnesium, calcium and copper seems to be unaffected. On the other hand; it has been described that an excess of fish fatty acids in the diet produces iron depletion, but when fatty

  5. METALS LEACHING FROM A MINERAL PROCESSING WASTE: A COLUMN STUDY

    Science.gov (United States)

    A mineral processing waste was used to study the effect of liquid to solid ratio (L/S) on the leaching behavior of metals. Leaching tests in the form of column and batch studies were carried out to investigate liquid to solid ratios ranging from 0.7 to 50. Although the waste pass...

  6. Minerals processing opportunities for New South Wales and Australia

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, R. (Pasminco Mining, NSW (Australia))

    1991-03-01

    An account is given of the main findings and recommendations of a report presented in September 1990 by the NSW Task Force on Mineral Processing Development Strategies. The Task Force considered that the best opportunities fell into two categories: existing industries with development potential (steel, aluminium, refractories, zinc, lead, copper, coke, dimension stone and gemstones) and new opportunities (in processing of titanium, titanium dioxide pigment, rare earths, silicon, fused silica, advanced ceramics, mullite and magnesium). Potential for development of the minerals is discussed. Australia is seen as being in an excellent position to capitalize on recent economic changes and new technolgies. Coal, except for value-added coal products and petroleum were excluded from the study - a separate task force has been set up to consider the NSW coal industry. 1 ref., 2 figs., 1 tab.

  7. Natural radionuclide concentrations in processed materials from Thai mineral industries.

    Science.gov (United States)

    Chanyotha, S; Kranrod, C; Chankow, N; Kritsananuwat, R; Sriploy, P; Pangza, K

    2012-11-01

    The naturally occurring radioactive materials (NORMs) distributed in products, by-products and waste produced from Thai mineral industries were investigated. Samples were analysed for radioactivity concentrations of two principal NORM isotopes: (226)Ra and (228)Ra. The enrichment of NORM was found to occur during the treatment process of some minerals. The highest activity of (226)Ra (7 × 10(7) Bq kg(-1)) was in the scale from tantalum processing. The radium concentration in the discarded by-product material from metal ore dressing was also enriched by 3-10 times. Phosphogypsum, a waste produced from the production of phosphate fertilisers, contained 700 times the level of (226)Ra concentration found in phosphate ore. Hence, these residues were also sources of exposure to workers and the public, which needed to be controlled.

  8. Microwave processing of oil sands and contribution of clay minerals

    OpenAIRE

    John P. Robinson; Binner, Eleanor; Saeid, Abdul; Al-Harahsheh, Mohammad; Kingman, S. W.

    2014-01-01

    This study establishes the feasibility of microwave heating for extracting oil from Oil Sands in ex-situ processes. Previous studies in this area have shown some potential, but have not characterised the dielectric properties of the Oil Sands used, nor related them to the mineral composition, both of which are vital if successful scale up is to be achieved. In this work the fundamental interactions of microwave energy with Oil Sands are investigated and understood for the first time, and the ...

  9. Sustainable Production Process of Biological Mineral Feed Additives

    Directory of Open Access Journals (Sweden)

    Agnieszka Zielinska

    2009-01-01

    Full Text Available Problem statement: This study discussed the problem of accumulation of Zn and Cu in the topsoil as a result of application of mineral feed additives that possess low bioavailability in animal diet. The review considered the production process of mineral feed additives in which a product supplies microelements in highly bioavailable form. Enrichment of natural biomass of edible microalgae with microelement metal ions, which supply microelements of feeding significance in livestock diet, is considered in term of sustainable production. Approach: Production of microalgae-derived products as mineral feed additives requires elaboration of the processes for cultivation of alga, enrichment process and afterwards recovery of the enriched biomass from the solution to obtain liquid free of cells that could be reused in the next process. In this study membrane bioreactor was considered as a method for separation, both in photobioreactor (growth of microorganism as well as in the enrichment process. Results: Effort involved in thermal and chemical separation techniques is higher than that in mechanical techniques. Membrane bioreactors which are usually applied to treat wastewater, both industrial and domestic. This study discussed method to separate a valuable biomass of enriched microalgae and reuse the solution with residual metal ions that can be used once again in the subsequent biosorption process. Conclusion/Recommendation: Taking into consideration care about the environment it is better to apply membrane modules in the production process in terms of sustainable production. The proposed solution assumed the application of membrane modules as a separation step after enrichment process and biomass recovery.

  10. Copper isotopes as monitors of redox processes in hydrothermal mineralization

    Science.gov (United States)

    Markl, Gregor; Lahaye, Yann; Schwinn, Gregor

    2006-08-01

    The stable copper isotope composition of 79 samples of primary and secondary copper minerals from hydrothermal veins in the Schwarzwald mining district, South Germany, shows a wide variation in δ65Cu ranging from -2.92 to 2.41‰. We investigated primary chalcopyrite, various kinds of fahlores and emplectite, as well as supergene native copper, malachite, azurite, cuprite, tenorite, olivenite, pseudomalachite and chrysocolla. Fresh primary Cu(I) ores have at most localities copper isotope ratios ( δ65Cu values) of 0 ± 0.5‰ despite the fact that the samples come from mineralogically different types of deposits covering an area of about 100 by 50 km and that they formed during three different mineralization events spanning the last 300 Ma. Relics of the primary ores in oxidized samples (i.e., chalcopyrite relics in an iron oxide matrix with an outer malachite coating) display low isotope ratios down to -2.92‰. Secondary Cu(I) minerals such as cuprite have high δ65Cu values between 0.4 and 1.65‰, whereas secondary Cu(II) minerals such as malachite show a range of values between -1.55 and 2.41‰, but typically have values above +0.5‰. Within single samples, supergene oxidation of fresh chalcopyrite with a δ value of 0‰ causes significant fractionation on the scale of a centimetre between malachite (up to 1.49‰) and relict chalcopyrite (down to -2.92‰). The results show that—with only two notable exceptions—high-temperature hydrothermal processes did not lead to significant and correlatable variations in copper isotope ratios within a large mining district mineralized over a long period of time. Conversely, low-temperature redox processes seriously affect the copper isotope compositions of hydrothermal copper ores. While details of the redox processes are not yet understood, we interpret the range in compositions found in both primary Cu(I) and secondary Cu(II) minerals as a result of two competing controls on the isotope fractionation process

  11. Asporin and the mineralization process in fluoride-treated rats.

    Science.gov (United States)

    Houari, Sophia; Wurtz, Tilmann; Ferbus, Didier; Chateau, Danielle; Dessombz, Arnaud; Berdal, Ariane; Babajko, Sylvie

    2014-06-01

    Microarray analysis of odontoblastic cells treated with sodium fluoride has identified the asporin gene as a fluoride target. Asporin is a member of the small leucine-rich repeat proteoglycan/protein (SLRP) family that is believed to be important in the mineralization process. In this study, asporin expression and distribution were investigated by systematic analysis of dentin and enamel, with and without fluoride treatment. Specific attention was focused on a major difference between the two mineralized tissues: the presence of a collagenous scaffold in dentin, and its absence in enamel. Normal and fluorotic, continually growing incisors from Wistar rats treated with 2.5 to 7.5 mM sodium fluoride (NaF) were studied by immunochemistry, in situ hybridization, Western blotting, and RT-qPCR. Asporin was continuously expressed in odontoblasts throughout dentin formation as expected. Asporin was also found, for the first time, in dental epithelial cells, particularly in maturation-stage ameloblasts. NaF decreased asporin expression in odontoblasts and enhanced it in ameloblasts, both in vivo and in vitro. The inverse response in the two cell types suggests that the effector, fluoride, is a trigger that elicits a cell-type-specific reaction. Confocal and ultrastructural immunohistochemistry evidenced an association between asporin and type 1 collagen in the pericellular nonmineralized compartments of both bone and dentin. In addition, transmission electron microscopy revealed asporin in the microenvironment of all cells observed. Thus, asporin is produced by collagen-matrix-forming and non-collagen-matrix-forming cells but may have different effects on the mineralization process. A model is proposed that predicts impaired mineral formation associated with the deficiency and excess of asporin.

  12. Twenty-first century science as a relational process: from eureka! to team science and a place for community psychology.

    Science.gov (United States)

    Tebes, Jacob Kraemer; Thai, Nghi D; Matlin, Samantha L

    2014-06-01

    In this paper we maintain that twenty-first century science is, fundamentally, a relational process in which knowledge is produced (or co-produced) through transactions among researchers or among researchers and public stakeholders. We offer an expanded perspective on the practice of twenty-first century science, the production of scientific knowledge, and what community psychology can contribute to these developments. We argue that: (1) trends in science show that research is increasingly being conducted in teams; (2) scientific teams, such as transdisciplinary teams of researchers or of researchers collaborating with various public stakeholders, are better able to address complex challenges; (3) transdisciplinary scientific teams are part of the larger, twenty-first century transformation in science; (4) the concept of heterarchy is a heuristic for team science aligned with this transformation; (5) a contemporary philosophy of science known as perspectivism provides an essential foundation to advance twenty-first century science; and (6) community psychology, through its core principles and practice competencies, offers theoretical and practical expertise for advancing team science and the transformation in science currently underway. We discuss the implications of these points and illustrate them briefly with two examples of transdisciplinary team science from our own work. We conclude that a new narrative is emerging for science in the twenty-first century that draws on interpersonal transactions in teams, and active engagement by researchers with the public to address critical accountabilities. Because of its core organizing principles and unique blend of expertise on the intersection of research and practice, community psychologists are well-prepared to help advance these developments, and thus have much to offer twenty-first century science.

  13. MINERAL PROCESSING BY SHORT CIRCUITS IN PROTOPLANETARY DISKS

    Energy Technology Data Exchange (ETDEWEB)

    McNally, Colin P. [Niels Bohr International Academy, Niels Bohr Institute, DK-2100 Copenhagen (Denmark); Hubbard, Alexander; Mac Low, Mordecai-Mark [Department of Astrophysics, American Museum of Natural History, New York, NY 10024-5192 (United States); Ebel, Denton S. [Department of Earth and Planetary Sciences, American Museum of Natural History, New York, NY 10024-5192 (United States); D' Alessio, Paola, E-mail: cmcnally@nbi.dk, E-mail: ahubbard@amnh.org, E-mail: mordecai@amnh.org, E-mail: debel@amnh.org, E-mail: p.dalessio@crya.unam.mx [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, 58089 Morelia, MICH (Mexico)

    2013-04-10

    Meteoritic chondrules were formed in the early solar system by brief heating of silicate dust to melting temperatures. Some highly refractory grains (Type B calcium-aluminum-rich inclusions, CAIs) also show signs of transient heating. A similar process may occur in other protoplanetary disks, as evidenced by observations of spectra characteristic of crystalline silicates. One possible environment for this process is the turbulent magnetohydrodynamic flow thought to drive accretion in these disks. Such flows generally form thin current sheets, which are sites of magnetic reconnection, and dissipate the magnetic fields amplified by a disk dynamo. We suggest that it is possible to heat precursor grains for chondrules and other high-temperature minerals in current sheets that have been concentrated by our recently described short-circuit instability. We extend our work on this process by including the effects of radiative cooling, taking into account the temperature dependence of the opacity; and by examining current sheet geometry in three-dimensional, global models of magnetorotational instability. We find that temperatures above 1600 K can be reached for favorable parameters that match the ideal global models. This mechanism could provide an efficient means of tapping the gravitational potential energy of the protoplanetary disk to heat grains strongly enough to form high-temperature minerals. The volume-filling nature of turbulent magnetic reconnection is compatible with constraints from chondrule-matrix complementarity, chondrule-chondrule complementarity, the occurrence of igneous rims, and compound chondrules. The same short-circuit mechanism may perform other high-temperature mineral processing in protoplanetary disks such as the production of crystalline silicates and CAIs.

  14. A Novel Approach to Mineral Carbonation: Enhancing Carbonation While Avoiding Mineral Pretreatment Process Cost

    Energy Technology Data Exchange (ETDEWEB)

    Andrew V. G. Chizmeshya; Michael J. McKelvy; Kyle Squires; Ray W. Carpenter; Hamdallah Bearat

    2007-06-21

    Known fossil fuel reserves, especially coal, can support global energy demands for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Unlike other CO{sub 2} sequestration candidate technologies that propose long-term storage, mineral sequestration provides permanent disposal by forming geologically stable mineral carbonates. Carbonation of the widely occurring mineral olivine (e.g., forsterite, Mg{sub 2}SiO{sub 4}) is a large-scale sequestration process candidate for regional implementation, which converts CO{sub 2} into the environmentally benign mineral magnesite (MgCO{sub 3}). The primary goal is cost-competitive process development. As the process is exothermic, it inherently offers low-cost potential. Enhancing carbonation reactivity is key to economic viability. Recent studies at the U.S. DOE Albany Research Center have established that aqueous-solution carbonation using supercritical CO{sub 2} is a promising process; even without olivine activation, 30-50% carbonation has been achieved in an hour. Mechanical activation (e.g., attrition) has accelerated the carbonation process to an industrial timescale (i.e., near completion in less than an hour), at reduced pressure and temperature. However, the activation cost is too high to be economical and lower cost pretreatment options are needed. We have discovered that robust silica-rich passivating layers form on the olivine surface during carbonation. As carbonation proceeds, these passivating layers thicken, fracture and eventually exfoliate, exposing fresh olivine surfaces during rapidly-stirred/circulating carbonation. We are exploring the mechanisms that govern carbonation reactivity and the impact that (1) modeling/controlling the slurry fluid-flow conditions, (2) varying the aqueous ion species/size and concentration (e.g., Li+, Na+, K+, Rb+, Cl-, HCO{sub 3}{sup -}), and (3) incorporating select sonication offer to enhance exfoliation and carbonation. Thus

  15. A Novel Approach To Mineral Carbonation: Enhancing Carbonation While Avoiding Mineral Pretreatment Process Cost

    Energy Technology Data Exchange (ETDEWEB)

    Michael J. McKelvy; Andrew V. G. Chizmeshya; Kyle Squires; Ray W. Carpenter; Hamdallah Bearat

    2006-06-21

    Known fossil fuel reserves, especially coal, can support global energy demands for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Unlike other CO{sub 2} sequestration candidate technologies that propose long-term storage, mineral sequestration provides permanent disposal by forming geologically stable mineral carbonates. Carbonation of the widely occurring mineral olivine (e.g., forsterite, Mg{sub 2}SiO{sub 4}) is a large-scale sequestration process candidate for regional implementation, which converts CO{sub 2} into the environmentally benign mineral magnesite (MgCO{sub 3}). The primary goal is cost-competitive process development. As the process is exothermic, it inherently offers low-cost potential. Enhancing carbonation reactivity is key to economic viability. Recent studies at the U.S. DOE Albany Research Center have established that aqueous-solution carbonation using supercritical CO{sub 2} is a promising process; even without olivine activation, 30-50% carbonation has been achieved in an hour. Mechanical activation (e.g., attrition) has accelerated the carbonation process to an industrial timescale (i.e., near completion in less than an hour), at reduced pressure and temperature. However, the activation cost is too high to be economical and lower cost pretreatment options are needed. Herein, we report our second year progress in exploring a novel approach that offers the potential to substantially enhance carbonation reactivity while bypassing pretreatment activation. As our second year progress is intimately related to our earlier work, the report is presented in that context to provide better overall understanding of the progress made. We have discovered that robust silica-rich passivating layers form on the olivine surface during carbonation. As carbonation proceeds, these passivating layers thicken, fracture and eventually exfoliate, exposing fresh olivine surfaces during rapidly

  16. A Novel Approach To Mineral Carbonation: Enhancing Carbonation While Avoiding Mineral Pretreatment Process Cost

    Energy Technology Data Exchange (ETDEWEB)

    Michael J. McKelvy; Andrew V. G. Chizmeshya; Kyle Squires; Ray W. Carpenter; Hamdallah Bearat

    2006-06-21

    Known fossil fuel reserves, especially coal, can support global energy demands for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Unlike other CO{sub 2} sequestration candidate technologies that propose long-term storage, mineral sequestration provides permanent disposal by forming geologically stable mineral carbonates. Carbonation of the widely occurring mineral olivine (e.g., forsterite, Mg{sub 2}SiO{sub 4}) is a large-scale sequestration process candidate for regional implementation, which converts CO{sub 2} into the environmentally benign mineral magnesite (MgCO{sub 3}). The primary goal is cost-competitive process development. As the process is exothermic, it inherently offers low-cost potential. Enhancing carbonation reactivity is key to economic viability. Recent studies at the U.S. DOE Albany Research Center have established that aqueous-solution carbonation using supercritical CO{sub 2} is a promising process; even without olivine activation, 30-50% carbonation has been achieved in an hour. Mechanical activation (e.g., attrition) has accelerated the carbonation process to an industrial timescale (i.e., near completion in less than an hour), at reduced pressure and temperature. However, the activation cost is too high to be economical and lower cost pretreatment options are needed. Herein, we report our second year progress in exploring a novel approach that offers the potential to substantially enhance carbonation reactivity while bypassing pretreatment activation. As our second year progress is intimately related to our earlier work, the report is presented in that context to provide better overall understanding of the progress made. We have discovered that robust silica-rich passivating layers form on the olivine surface during carbonation. As carbonation proceeds, these passivating layers thicken, fracture and eventually exfoliate, exposing fresh olivine surfaces during rapidly

  17. A Novel Approach to Mineral Carbonation: Enhancing Carbonation While Avoiding Mineral Pretreatment Process Cost

    Energy Technology Data Exchange (ETDEWEB)

    Andrew V. G. Chizmeshya; Michael J. McKelvy; Kyle Squires; Ray W. Carpenter; Hamdallah Bearat

    2007-06-21

    Known fossil fuel reserves, especially coal, can support global energy demands for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Unlike other CO{sub 2} sequestration candidate technologies that propose long-term storage, mineral sequestration provides permanent disposal by forming geologically stable mineral carbonates. Carbonation of the widely occurring mineral olivine (e.g., forsterite, Mg{sub 2}SiO{sub 4}) is a large-scale sequestration process candidate for regional implementation, which converts CO{sub 2} into the environmentally benign mineral magnesite (MgCO{sub 3}). The primary goal is cost-competitive process development. As the process is exothermic, it inherently offers low-cost potential. Enhancing carbonation reactivity is key to economic viability. Recent studies at the U.S. DOE Albany Research Center have established that aqueous-solution carbonation using supercritical CO{sub 2} is a promising process; even without olivine activation, 30-50% carbonation has been achieved in an hour. Mechanical activation (e.g., attrition) has accelerated the carbonation process to an industrial timescale (i.e., near completion in less than an hour), at reduced pressure and temperature. However, the activation cost is too high to be economical and lower cost pretreatment options are needed. We have discovered that robust silica-rich passivating layers form on the olivine surface during carbonation. As carbonation proceeds, these passivating layers thicken, fracture and eventually exfoliate, exposing fresh olivine surfaces during rapidly-stirred/circulating carbonation. We are exploring the mechanisms that govern carbonation reactivity and the impact that (1) modeling/controlling the slurry fluid-flow conditions, (2) varying the aqueous ion species/size and concentration (e.g., Li+, Na+, K+, Rb+, Cl-, HCO{sub 3}{sup -}), and (3) incorporating select sonication offer to enhance exfoliation and carbonation. Thus

  18. Mineralization of the biocide chloroxylenol by electrochemical advanced oxidation processes.

    Science.gov (United States)

    Skoumal, Marcel; Arias, Conchita; Cabot, Pere Lluís; Centellas, Francesc; Garrido, José Antonio; Rodríguez, Rosa María; Brillas, Enric

    2008-04-01

    Electrochemical advanced oxidation processes (EAOPs) are environmentally friendly methods based on the destruction of organic pollutants in wastewaters with in situ electrogenerated hydroxyl radical. This species is formed in anodic oxidation (AO) from water oxidation at the anode and in indirect electro-oxidation methods like electro-Fenton (EF) and photoelectro-Fenton (PEF) also from reaction between catalytic Fe2+ and H2O2 continuously produced at the O2-diffusion cathode. The PEF method involves the irradiation of the treated solution with UVA light to enhance the photolysis of organics including Fe(III) complexes. In this work, the oxidation power of such EAOPs to decontaminate synthetic wastewaters of the biocide chloroxylenol (4-chloro-3,5-dimethylphenol) at pH 3.0 is comparatively examined with an undivided electrolytic cell containing a Pt or boron-doped diamond (BDD) anode and a stainless steel or O2-diffusion cathode. The initial chlorine is released as Cl(-) ion, which remains stable in the medium using Pt or is oxidized to Cl2 on BDD. The biocide solutions can be completely decontaminated using AO with a BDD anode, as well as PEF with a Pt or BDD anode. The PEF procedure with a BDD anode is the most powerful method leading to total mineralization in about 300 min, practically independent of current density. When current density rises, the degradation rate of processes increases, but they become less efficient due to the larger enhancement of waste reactions of oxidants. Chloroxylenol is much more rapidly removed in EF and PEF than in AO. 2,6-dimethylhydroquinone, 2,6-dimethyl-p-benzoquinone and 3,5-dimethyl-2-hydroxy-p-benzoquinone are identified as aromatic by-products, and maleic, malonic, pyruvic, acetic and oxalic acids are found as generated carboxylic acids. A general pathway for chloroxylenol mineralization by all EAOPs including the above by-products is proposed.

  19. Landmarks in the historical development of twenty first century food processing technologies.

    Science.gov (United States)

    Misra, N N; Koubaa, Mohamed; Roohinejad, Shahin; Juliano, Pablo; Alpas, Hami; Inácio, Rita S; Saraiva, Jorge A; Barba, Francisco J

    2017-07-01

    Over a course of centuries, various food processing technologies have been explored and implemented to provide safe, fresher-tasting and nutritive food products. Among these technologies, application of emerging food processes (e.g., cold plasma, pressurized fluids, pulsed electric fields, ohmic heating, radiofrequency electric fields, ultrasonics and megasonics, high hydrostatic pressure, high pressure homogenization, hyperbaric storage, and negative pressure cavitation extraction) have attracted much attention in the past decades. This is because, compared to their conventional counterparts, novel food processes allow a significant reduction in the overall processing times with savings in energy consumption, while ensuring food safety, and ample benefits for the industry. Noteworthily, industry and university teams have made extensive efforts for the development of novel technologies, with sound scientific knowledge of their effects on different food materials. The main objective of this review is to provide a historical account of the extensive efforts and inventions in the field of emerging food processing technologies since their inception to present day. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Separation of metals from incineration wastes using mineral industry processes

    Energy Technology Data Exchange (ETDEWEB)

    Scheizer, G. [Universite de Technologie, Aix-la-Chapelle (Germany)

    1996-12-01

    The incineration of municipal wastes in Federal Republic of Germany produced about 2.7 to 2.8 millions of tons of solid wastes in 1993 which still contain huge amounts of mineral and organic pollutants. Ashes represent the largest part of wastes with about 2.4 millions of tons. Vitrification is an innovative treatment technique which allows a 90% reduction of the waste volume, the complete removal of the organic matter content, and the storage of these waste in an environmentally neutral form. However, metals must be extracted from the ashes prior to the vitrification process. Most metals fall into the 2.4-2.7 g/cm{sup 3} and > 3 g/cm{sup 3} density ranges. The lighter fraction corresponds to aluminium particles and alloys, while the high density fraction is enriched in copper, copper alloys and more particularly in brass. The treatment process, after drying, consist in the use of high intensity magnetic separation devices (permanent neodymium-bore-iron magnets) for the removal of ferrous particles, and in the use of Foucault currents separation devices for non-magnetic metals. At the pilot-scale, the distribution of the processed wastes corresponds to: 62.6 % of non-metallized ashes, 35.5 % of magnetic products, and 1.9% of non-magnetic products. The possible recycling of the metal fraction must be demonstrated by further studies. (J.S.). Abstract only.

  1. Physics and chemistry of minerals under laser processing

    Science.gov (United States)

    Kotova, O.; Leonenko, N.

    2016-04-01

    New experimental data of the influence of laser irradiation on the phase composition minerals of bauxite and red mud and their technological features have been represented. The mechanisms of formation of micro- and nanophases on mineral surfaces under the influence of laser irradiation were shown. It is underlined that changes of condition of surface atoms, concentration of metals, agglomeration of titanium minerals and new phase formation occurred under laser irradiation on bauxites and red mud.

  2. Bibliography of articles and reports on mineral-separation techniques, processes, and applications

    Science.gov (United States)

    Harmon, R. S.

    1971-01-01

    A bibliography of published articles and reports on mineral-separation techniques, processes, and applications is presented along with an author and subject index. This information is intended for use in the mineral-separation facility of the Lunar Receiving Laboratory at the NASA Manned Spacecraft Center and as an aid and reference to persons involved or interested in mineral separation.

  3. The beginnings of mineral processing research in Canada (part 3)

    Energy Technology Data Exchange (ETDEWEB)

    Habashi, F. [Laval Univ., Quebec City, PQ (Canada). Dept. of Mining, Metallurgical and Materials Engineering

    2010-03-15

    This article presented the historical aspects regarding Canadian research in mineral processing and ore refining. It highlighted the career of Eugene Haanel, the first director of Canada's Department of Mines. The events that led to the creation of the Canadian Bureau of Mines and the Energy Branch at the turn of the 1900s were described along with the creation of the first assay office to deal with the large amounts of gold produced in British Columbia and the Yukon. In order to encourage the exploitation of Canada's iron ore deposits and the abundant electrical energy from Niagara Falls, Haanel organized a mission to Europe to study steel production using electric furnaces. He sought ways to secure a supply of the reducing agent and the fuel that metallurgical processes required in great quantities. Noting that Canada was spending millions to import coal and coke, he promoted the exploitation of the large deposits of peat in Ontario and Quebec. He also drew attention to the need to stop using wood as a fuel to conserve the forests. In 1905, the Mining Section was commissioned to evaluate nonferrous metal deposits in Canada, including lead-zinc, cobalt, asbestos, mica, graphite and raw materials for cement manufacture. Serious hydrometallurgical research in Canada began in 1921 at the Ministry of Mines, followed by pyrometallurgical research in 1922. The radioactivity division was created in 1948. The article also described the reorganization of extractive metallurgical research in Canada. 9 figs.

  4. REACTIVE MINERALS IN AQUIFERS: FORMATION PROCESSES AND QUANTITATIVE ANALYSIS

    Science.gov (United States)

    The presentation will focus on the occurrence, form, and characterization of reactive iron minerals in aquifers and soils. The potential for abiotic reductive transformations of contaminants at the mineral-water interface will be discussed along with available tools for site min...

  5. Twenty Years After Genocide: The Role of Psychology in the Reconciliation and Reconstruction Process in Rwanda

    Directory of Open Access Journals (Sweden)

    Craig McGarty

    2014-12-01

    Full Text Available This Special Thematic Section brings together eight papers that showcase different aspects of the contribution of psychology to the processes of recovery in Rwanda following the 1994 genocide. The Section is noteworthy in part because a majority of the papers have Rwandan authors. In summarizing the contributions I make six observations about the remarkable context of the genocide and its aftermath: a it was distinctive from previous mass violence in its intensity and character; b it has been characterized by bystander inaction and the problems of positioning outsiders to help; c hundreds of thousands of accused or convicted perpetrators have lived alongside survivors; d electronic media played a profound role not only in promoting violence but also in building peace; e Rwanda has been the site of unprecedented societal interventions with political goals that have the character and content of social psychological experiments; and f the role of memorialization in repairing or sustaining harm needs further examination. I conclude by noting that the study of recovery is clear proof that the genocide in Rwanda, as is the case with genocides of the past, failed to achieve its aims.

  6. Direct observations of the atmospheric processing of Asian mineral dust

    Directory of Open Access Journals (Sweden)

    R. C. Sullivan

    2007-01-01

    Full Text Available The accumulation of secondary acids and ammonium on individual mineral dust particles during ACE-Asia has been measured with an online single-particle mass spectrometer, the ATOFMS. Changes in the amounts of sulphate, nitrate, and chloride mixed with dust particles correlate with air masses from different source regions. The uptake of secondary acids depended on the individual dust particle mineralogy; high amounts of nitrate accumulated on calcium-rich dust while high amounts of sulphate accumulated on aluminosilicate-rich dust. Oxidation of S(IV to S(VI by iron in the aluminosilicate dust is a possible explanation for this enrichment of sulphate, which has important consequences for the fertilization of remote oceans by soluble iron. This study shows the segregation of sulphate from nitrate and chloride in individual aged dust particles for the first time. A transport and aging timeline provides an explanation for the observed segregation. Our data suggests that sulphate became mixed with the dust first. This implies that the transport pathway is more important than the reaction kinetics in determining which species accumulate on mineral dust. Early in the study, dust particles in volcanically influenced air masses were mixed predominately with sulphate. Dust mixed with chloride then dominated over sulphate and nitrate when a major dust front reached the R. V. Ronald Brown. We hypothesize that the rapid increase in chloride on dust was due to mixing with HCl(g released from acidified sea salt particles induced by heterogeneous reaction with volcanic SO2(g, prior to the arrival of the dust front. The amount of ammonium mixed with dust correlated strongly with the total amount of secondary acid reaction products in the dust. Submicron dust and ammonium sulphate were internally mixed, contrary to frequent reports that they exist as external mixtures. The size distribution of the mixing state of dust with these secondary species validates previous

  7. Innovation processes in technologies for the processing of refractory mineral raw materials

    Science.gov (United States)

    Chanturiya, V. A.

    2008-12-01

    Analysis of the grade of mineral resources of Russia and other countries shows that end products that are competitive in terms of both technological and environmental criteria in the world market can only be obtained by the development and implementation of progressive technologies based on the up-to-date achievements of fundamental sciences. The essence of modern innovation processes in technologies developed in Russia for the complex and comprehensive processing of refractory raw materials with a complex composition is ascertained. These processes include (i) radiometric methods of concentration of valuable components, (ii) high-energy methods of disintegration of highly dispersed mineral components, and (iii) electrochemical methods of water conditioning to obtain target products for solving specific technological problems.

  8. Understanding processes affecting mineral deposits in humid environments

    Science.gov (United States)

    Seal, Robert R., II; Ayuso, Robert A.

    2011-01-01

    Recent interdisciplinary studies by the U.S. Geological Survey have resulted in substantial progress toward understanding the influence that climate and hydrology have on the geochemical signatures of mineral deposits and the resulting mine wastes in the eastern United States. Specific areas of focus include the release, transport, and fate of acid, metals, and associated elements from inactive mines in temperate coastal areas and of metals from unmined mineral deposits in tropical to subtropical areas; the influence of climate, geology, and hydrology on remediation options for abandoned mines; and the application of radiogenic isotopes to uniquely apportion source contributions that distinguish natural from mining sources and extent of metal transport. The environmental effects of abandoned mines and unmined mineral deposits result from a complex interaction of a variety of chemical and physical factors. These include the geology of the mineral deposit, the hydrologic setting of the mineral deposit and associated mine wastes, the chemistry of waters interacting with the deposit and associated waste material, the engineering of a mine as it relates to the reactivity of mine wastes, and climate, which affects such factors as temperature and the amounts of precipitation and evapotranspiration; these factors, in turn, influence the environmental behavior of mineral deposits. The role of climate is becoming increasingly important in environmental investigations of mineral deposits because of the growing concerns about climate change.

  9. Mineral processing techniques for recycling investment casting shell

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, Cheryl L.; Nilsen, David N.; Dahlin, David C.; Hunt, Alton H.; Collins, W. Keith

    2002-01-01

    The Albany Research Center of the U.S. Department of Energy used materials characterization and minerals beneficiation methods to separate and beneficially modify spent investment-mold components to identify recycling opportunities and minimize environmentally sensitive wastes. The physical and chemical characteristics of the shell materials were determined and used to guide bench-scale research to separate reusable components by mineral-beneficiation techniques. Successfully concentrated shell materials were evaluated for possible use in new markets.

  10. Principles of image processing in machine vision systems for the color analysis of minerals

    Science.gov (United States)

    Petukhova, Daria B.; Gorbunova, Elena V.; Chertov, Aleksandr N.; Korotaev, Valery V.

    2014-09-01

    At the moment color sorting method is one of promising methods of mineral raw materials enrichment. This method is based on registration of color differences between images of analyzed objects. As is generally known the problem with delimitation of close color tints when sorting low-contrast minerals is one of the main disadvantages of color sorting method. It is can be related with wrong choice of a color model and incomplete image processing in machine vision system for realizing color sorting algorithm. Another problem is a necessity of image processing features reconfiguration when changing the type of analyzed minerals. This is due to the fact that optical properties of mineral samples vary from one mineral deposit to another. Therefore searching for values of image processing features is non-trivial task. And this task doesn't always have an acceptable solution. In addition there are no uniform guidelines for determining criteria of mineral samples separation. It is assumed that the process of image processing features reconfiguration had to be made by machine learning. But in practice it's carried out by adjusting the operating parameters which are satisfactory for one specific enrichment task. This approach usually leads to the fact that machine vision system unable to estimate rapidly the concentration rate of analyzed mineral ore by using color sorting method. This paper presents the results of research aimed at addressing mentioned shortcomings in image processing organization for machine vision systems which are used to color sorting of mineral samples. The principles of color analysis for low-contrast minerals by using machine vision systems are also studied. In addition, a special processing algorithm for color images of mineral samples is developed. Mentioned algorithm allows you to determine automatically the criteria of mineral samples separation based on an analysis of representative mineral samples. Experimental studies of the proposed algorithm

  11. Semi-empirical versus process-based sea-level projections for the twenty-first century

    Science.gov (United States)

    Orlić, Mirko; Pasarić, Zoran

    2013-08-01

    Two dynamical methods are presently used to project sea-level changes during the next century. The process-based method relies on coupled atmosphere-ocean models to estimate the effects of thermal expansion and on sea-level models combined with certain empirical relationships to determine the influence of land-ice mass changes. The semi-empirical method uses various physically motivated relationships between temperature and sea level, with parameters determined from the data, to project total sea level. However, semi-empirical projections far exceed process-based projections. Here, we test the robustness of semi-empirical projections to the underlying assumptions about the inertial and equilibrium responses of sea level to temperature forcing and the impacts of groundwater depletion and dam retention during the twentieth century. Our results show that these projections are sensitive to the dynamics considered and the terrestrial-water corrections applied. For B1, which is a moderate climate-change scenario, the lowest semi-empirical projection of sea-level rise over the twenty-first century equals 62+/-14cm. The average value is substantially smaller than previously published semi-empirical projections and is therefore closer to the corresponding process-based values. The standard deviation is larger than the uncertainties of process-based estimates.

  12. Iron isotope constraints on the mineralization processes of the Sandaowanzi telluride gold deposit, NE China

    Science.gov (United States)

    Li, Xingxing; Liu, Junlai; Lu, Di; Ren, Shunli; Liu, Zhengyang

    2016-04-01

    Iron isotopes have been widely applied to interpret the fluid evolution, supergene alteration and the metallogenic material sources of the hydrothermal deposit. It may also have significant potentials on the research of the deposit. The Sandaowanzi telluride gold deposit, located in the Great Hinggan Range metallogenic Belt in NE China, is a large epithermal gold deposit of low-sulphidation type. It has a total reserve of ≥25t of Au and an average of 15 g/t. Gold-bearing quartz veins or gold lodes strike to the NW and dip 50-80°northeastward. Ore bodies, including low-grade ores along margins and high-grade ores in the central parts, principally occur in quartz veins. More than the 95 percent Au budgets are hosted in gold-silver tellurides. A six-stage paragenetic sequence of mineralization is revealed according to the compositions and microstructures of the mineral assemblages. Although sulfide minerals in the bonanza quartz veins are rare, pyrite are widespread in quartz veins and altered host rocks. Meanwhile there are always chalcopyrite veins within bonanza quartz veins. Pyrite Fe isotope compositions from different levels (from +50m to +210m) of the main ore body of the Sandaowanzi gold ore deposit are investigated. There is an overall variation in δ57Fe values from -0.09 to +0.99 (av. 0.33). Among them, twenty three samples from different mining levels give positiveδ57Fe values, with the maximum positive value at the economic bonanza ores (level +130m). Four samples, however, possess negative values, one at level 170m, one at level 130m, and two at level 50m, respectively. The two negative values from the levels 170m and 130m are near the cores of the high grade ore body. The two negative values from the level 50m occur at one end of the lode ore body. The above data set shows that the δ57Fe values are not homogeneous at different levels of the ore body. On the other hand, a general trend for the positive values is that the highest δ57Fe value is

  13. Advances in microbial leaching processes for nickel extraction from lateritic minerals - A review

    Energy Technology Data Exchange (ETDEWEB)

    Behra, Sunil Kumar; Mulaba-Bafubiandi, Antoine Floribert [Faculty of Engineering and the Built Environment, University of Johannesburg, (South Africa)

    2015-08-15

    Lateritic nickel minerals constitute about 80% of nickel reserves in the world, but their contribution for nickel production is about 40%. The obstacles in extraction of nickel from lateritic minerals are attributed to their very complex mineralogy and low nickel content. Hence, the existing metallurgical techniques are not techno-economically feasible and environmentally sustainable for processing of such complex deposits. At this juncture, microbial mineral processing could be a benevolent approach for processing of lateritic minerals in favor of nickel extraction. The microbial mineral processing route offers many advantages over conventional metallurgical methods as the process is operated under ambient conditions and requires low energy input; thus these processes are relatively simple and environment friendly. Microbial processing of the lateritic deposits still needs improvement to make it industrially viable. Microorganisms play the pivotal role in mineral bio-processing as they catalyze the extraction of metals from minerals. So it is inevitable to explore the physiological and bio-molecular mechanisms involved in this microbe-mineral interaction. The present article offers comprehensive information about the advances in microbial processes for extraction of nickel from laterites.

  14. Direct observations of the atmospheric processing of Asian mineral dust

    Directory of Open Access Journals (Sweden)

    R. C. Sullivan

    2006-05-01

    Full Text Available The accumulation of secondary acid products and ammonium on individual mineral dust particles during ACE-Asia has been measured in real-time using ATOFMS. Changes in the amounts of sulphate, nitrate, and chloride mixed with dust particles corresponded to different air mass source regions. During volcanically influenced periods, dust mixed with sulphate dominated. This rapidly switched to dust predominantly mixed with chloride when the first Asian dust front reached the R/V Ronald Brown. We hypothesise that the high degree of mixing of dust with chloride was caused by the prior reaction of NOy(g and volcanic SO2(g with sea salt particles, reducing the availability of nitrate and sulphate precursors while releasing HCl(g, which then reacted with the incoming dust front. The segregation of sulphate from nitrate and chloride in individual dust particles is demonstrated for the first time. This is likely caused by the dust plume encountering elevated SO2(g in the Chinese interior before reaching coastal urban areas polluted by both SO2(g and NOx(g. This caused the fractions of dust mixed with nitrate and/or chloride to be strongly dependent on the total dust loadings, whereas dust mixed with sulphate did not show this same dust concentration dependence. Ammonium was also significantly mixed with dust and the amount correlated strongly with the total amount of secondary acid reaction products in the dust. Submicron dust and ammonium sulphate were internally mixed, contrary to frequent statements that they exist as an external mixture. The size distribution of the mixing state of dust with these secondary species validates previous models and mechanisms of the atmospheric processing of dust. The uptake of secondary acids was also dependent on the individual dust particle mineralogy; nitrate accumulated on calcium-rich dust while sulphate accumulated on aluminosilicate-rich dust. Oxidation of S

  15. A process for reducing rocks and concentrating heavy minerals

    Science.gov (United States)

    Strong, Thomas R.; Driscoll, Rhonda L.

    2016-03-30

    To obtain minerals suitable for age-dating and other analyses, it is necessary to first reduce the mineral-bearing rock to a fine, sand-like consistency. Reducing whole rock requires crushing, grinding, and sieving. Ideally, the reduced material should range in size from 80- to 270-mesh (an opening between wires in a sieve). The openings in an 80-mesh sieve are equal to 0.007 inches, 0.177 millimeters, or 177 micrometers. This size range ensures that compound grains are mostly disaggregated and that grains, in general, are dimensionally similar. This range also improves the segregation rate of conspicuous to extremely small individual heavy mineral grains.

  16. [Research on mineralization process of organic phosphorus in black soil in Northeast China].

    Science.gov (United States)

    Zhao, Shaohua; Yu, Wantai; Zhang, Lu; Shen, Shanmin

    2005-10-01

    Buried bag and incubation experiments were conducted to study mineralization process of organic phosphorus in black soil in Northeast China under different time sequences. The results showed that both the content and mineralized velocity of organic P decreased gradually as time went on, the cumulative mineralized rate increased step by step, whether it was used by the method of incubation or buried bag. Under incubation, two treatments' mineralized velocity reached the maximum at first month (31.67, 38.75 mg x kg(-1) x month(-1), respectively), and their cumulative mineralized rate and mineralized velocity at six months were 7.94%, 13.26 mg x kg(-1) x month(-1) and 9.24%, 17.99 mg x kg(-1) x month(-1), respectively. Under buried bag, the mineralized velocity of five treatments all reached the maximum at first year (55.67, 55.65, 49.60, 19.71, 22.52 mg x kg(-1) month(-1), respectively), and the cumulative mineralized rate and mineralized velocity of maize root and wheat root treatments at three years both were approximately 50% and 35 mg x kg(-1) x month(-1), which were higher than those under soybean root andgrass root treatments. From two methods of studies on the mineralization process of organic P, it could be seen that the original content of organic P influenced its mineralized rate and mineralized velocity: the higher of the original content of organic P, the higher of its mineralized rate and mineralized velocity.

  17. Multi-scale interactions of geological processes during mineralization: cascade dynamics model and multifractal simulation

    Directory of Open Access Journals (Sweden)

    L. Yao

    2011-03-01

    Full Text Available Relations between mineralization and certain geological processes are established mostly by geologist's knowledge of field observations. However, these relations are descriptive and a quantitative model of how certain geological processes strengthen or hinder mineralization is not clear, that is to say, the mechanism of the interactions between mineralization and the geological framework has not been thoroughly studied. The dynamics behind these interactions are key in the understanding of fractal or multifractal formations caused by mineralization, among which singularities arise due to anomalous concentration of metals in narrow space. From a statistical point of view, we think that cascade dynamics play an important role in mineralization and studying them can reveal the nature of the various interactions throughout the process. We have constructed a multiplicative cascade model to simulate these dynamics. The probabilities of mineral deposit occurrences are used to represent direct results of mineralization. Multifractal simulation of probabilities of mineral potential based on our model is exemplified by a case study dealing with hydrothermal gold deposits in southern Nova Scotia, Canada. The extent of the impacts of certain geological processes on gold mineralization is related to the scale of the cascade process, especially to the maximum cascade division number nmax. Our research helps to understand how the singularity occurs during mineralization, which remains unanswered up to now, and the simulation may provide a more accurate distribution of mineral deposit occurrences that can be used to improve the results of the weights of evidence model in mapping mineral potential.

  18. Bismuth mineral inclusions in gold-bearing magnetite from the giant Beiya gold deposit, SW China: insights into mineralization process

    Science.gov (United States)

    Zhou, Haoyang; Sun, Xiaoming

    2017-04-01

    Bismuth minerals are commonly found in a wide range of gold deposits and could offer valuable information on the process of gold mineralization. This is because Bi minerals always show immediate association with gold and are sensitive to chemical-physical variations (Afifi et al., 1988). Specifically, native bismuth has a melting point of 271°C and could melt at lower temperatures when gold is added (Okamoto et al,, 1983). It has been verified that Bi melt could efficiently scavenge gold from hydrothermal fluids (Tooth et al., 2008, 2011). The Beiya deposit, situated in the Sanjiang Tethyan tectonic domain in the southwestern China, is one of the largest gold deposits in China 10.4 Moz Au @ 2.47g/t). Located along the contacts between a 36 Ma quartz syenite porphyry and the Triassic limestones, the deposit contains abundant massive Au-bearing magnetite ores, which are considered as a product of skarn mineralization. However, the pivotal processes accounting for the huge accumulation of gold resource at Beiya area are poorly constrained. In the massive magnetite ores, abundant native gold was observed to be present as submicron-scale inclusions hosted by magnetite (Zhou et al., 2017). We also noted that abundant Bi minerals occur within these ores (Zhou et al., 2016), which provide critical clues to reveal the processes of gold mineralization. An assemblage of Bi minerals, composed of native bismuth, maldonite and bismuthinite, is present as tiny inclusions in these Au-bearing magnetite grains. Mineralogical study illustrates the encapsulation of native bismuth and maldonite as melts during magnetite growth, which is also supported by the ore-forming temperatures over 300°C derived from previous fluid inclusions study (He et al., 2016). Our thermodynamic modeling demonstrates that Bi melts scavenged gold from hydrothermal fluids. Subsequently, sulfidation of Bi melts resulted in precipitation of gold, which was captured by growing magnetite. We thus propose that

  19. Influence of processing on total and extractable mineral content of products prepared from potato flour.

    Science.gov (United States)

    Lakra, Poonam; Sehgal, Salil

    2011-12-01

    Potato (Solanum tuberosum) flour developed was used for preparing doughnuts, sevian, cutlet, kofta and vadi along with defatted soy (Glycine max) flour and corn (Zea mays) flour. Frying and fermentation were the major processing techniques employed for the development of these products. Significant differences in protein, ash and fat contents of all the products were observed due to their compositional differences. Processing did not affect on total mineral content. Processing increased (p mineral availability. Processed products had lower amount of anti nutrients as compared to raw counterparts and thus, higher mineral availability.

  20. The impact of food processing on the nutritional quality of vitamins and minerals.

    Science.gov (United States)

    Reddy, M B; Love, M

    1999-01-01

    Processing (including preparation) makes food healthier, safer, tastier and more shelf-stable. While the benefits are numerous, processing can also be detrimental, affecting the nutritional quality of foods. Blanching, for example, results in leaching losses of vitamins and minerals. Also, milling and extrusion can cause the physical removal of minerals during processing. The nutritional quality of minerals in food depends on their quantity as well as their bioavailability. The bioavailability of key minerals such as iron, zinc and calcium is known to be significantly affected by the fiber, phytic acid, and tannin content of foods. Concentrations of these constituents are altered by various processing methods including milling, fermentation, germination (sprouting), extrusion, and thermal processing. Vitamins, especially ascorbic acid, thiamin and folic acid, are highly sensitive to the same processing methods. The time and temperature of processing, product composition and storage are all factors that substantially impact the vitamin status of our foods.

  1. Differences in morphological properties between the olivine group minerals formed in natural and industrial processes

    Directory of Open Access Journals (Sweden)

    Dević S.

    2007-01-01

    Full Text Available Olivines are a large isomorphic series of minerals, belonging to silicates group. Regardless of their chemical composition, any of these minerals can be formed both in natural and industrial processes. The aim of this work is to describe these minerals and differences of morphological properties between the olivines formed in nature, and those formed as byproducts of some industrial processes , as Process Metalurgy-Ironmaking. The olivines whose formation is tied to rock masses (natural process and the olivines genetically tied to industrial processes of black metallurgy slags (process metallurgy-Ironmaking are shown in this paper. The morphological properties of these minerals and their differences have been analyzed by optical microscopy in refracted and in reflected light. .

  2. The Evaluation Of HGMS for Mineral Processing With a Single Wire

    OpenAIRE

    Watson, J. H. P.; Bahaj, A. S.; Rassi, D.

    1983-01-01

    In this short communication it is shown that it is possible to undertake inexpensive but useful preliminary mineral studies using single–wire HGMS. Such studies enable an assessment to be made of the viability of HGMS as a large-scale processing technique for particular mineral slurries.

  3. The Application of Microwave Energy in Mineral Processing – a Review

    Directory of Open Access Journals (Sweden)

    Michal Lovás

    2011-12-01

    Full Text Available This paper presents a review of the application of microwave energy in the field of mineral processing at the Institute of Geotechnics,Slovak Academy of Sciences. The influence of microwave radiation of rocks on the failure disintegration of minerals and ores as well as,a modification of magnetic properties and thermal processing of rocks was studied. Moreover, the rate of microwave heating of minerals,effect of microwaves on coal desulphurisation and the extraction of diterpanes from coal were investigated.

  4. [Analysis of changes in minerals contents during cider fermentation process by inductively coupled plasma mass spectrometry].

    Science.gov (United States)

    Ye, Meng-qi; Yue, Tian-li; Gao, Zhen-peng; Yuan, Ya-hong; Nie, Gang

    2015-01-01

    The changes in mineral elements during cider fermentation process were determined using ICP-MS. The results showed that the main minerals in the fermentation liquor included K, Na, Ca, Mg, Fe, Mn, Zn, Cu, Sr and B. The content of K was the highest in both the apple juice and the cider, being 1 853. 83 and 1 654. 38 mg . L-1 respectively. The content of minerals was in dynamic changes along with the fermentation process. As a whole, during 72-120 h and 144-216 h, most of the minerals contents underwent great fluctuation. Especially when fermented for 192 h, the content of most of the minerals reached peak value or valley value. The content of Fe and Zn achieved their peak value, while the content of K, Na, Ca, Mg, Mn and B achieved valley value. But during the following 24 h, the content of minerals underwent a sharp reversal. After fermentation, the content of K, Mg, Cu, Zn and B decreased significantly, while the content of Na, Ca, Mn, Fe and Sr did not change significantly. The correlational analysis was conducted to evaluate the correlation between the mineral elements, and the result showed that the correlation between Ca and Mn was the most significant, with the correlation index reaching 0. 924. The information of this study will supply sufficient data for the fermentation process control and quality improvement of cider.

  5. ATOMIC-LEVEL IMAGING OF CO2 DISPOSAL AS A CARBONATE MINERAL: OPTIMIZING REACTION PROCESS DESIGN

    Energy Technology Data Exchange (ETDEWEB)

    M.J. McKelvy; R. Sharma; A.V.G. Chizmeshya; H. Bearat; R.W. Carpenter

    2002-11-01

    Fossil fuels, especially coal, can support the energy demands of the world for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Permanent and safe methods for CO{sub 2} capture and disposal/storage need to be developed. Mineralization of stationary-source CO{sub 2} emissions as carbonates can provide such safe capture and long-term sequestration. Mg-rich lamellar-hydroxide based minerals (e.g., brucite and serpentine) offer a class of widely available, low-cost materials, with intriguing mineral carbonation potential. Carbonation of such materials inherently involves dehydroxylation, which can disrupt the material down to the atomic level. As such, controlled dehydroxylation, before and/or during carbonation, may provide an important parameter for enhancing carbonation reaction processes. Mg(OH){sub 2} was chosen as the model material for investigating lamellar hydroxide mineral dehydroxylation/carbonation mechanisms due to (1) its structural and chemical simplicity, (2) interest in Mg(OH){sub 2} gas-solid carbonation as a potentially cost-effective CO{sub 2} mineral sequestration process component, and (3) its structural and chemical similarity to other lamellar-hydroxide-based minerals (e.g., serpentine-based minerals) whose carbonation reaction processes are being explored due to their low-cost CO{sub 2} sequestration potential. Fundamental understanding of the mechanisms that govern dehydroxylation/carbonation processes is essential for minimizing the cost of any lamellar-hydroxide-based mineral carbonation sequestration process. This final report covers the overall progress of this grant.

  6. Mineral processing at Luleå University of Technology:meeting the research and educational needs

    OpenAIRE

    Rosenkranz, Jan

    2010-01-01

    With the start of the new decade the Mineral Processing chair at Luleå University of Technology has been newly appointed. The scientific redirection of the chair includes several of the important topic areas of advanced mineral processing. From process mineralogy via comminution and concentration processes to mathematical modelling and simulation of particulate processing systems, the mineral processing research at Luleå University of Technology is shaped by the interaction of material, proce...

  7. Surface modification of mineral dust particles by sulphuric acid processing: implications for ice nucleation abilities

    OpenAIRE

    P. Reitz; C. Spindler; T. F. Mentel; Poulain, L.; H. Wex; K. Mildenberger; D. Niedermeier; Hartmann, S.; T. Clauss; F. Stratmann; R. C. Sullivan; Demott, P. J.; Petters, M. D.; Sierau, B.; Schneider, J.

    2011-01-01

    The ability of coated mineral dust particles to act as ice nuclei (IN) was investigated at LACIS (Leipzig Aerosol Cloud Interaction Simulator) during the FROST1- and FROST2-campaigns (Freezing of dust). Sulphuric acid was condensed on the particles which afterwards were optionally humidified, treated with ammonia vapour and/or heat. By means of aerosol mass spectrometry we found evidence that processing of mineral dust particles with su...

  8. Fuzzy model of the computer integrated decision support and management system in mineral processing

    OpenAIRE

    Miljanović Igor; Vujić Slobodan

    2008-01-01

    During the research on the subject of computer integrated systems for decision making and management support in mineral processing based on fuzzy logic, realized at the Department of Applied Computing and System Engineering of the Faculty of Mining and Geology, University of Belgrade, for the needs of doctoral thesis of the first author, and wider demands of the mineral industry, the incompleteness of the developed and contemporary computer integrated systems fuzzy models was noticed. The pap...

  9. Atmospheric processing of iron carried by mineral dust

    Directory of Open Access Journals (Sweden)

    S. Nickovic

    2013-09-01

    Full Text Available Nutrification of the open ocean originates mainly from deposited aerosol in which the bio-avaliable iron is likely to be an important factor. The relatively insoluble iron in dust from arid soils becomes more soluble after atmospheric processing and, through its deposition in the ocean, could contribute to marine primary production. To numerically simulate the atmospheric route of iron from desert sources to sinks in the ocean, we developed a regional atmospheric dust-iron model that included parameterization of the transformation of iron to a soluble form caused by dust mineralogy, cloud processes and solar radiation. When compared with field data on the aerosol iron, which were collected during several Atlantic cruises, the results from the higher-resolution simulation experiments showed that the model was capable of reproducing the major observed patterns.

  10. Atmospheric processing of iron carried by mineral dust

    OpenAIRE

    S. Nickovic; A. Vukovic; M. Vujadinovic

    2013-01-01

    Nutrification of the open ocean originates mainly from deposited aerosol in which the bio-avaliable iron is likely to be an important factor. The relatively insoluble iron in dust from arid soils becomes more soluble after atmospheric processing and, through its deposition in the ocean, could contribute to marine primary production. To numerically simulate the atmospheric route of iron from desert sources to sinks in the ocean, we developed a regional atmospheric dust-iron model that included...

  11. Selected Geochemical Data for Modeling Near-Surface Processes in Mineral Systems

    Science.gov (United States)

    Giles, Stuart A.; Granitto, Matthew; Eppinger, Robert G.

    2009-01-01

    The database herein was initiated, designed, and populated to collect and integrate geochemical, geologic, and mineral deposit data in an organized manner to facilitate geoenvironmental mineral deposit modeling. The Microsoft Access database contains data on a variety of mineral deposit types that have variable environmental effects when exposed at the ground surface by mining or natural processes. The data tables describe quantitative and qualitative geochemical analyses determined by 134 analytical laboratory and field methods for over 11,000 heavy-mineral concentrate, rock, sediment, soil, vegetation, and water samples. The database also provides geographic information on geology, climate, ecoregion, and site contamination levels for over 3,000 field sites in North America.

  12. Evaluation of Mineral Deposits Along the Little Wind River, Riverton, WY, Processing Site

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Sam [Navarro Research and Engineering, Oak Ridge, TN (United States); Dam, Wiliam [US Department of Energy, Washington, DC (United States). Office of Legacy Management

    2014-12-01

    In 2012, the U.S.Department of Energy (DOE) began reassessing the former Riverton, Wyoming, Processing Site area for potential contaminant sources impacting groundwater. A flood in 2010 along the Little Wind River resulted in increases in groundwater contamination (DOE 2013).This investigation is a small part of continued efforts by DOE and other stakeholders to update human health and ecological risk assessments, to make a comprehensive examination of all exposure pathways to ensure that the site remains protective through established institutional controls. During field inspections at the Riverton Site in 2013, a white evaporitic mineral deposit was identified along the bank of the Little Wind River within the discharge zone of the groundwater contamination plume. In December 2013, Savannah River National Laboratory (SRNL) personnel collected a sample for analysis by X-ray fluorescence (Figure 1 shows the type of material sampled). The sample had a uranium concentration of approximately 64 to 73 parts per million. Although the uranium in this mineral deposit is within the expected range for evaporatic minerals in the western United States (SRNL 2014), DOE determined that additional assessment of the mineral deposit was warranted. In response to the initial collection and analysis of a sample of the mineral deposit, DOE developed a work plan (Work Plan to Sample Mineral Deposits Along the Little Wind River, Riverton, Wyoming, Processing Site [DOE 2014]) to further define the extent of these mineral deposits and the concentration of the associated contaminants (Appendix A). The work plan addressed field reconnaissance, mapping, sampling, and the assessment of risk associated with the mineral deposits adjacent to the Little Wind River.

  13. Atmospheric processing outside clouds increases soluble iron in mineral dust.

    Science.gov (United States)

    Shi, Zongbo; Krom, Michael D; Bonneville, Steeve; Benning, Liane G

    2015-02-03

    Iron (Fe) is a key micronutrient regulating primary productivity in many parts of the global ocean. Dust deposition is an important source of Fe to the surface ocean, but most of this Fe is biologically unavailable. Atmospheric processing and reworking of Fe in dust aerosol can increase the bioavailable Fe inputs to the ocean, yet the processes are not well understood. Here, we experimentally simulate and model the cycling of Fe-bearing dust between wet aerosol and cloud droplets. Our results show that insoluble Fe in dust particles readily dissolves under acidic conditions relevant to wet aerosols. By contrast, under the higher pH conditions generally relevant to clouds, Fe dissolution tends to stop, and dissolved Fe precipitates as poorly crystalline nanoparticles. If the dust-bearing cloud droplets evaporated again (returning to the wet aerosol stage with low pH), those neo-formed Fe nanoparticles quickly redissolve, while the refractory Fe-bearing phases continue to dissolve gradually. Overall, the duration of the acidic, wet aerosol stage ultimately increases the amount of potentially bioavailable Fe delivered to oceans, while conditions in clouds favor the formation of Fe-rich nanoparticles in the atmosphere.

  14. Exposure of workers in a mineral processing industry in Brazil.

    Science.gov (United States)

    Julião, Lígia M Q C; Melo, Dunstana R; Sousa, Wanderson O; Santos, Maristela S; Fernandes, Paulo César; Godoy, Maria Luiza D P

    2007-01-01

    In Brazil there are many regions where the extraction mining and processing of ores containing elements of great economical importance as tin, niobium and tantalum. Some of these ores have uranium and thorium natural decay series associated. This study was carried out in a niobium mine, where is obtained concentrates of niobates-tantalates, cassiterite and zirconite. The aim of this study is the evaluation of the occupational exposure to uranium, thorium, niobium and tin through urine bioassay data. In order to have it, 105 urine samples were analysed: 17 samples of exposed workers collected after a working day, 49 samples of exposed workers collected before a working day and 39 samples of local non-exposed people, assigned as a control group. The samples were analysed by mass spectrometry. The obtained results showed that the average concentration of Nb, Sn and U in the exposed group is statistically higher than those found in the control group indicating an occupational exposure. For Th there were no statistically difference between the exposed and the control group.

  15. Microbial mineralization of struvite: a promising process to overcome phosphate sequestering crisis.

    Science.gov (United States)

    Sinha, Arvind; Singh, Amit; Kumar, Sumit; Khare, Sunil Kumar; Ramanan, Arunachalam

    2014-05-01

    Due to extensive exploitation of non-renewable phosphate minerals, their natural reserves will exhaust very soon. This necessitates looking for alternatives and an efficient methodology through which indispensable phosphorus can be harvested back. The current study was undertaken to explore the potential of a metallophilic bacterium Enterobacter sp. EMB19 for the recovery of phosphorus as phosphate rich mineral. A very low phosphate concentration strategy was adopted. The process led to the mineralization of phosphorus as homogeneous struvite crystals. For each gram of Epsom salt added, the cells effectively mineralized about 20% of the salt into struvite. The effect of different inorganic sources, culture profile and plausible mechanism involved in crystal formation was also explored. The synthesized struvite crystals typically possessed a prismatic crystal habit. The characterization and identification of the crystals were done using single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), energy dispersive X-ray analysis (EDAX) and fourier transform infrared (FTIR). The thermal characteristics were studied using thermo gravimetric analysis (TGA) and differential scanning calorimetric (DSC) processes. The synthesis of struvite by this bacterium seems to be a promising and viable strategy since it serves dual purpose (i) obtaining phosphorus and nitrogen rich fertilizer and (ii) conservation of natural phosphate reserves. This study is very significant in the sense that the process may be used for harvesting and synthesizing other valuable minerals. Also, it will provide new insights into phosphate biomineralization mechanisms.

  16. Influence of preferred orientation of minerals in the mineralogical identification process by X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Amanda Luzia da; Oliveira, Arno H. de [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear; Fernandes, Maria Lourdes Souza, E-mail: lourdesfernandes@ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Inst. de GeoCiencias. Centro de Pesquisa Professor Manoel Teixeira da Costa

    2011-07-01

    The X-ray diffraction corresponds to one of the main techniques for characterization of microstructures in crystalline materials, widely used in the identification of minerals in samples of geological materials. Some minerals have a property called preferred orientation which corresponds to the orientation tendency of the crystals of ground minerals to orient themselves in certain directions according to a preferred crystallographic plane. This property affects the analysis by X-ray diffraction and this fact can generates erroneous results in the characterization. The purpose of this study is to identify the negative influence of the preferred orientation of a mineral in the generation of diffraction patterns obtained in the X-ray diffraction analysis. For this, a sample of muscovite, a mineral of mica group, was prepared by two different methods: the frontal method and the back loading method. In the analysis using the frontal method there was displacement of the XRD pattern in the abscissa axis, where it was observed changes in interplanar distance and angle 2{theta} values, which are essential information for characterization and identification of a mineral. In the analysis using the back loading method, the generated XRD pattern showed no displacement in the axis of abscissas and showed interplanar distance and angle 2{theta} values closer to the real values for the muscovite. The results showed that one can only make improvements to the process of sample preparation minimizing the effect of preferred orientation in the analysis. There is no need to change conditions of diffractometer measurements. (author)

  17. Predicting the Mineral Composition of Dust Aerosols. Part 1; Representing Key Processes

    Science.gov (United States)

    Perlwitz, J. P.; Garcia-Pando, C. Perez; Miller, R. L.

    2015-01-01

    Soil dust aerosols created by wind erosion are typically assigned globally uniform physical and chemical properties within Earth system models, despite known regional variations in the mineral content of the parent soil. Mineral composition of the aerosol particles is important to their interaction with climate, including shortwave absorption and radiative forcing, nucleation of cloud droplets and ice crystals, heterogeneous formation of sulfates and nitrates, and atmospheric processing of iron into bioavailable forms that increase the productivity of marine phytoplankton. Here, aerosol mineral composition is derived by extending a method that provides the composition of a wet-sieved soil. The extension accounts for measurements showing significant differences between the mineral fractions of the wetsieved soil and the emitted aerosol concentration. For example, some phyllosilicate aerosols are more prevalent at silt sizes, even though they are nearly absent at these diameters in a soil whose aggregates are dispersed by wet sieving. We calculate the emitted mass of each mineral with respect to size by accounting for the disintegration of soil aggregates during wet sieving. These aggregates are emitted during mobilization and fragmentation of the original undispersed soil that is subject to wind erosion. The emitted aggregates are carried far downwind from their parent soil. The soil mineral fractions used to calculate the aggregates also include larger particles that are suspended only in the vicinity of the source. We calculate the emitted size distribution of these particles using a normalized distribution derived from aerosol measurements. In addition, a method is proposed for mixing minerals with small impurities composed of iron oxides. These mixtures are important for transporting iron far from the dust source, because pure iron oxides are more dense and vulnerable to gravitational removal than most minerals comprising dust aerosols. A limited comparison to

  18. Mineralization of 2-chlorophenol by sequential electrochemical reductive dechlorination and biological processes

    Energy Technology Data Exchange (ETDEWEB)

    Arellano-González, Miguel Ángel; González, Ignacio [Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Química, Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico D.F. (Mexico); Texier, Anne-Claire, E-mail: actx@xanum.uam.mx [Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Biotecnología, Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico, D.F. (Mexico)

    2016-08-15

    Highlights: • Dechlorination of 2-chlorophenol to phenol was 100% efficient on Pd-Ni/Ti electrode. • An ECCOCEL reactor was efficient and selective to obtain phenol from 2-chlorophenol. • Phenol was totally mineralized in a coupled denitrifying biorreactor. • Global time of 2-chlorophenol mineralization in the combined system was 7.5 h. - Abstract: In this work, a novel approach was applied to obtain the mineralization of 2-chlorophenol (2-CP) in an electrochemical-biological combined system where an electrocatalytic dehydrogenation process (reductive dechlorination) was coupled to a biological denitrification process. Reductive dechlorination of 2-CP was conducted in an ECCOCEL-type reactor on a Pd-Ni/Ti electrode at a potential of −0.40 V vs Ag/AgCl{sub (s)}/KCl{sub (sat)}, achieving 100 percent transformation of 2-CP into phenol. The electrochemically pretreated effluent was fed to a rotating cylinder denitrifying bioreactor where the totality of phenol was mineralized by denitrification, obtaining CO{sub 2} and N{sub 2} as the end products. The total time required for 2-CP mineralization in the combined electrochemical-biological process was 7.5 h. This value is close to those previously reported for electrochemical and advanced oxidation processes but in this case, an efficient process was obtained without accumulation of by-products or generation of excessive energy costs due to the selective electrochemical pretreatment. This study showed that the use of electrochemical reductive pretreatment combined with biological processes could be a promising technology for the removal of recalcitrant molecules, such as chlorophenols, from wastewaters by more efficient, rapid, and environmentally friendly processes.

  19. Development of a Dynamic Population Balance Plant Simulator for Mineral Processing Circuits

    Directory of Open Access Journals (Sweden)

    Fatemeh Khoshnam

    2015-06-01

    Full Text Available Operational variables of a mineral processing circuit are subjected to different variations. Steady-statesimulation of processes provides an estimate of their ideal stable performance whereas their dynamicsimulation predicts the effects of the variations on the processes or their subsequent processes. In thispaper, a dynamic simulator containing some of the major equipment of mineral processing circuits(i.e. ball mill, cone crusher, screen, hydrocyclone, mechanical flotation cell, tank leaching andconveyor belt was developed. The dynamic simulator of each mentioned unit was also developedaccording to population balance models with the help of MATLAB/Simulink environment and wasverified against the data from the literature. Comminution and separation sections were linked usingempirical models which correlate the separation and extraction kinetics to particle size. Applying thedeveloped simulator, the dynamic behavior of a grinding-leaching circuit was analyzed and the resultsshowed that such simulations are required for both designing and controlling the circuits.

  20. EFFECT OF LIQUID TO SOLID RATIO ON LEACHING OF METALS FROM MINERAL PROCESSING WASTE

    Science.gov (United States)

    Various anthropogenic activities generate hazardous solid wastes that are affluent in heavy metals, which can cause significant damage to the environment an human health. A mineral processing waste was used to study the effect of liquid to solid ratio (L/S) on the leaching behav...

  1. Leaching Behavior Of Mineral Processing Waste: Comparison Of Batch And Column Investigations

    Science.gov (United States)

    In this study, a comparison of laboratory batch and column experiments on metal release profile from a mineral processing waste (MPW) is presented. Batch (equilibrium) and column (dynamic) leaching tests were conducted on ground MPW at different liquid–solid ratios (LS) to determ...

  2. ARSENIC LEACHING FROM IRON RICH MINERAL PROCESSING WASTE: INFLUENCE OF PH AND REDOX POTENTIAL

    Science.gov (United States)

    This paper presents the effect of pH and redox potential on the potential mobility of arsenic (As) from a contaminated mineral processing waste. The selected waste contained about 0.47 g kg-1 of As and 66.2 g kg-1 of iron (Fe). The characteristic of the wast...

  3. Carbon dioxide mineralization process design and evaluation: concepts, case studies, and considerations.

    Science.gov (United States)

    Yuen, Yeo Tze; Sharratt, Paul N; Jie, Bu

    2016-11-01

    Numerous carbon dioxide mineralization (CM) processes have been proposed to overcome the slow rate of natural weathering of silicate minerals. Ten of these proposals are mentioned in this article. The proposals are described in terms of the four major areas relating to CM process design: pre-treatment, purification, carbonation, and reagent recycling operations. Any known specifics based on probable or representative operating and reaction conditions are listed, and basic analysis of the strengths and shortcomings associated with the individual process designs are given in this article. The processes typically employ physical or chemical pseudo-catalytic methods to enhance the rate of carbon dioxide mineralization; however, both methods have its own associated advantages and problems. To examine the feasibility of a CM process, three key aspects should be included in the evaluation criteria: energy use, operational considerations as well as product value and economics. Recommendations regarding the optimal level of emphasis and implementation of measures to control these aspects are given, and these will depend very much on the desired process objectives. Ultimately, a mix-and-match approach to process design might be required to provide viable and economic proposals for CM processes.

  4. Fuzzy model of the computer integrated decision support and management system in mineral processing

    Directory of Open Access Journals (Sweden)

    Miljanović Igor

    2008-01-01

    Full Text Available During the research on the subject of computer integrated systems for decision making and management support in mineral processing based on fuzzy logic, realized at the Department of Applied Computing and System Engineering of the Faculty of Mining and Geology, University of Belgrade, for the needs of doctoral thesis of the first author, and wider demands of the mineral industry, the incompleteness of the developed and contemporary computer integrated systems fuzzy models was noticed. The paper presents an original model with the seven staged hierarchical monitoring-management structure, in which the shortcomings of the models utilized today were eliminated.

  5. Predicting the mineral composition of dust aerosols – Part 1: Representing key processes

    Directory of Open Access Journals (Sweden)

    J. P. Perlwitz

    2015-02-01

    Full Text Available Soil dust aerosols created by wind erosion are typically assigned globally uniform physical and chemical properties within Earth system models, despite known regional variations in the mineral content of the parent soil. Mineral composition of the aerosol particles is important to their interaction with climate, including shortwave absorption and radiative forcing, nucleation of cloud droplets and ice crystals, coating by heterogeneous uptake of sulfates and nitrates, and atmospheric processing of iron into bioavailable forms that increase the productivity of marine phytoplankton. Here, aerosol mineral composition is derived by extending a method that provides the composition of a wet-sieved soil. The extension accounts for measurements showing significant differences between the mineral fractions of the wet-sieved soil and the resulting aerosol concentration. For example, some phyllosilicate aerosols are more prevalent at silt sizes, even though they are nearly absent in a soil whose aggregates are dispersed by wet sieving during analysis. We reconstruct the undispersed size distribution of the original soil that is subject to wind erosion. An empirical constraint upon the relative emission of clay and silt is applied that further differentiates the soil and aerosol mineral composition. In addition, a method is proposed for mixing minerals with small impurities composed of iron oxides. These mixtures are important for transporting iron far from the dust source, because pure iron oxides are more dense and vulnerable to gravitational removal than most minerals comprising dust aerosols. A limited comparison to measurements from North Africa shows that the extension brings the model into better agreement, consistent with a more extensive comparison to global observations as well as measurements of elemental composition downwind of the Sahara, as described in companion articles.

  6. Mineralization of 2-chlorophenol by sequential electrochemical reductive dechlorination and biological processes.

    Science.gov (United States)

    Arellano-González, Miguel Ángel; González, Ignacio; Texier, Anne-Claire

    2016-08-15

    In this work, a novel approach was applied to obtain the mineralization of 2-chlorophenol (2-CP) in an electrochemical-biological combined system where an electrocatalytic dehydrogenation process (reductive dechlorination) was coupled to a biological denitrification process. Reductive dechlorination of 2-CP was conducted in an ECCOCEL-type reactor on a Pd-Ni/Ti electrode at a potential of -0.40V vs Ag/AgCl(s)/KCl(sat), achieving 100 percent transformation of 2-CP into phenol. The electrochemically pretreated effluent was fed to a rotating cylinder denitrifying bioreactor where the totality of phenol was mineralized by denitrification, obtaining CO2 and N2 as the end products. The total time required for 2-CP mineralization in the combined electrochemical-biological process was 7.5h. This value is close to those previously reported for electrochemical and advanced oxidation processes but in this case, an efficient process was obtained without accumulation of by-products or generation of excessive energy costs due to the selective electrochemical pretreatment. This study showed that the use of electrochemical reductive pretreatment combined with biological processes could be a promising technology for the removal of recalcitrant molecules, such as chlorophenols, from wastewaters by more efficient, rapid, and environmentally friendly processes.

  7. Raman signal processing software for automated identification of mineral phases and biosignatures on Mars.

    Science.gov (United States)

    Sobron, Pablo; Sobron, Francisco; Sanz, Aurelio; Rull, Fernando

    2008-04-01

    Data from the ESA ExoMars Rover Mission will provide invaluable input for further studies in astro/exobiology. The search for mineral products as indicators of present and/or past biogenetic activities in Mars' surface and subsurface samples is the main objective of the compact Raman-laser-induced breakdown spectroscopy (LIBS) instrument. The inherent features of Raman spectroscopy and LIBS make the combined instrument a unique and very powerful tool in the search for biomarkers and hence it is regarded as the highest priority instrument for mineral analysis within the mission. We have developed a software package for the on-board processing of the instrument's data outputs, including spectral conditioning and search-match characterization of mineral phases and biomarkers. In this paper we show the mathematical and physical basis of the software package.

  8. Interface-coupled dissolution-precipitation processes during acidic weathering of multicomponent minerals

    Science.gov (United States)

    Ruiz-Agudo, Encarnacion; King, Helen E.; Patiño-López, Luis D.; Putnis, Christine V.; Geisler, Thorsten; Rodriguez-Navarro, Carlos M.; Putnis, Andrew

    2015-04-01

    The chemical weathering of carbonate and silicate minerals on the Earth's surface controls important geochemical processes such as erosion rates and soil formation, ore genesis or climate evolution. The dissolution of most of these minerals is typically incongruent, and results in the formation of surface coatings (altered layers, also known as leached layers). These coatings may significantly affect mineral dissolution rates over geological timescales, and therefore a great deal of research has been conducted on them. However, the mechanism of leached layer formation is a matter of vigorous debate. Here we report on an in situ atomic force microscopy (AFM) and real-time Mach-Zehnder phase-shift interferometry (PSI) study of the dissolution of wollastonite, CaSiO3, and dolomite, CaMg(CO3)2, as an example of surface coating formation during acidic weathering of multicomponent minerals. Our in situ results provide clear direct experimental evidence that leached layers are formed in a tight interface-coupled two-step process: stoichiometric dissolution of the pristine mineral surfaces and subsequent precipitation of a secondary phase (silica in the case of wollastonite, or hydrated magnesium carbonate in the case of dolomite) from a supersaturated boundary layer of fluid in contact with the mineral surface. This occurs despite the bulk solution remaining undersaturated with respect to the secondary phase. The validation of such a mechanism given by the results reported here completely changes the conceptual framework concerning the mechanism of chemical weathering, and differs significantly from the concept of preferential leaching of cations postulated by most currently accepted incongruent dissolution models.

  9. Mesoscale Phenomena Associated with Mineral Surfaces and Pathway-Dependent Chemical Processes

    Science.gov (United States)

    Brown, G. E.; Johnson, N. C.; Garcia Del Real, P.; Maher, K.; Bird, D. K.; Rosenbauer, R. J.; Thomas, B.; Levard, C.

    2012-12-01

    Multiphase physicochemical transport and interfacial processes in natural and synthetic permeable media are pervasive in energy and Earth systems, where interfacial chemical reactions play an enormous role. These coupled reactions control the composition of our environment, including the atmosphere, oceans, and groundwaters, and the soils derived from interactions of atmospheric gases and natural waters with solid phases. Aqueous fluids, liquid hydrocarbons, and gases flow through permeable geological media along pathways that can be exceedingly complex at the nano- to microscales. Adding to this complexity are the chemical reactions occurring along these pathways that can irreversibly alter permeability and porosity as well as the compositions of fluid, gas, and solid phases, depending on physicochemical conditions. This talk will discuss the role of chemical reactions on mineral surfaces in several areas, including the structure of the electrical double layer at mineral/water interfaces and how it changes as a function of solution conditions, sequestration and transformation of environmental contaminants on mineral surfaces, mineral carbonation reactions and CO2 sequestration, and nanoparticle stability and transformations in natural systems. It will also include examples of pathway-dependent mesoscale chemical processes in the synthetic world involving energy materials. Examples in this area will include a synchrotron-based high-resolution 3D tomography study of Li-NiO battery electrodes under in operando conditions and metal-organic framework structures that can be used for hydrogen storage, separation, catalysis, and sequestration.

  10. Application of Ozone Related Processes to Mineralize Tetramethyl Ammonium Hydroxide in Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Chyow-San Chiou

    2013-01-01

    Full Text Available Tetramethyl ammonium hydroxide (TMAH is an anisotropic etchant used in the wet etching process of the semiconductor industry and is hard to degrade by biotreatments when it exists in wastewater. This study evaluated the performance of a system combined with ultraviolet, magnetic catalyst (SiO2/Fe3O4 and O3, denoted as UV/O3, to TMAH in an aqueous solution. The mineralization efficiency of TMAH under various conditions follows the sequence: UV/O3 > UV/H2O2/O3 > H2O2/SiO2/Fe3O4/O3 > H2O2/O3 > SiO2/Fe3O4/O3 > O3 > UV/H2O2. The results suggest that UV/O3 process provides the best condition for the mineralization of TMAH (40 mg/L, resulting in 87.6% mineralization, at 60 min reaction time. Furthermore, the mineralization efficiency of SiO2/Fe3O4/H2O2/O3 was significantly higher than that of O3, H2O2/O3, and UV/H2O2. More than 90% of the magnetic catalyst was recovered and easily redispersed in a solution for reuse.

  11. Tracking the Mind's Eye: A New Technology for Researching Twenty-First-Century Writing and Reading Processes

    Science.gov (United States)

    Anson, Chris M.; Schwegler, Robert A.

    2012-01-01

    This article describes the nature of eye-tracking technology and its use in the study of discourse processes, particularly reading. It then suggests several areas of research in composition studies, especially at the intersection of writing, reading, and digital media, that can benefit from the use of this technology. (Contains 2 figures.)

  12. Improved process control through real-time measurement of mineral content

    Energy Technology Data Exchange (ETDEWEB)

    Turler, Daniel; Karaca, Murat; Davis, William B.; Giauque, Robert D.; Hopkins, Deborah

    2001-11-02

    In a highly collaborative research and development project with mining and university partners, sensors and data-analysis tools are being developed for rock-mass characterization and real-time measurement of mineral content. Determining mineralogy prior to mucking in an open-pit mine is important for routing the material to the appropriate processing stream. A possible alternative to lab assay of dust and cuttings obtained from drill holes is continuous on-line sampling and real-time x-ray fluorescence (XRF) spectroscopy. Results presented demonstrate that statistical analyses combined with XRF data can be employed to identify minerals and, possibly, different rock types. The objective is to create a detailed three-dimensional mineralogical map in real time that would improve downstream process efficiency.

  13. Decolorization and mineralization of Allura Red AC aqueous solutions by electrochemical advanced oxidation processes

    Energy Technology Data Exchange (ETDEWEB)

    Thiam, Abdoulaye; Sirés, Ignasi; Garrido, José A.; Rodríguez, Rosa M.; Brillas, Enric, E-mail: brillas@ub.edu

    2015-06-15

    Highlights: • Quicker degradation of Allura Red AC in the order EO-H{sub 2}O{sub 2} < EF < PEF with Pt or BDD anode. • Almost total mineralization achieved by the most powerful PEF process with BDD. • Similar decolorization and mineralization rate in SO{sub 4}{sup 2−}, ClO{sub 4}{sup −} and NO{sub 3}{sup −} media. • In Cl{sup −} medium, only slightly larger decolorization rate but strong inhibition of mineralization. • Identification of aromatic products, carboxylic acids and released NH{sub 4}{sup +}, NO{sub 3}{sup −} and SO{sub 4}{sup 2−} ions. - Abstract: The decolorization and mineralization of solutions containing 230 mg L{sup −1} of the food azo dye Allura Red AC at pH 3.0 have been studied upon treatment by electrochemical oxidation with electrogenerated H{sub 2}O{sub 2} (EO-H{sub 2}O{sub 2}), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed with a stirred tank reactor containing a boron-doped diamond (BDD) or Pt anode and an air-diffusion cathode to generate H{sub 2}O{sub 2}. The main oxidants were hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton’s reaction between H{sub 2}O{sub 2} and added Fe{sup 2+}. The oxidation ability increased in the sequence EO-H{sub 2}O{sub 2} < EF < PEF and faster degradation was always obtained using BDD. PEF process with BDD yielded almost total mineralization following similar trends in SO{sub 4}{sup 2−}, ClO{sub 4}{sup −} and NO{sub 3}{sup −} media, whereas in Cl{sup −} medium, mineralization was inhibited by the formation of recalcitrant chloroderivatives. GC–MS analysis confirmed the cleavage of the −N=N− bond with formation of two main aromatics in SO{sub 4}{sup 2−} medium and three chloroaromatics in Cl{sup −} solutions. The effective oxidation of final oxalic and oxamic acids by BDD along with the photolysis of Fe(III)-oxalate species by UVA light accounted for the superiority of PEF with BDD. NH{sub 4

  14. Electrochemical mineralization of the antibiotic levofloxacin by electro-Fenton-pyrite process.

    Science.gov (United States)

    Barhoumi, Natija; Labiadh, Lazhar; Oturan, Mehmet A; Oturan, Nihal; Gadri, Abdellatif; Ammar, Salah; Brillas, Enric

    2015-12-01

    Levofloxacin is a large spectrum antibiotic from fluoroquinolones family, widely used and detected in natural waters. Here, this drug was degraded by a novel heterogeneous electro-Fenton (EF) process, so-called EF-pyrite, in which pyrite powder in suspension regulates the solution pH to 3.0 and supplies 0.2mM Fe(2+) as catalyst to the solution. Trials were performed with a stirred boron-doped diamond (BDD)/carbon-felt cell under O2 bubbling for cathodic H2O2 generation. Hydroxyl radicals formed from water oxidation at the BDD anode and in the bulk from Fenton's reaction between Fe(2+) and H2O2 were the main oxidizing agents. The effect of applied current and antibiotic concentration over the mineralization rate and degree, mineralization current efficiency and specific energy consumption was studied. An almost total mineralization was achieved for a 0.23mM drug solution operating at 300mA for 8h. The kinetic decay of the drug was followed by reversed-phase HPLC and obeyed a pseudo-first-order reaction. Ion-exclusion HPLC analysis of treated solutions revealed that oxalic and oxamic acids, the most persistent final products, were the predominant pollutants remaining in solution at long electrolysis time. Ion chromatography analysis confirmed the release of F(-), NO3(-) and NH4(+) ions during levofloxacin mineralization. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Decolorization and mineralization of Allura Red AC aqueous solutions by electrochemical advanced oxidation processes.

    Science.gov (United States)

    Thiam, Abdoulaye; Sirés, Ignasi; Garrido, José A; Rodríguez, Rosa M; Brillas, Enric

    2015-06-15

    The decolorization and mineralization of solutions containing 230 mg L(-1) of the food azo dye Allura Red AC at pH 3.0 have been studied upon treatment by electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed with a stirred tank reactor containing a boron-doped diamond (BDD) or Pt anode and an air-diffusion cathode to generate H2O2. The main oxidants were hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between H2O2 and added Fe(2+). The oxidation ability increased in the sequence EO-H2O2 process with BDD yielded almost total mineralization following similar trends in SO4(2-), ClO4(-) and NO3(-) media, whereas in Cl(-) medium, mineralization was inhibited by the formation of recalcitrant chloroderivatives. GC-MS analysis confirmed the cleavage of the −N=N− bond with formation of two main aromatics in SO4(2-) medium and three chloroaromatics in Cl(-) solutions. The effective oxidation of final oxalic and oxamic acids by BDD along with the photolysis of Fe(III)-oxalate species by UVA light accounted for the superiority of PEF with BDD. NH4(+), NO3(-) and SO4(2-) ions were released during the mineralization.

  16. Phosphates (V) recovery from phosphorus mineral fertilizers industry wastewater by continuous struvite reaction crystallization process.

    Science.gov (United States)

    Hutnik, Nina; Kozik, Anna; Mazienczuk, Agata; Piotrowski, Krzysztof; Wierzbowska, Boguslawa; Matynia, Andrzej

    2013-07-01

    Continuous DT MSMPR (Draft Tube Mixed Suspension Mixed Product Removal) crystallizer was provided with typical wastewater from phosphorus mineral fertilizers industry (pH phosphate(V) ions decreased from 0.445 to 9.2 × 10(-4) mass %. This can be regarded as a very good process result. In product crystals, besides main component - struvite, all impurities from wastewater were detected analytically.

  17. Fabrication of Bio-Nanocomposite Nanofibers Mimicking the Mineralized Hard Tissues via Electrospinning Process

    OpenAIRE

    2010-01-01

    In the present work we demonstrate a powerful technique for fabricating biocompatible and biodegradable PVA/HAp nanocomposite fibers in order to mimic mineralized hard tissues for bone regeneration purpose by applying the electro spinning process. Various techniques, including TEM, HR-TEM, SEM, XRD, DSC, TGA, FTIR spectroscopy were performed to characterize the resulting electrospun PVA/HAp composite nanofibers in comparison with pure PVA and PVA/HAp nanocomposites before electrospinning. Mor...

  18. Hydrochemical features and mineralization processes in coastal groundwater of Oualidia, Morocco

    Science.gov (United States)

    Fadili, Ahmed; Najib, Saliha; Mehdi, Khalid; Riss, Joëlle; Makan, Abdelhadi; Boutayeb, Khadija; Guessir, Hakima

    2016-04-01

    The objective of this study is to identify the influence of different hydrochemical processes, potential salinity sources, and seawater intrusion on groundwater quality in the coastal region of Oualidia. For this purpose, chemical analyses were performed on 19 wells sampled during three campaigns: June and December, 2010 and May, 2011. Investigations were conducted to identify the significant chemical variations between different campaigns. In addition, chemical variations were controlled by two main factors, which are the distance from the coast and the morphological aspect. Furthermore, statistical analysis allows the identification of two clusters of samples. The first groups, near the ocean, are highly mineralized with dominance of Na+ and Cl- ions, while the second group, much farther from the coast, are slightly mineralized with dominance of Ca2+ and HCO3- ions. Besides, ionic ratio, ionic delta, saturation index, and Gibbs diagram were applied to evaluate geochemical processes responsible for groundwater mineralization. Results showed that salinity was due mainly to seawater intrusion, especially in the first kilometers from the ocean covering the first group of wells. Moreover, cation exchange between Na+, Ca2+, Mg2+, and K+, evaporation, and evaporate dissolution are principal processes, which also contribute to groundwater salinization. In overall, this investigation provided a basis of geochemical data to effectively manage groundwater resource and efficiently mitigate impacts on aquifers.

  19. Environmental consequences of processing manure to produce mineral fertilizer and bio-energy.

    Science.gov (United States)

    De Vries, J W; Groenestein, C M; De Boer, I J M

    2012-07-15

    Liquid animal manure and its management contributes to environmental problems such as, global warming, acidification, and eutrophication. To address these environmental issues and their related costs manure processing technologies were developed. The objective here was to assess the environmental consequences of a new manure processing technology that separates manure into a solid and liquid fraction and de-waters the liquid fraction by means of reverse osmosis. This results in a liquid mineral concentrate used as mineral nitrogen and potassium fertilizer and a solid fraction used for bio-energy production or as phosphorus fertilizer. Five environmental impact categories were quantified using life cycle assessment: climate change (CC), terrestrial acidification (TA), marine eutrophication (ME), particulate matter formation (PMF), and fossil fuel depletion (FFD). For pig as well as dairy cattle manure, we compared a scenario with the processing method and a scenario with additional anaerobic digestion of the solid fraction to a reference situation applying only liquid manure. Comparisons were based on a functional unit of 1 ton liquid manure. System boundaries were set from the manure storage under the animal house to the field application of all end products. Scenarios with only manure processing increased the environmental impact for most impact categories compared to the reference: ME did not change, whereas, TA and PMF increased up to 44% as a result of NH3 and NO(x) emissions from processing and storage of solid fraction. Including digestion reduced CC by 117% for pig manure and 104% for dairy cattle manure, mainly because of substituted electricity and avoided N2O emission from storage of solid fraction. FFD decreased by 59% for pig manure and increased 19% for dairy cattle manure. TA and PMF remained higher compared to the reference. Sensitivity analysis showed that CH4 emission from manure storage, NH3 emission from processing, and the replaced nitrogen

  20. Taking another look with fluorescence microscopy: image processing techniques in Langmuir monolayers for the twenty-first century.

    Science.gov (United States)

    Stottrup, Benjamin L; Nguyen, Andrew H; Tüzel, Erkan

    2010-07-01

    Fluorescence microscopy has become a powerful and standard complementary technique in the study of amphiphilic films at the air-water interface. For nearly three decades the coupling of traditional thermodynamic measurements with direct visualization has provided a better understanding of self-assembled Langmuir monolayers and their application in the study of the physical properties of membranes and interfaces. As an introduction we provide a brief overview of this established technique and demonstrate its continued utility in the recent observation of novel phase behavior in monolayers of 25-hydroxycholesterol (25-OH) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). We then focus our review on new analysis techniques which take advantage of the ability to store, process, and analyze large sets of images. We pay particular attention to efforts measuring the line tension between coexisting two dimensional fluid phases in the Langmuir monolayer. Using non-perturbative methods, we can measure fundamental mechanical properties of these two dimensional systems. Finally, we highlight the use of Model Convolution Microscopy as a new tool to provide insight on the experimental limits in these studies. Copyright 2009 Elsevier B.V. All rights reserved.

  1. Mineral oils

    Science.gov (United States)

    Furby, N. W.

    1973-01-01

    The characteristics of lubricants made from mineral oils are discussed. Types and compositions of base stocks are reviewed and the product demands and compositions of typical products are outlined. Processes for commercial production of mineral oils are examined. Tables of data are included to show examples of product types and requirements. A chemical analysis of three types of mineral oils is reported.

  2. Optimizing Location of Bulk Metallic Minerals Processing Based on Greenhouse Gas Avoidance

    Directory of Open Access Journals (Sweden)

    Benjamin C. McLellan

    2011-12-01

    Full Text Available The bulk minerals iron ore and bauxite cause significant greenhouse emissions in their processing to steel and aluminum respectively. The level of these emissions is highly dependent on the source of electrical and thermal energy. However, they also cause significant greenhouse gas emissions from their transportation across the globe for processing. This study examines these minerals from the perspective of greenhouse gas avoidance, examining the location of processing as an option for reducing transportation-based and process-based emissions. The analysis proposes a “radius of reduction” to define the potential for transporting ore to reduce emissions by offshore processing. Overall scenarios for localized steel production indicate potential for 85% reduction of transport emissions in the steel industry and 14% of overall industry emissions. Local high-carbon electricity grids and inefficient production mean that the benefit of reduced transportation is partially counteracted by increased processing emissions. The transportation of all global bauxite to Norway and other nations with low-emissions electricity for production of aluminum could result in an overall reduction of industry emissions of up to 44%.

  3. Electrochemical destruction of trans-cinnamic acid by advanced oxidation processes: kinetics, mineralization, and degradation route.

    Science.gov (United States)

    Flores, Nelly; Thiam, Abdoulaye; Rodríguez, Rosa María; Centellas, Francesc; Cabot, Pere Lluís; Garrido, José Antonio; Brillas, Enric; Sirés, Ignasi

    2017-03-01

    Acidic solutions of trans-cinnamic acid at pH 3.0 have been comparatively treated by anodic oxidation with electrogenerated H2O2 (AO-H2O2), electro-Fenton (EF), and photoelectro-Fenton (PEF). The electrolytic experiments were carried out with a boron-doped diamond (BDD)/air-diffusion cell. The substrate was very slowly abated by AO-H2O2 because of its low reaction rate with oxidizing (•)OH produced from water discharge at the BDD anode. In contrast, its removal was very rapid and at similar rate by EF and PEF due to the additional oxidation by (•)OH in the bulk, formed from Fenton's reaction between cathodically generated H2O2 and added Fe(2+). The AO-H2O2 treatment yielded the lowest mineralization. The EF process led to persistent final products like Fe(III) complexes, which were quickly photolyzed upon UVA irradiation in PEF to give an almost total mineralization with 98 % total organic carbon removal. The effect of current density and substrate concentration on all the mineralization processes was examined. Gas chromatography-mass spectrometry (GC-MS) analysis of electrolyzed solutions allowed identifying five primary aromatics and one heteroaromatic molecule, whereas final carboxylic acids like fumaric, acetic, and oxalic were quantified by ion exclusion high-performance liquid chromatography (HPLC). From all the products detected, a degradation route for trans-cinnamic acid is proposed.

  4. Carbon Isotope Systematics in Mineral-Catalyzed Hydrothermal Organic Synthesis Processes at High Temperature and Pressures

    Science.gov (United States)

    Fu, Qi; Socki, R. A.; Niles, Paul B.

    2011-01-01

    Observation of methane in the Martian atmosphere has been reported by different detection techniques. Reduction of CO2 and/or CO during serpentization by mineral surface catalyzed Fischer-Tropsch Type (FTT) synthesis may be one possible process responsible for methane generation on Mars. With the evidence a recent study has discovered for serpentinization in deeply buried carbon rich sediments, and more showing extensive water-rock interaction in Martian history, it seems likely that abiotic methane generation via serpentinization reactions may have been common on Mars. Experiments involving mineral-catalyzed hydrothermal organic synthesis processes were conducted at 750 C and 5.5 Kbars. Alkanes, alcohols and carboxylic acids were identified as organic compounds. No "isotopic reversal" of delta C-13 values was observed for alkanes or carboxylic acids, suggesting a different reaction pathway than polymerization. Alcohols were proposed as intermediaries formed on mineral surfaces at experimental conditions. Carbon isotope data were used in this study to unravel the reaction pathways of abiotic formation of organic compounds in hydrothermal systems at high temperatures and pressures. They are instrumental in constraining the origin and evolution history of organic compounds on Mars and other planets.

  5. Mineralization of flumequine in acidic medium by electro-Fenton and photoelectro-Fenton processes.

    Science.gov (United States)

    Garcia-Segura, Sergi; Garrido, José A; Rodríguez, Rosa M; Cabot, Pere L; Centellas, Francesc; Arias, Conchita; Brillas, Enric

    2012-05-01

    The mineralization of flumequine, an antimicrobial agent belonging to the first generation of synthetic fluoroquinolones which is detected in natural waters, has been studied by electrochemical advanced oxidation processes (EAOPs) like electro-Fenton (EF) and photoelectro-Fenton (PEF) with UVA light. The experiments were performed in a cell containing a boron-doped diamond (BDD) anode and an air-diffusion cathode to generate H(2)O(2) at constant current. The Fe(2+) ion added to the medium increased the solubility of the drug by the formation of a complex of intense orange colour and also reacted with electrogenerated H(2)O(2) to form hydroxyl radical from Fenton reaction. Oxidant hydroxyl radicals at the BDD surface were produced from water oxidation. A partial mineralization of flumequine in a solution near to saturation with optimum 2.0mM Fe(2+) at pH 3.0 was achieved by EF. The PEF process was more powerful, giving an almost total mineralization with 94-96% total organic carbon removal. Increasing current accelerated both treatments, but with decreasing mineralization current efficiency. Comparative treatments using a real wastewater matrix led to similar degradation degrees. The kinetics for flumequine decay always followed a pseudo-first-order reaction and its rate constant, similar for both EAOPs, raised with increasing current. Generated carboxylic acids like malonic, formic, oxalic and oxamic acids were quantified by ion-exclusion HPLC. Fe(III)-oxalate and Fe(III)-oxamate complexes were the most persistent by-products under EF conditions and their quicker photolysis by UVA light explains the higher oxidation power of PEF. The release of inorganic ions such as F(-), NO(3)(-) and in lesser extent NH(4)(+) was followed by ionic chromatography. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Assessment of hydrothermal processes associated with Proterozoic mineral systems in Finland using self-organizing maps.

    Science.gov (United States)

    Lerssi, J.; Sorjonen-Ward, P.; Fraser, S. J.; Ruotsalainen, A.

    2009-04-01

    An increasingly urgent challenge in mineral system analysis is to extract relevant information from diverse datasets, and to effectively discriminate between "hydrothermal noise" and alteration and structures that may relate to significant mineralization potential. The interpretation of geophysical data is notorious for the problem of ambiguity in defining source dimensions and geometry. An additional issue, which also applies to geochemical and hyperspectral datasets, in terrain that has been overprinted by several tectonic, metamorphic and hydrothermal events, is that while anomalies represent the sum of geological processes affecting an area, we are usually interesting in extracting the signals diagnostic of a mineralizing event. Spatial analysis using weights of evidence, fuzzy logic and neural networks have been widely applied to mineral prospectivity assessment in recent years. Here however, we present an alternative, albeit complementary approach, based on the concept of self-organizing maps [1], in which natural patterns in large, unstructured datasets are derived, correlated and readily visualized, provides an alternative approach to analysis of geophysical and geochemical anomalies and integration with other geological data. We have applied SiroSOM software to airborne and ground magnetic, EM and radiometric data for two mutually adjacent areas in eastern Finland that have superficially similar structural architecture and geophysical expression, yet differ significantly in terms of mineral system character: (1) the Outokumpu Cu-Co-Zn-Ni system, hosted by metamorphosed serpentinites and their hydrothermal derivatives, which are usually highly magnetic due to both magnetite and pyrrhotite; (2) the Hammaslahti Cu-Zn system, hosted by coarse-clastic turbidites intercalated with mafic volcanics and graphitic pelites having characteristically intense magnetic and EM responses. Although the initial stage of the analysis is unsupervised, ongoing iteration and

  7. An empirical determination of concepts contributing to successful performance of a science process: A study of mineral classification

    Science.gov (United States)

    Finley, Fred N.

    Recent developments in the philosophy of science and cognitive psychology suggest that students' abilities to use science processes effectively may be greatly influenced by their knowledge of relevant concepts. The central objective of this study was to determine the extent to which students' knowledge of concepts relevant to mineral classification influenced their ability to classify minerals. A second objective was to determine which concepts are most influential. Thirty-five eighth grade earth science students were tested regarding their ability to classify minerals correctly (the dependent variable) and their knowledge of mineral hardness, cleavage, luster, streak, and the logic of the classification scheme (the independent variables). This was done following their normal classroom instruction. The results of the data analysis using an all-possible regressions procedure showed that 58.7% of the variance in correct mineral classifications was accounted for by students' knowledge of relevant concepts. Mineral hardness and cleavage were particularly important. These results suggest that students' knowledge of relevant concepts substantially influences their ability to perform the science process of mineral classification. In particular, mineral hardness and cleavage should be emphasized during instruction. The results also suggest that the presently used conception of science processes as being independent of conceptual knowledge needs to be examined and researched further.

  8. Mineral Properties and Dietary Value of Raw and Processed Stinging Nettle (Urtica dioica L.

    Directory of Open Access Journals (Sweden)

    Laban K. Rutto

    2013-01-01

    Full Text Available Stinging nettle (Urtica dioica L. has a long history of usage and is currently receiving attention as a source of fiber and alternative medicine. In many cultures, nettle is also eaten as a leafy vegetable. In this study, we focused on nettle yield (edible portion and processing effects on nutritive and dietary properties. Actively growing shoots were harvested from field plots and leaves separated from stems. Leaf portions (200 g were washed and processed by blanching (1 min at 96–98°C or cooking (7 min at 98-99°C with or without salt (5 g·. Samples were cooled immediately after cooking and kept in frozen storage before analysis. Proximate composition, mineral, amino acid, and vitamin contents were determined, and nutritive value was estimated based on 100 g serving portions in a 2000 calorie diet. Results show that processed nettle can supply 90%–100% of vitamin A (including vitamin A as β-carotene and is a good source of dietary calcium, iron, and protein. We recommend fresh or processed nettle as a high-protein, low-calorie source of essential nutrients, minerals, and vitamins particularly in vegetarian, diabetic, or other specialized diets.

  9. Peroxone mineralization of chemical oxygen demand for direct potable water reuse: Kinetics and process control.

    Science.gov (United States)

    Wu, Tingting; Englehardt, James D

    2015-04-15

    Mineralization of organics in secondary effluent by the peroxone process was studied at a direct potable water reuse research treatment system serving an occupied four-bedroom, four bath university residence hall apartment. Organic concentrations were measured as chemical oxygen demand (COD) and kinetic runs were monitored at varying O3/H2O2 dosages and ratios. COD degradation could be accurately described as the parallel pseudo-1st order decay of rapidly and slowly-oxidizable fractions, and effluent COD was reduced to below the detection limit (water, and a relationship is proposed and demonstrated to estimate the pseudo-first order rate constant for design purposes. At this O3/H2O2 mass ratio, ORP and dissolved ozone were found to be useful process control indicators for monitoring COD mineralization in secondary effluent. Moreover, an average second order rate constant for OH oxidation of secondary effluent organics (measured as MCOD) was found to be 1.24 × 10(7) ± 0.64 × 10(7) M(-1) S(-1). The electric energy demand of the peroxone process is estimated at 1.73-2.49 kW h electric energy for removal of one log COD in 1 m(3) secondary effluent, comparable to the energy required for desalination of medium strength seawater. Advantages/disadvantages of the two processes for municipal wastewater reuse are discussed.

  10. Hydrothermal processing of MSWI fly ash--towards new stable minerals and fixation of heavy metals.

    Science.gov (United States)

    Bayuseno, A P; Schmahl, W W; Müllejans, Th

    2009-08-15

    A hydrothermal processing strategy of MSWI fly ash is presented for obtaining stable minerals with low toxic potential. Different hydrothermal conditions were tested to obtain high yields of new stable minerals. Experimental parameters including temperature, nature and molarity of alkali reagents, and reaction time were evaluated. The chemical stability of hydrothermal products was examined by the toxicity characteristic leaching procedure (TCLP) test and subsequent XRD for the leached residue. The significant amounts of Al-substituted 11A tobermorite and katoite in addition to minor amounts of zeolites were formed under experimental conditions at 0.5M NaOH, 180 degrees C for 48 h, however KOH treatment in a similar regime resulted in smaller amounts of Al-substituted 11A tobermorite and katoite. Similarly, a product of mixed Al-substituted 11A tobermorite and katoite could be formed from the washed fly ash treated in 0.5M NaOH at 180 degrees C for 48 h. Under the acidic condition, the treated fly ash exhibited an excellent stability of the mineral assemblage and less release of heavy metals relative to the untreated parent materials.

  11. The utilization natural mineral in the process of palm oil glycerolysis

    Science.gov (United States)

    Mujdalipah, Siti

    2015-09-01

    The reaction of glycerolysis currently has weakness, which uses a catalyst with a high price and performed at a high temperature. Indonesia is rich in minerals that have the potential to be used as a catalyst. Besides that, the solvent allows the glycerolysis reaction done in a low temperature so that it can maintain the quality of product. The purpose of this research is to study the influence of a type of solvent and a type of natural mineral to the chemistry and physical characteristic of palm oil glycerolysis product. The research activity consists of four steps. The first is the analysis of chemistry characteristics of palm oil. The second is the process of palm oil as the effect of a type of solvent and a type of natural mineral factors. The third is the analysis of chemistry and physical characteristics of glycerolysis product. The last is the analysis of data. Based on the analysis variant at α=0.05, it shows that type of solvent and type of natural mineral doesnot influence significantly to the ability of glycerolysis product in decreasing the water surface tension and to the free glycerol content. The best product is able to decrease the water surface tension from 44.933 dyne/cm to 29.00 dyne/cm. It contains the free glycerol content of 1.30%, 1-monoglyceride content of 43.10%, acid number of 0.146 mg KOH/g sample, and it has simillar fatty acid composition with the raw material.

  12. Assessing the addition of mineral processing waste to green waste-derived compost: an agronomic, environmental and economic appraisal.

    Science.gov (United States)

    Jones, D L; Chesworth, S; Khalid, M; Iqbal, Z

    2009-01-01

    The overall aim of this study was to evaluate the benefit of mixing two large volume wastes, namely mineral processing waste and source-segregated green waste compost, on the growth performance of plants targeted towards high (horticulture/agriculture) and low (amenity/restoration) value markets. The secondary aims were to evaluate the influence of mineral waste type on plant growth performance and to undertake a simple economic analysis of the use of mineral-compost mixtures in land restoration. Our results showed that in comparison to organic wastes, mineral wastes contained a low available nutrient content which reduces compost quality. This is supported by growth trials with tomato, wheat and grass which showed that, irrespective of mineral source, plants performed poorly in compost blended with mineral waste in comparison to those grown in green waste or peat-based compost alone. In terms of consumer confidence, unlike other wastes (e.g. biosolids and construction/demolition waste) the mineral quarry wastes can be expected to be free of potentially toxic elements, however, the production costs of compost-mineral waste mixtures and subsequent transport costs may limit its widespread use. In addition, handling of the material can be difficult under wet conditions and effective blending may require the purchase of specialist equipment. From our results, we conclude that mineral fines may prove useful for low quality, low value landscaping activities close to the source of production but are unsuited to high value markets.

  13. Application of electrochemical advanced oxidation processes to the mineralization of the herbicide diuron.

    Science.gov (United States)

    Pipi, Angelo R F; Sirés, Ignasi; De Andrade, Adalgisa R; Brillas, Enric

    2014-08-01

    Here, solutions with 0.185mM of the herbicide diuron of pH 3.0 have been treated by electrochemical advanced oxidation processes (EAOPs) like electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF) or solar PEF (SPEF). Trials were performed in stirred tank reactors of 100mL and in a recirculation flow plant of 2.5L using a filter-press reactor with a Pt or boron-doped diamond (BDD) anode and an air-diffusion cathode for H2O2 electrogeneration. Oxidant hydroxyl radicals were formed from water oxidation at the anode and/or in the bulk from Fenton's reaction between added Fe(2+) and generated H2O2. In both systems, the relative oxidation ability of the EAOPs increased in the sequence EO-H2O2processes were more powerful due to the photolysis of intermediates by UV radiation. In the stirred tank reactor, the PEF treatment with BDD was the most potent method, yielding 93% mineralization after 360 min at 100 mA cm(-2). In the flow plant, the SPEF process attained a maximum mineralization of 70% at 100 mA cm(-2). Lower current densities slightly reduced the mineralization degree in SPEF, enhancing the current efficiency and dropping the energy consumption. The diuron decay always obeyed a pseudo-first-order kinetics, with a much greater apparent rate constant in EF and SPEF compared to EO-H2O2. Oxalic and oxamic acids were detected as final carboxylic acids. Ammonium and chloride ions were also released, the latter ion being partially converted into chlorate and perchlorate ions at the BDD surface.

  14. Final Regulatory Determination for Special Wastes From Mineral Processing (Mining Waste Exclusion) - Federal Register Notice, June 13, 1991

    Science.gov (United States)

    This action presents the Agency's final regulatory determination required by section 3001(b)(3)(C) of the Resource Conservation and Recovery Act (RCRA) for 20 special wastes from the processing of ores and minerals.

  15. Mineral-Water Interface Processes Affecting Uranium Fate in Contaminated Sediments

    Science.gov (United States)

    Catalano, J. G.

    2011-12-01

    Widespread uranium contamination of soil, sediments, and groundwater systems has resulted from mining activities, nuclear weapon production, and energy generation. The fate and transport of uranium in such systems is strongly affected by geochemical processes occurring at mineral-water interfaces. I will present a summary of the mineral-water interface processes found to affect uranium fate in example contaminated sediments at the U.S. Department of Energy's Hanford sites and in related model systems. Processes occurring under oxic conditions will be the primary focus of this talk as under these conditions uranium is most mobile and thus presents the greatest hazard. Three dominant solid-phase uranium species are observed in contaminated soil and sediments at the Hanford site: uranyl silicates, uranyl phosphates, and uranyl adsorbed to clays and iron oxides. In deep sediments, uranyl silicates are found in microfractures in feldspar grains, likely because slow diffusion in such fractures maintains a high silicate activity. Such silicates are also found in waste-impacted shallow sediments and soil; waste fluids or evaporative processes may have generated the silicate activity needed to produce such phases. Uranyl phosphates are less abundant, occurring primarily in shallow sediments exposed to P-bearing waste fluids. However, remediation approaches under consideration may produce substantial quantities of uranyl phosphates in the future. Adsorbed uranyl is dispersed throughout contaminated soils and shallow sediments and likely has the greatest potential for remobilization. Analogue studies show that precipitation of uranyl phosphates is rapid when such phases are supersaturated and that both homogeneous and heterogeneous nucleation may occur. Specific adsorption of uranyl to minerals is strongly affected by the presence of complexation anions. Carbonate suppresses uranyl adsorption but also forms uranyl-carbonate ternary surface complexes. At conditions below

  16. Atmospheric Processing of Iron-Containing Mineral Dust Aerosol: A Major Source of Bioavailable Iron to Ocean Life

    Science.gov (United States)

    Rubasinghege, G. R. S.; Hurub, O. A.

    2015-12-01

    In the present day, it has become more apparent that redox reactions involving mineral dust are of great interest, especially for Fe-containing mineral dust, as they transported and deposited into certain regions of the ocean that dissolved iron is often a limiting nutrient for ocean life. Given that heterogeneous reactions of Fe-containing mineral dust with acidic gases and their precursors, i.e. HNO3, dimethyl sulfide( DMS), lead to lower pH environments, the amount of bioavailable iron can increase as they are transported through the atmosphere. The current work focuses on chemical and photochemical processing of Fe-containing mineral dust particles in the presence of HNO3, SO2 and DMS under atmospherically relevant conditions. Here, various spectroscopic methods are combined with dissolution measurements to investigate atmospheric processing of iron containing aerosol dust, with a specific focus on mineralogy and environmental conditions, i.e. pH, relative humidity, temperature and solar flux. Ilmenite (FeTiO3) is used as one of the proxies for Fe-containing minerals that have enough complexity to mimic the mineral dust, yet simple enough to know the details of the reaction pathways. During these studies, above factors are found to play significant roles in the dissolution of iron from mineral dust aerosol. More importantly, data suggest that presence of titanium in the lattice structure of ilmenite enhances iron dissolution, at least by 3-fold in a comparison with hematite. Further, growth and activity of ocean diatoms (Cyclotella meneghiniana) are monitored in the presence of Fe-containing mineral dust under the same conditions. Here, diatoms are added to the reactors containing pre-dissolved iron from a prior 48hr reaction. Results show a high correlation between the growth of diatoms and the amount of bioavailable from iron containing minerals. The current study thus highlights these important, yet unconsidered, factors in the atmospheric processing of iron

  17. Dyes wastewater treatment by reduction-oxidation process in an electrochemical reactor packed with natural manganese mineral

    Institute of Scientific and Technical Information of China (English)

    WANG Ai-min; QU Jiu-hui; LIU Hui-juan; LEI Peng-ju

    2006-01-01

    A novel technology which combined electrochemical process catalyzed by manganese mineral with electro-assisted coagulation process was proposed in this study. The mineralization of organic pollutant from simulated dye wastewater containing an azo dye Acid Red B(ARB) was experimentally investigated using this method. It was found that the manganese mineral could catalyze the electrochemical process dramatically. The TOC removal percentage of electrochemical treatment catalyzed by manganese mineral was 43.6% while the TOC removal percentage of the process using the manganese mineral alone and using the electrolysis alone were 9.3% and 20.8%, respectively. Moreover, it was found that combined electroxidation with electro-assisted coagulation process could more effectively eliminate ARB. After a period of 180 min electrooxidation and 300 min electroreduction, almost 66.9% of TOC was removed, and the dissolved Mn2+ could be effectivly removed. The effects of the order of oxidation and reduction, the proper ratio electrooxidation/reduction time, and current density on the removal efficiency were investigated in detail. In addition, a proposed mechanism of manganese-mineral-catalyzed electrooxidation-reduction process was discussed in this paper.

  18. Quantifying atmospheric processing of mineral dust as a source of bioavailable phosphorus to the open oceans

    Science.gov (United States)

    Herbert, Ross; Stockdale, Anthony; Carslaw, Ken; Krom, Michael

    2016-04-01

    The transport and deposition of mineral dust is known to be the dominant source of phosphorus (P) to the surface waters of the open oceans. However, the fraction of this P that is deemed available for primary productivity remains a key uncertainty due to a limited understanding of the processes occurring during transport of the dust. Through a series of detailed laboratory experiments using desert dust and dust precursors, we show that the dissolution behaviour of P in these samples is controlled by a surface-bound labile pool, and an additional mineral pool primarily consisting of apatite. The acid dissolution of the apatite occurs rapidly and is controlled by the absolute number of H+ ions present in the solution surrounding the dust. Using these results we develop a new conceptual model that reproduces the major processes controlling P dissolution in the atmosphere. We then use a global aerosol microphysics model with a global soil database to quantify the deposition of bioavailable P to the open oceans and ice sheets. We show that, globally, the labile pool contributes 2.4 Gg P a-1 to the oceans and, from a potential pool of 11.5 Gg P a-1, the dissolved apatite pool contributes 0.24 Gg P a-1. A series of sensitivity studies identifying sources of acid in the atmosphere show that anthropogenic emissions of SO2 contribute 61% of the global mass of dissolved apatite, volcanic events contribute 11%, and DMS emissions contribute 10%. Finally, we show that the fraction of mineral dust P that is available for primary productivity varies, regionally, from 50% in the South Pacific Ocean; this explains the variability in the fraction of bioavailable P commonly observed in important oceanic regions.

  19. An economic analysis of the Jim Bridger Power Plant carbon dioxide mineralization process

    Science.gov (United States)

    Christensen, Mikol Hans

    Concerns for rising levels of CO2 in the atmosphere have lead to a myriad of schemes to reduce emissions. Many of these are complicated, expensive, and untried. Coal-fired electrical generation accounts for about 49 percent of U.S. electricity generation. Shifting generation capacity away from coal is the goal of many, yet as this statistic shows, the U.S. has a heavy dependency on coal-fired base-load generation. What is needed is a way to retrofit existing coal fired power plants to mitigate at least some of the giga-tonnes of CO2 released annually. Carbon Capture and Storage in association with greenhouse gases are a major concern in the world today. This thesis is an outgrowth of a research partnership between the University of Wyoming and the Jim Bridger Power Plant (Rocky Mountain Power) to develop a process for capture and mineralization of flue gas carbon dioxide (CO 2) using an accelerated mineral carbonization process with fly ash particles as the absorbent. This process may have several advantages over other approaches because it is an environmentally acceptable, single step process occurring at near ambient pressures and temperatures that can compliment conventional CCS processes. In addition the use of fly ash particles as an absorbent avoids the costs of processing or engineering an absorbent. The purpose of this thesis is to evaluate the capture costs and economic feasibility of the mineralization process. Two models were used to estimate the capture costs and economic feasibility of the Jim Bridger Power Plant CO2 Mineralization Project (JBP). The first was a cost of capture model which was used to estimate CO2 capture costs and how changes in the CO2 to ash capture ratio and quantities of CO2 captured affect capture costs. The second was a financial feasibility model which considered the time value of money. This second model considered the net present value (NPV) and internal rate of return (IRR) for the process using different pricing scenarios

  20. Mineral processing technologies used to obtain valuable components of the solid wastes from coal combustion in power plants

    Directory of Open Access Journals (Sweden)

    Martin Sisol

    2005-11-01

    Full Text Available This paper presents mineral processing technologies used to achieve components from solid wastes of coal combusted in power plants. By combusting bituminous coal in smelting boilers, mineral novelties are formed which are separable by suitable mineral processing technologies. The separation of unburned coal residues is realized by flotation, using nonionic flotation agents such as Flotalex MR, Flotalex bio, Flotakol NX and others. The Fe component created by the mineral novelty of magnetite is obtained by wet and dry low-intensity magnetic separation. Optimal results were accomplished by the flotation process in which we obtained residues of unburned coal. The waste from the flotation was consequently separated by the wet low-intensity separation. The waste from the flotation and magnetic separation - subtilized fly ash, contained 0 – 2,5% LOI which can be used in architecture.

  1. The effect of meat cuts and thermal processing on selected mineral concentration in beef from Holstein-Friesian bulls.

    Science.gov (United States)

    Czerwonka, Małgorzata; Szterk, Arkadiusz

    2015-07-01

    The impact of meat cuts (nine muscles and liver) and thermal processing on selected mineral (potassium, sodium, phosphorus, magnesium, zinc, iron, including heme form) concentration in beef from Holstein-Friesian bulls was evaluated in the present study. The mineral's content widely varied depending on the tissue type (skeletal muscles/liver, except zinc) and between the different bovine muscles. The greatest diversity between the muscles demonstrated was zinc (3.5-6.9 mg 100 g(-1)f/w) and iron (1.7-2.3 mg 100 g(-1)f/w), however, there were no significant differences in heme iron to total iron ratio (average 74%). Thermal processes conducted on longissimus dorsi muscles also significantly affected mineral concentration. Grilled, roasted and fried bovine meat was characterised by a higher content (by 6-26%) of most studied minerals (except sodium) as compared to raw meat. Sodium levels in processed meat were 16-33% lower than in raw samples.

  2. Managing the potential risks of using bacteria-laden water in mineral processing to protect freshwater.

    Science.gov (United States)

    Liu, Wenying; Moran, Chris J; Vink, Sue

    2013-06-18

    The minerals industry is being driven to access multiple water sources and increase water reuse to minimize freshwater withdrawal. Bacteria-laden water, such as treated effluent, has been increasingly used as an alternative to freshwater for mineral processing, in particular flotation, where conditions are favorable for bacterial growth. However, the risk posed by bacteria to flotation efficiency is poorly understood. This could be a barrier to the ongoing use of this water source. This study tested the potential of a previously published risk-based approach as a management tool to both assist mine sites in quantifying the risk from bacteria, and finding system-wide cost-effective solutions for risk mitigation. The result shows that the solution of adjusting the flotation chemical regime could only partly control the risk. The second solution of using tailings as an absorbent was shown to be effective in the laboratory in reducing bacterial concentration and thus removing the threat to flotation recovery. The best solution is likely to combine internal and external approaches, that is, inside and outside processing plants. Findings in this study contribute possible methods applicable to managing the risk from water-borne bacteria to plant operations that choose to use bacteria-containing water, when attempting to minimize freshwater use, and avoiding the undesirable consequences of increasing its use.

  3. [Purification of the wastewater of quartz processing by mineral-based porous granulation material].

    Science.gov (United States)

    Wang, En-Wen; Lei, Shao-Min; Zhang, Shi-Chun; Huang, Teng

    2015-03-01

    A mineral-based porous granulation material (MPGM) was prepared for absorbing the heavy metal ions from quartz processing wastewater. Analytic results of the MPGM were illustrated by the techniques of BET, SEM and FT-IR, which revealed the excellent properties of multi-aperture distribution, large specific surface area, low loss ratio and so on; the N2 adsorption-desorption isotherm was type-III with H4 hysteresis loop; the functional groups were dominated by groups of layer silicate mineral. A batch adsorption study was carried out with varied adsorbent dosage, initial pH and reaction time. The results showed that the residual ion concentrations of Fe, Zn, Mn and As were decreased from 77.760, 3.700, 2.789 and 0.963 mg x L(-1) to 3.421, 0.574, 0.126 and 0.034 mg x L(-1), respectively. MPGM might be re-utilized after desorption by 1.0 mol x L(-1) NaCl for 12 hours, and the ideal adsorption performance was maintained after 5 recyclings. The adsorption equilibrium and kinetics followed Langmuir and typical pseudo-first-order/pseudo-second-order adsorption models. Thermodynamic parameters of ΔG(θ) 0, ΔSθ > 0 showed that the adsorptions were spontaneous and endothermic processes in the temperature range of 15-45 degrees C.

  4. Predicting the Mineral Composition of Dust Aerosols. Part 2; Model Evaluation and Identification of Key Processes with Observations

    Science.gov (United States)

    Perlwitz, J. P.; Garcia-Pando, C. Perez; Miller, R. L.

    2015-01-01

    A global compilation of nearly sixty measurement studies is used to evaluate two methods of simulating the mineral composition of dust aerosols in an Earth system model. Both methods are based upon a Mean Mineralogical Table (MMT) that relates the soil mineral fractions to a global atlas of arid soil type. The Soil Mineral Fraction (SMF) method assumes that the aerosol mineral fractions match the fractions of the soil. The MMT is based upon soil measurements after wet sieving, a process that destroys aggregates of soil particles that would have been emitted from the original, undisturbed soil. The second method approximately reconstructs the emitted aggregates. This model is referred to as the Aerosol Mineral Fraction (AMF) method because the mineral fractions of the aerosols differ from those of the wet-sieved parent soil, partly due to reaggregation. The AMF method remedies some of the deficiencies of the SMF method in comparison to observations. Only the AMF method exhibits phyllosilicate mass at silt sizes, where they are abundant according to observations. In addition, the AMF quartz fraction of silt particles is in better agreement with measured values, in contrast to the overestimated SMF fraction. Measurements at distinct clay and silt particle sizes are shown to be more useful for evaluation of the models, in contrast to the sum over all particles sizes that is susceptible to compensating errors, as illustrated by the SMF experiment. Model errors suggest that allocation of the emitted silt fraction of each mineral into the corresponding transported size categories is an important remaining source of uncertainty. Evaluation of both models and the MMT is hindered by the limited number of size-resolved measurements of mineral content that sparsely sample aerosols from the major dust sources. The importance of climate processes dependent upon aerosol mineral composition shows the need for global and routine mineral measurements.

  5. Mineral status in canine medial coronoid process disease: a cohort study using analysis of hair by mass spectrometry.

    Science.gov (United States)

    Davies, M; West, J; Williams, C; Gardner, D S

    2017-05-06

    In several species, developmental skeletal diseases involving abnormal endochondral ossification have been associated with imbalanced mineral intake. Hair analysis reflects long-term mineral status. To determine the mineral content of hair from dogs with or without medial coronoid process disease (MCPD). Dogs with MCPD have a different profile of minerals known to influence metalloenzymes involved in endochondral ossification. After cleansing, chelation and acid digestion of hair samples (n=79 in total: control dogs, n=70 v MCPD, n=9), mineral profile (7 major and 25 trace elements) was determined by inductively coupled plasma-mass spectrometry. Dogs were of similar age (control, 4.05 [1.85-7.70] v MCPD, 4.30 [3.25-6.53] median (IQR) years; P=0.78) and gender (control, n=43/27 v MCPD, n=4/5 males/females). 28/70 (40 per cent) of control and 8/9 (88 per cent) of MCPD dogs were neutered, respectively. Hair from dogs with MCPD contained significantly lower amounts (µg/g/DM) of copper, sulphur and zinc (all at Phair mineral status. Based on hair analysis, a role for mineral imbalance including copper, sulphur and zinc in the aetiopathogenesis of canine MCPD is suggested. Hair mineral analysis may prove useful as a biomarker for susceptible puppies. British Veterinary Association.

  6. A novel process for sorting fine-sized sulphide minerals by biocoagulation

    Institute of Scientific and Technical Information of China (English)

    H.Z.KUYUMCU; J.PINKA; T.BIELIG

    2008-01-01

    Based on a process design idea,investigations at Technical University of Berlin confirm that the biocoagulation of microorganisms and solid particles would be a new method to generate coarser particles suitable for sorting.The procedure of selective biocoagulation of microorganisms,e.g.yeasts like Saccharomyces cerevisiae and Yarrowia lipolytica respectively,and micro-dispersed solids,e.g.minerals like galena and sphalerite,has been analyzed as a basis for a novel sorting process.Therefore,especially the characteristics of the cell surface of the microorganisms,e.g.the electrostatic charge and the composition of extracellular polymeric substances,as well as their influence on the selective biocoagulation were studied.Experimental investigations show that the microorganisms and the sulphide particles below 10 μm coagulate effectively.Furthermore,the flotation is suitable for the separation of the selectively formed biocoagulates.With the designed column flotation,satisfying recovery rates are reached.

  7. Potential Applications of Concentrated Solar Thermal Technologies in the Australian Minerals Processing and Extractive Metallurgical Industry

    Science.gov (United States)

    Eglinton, Thomas; Hinkley, Jim; Beath, Andrew; Dell'Amico, Mark

    2013-12-01

    The Australian minerals processing and extractive metallurgy industries are responsible for about 20% of Australia's total greenhouse gas (GHG) emissions. This article reviews the potential applications of concentrated solar thermal (CST) energy in the Australian minerals processing industry to reduce this impact. Integrating CST energy into these industries would reduce their reliance upon conventional fossil fuels and reduce GHG emissions. As CST technologies become more widely deployed and cheaper, and as fuel prices rise, CST energy will progressively become more competitive with conventional energy sources. Some of the applications identified in this article are expected to become commercially competitive provided the costs for pollution abatement and GHG mitigation are internalized. The areas of potential for CST integration identified in this study can be classed as either medium/low-temperature or high-temperature applications. The most promising medium/low-grade applications are electricity generation and low grade heating of liquids. Electricity generation with CST energy—also known as concentrated solar power—has the greatest potential to reduce GHG emissions out of all the potential applications identified because of the 24/7 dispatchability when integrated with thermal storage. High-temperature applications identified include the thermal decomposition of alumina and the calcination of limestone to lime in solar kilns, as well as the production of syngas from natural gas and carbonaceous materials for various metallurgical processes including nickel and direct reduced iron production. Hybridization and integration with thermal storage could enable CST to sustain these energy-intensive metallurgical processes continuously. High-temperature applications are the focus of this paper.

  8. Mineral deformation and subglacial processes on ice-bedrock interface of Hailuogou Glacier

    Institute of Scientific and Technical Information of China (English)

    LIU GengNian; CHEN YiXin; ZHANG Yue; FU HaiRong

    2009-01-01

    Hailuogou Glacier is located in a warm and humid maritime environment. It is large and moves very fast.The bottom of the glacier slides intensively and the temperature at the bottom approaches the pressure melting point. Therefore,there are abundant melting water and debris which act as effective "grinding tools"for glacial abrasion. Polarizing microscope is used to observe the mineral deformation characteristics on the ice-bedrock interface. It is found that feldspar,quartz,hornblende and biotite are exposed to deformation,fracture and chemical alteration to various extents. Bending deformation is common for biotite,due to their lattice characteristics,and the bending orientations are mostly the same as the glacier flow. Bending deformation also occurs in a few hornblendes. High-angle tension fracture and low-angle shear fracture are common for quartz and feldspar,some of them are totally crushed (mylonizations) due to their rigidity. Thus,all the abrasion,quarrying,subglacial water action and subglacial dissolution processes at the bottom of the glacier are verified at the micro-scale level.Mineral deformation and fracture are the basic subglacial erosion mechanisms. The abrasion thickness is 30-90 μm for each time and the average is 50 μm. Most of the debris are silt produced by glacial abrasion. The extent of mineral deformation and fracture decreases drastically downwards beneath the bedrock surface. The estimated erosion rate is about 2.2-11.4 mm/a,which is similar to that of other maritime alpine glaciers,smaller than that of large-scale piedmont glaciers In Alaska (10-30 mm/a),and larger than that of continental glaciers (0.1-1.0 mm/a). The type and size of a glacier are the main factors that influence its erosion rate.

  9. The effect of processing on total organic acids content and mineral availability of simulated cassava-vegetable diets.

    Science.gov (United States)

    Adewusi, S R; Ojumu, T V; Falade, O S

    1999-01-01

    Changes in pH, titratable acidity and mineral content (Ca, Fe, Mg, Zn) were estimated in processed cassava products while the mineral content of raw and blanched amaranthus vegetable was determined. pH of fresh cassava (6.5) decreased as total organic acid (0.07%) increased with fermentation period. Fufu and lafun had the lowest pH and the highest total organic acids contents. Fermentation of cassava increased the total calcium and iron contents, reduced magnesium level while zinc remained fairly constant in grated cassava but was reduced when soaked in water (for the preparation of fufu and lafun). Fermentation also increased the availability of these selected minerals in both cassva products and simulated cassava-vegetable diets. Blanching reduced the mineral content of amaranthus vegetable but increased mineral availability. Fermentation of cassava and blanching of vegetables play an important role in making minerals more available and these processing methods should be encouraged to potentially ameliorate the disease states associated with mineral deficiency.

  10. Modeling of atmospheric iron processing carried by mineral dust and its deposition to ocean

    Science.gov (United States)

    Nickovic, Slobodan; Vukovic, Ana; Vujadinovic, Mirjam

    2014-05-01

    Relatively insoluble iron in dust originating from desert soils increases its solubility after Fe carried by mineral dust is chemically processed by the atmosphere. After dust is deposited deposition to the ocean, soluble Fe as a nutrient could enhance the marine primary production. The atmospheric dust cycle is driven by the atmospheric processes often of smaller, meso-scales. The soil mineralogy of dust emitted from sources determines also how much Fe in the aerosol will be finding. Once Fe is exposed to the atmospheric processes, the atmospheric radiation, clouds and polluted air will chemically affect the iron in dust. Global dust-iron models, having typical horizontal resolutions of 100-300 km which are mostly used to numerically simulate the fate of iron in the atmosphere can provide rather global picture of the dust and iron transport, but not details. Such models often introduce simplistic approximation on the Fe content in dust-productive soils. To simulate the Fe processing we instead implemented a high resolution regional atmospheric dust-iron model with detailed 1km global map for the geographic distribution of Fe content in soil. We also introduced a parameterization of the Fe processing caused by dust mineralogy, cloud processes and solar radiation. We will present results from simulation experiments in order to explore the model capability to reproduce major observed patterns of deposited Fe into the Atlantic cruises.

  11. Active Mines and Mineral Processing Plants in the United States in 2003

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set includes mineral and metal operations in the United States. The data represent commodities monitored by the National Minerals Information Center of...

  12. Active Mines and Mineral Processing Plants in the United States in 2003

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set includes mineral and metal operations in the United States. The data represent commodities monitored by the National Minerals Information Center of the...

  13. Vinasse organic matter quality and mineralization potential, as influenced by raw material, fermentation and concentration processes.

    Science.gov (United States)

    Parnaudeau, V; Condom, N; Oliver, R; Cazevieille, P; Recous, S

    2008-04-01

    Both dilute and concentrated vinasse can be spread on agricultural fields or used as organic fertilizer. The effects of different characteristics of the original raw material on the biochemical composition of vinasse and their C and N mineralization in soil were investigated. Vinasse samples were obtained from similar industrial fermentation processes based on the growth of microorganisms on molasses from different raw material (sugar beet or sugar cane) and vinasse concentration (dilute or concentrated). The nature of the raw material used for fermentation had the greatest effect on the nature and size of the resistant organic pool. This fraction included aromatic compounds originating from the raw material or from complex molecules and seemed to be quantitatively related to acid-insoluble N. Samples derived from sugar beet were richer in N compounds and induced greater net N mineralization. The effect of evaporation varied with the nature of the raw material. Concentration led to a slight increase in the abundance of phenolic compounds, acid-insoluble fraction, and a slight decrease in the labile fraction of vinasses partly or totally derived from sugar beet. The effect of the dilute vinasse from sugar cane was greater. The concentrated vinasse had a smaller labile fraction, induced N immobilization at the beginning of incubation, and exhibited greater N concentration in the acid-insoluble fraction than the dilute vinasse.

  14. Coupling process study of lipid production and mercury bioremediation by biomimetic mineralized microalgae.

    Science.gov (United States)

    Peng, Yang; Deng, Aosong; Gong, Xun; Li, Xiaomin; Zhang, Yang

    2017-11-01

    Considering the high concentration of mercury in industrial wastewater, such as coal-fired power plants and gold mining wastewater, this research study investigated the coupling process of lipid production and mercury bioremediation using microalgae cells. Chlorella vulgaris modified by biomimetic mineralization. The cultivation was divided in two stages: a natural cultivation for 7days and 5days of Hg(2+) addition (10-100μg/L) for cultivation at different pH values (4-7) after inoculation. Next, the harvested cells were eluted, and lipid was extracted. The fluorescein diacetate (FDA) dye tests demonstrated that the mineralized layer enhanced the biological activity of microalgae cells in Hg(2+) contaminated media. Hg distribution tests showed that the Hg removal capacity of modified cells was increased from 62.85% to 94.74%, and 88.72% of eluted Hg(2+) concentration was observed in modified cells compared to 48.42% of raw cells, implying that more mercury was transferred from lipid and residuals into elutable forms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Importance of atmospheric aging in reactivity of mineral dust aerosol: a case study of heterogeneous reaction of gaseous hydrogen peroxide on processed mineral particles

    Directory of Open Access Journals (Sweden)

    Y. Zhao

    2011-10-01

    Full Text Available Atmospheric aging and processing appears to alter physical and chemical properties of mineral dust aerosol and thus its role as reactive surface in the troposphere. Yet, previous studies in the atmosphere have mainly focused on the clean surfaces of mineral dust aerosol, and the reactivity of aged mineral aerosol toward atmospheric trace gases is still poorly recognized. This work presents the first laboratory investigation of heterogeneous reactions of gaseous hydrogen peroxide (H2O2, an important atmospheric oxidant, on the surface of HNO3 and SO2-processed alumina particles as surrogates of mineral dust aerosol aged by acidic trace gases as a function of relative humidity (RH and surface coverage of coatings. Pretreatment of the alumina surfaces with HNO3 and SO2 has a strong impact on its reactivity toward H2O2 uptake. On HNO3-processed particles, because of the dual role of the nitrate coating in modifying the reactivity of the particle surface, namely blocking oxide active sites but altering surface hygroscopicity, H2O2 uptake seems to decrease in some cases whereas increase in other cases, largely depending on RH and surface coverage of nitrate. On SO2-processed particles, the presence of adsorbed S(IV species appears to enhance the intrinsic reactivity of the alumina particles due to its affinity for H2O2, and the uptake of H2O2 increases by 40–80% in the range of RH from 25% to 92% relative to the unprocessed particles. However, when S(IV is completely oxidized to S(VI, the alumina surface is significantly deactivated and the measured uptake of H2O2 decreased markedly. The mechanisms for heterogeneous reactions of H2O2 with these processed particles are discussed, as well as its potential implications on tropospheric

  16. Separation and Purification of Mineral Salts from Spacecraft Wastewater Processing via Electrostatic Beneficiation

    Science.gov (United States)

    Miles, John D., II; Lunn, Griffin

    2013-01-01

    Electrostatic separation is a class of material processing technologies commonly used for the sorting of coarse mixtures by means of electrical forces acting on charged or polarized particles. Most if not all of the existing tribo-electrostatic separators had been initially developed for mineral ores beneficiation. It is a well-known process that has been successfully used to separate coal from minerals. Potash (potassium) enrichment where underground salt mines containing large amounts of sodium is another use of this techno logy. Through modification this technology can be used for spacecraft wastewater brine beneficiation. This will add in closing the gap beeen traveling around Earth's Gravity well and long-term space explorations. Food has been brought on all man missions, which is why plant growth for food crops continues to be of interest to NASA. For long-term mission considerations food productions is one of the top priorities. Nutrient recovery is essential for surviving in or past low earth orbit. In our advance bio-regenerative process instead of nitrogen gas produced; soluble nitrate salts that can be recovered for plant fertilizer would be produced instead. The only part missing is the beneficiation of brine to separate the potassium from the sodium. The use of electrostatic beneficiation in this experiment utilizes the electrical charge differences between aluminum and dried brine by surface contact. The helixes within the aluminum tribocharger allows for more surface contact when being agitated. When two materials are in contact, the material with the highest affinity for electrons becomes negatively charged, while the other becomes positively charged. This contact exchange of charge may cause the particles to agglomerate depending on their residence time within the tribocharger, compromising the efficiency of separation. The aim of this experiment is to further the development in electrostatic beneficiation by optimizing the separation of ersatz and

  17. Process Mineralogy of a Low Grade Ag-Pb-Zn-CaF2 Sulphide Ore and Its Implications for Mineral Processing

    Institute of Scientific and Technical Information of China (English)

    Yalong Guo

    2014-01-01

    Based on process mineralogical study of a low-grade Ag-Pb-Zn-CaF2 sulphide ore in SW China, the occurrence of Pb and Zn, the distribution of silver minerals and their relationships with other minerals are determined in details, which provides scientific reference for the forthcoming flotation process. The mineralogical results show that four silver minerals are determined, which aftonite occupies the most. Unlike other siliver minerals which are included in lead minerals and could be enriched in lead concentrates, aftonite could be liberated as an independent mineral after grinding and may be lost in the tailings, so key factors influencing the flotation of aftonite, such as pH value of pulp, effective col ectors, etc., should be handled reasonably to get it better recovered. Besides, note that 2.1% calcite, 6.85% dolomite, which have close flotabilities to fluorite, wil also be enriched affecting the quality of the fluorite concentrates. Thus, how to depress the quartz and the calcic gangue minerals during fluorite flotation is also the key factor of the whole process.

  18. Development of Advanced Surface Enhancement Technology for Decreasing Wear and Corrosion of Equipment Used for Mineral Processing

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Tao; Craig A. Blue

    2004-08-01

    Equipment wear is a major concern in the mineral processing industry, which dramatically increases the maintenance cost and adversely affects plant operation efficiency. In this research, wear problems of mineral processing equipment including screens, sieve bends, heavy media vessel, dewatering centrifuge, etc., were identified. A novel surface treatment technology, high density infrared (HDI) surface coating process was proposed for the surface enhancement of selected mineral processing equipment. Microstructural and mechanical properties of the coated samples were characterized. Laboratory-simulated wear tests were conducted to evaluate the tribological performance of the coated components. Test results indicate that the wear resistance of AISI 4140 and ASTM A36 steels can be increased 3 and 5 folds, respectively by the application of HDI coatings.

  19. Mineralization of integrated gasification combined-cycle power-station wastewater effluent by a photo-Fenton process.

    Science.gov (United States)

    Durán, A; Monteagudo, J M; San Martín, I; Aguirre, M

    2010-09-01

    The aim of this work was to study the mineralization of wastewater effluent from an integrated-gasification combined-cycle (IGCC) power station sited in Spain to meet the requirements of future environmental legislation. This study was done in a pilot plant using a homogeneous photo-Fenton oxidation process with continuous addition of H(2)O(2) and air to the system. The mineralization process was found to follow pseudo-first-order kinetics. Experimental kinetic constants were fitted using neural networks (NNs). The NNs model reproduced the experimental data to within a 90% confidence level and allowed the simulation of the process for any values of the parameters within the experimental range studied. At the optimum conditions (H(2)O(2) flow rate=120 mL/h, [Fe(II)]=7.6 mg/L, pH=3.75 and air flow rate=1 m(3)/h), a 90% mineralization was achieved in 150 min. Determination of the hydrogen peroxide consumed and remaining in the water revealed that 1.2 mol of H(2)O(2) was consumed per each mol of total organic carbon removed from solution. This result confirmed that an excess of dissolved H(2)O(2) was needed to achieve high mineralization rates, so continuous addition of peroxide is recommended for industrial application of this process. Air flow slightly improved the mineralization rate due to the formation of peroxo-organic radicals which enhanced the oxidation process.

  20. Application of new optical coherence elastography to monitor the mineralization processing in bone tissue engineering constructs

    Science.gov (United States)

    Guan, Guangying; Song, Shaozhen; Huang, Zhihong; Yang, Ying

    2015-03-01

    Generation of functional tissue in vitro through tissue engineering technique is a promising direction to repair and replace malfunctioned organ and tissue in the modern medicine for various diseases which could not been treated well by conventional therapy. Similar to the embryo development, the generation of tissue in vitro is a highly dynamic processing. Obtaining the feedback of the processing real time is highly demanded. In this study, a new methodology has been explored aiming to monitor the morphological and mechanical property alteration of bone tissue engineering constructs simultaneously. Optical coherence elastography (OCE) equipped with a LDS V201 permanent magnet shaker and a modulated acoustic radiation force (ARF) to provide a vibration signal, has been used for the real time and non-destructive monitoring. A phantom construct system has been used to optimize the measurement conditions in which agar hydrogel with concentration from 0, 0.75 to 2% with/without hydroxyappatite particles have been injected to 3D porous poly (lactic acid) scaffolds to simulate the collagenous extracellular matrix (ECM) and mineralized ECM. The structural and elastography images of the constructs have clearly demonstrated the linear relation with the increased mechanical property versus the increase of agar concentration within the pores of the scaffolds. The MG63 bone cells seeded in the scaffolds and cultured for 4 weeks have been monitored by the established protocol exhibiting the increased mechanical strength in the pore wall where the ECM or mineralized ECM was assumed to be formed in comparison to empty pores. This study confirms that OCE-ARF could become a valuable tool in regenerative medicine to assess the biological events during in vitro culture and conditioning.

  1. Mineralization and Transfer Processes of {sup 14}C-labeled Pesticides in Outdoor Lysimeters

    Energy Technology Data Exchange (ETDEWEB)

    Grundmann, Sabine; Doerfler, Ulrike, E-mail: doerfler@gsf.de; Ruth, Bernhard; Loos, Christine [GSF - National Research Center for Environment and Health, Institute of Soil Ecology (Germany); Wagner, Tobias [GSF - National Research Center for Environment and Health, Institute of Biochemical Plant Pathology (Germany); Karl, Heidrun; Munch, Jean Charles; Schroll, Reiner [GSF - National Research Center for Environment and Health, Institute of Soil Ecology (Germany)

    2008-04-15

    A recently designed two-chamber-lysimeter-test-system allows the detailed investigation of degradation, transport and transfer processes of {sup 14}C-labeled substances in soil-plant-atmosphere-systems under outdoor conditions. With this test system it is feasible to distinguish between {sup 14}C-emissions from soil surfaces and {sup 14}C-emissions from plant surfaces in soil monoliths under real environmental conditions. Special soil humidity sensors allow the measurement of soil water content near to the soil surface, in 1 and 5 cm depth. The behavior of organic chemicals can be followed for a whole vegetation period and a mass balance for the applied chemical can be established. Some selected results of the herbicides isoproturon and glyphosate - using the two-chamber-lysimeter-test-system - are presented to demonstrate its applicability for the identification and quantification of the processes that govern pesticide behavior in soil-plant-systems. Mineralization of {sup 14}C-isoproturon was very different in four different soils; the mineralization capacity of the soils ranged from 2 to 60%. Leaching of isoproturon in general was very low, but depending on the soil type and environmental conditions isoproturon and its metabolites could be leached via preferential flow, especially shortly after application. For the herbicide {sup 14}C-glyphosate no accumulation of residues in the soil and no leaching of the residues to deeper soil layers could be observed after three applications. Glyphosate was rapidly degraded to AMPA in the soil. Glyphosate and AMPA were accumulated in soy bean nodules.

  2. Using the extended parallel process model to prevent noise-induced hearing loss among coal miners in Appalachia

    Energy Technology Data Exchange (ETDEWEB)

    Murray-Johnson, L.; Witte, K.; Patel, D.; Orrego, V.; Zuckerman, C.; Maxfield, A.M.; Thimons, E.D. [Ohio State University, Columbus, OH (US)

    2004-12-15

    Occupational noise-induced hearing loss is the second most self-reported occupational illness or injury in the United States. Among coal miners, more than 90% of the population reports a hearing deficit by age 55. In this formative evaluation, focus groups were conducted with coal miners in Appalachia to ascertain whether miners perceive hearing loss as a major health risk and if so, what would motivate the consistent wearing of hearing protection devices (HPDs). The theoretical framework of the Extended Parallel Process Model was used to identify the miners' knowledge, attitudes, beliefs, and current behaviors regarding hearing protection. Focus group participants had strong perceived severity and varying levels of perceived susceptibility to hearing loss. Various barriers significantly reduced the self-efficacy and the response efficacy of using hearing protection.

  3. Evaluation of an accelerated mineralization process for ashes - feasibility study; Evaluering av jordmaansbildande askbehandlingsprocess (EJA) - foerstudie

    Energy Technology Data Exchange (ETDEWEB)

    Ecke, Holger; Bjurstroem, Henrik

    2005-03-01

    In Japan, expenses for landfilling yield about 400 USD per ton of ash, which gives an incentive to reduce the amount of landfilled ash. At NIES (National Institute for Environmental Studies) in Tsukuba, Japan, the AMT process (Accelerated Mineralization Technology) was developed aiming at the treatment of ashes and production of soil-like material for reuse. The objective of the project EJA was to evaluate the AMT process on the basis of available information and the possibilities the process could offer with respect to the conditions present in Sweden. With support of researchers at NIES, available literature including unpublished manuscripts on the AMT process was compiled, translated and evaluated. During treatment, the ashes are washed, aged and mixed with up to 5 % by weight of biodegradable organic matter. The material is stabilized at landfill. During up to several decades, metals are demobilized through a combination of three mechanisms, viz. carbonation, clay formation, and humification. Also persistent organic pollutants (POP) are demobilized due to humification products or they are degraded anaerobically. When the treatment is completed, the reuse of the material is envisaged. Due to the long treatment period, the AMT method might not be favored by ash producers in Sweden. In the future, landfill companies could be interested in the technology, since they are experienced to handle waste at long sight. This, however, requires that the legislation does not pose any hindrance for the implementation of the method, e.g. regarding the requirement to add organic matter to the ash. Above all, it remains several years of research on the AMT process to fully understand and evaluate the underlying biological and chemical processes as well as their interaction.

  4. Isotopic investigations of dissolved organic N in soils identifies N mineralization as a major sink process

    Science.gov (United States)

    Wanek, Wolfgang; Prommer, Judith; Hofhansl, Florian

    2016-04-01

    Dissolved organic nitrogen (DON) is a major component of transfer processes in the global nitrogen (N) cycle, contributing to atmospheric N deposition, terrestrial N losses and aquatic N inputs. In terrestrial ecosystems several sources and sinks contribute to belowground DON pools but yet are hard to quantify. In soils, DON is released by desorption of soil organic N and by microbial lysis. Major losses from the DON pool occur via sorption, hydrological losses and by soil N mineralization. Sorption/desorption, lysis and hydrological losses are expected to exhibit no 15N fractionation therefore allowing to trace different DON sources. Soil N mineralization of DON has been commonly assumed to have no or only a small isotope effect of between 0-4‰, however isotope fractionation by N mineralization has rarely been measured and might be larger than anticipated. Depending on the degree of 15N fractionation by soil N mineralization, we would expect DON to become 15N-enriched relative to bulk soil N, and dissolved inorganic N (DIN; ammonium and nitrate) to become 15N-depleted relative to both, bulk soil N and DON. Isotopic analyses of soil organic N, DON and DIN might therefore provide insights into the relative contributions of different sources and sink processes. This study therefore aimed at a better understanding of the isotopic signatures of DON and its controls in soils. We investigated the concentration and isotopic composition of bulk soil N, DON and DIN in a wide range of sites, covering arable, grassland and forest ecosystems in Austria across an altitudinal transect. Isotopic composition of ammonium, nitrate and DON were measured in soil extracts after chemical conversion to N2O by purge-and-trap isotope ratio mass spectrometry. We found that delta15N values of DON ranged between -0.4 and 7.6‰, closely tracking the delta15N values of bulk soils. However, DON was 15N-enriched relative to bulk soil N by 1.5±1.3‰ (1 SD), and inorganic N was 15N

  5. Role of minerals properties on leaching process of weathered crust elution-deposited rare earth ore

    Institute of Scientific and Technical Information of China (English)

    肖燕飞; 刘向生; 冯宗玉; 黄小卫; 黄莉; 陈迎迎; 吴文远

    2015-01-01

    Granite belonged to intrusive rock and volcanic was extrusive rock. There may be many differences in their degree of weathering and mineral chemical composition. The present study investigated the minerals properties and the leaching mechanism of the granitic weathered crust elution-deposited rare earth ore from Longnan Rare Earth Mine area (LN ores) and volcanic weathered crust elution-deposited rare earth ore from Liutang Rare Earth Mine area (LT ores). The X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) were used to characterize the phase of rare earth ores. The particle size distributions and main composition of the ore were also presented in this paper. The leaching mechanisms of two kinds of rare earth ores were analyzed with different kinetics models and could be described by the shrinking-core model. They were all inner diffusion-controlled leaching processes. The leaching equation of the kinetics of the LN ores could be expressed as:4 LN LN 1.096 10 2/3 0.377 8.314 0 2 3=0.1061 (1 ) Tr e tη η×−−− − −, leaching equation of kinetics of LT ores was 3 LT LT 4.640 10 2/3 0.411 8.314 0 32 3=8.33 101 (1 ) Tr e tη η×−− −×− − −. The rare earth leaching rate of LT ores was always lower in the same condition, and it would need more time and more (NH4)2SO4 consump-tion to achieve the same rare earth leaching efficiency, which would lead to more serious ammonia-nitrogen pollution. Therefore, magnesium salt was proposed as the leaching agent to eliminate ammonia-nitrogen pollution and further studies would be taken in the future.

  6. Cloud condensation nuclei activity and droplet activation kinetics of wet processed regional dust samples and minerals

    Science.gov (United States)

    Kumar, P.; Sokolik, I. N.; Nenes, A.

    2011-08-01

    This study reports laboratory measurements of particle size distributions, cloud condensation nuclei (CCN) activity, and droplet activation kinetics of wet generated aerosols from clays, calcite, quartz, and desert soil samples from Northern Africa, East Asia/China, and Northern America. The dependence of critical supersaturation, sc, on particle dry diameter, Ddry, is used to characterize particle-water interactions and assess the ability of Frenkel-Halsey-Hill adsorption activation theory (FHH-AT) and Köhler theory (KT) to describe the CCN activity of the considered samples. Wet generated regional dust samples produce unimodal size distributions with particle sizes as small as 40 nm, CCN activation consistent with KT, and exhibit hygroscopicity similar to inorganic salts. Wet generated clays and minerals produce a bimodal size distribution; the CCN activity of the smaller mode is consistent with KT, while the larger mode is less hydrophilic, follows activation by FHH-AT, and displays almost identical CCN activity to dry generated dust. Ion Chromatography (IC) analysis performed on regional dust samples indicates a soluble fraction that cannot explain the CCN activity of dry or wet generated dust. A mass balance and hygroscopicity closure suggests that the small amount of ions (from low solubility compounds like calcite) present in the dry dust dissolve in the aqueous suspension during the wet generation process and give rise to the observed small hygroscopic mode. Overall these results identify an artifact that may question the atmospheric relevance of dust CCN activity studies using the wet generation method. Based on the method of threshold droplet growth analysis, wet generated mineral aerosols display similar activation kinetics compared to ammonium sulfate calibration aerosol. Finally, a unified CCN activity framework that accounts for concurrent effects of solute and adsorption is developed to describe the CCN activity of aged or hygroscopic dusts.

  7. Cloud condensation nuclei activity and droplet activation kinetics of wet processed regional dust samples and minerals

    Directory of Open Access Journals (Sweden)

    P. Kumar

    2011-08-01

    Full Text Available This study reports laboratory measurements of particle size distributions, cloud condensation nuclei (CCN activity, and droplet activation kinetics of wet generated aerosols from clays, calcite, quartz, and desert soil samples from Northern Africa, East Asia/China, and Northern America. The dependence of critical supersaturation, sc, on particle dry diameter, Ddry, is used to characterize particle-water interactions and assess the ability of Frenkel-Halsey-Hill adsorption activation theory (FHH-AT and Köhler theory (KT to describe the CCN activity of the considered samples. Wet generated regional dust samples produce unimodal size distributions with particle sizes as small as 40 nm, CCN activation consistent with KT, and exhibit hygroscopicity similar to inorganic salts. Wet generated clays and minerals produce a bimodal size distribution; the CCN activity of the smaller mode is consistent with KT, while the larger mode is less hydrophilic, follows activation by FHH-AT, and displays almost identical CCN activity to dry generated dust. Ion Chromatography (IC analysis performed on regional dust samples indicates a soluble fraction that cannot explain the CCN activity of dry or wet generated dust. A mass balance and hygroscopicity closure suggests that the small amount of ions (from low solubility compounds like calcite present in the dry dust dissolve in the aqueous suspension during the wet generation process and give rise to the observed small hygroscopic mode. Overall these results identify an artifact that may question the atmospheric relevance of dust CCN activity studies using the wet generation method.

    Based on the method of threshold droplet growth analysis, wet generated mineral aerosols display similar activation kinetics compared to ammonium sulfate calibration aerosol. Finally, a unified CCN activity framework that accounts for concurrent effects of solute and adsorption is developed to

  8. National information service in mining, mineral processing and extractive metallurgy. [MINTEC

    Energy Technology Data Exchange (ETDEWEB)

    Romaniuk, A.S.; MacDonald, R.J.C.

    1979-03-01

    More than a dedade ago, CANMET management recognized the need to make better use of existing technological information in mining and extractive metallurgy, two fields basic to the economic well-being of Canada. There were at that time no indexes or files didicated to disseminating technical information for the many minerals mined and processed in Canada, including coal. CANMET, with the nation's largest research and library resources in the minerals field, was in a unique position to fill this need. Initial efforts were concentrated on building a mining file beginning with identification of world sources of published information, development of a special thesaurus of terms for language control and adoption of a manual indexing/retrieval system. By early 1973, this file held 8,300 references, with source, abstract and keywords given for each reference. In mid-1973, operations were computerized. Software for indexing and retrieval by batch mode was written by CANMET staff to utilize the hardware facilities of EMR's Computer Science Center. The resulting MINTEC file, one of the few files of technological information produced in Canada, is the basis for the national literature search service in mining offered by CANMET. Attention is now focussed on building a sister-file in extractive metallurgy using the system already developed. Published information sources have been identified and a thesaurus of terms is being compiled and tested. The software developed for CANMET's file-building operations has several features, including the selective dissemination of information and production from magnetic tape of photoready copy for publication, as in a bi-monthly abstracts journal.

  9. Bioelectro-Fenton: A sustainable integrated process for removal of organic pollutants from water: Application to mineralization of metoprolol.

    Science.gov (United States)

    Olvera-Vargas, Hugo; Cocerva, Tatiana; Oturan, Nihal; Buisson, Didier; Oturan, Mehmet A

    2016-12-05

    The relevant environmental hazard related to the presence of pharmaceuticals in water sources requires the development of high effective and suitable wastewater treatment technologies. In the present work, a hybrid process coupling electro-Fenton (EF) process and aerobic biological treatment (Bio-EF process) was implemented for the efficient and cost-effective mineralization of beta-blocker metoprolol (MPTL) aqueous solutions. Firstly, operating factors influencing EF process were assessed. MTPL solutions were completely mineralized after 4h-electrolysis under optimal operating conditions and BDD anode demonstrated its oxidation superiority. The absolute rate constant of MTPL oxidation byOH (kMTPL) was determined by the competition kinetics method and found to be (1.72±0.04)×10(9)M(-1)s(-1). A reaction pathway for the mineralization of the drug was proposed based on the identification of oxidation by-products. Secondly, EF process was used as pre-treatment. An increase of BOD5/COD ratio from 0.012 to 0.44 was obtained after 1h EF treatment, along with 47% TOC removal and a significant decrease of toxicity, demonstrating the feasibility of a post-biological treatment. Finally, biological treatment successfully oxidized 43% of the total TOC content. An overall 90% mineralization of MPTL solutions was achieved by the Bio-EF process, demonstrating its potentiality for treating wastewater containing pharmaceutical residues.

  10. Method of the Aquatic Environment Image Processing for Determining the Mineral Suspension Parameters

    Directory of Open Access Journals (Sweden)

    D.A. Antonenkov

    2016-10-01

    Full Text Available The present article features the developed method to determine the mineral suspension characteristics by obtaining and following processing of the aquatic environment images. This method is capable of maintaining its performance under the conditions of considerable dynamic activity of the water masses. The method feature consists in application of the developed computing algorithm, simultaneous use of morphological filters and histogram methods for image processing, and in a special calibration technique. As a whole it provides a possibility to calculate size and concentration of the particles on the images obtained. The developed technical means permitting to get the environment images of the required quality are briefly described. The algorithm of the developed software operation is represented. The examples of numerical and weight distribution of the particles according to their sizes, and the totals of comparing the results obtained by the standard and developed methods are represented. The developed method makes it possible to obtain the particle size data in the range of 50–1000 μm and also to determine the suspension concentration with ~12 % error. This method can be technically implemented for the instruments intended for in situ measurements using the gauges, allowing obtaining exposure time short values, such as applying the electron-optical converter, which acts as the image intensifier, and the high-speed electronic shutter. The completed method testing in the laboratory makes possible to obtain the results similar in accuracy with the results of the in situ measurements.

  11. Bio-mineralization and potential biogeochemical processes in bauxite deposits: genetic and ore quality significance

    Science.gov (United States)

    Laskou, Magdalini; Economou-Eliopoulos, Maria

    2013-08-01

    The Parnassos-Ghiona bauxite deposit in Greece of karst type is the 11th largest bauxite producer in the world. The mineralogical, major and trace-element contents and δ18O, δ12C, δ34S isotopic compositions of bauxite ores from this deposit and associated limestone provide valuable evidence for their origin and biogeochemical processes resulting in the beneficiation of low grade bauxite ores. The organic matter as thin coal layers, overlying the bauxite deposits, within limestone itself (negative δ12C isotopic values) and the negative δ34S values in sulfides within bauxite ores point to the existence of the appropriate circumstances for Fe bio-leaching and bio-mineralization. Furthermore, a consortium of microorganisms of varying morphological forms (filament-like and spherical to lenticular at an average size of 2 μm), either as fossils or presently living and producing enzymes, is a powerful factor to catalyze the redox reactions, expedite the rates of metal extraction and provide alternative pathways for metal leaching processes resulting in the beneficiation of bauxite ore.

  12. Effects of fractional crystallization and cumulus processes on mineral composition trends of some lunar and terrestrial rock series

    Science.gov (United States)

    Longhi, J.

    1982-01-01

    A plot of Mg of mafic minerals versus An of plagioclase in cumulate rocks from various lunar and terrestrial rock series shows each series to have a distinct curvilinear trend. The slopes of these trends vary from nearly vertical in the case of lunar anorthosites and Mg-norites to nearly horizontal in the case of gabbros from the mid-Atlantic ridge. Calculations based upon known major element partitioning between mafic minerals, plagioclase and subalkaline basaltic liquids indicate that fractional crystallization coupled with cotectic accumulation of mafic minerals and plagioclase will produce mineral composition trends on the Mg versus An diagram with slopes greater than 1 for cases where An is approximately greater than Mg. Furthermore, fractional crystallization of basaltic magmas with alkali concentrations approaching zero will produce near vertical Mg versus An trends. Therefore, the steep slopes of the lunar rock series are consistent with relatively simple fractionation processes. The relatively flat slope of mineral compositions from gabbros collected from the mid-Atlantic ridge at 26 deg N is inconsistent with simple fractionation processes, and calculations show that periodic refilling of a fractionating magma chamber with picritic magma cannot simply explain this flat slope either.

  13. Advances in understanding mineral dust and boundary layer processes over the Sahara from Fennec aircraft observations

    Directory of Open Access Journals (Sweden)

    C. L. Ryder

    2015-01-01

    Full Text Available The Fennec climate program aims to improve understanding of the Saharan climate system through a synergy of observations and modelling. We present a description of the Fennec airborne observations during 2011 and 2012 over the remote Sahara (Mauritania and Mali and the advances in the understanding of mineral dust and boundary layer processes they have provided. Aircraft instrumentation aboard the UK FAAM BAe146 and French SAFIRE Falcon 20 is described, with specific focus on instrumentation specially developed and relevant to Saharan meteorology and dust. Flight locations, aims and associated meteorology are described. Examples and applications of aircraft measurements from the Fennec flights are presented, highlighting new scientific results delivered using a synergy of different instruments and aircraft. These include: (1 the first airborne measurement of dust particles sized up to 300 microns and associated dust fluxes in the Saharan atmospheric boundary layer (SABL, (2 dust uplift from the breakdown of the nocturnal low-level jet before becoming visible in SEVIRI satellite imagery, (3 vertical profiles of the unique vertical structure of turbulent fluxes in the SABL, (4 in-situ observations of processes in SABL clouds showing dust acting as CCN and IN at −15 °C, (5 dual-aircraft observations of the SABL dynamics, thermodynamics and composition in the Saharan heat low region (SHL, (6 airborne observations of a dust storm associated with a cold-pool (haboob issued from deep convection over the Atlas, (7 the first airborne chemical composition measurements of dust in the SHL region with differing composition, sources (determined using Lagrangian backward trajectory calculations and absorption properties between 2011 and 2012, (8 coincident ozone and dust surface area measurements suggest coarser particles provide a route for ozone depletion, (9 discrepancies between airborne coarse mode size distributions and AERONET sunphotometer

  14. Indicators for the feasibility of WEEE processing plants in brazil: a relationship between virgin mineral copper ore and the recycling of consumer electronic products

    Directory of Open Access Journals (Sweden)

    Luis Henrique Alves Cândido

    2015-07-01

    Full Text Available This paper assesses the economic analysis of the implementation of WEEE – Waste Electrical and Electronic Equipment Directive – processing plants in Brazil, through the study of potential copper extraction from this secondary source. A comparative approach was performed on its copper grade related to levels of its virgin ore mineral extracted from mines located in Brazil, in the United States and through a global average. The results demonstrate that the amount of copper mass originated from the recycling of disassembly of twenty electronic products ranges from 0.24% to 17.83% of its total mass, with an average of 3.63% of copper. In eighteen of these products, values greater than 0.4% were found, which surpass current levels of copper in ore mines in the USA. In fourteen products, these rates exceed the index of 1.5% copper in the ore, considered the minimum rate for the feasibility of opening new units of copper underground mining in Brazil. Thus, this paper shows the economic analysis that aims to guide on the viability of deploying WEEE processing plants, focusing on the expansion of recycling and reuse of copper by the processing industry.

  15. ASSESSING THE LEACHING BEHAVIOR OF METALS FROM A MINERAL PROCESSING WASTE AS A FUNCTION OF LIQUID TO SOLID RATIO

    Science.gov (United States)

    A mineral processing waste was used to study the effect of liquid to solid ratio (L/S) on the leaching behavior of metals. Leaching tests in the form of column and batch studies were carried out to investigate liquid to solid ratios ranging from 0.7 to 50. Although the waste pa...

  16. Study on mixing and segregation behaviors in particulate fluidized bed system for mineral processing

    Institute of Scientific and Technical Information of China (English)

    Sahu S.N.; Sahu A.K.; Biswal S.K

    2015-01-01

    In order to identify the mixing and segregation behaviors in a mineral processing operation, present study aimed on the hydrodynamics of solid–liquid fluidization. The study was carried out in a fluidization column with tapings at different height of the bed to collect the sample. The binary particles considered in this study are hematite (4800 kg/m3) and quartz (2600 kg/m3) at different size fractions in the range of average size 87 ? 10?6 m to 400 ? 10?6 m. It is observed that for various binary mixtures, both quartz and hematite particles share the equal composition by mass (50%) at a particular height of fluidized bed, referred as ‘locus point’ of mixing. Study indicates that the mixing zone volume will increase for a continuous fluidized bed plant operation. It is observed that the number of locus points varies from 1 to 3 signifying their dependency on the size ratios of binary mixture. Whenever, the difference in terminal velocity between quartz and hematite particles approaches to zero, mixing is enhanced. Further, the present study is extended to find the segregation index for the different size ratios of quartz and hematite particles. It is evident that depending on the size ratios, various regions such as complete segregation, partial mixing and complete mixing can be observed.

  17. Aquatic ecosystems in Central Colorado are influenced by mineral forming processes and historical mining

    Science.gov (United States)

    Schmidt, T.S.; Church, S.E.; Clements, W.H.; Mitchell, K.A.; Fey, D. L.; Wanty, R.B.; Verplanck, P.L.; San, Juan C.A.; Klein, T.L.; deWitt, E.H.; Rockwell, B.W.

    2009-01-01

    Stream water and sediment toxicity to aquatic insects were quantified from central Colorado catchments to distinguish the effect of geologic processes which result in high background metals concentrations from historical mining. Our sampling design targeted small catchments underlain by rocks of a single lithology, which allowed the development of biological and geochemical baselines without the complication of multiple rock types exposed in the catchment. By accounting for geologic sources of metals to the environment, we were able to distinguish between the environmental effects caused by mining and the weathering of different mineralized areas. Elevated metal concentrations in water and sediment were not restricted to mined catchments. Impairment of aquatic communities also occurred in unmined catchments influenced by hydrothermal alteration. Hydrothermal alteration style, deposit type, and mining were important determinants of water and sediment quality and aquatic community structure. Weathering of unmined porphyry Cu-Mo occurrences resulted in water (median toxic unit (TU) = 108) and sediment quality (TU = 1.9) that exceeded concentrations thought to be safe for aquatic ecosystems (TU = 1). Metalsensitive aquatic insects were virtually absent from streams draining catchments with porphyry Cu-Mo occurrences (1.1 individuals/0.1 m2 ). However, water and sediment quality (TU = 0.1, 0.5 water and sediment, respectively) and presence of metalsensitive aquatic insects (204 individuals/0.1 m2 ) for unmined polymetallic vein occurrences were indistinguishable from that for unmined and unaltered streams (TU = 0.1, 0.5 water and sediment, respectively; 201 individuals/0.1 m2 ). In catchments with mined quartz-sericite-pyrite altered polymetallic vein deposits, water (TU = 8.4) and sediment quality (TU = 3.1) were degraded and more toxic to aquatic insects (36 individuals/0.1 m2 ) than water (TU = 0.4) and sediment quality (TU = 1.7) from mined propylitically altered

  18. Mineral assemblages and oxygen and sulphur fugacities in natural water-rock interaction processes

    Science.gov (United States)

    D'Amore, F.; Gianelli, G.

    1984-04-01

    Several mineral assemblages capable of buffering oxygen and sulphur fugacity and theoretical calculations were used to determine the fugacities of these two gas species over a temperature range between 150° and 350°C. Computed values were compared with those calculated from the composition of the geothermal fluids of Larderello, Travale, Bagnore and Piancastagnaio (Italy), The Geysers (USA) and Cerro Prieto (Mexico). The possible hydrothermal mineral assemblages that best fit the field data are those containing minerals frequently found in many geothermal fields: epidote, chlorite, K-feldspar, quartz and pyrite. These assemblages can be used in place of the classical buffers based on iron oxides and sulphides.

  19. Combining long term field experiments and nanoscale analysis to enhance process understanding of root litter stabilization by mineral interactions

    Science.gov (United States)

    Chabbi, Abad; Baumann, Karen; Remusat, Laurent; Barre, Pierre; Dignac, Marie-France; Rumpel, Cornelia

    2015-04-01

    Mineral interaction may affect the stabilisation of root litter directly or indirectly after microbial decomposition and transformation. The importance of both processes may vary within the soil profile. In this study we studied C stabilisation of isotopically labelled root litter (13C and 15N), which was incubated during 3 year in the field at different soil depth. Samples from this field experiment were recovered and subjected to nanoscale analyses in order to elucidate mineral interactions occurring in different parts of the soil profile. Our results showed enrichment of mineral associated organic matter in subsoil horizons. However, material derived from new plant litter may be stabilised at similar rates in top- and subsoil horizons. N-containing compounds are enriched in the mineral associated fraction of subsoil horizons, indicating enrichment of microbial derived material with depth. Nano scale analyses showed that indeed plant-derived material may be associated with metal oxides in topsoil horizons, whereas the mineral associated organic matter in subsoil horizons may consist of microbial cells. Interestingly, in contrast to short term laboratory analysis, decoupling of C and N through stabilisation with soil minerals was observed during this long term field experiment. Our results indicate that the nature of OM stabilised by mineral interactions is depth specific. Therefore, we suggest, that plant derived lignocellulosic material may be preserved by mineral interactions in topsoil given its incomplete degradation, thereby leading to the formation of functional groups and favouring adsorption to soil minerals. This is consistent with the higher state of lignin-degradation observed in topsoil horizons as compared to subsoil. At depth, where microorganisms are most likely energy limited, degradation of fresh plant litter may be complete, thereby diminishing the formation of lignocellulosic compounds capable of sorption onto metal oxides. As a result

  20. Phosphate geochemistry, mineralization processes, and Thioploca distribution in shelf sediments off central Chile

    DEFF Research Database (Denmark)

    Holmkvist, Lars; Arning, Esther T.; Küster-Heins, Kathrin

    2010-01-01

    mineralization, and occurrence of dense communities of the filamentous sulfur bacteria, Thioploca spp., on the continental shelf off central Chile during the austral summer when high phytoplankton productivity and anoxic bottom water prevailed. Freshly deposited phytodetritus stimulated extremely high sulfate...

  1. Phosphate geochemistry, mineralization processes, and Thioploca distribution in shelf sediments off central Chile

    DEFF Research Database (Denmark)

    Holmkvist, Lars; Arning, Esther T.; Küster-Heins, Kathrin

    2010-01-01

    mineralization, and occurrence of dense communities of the filamentous sulfur bacteria, Thioploca spp., on the continental shelf off central Chile during the austral summer when high phytoplankton productivity and anoxic bottom water prevailed. Freshly deposited phytodetritus stimulated extremely high sulfate...

  2. A novel property of DNA - as a bioflotation reagent in mineral processing.

    Science.gov (United States)

    Vasanthakumar, Balasubramanian; Ravishankar, Honnavar; Subramanian, Sankaran

    2012-01-01

    Environmental concerns regarding the use of certain chemicals in the froth flotation of minerals have led investigators to explore biological entities as potential substitutes for the reagents in vogue. Despite the fact that several microorganisms have been used for the separation of a variety of mineral systems, a detailed characterization of the biochemical molecules involved therein has not been reported so far. In this investigation, the selective flotation of sphalerite from a sphalerite-galena mineral mixture has been achieved using the cellular components of Bacillus species. The key constituent primarily responsible for the flotation of sphalerite has been identified as DNA, which functions as a bio-collector. Furthermore, using reconstitution studies, the obligatory need for the presence of non-DNA components as bio-depressants for galena has been demonstrated. A probable model involving these entities in the selective flotation of sphalerite from the mineral mixture has been discussed.

  3. Changes in mineral concentrations and phosphorus profile during dry-grind processing of corn into ethanol.

    Science.gov (United States)

    Liu, KeShun; Han, Jianchun

    2011-02-01

    For determining variation in mineral composition and phosphorus (P) profile among streams of dry-grind ethanol production, samples of ground corn, intermediate streams, and distillers dried grains with solubles (DDGS) were obtained from three commercial plants. Most attributes (dry matter concentrations) increased significantly from corn to cooked slurry but fermentation caused most significant increase in all attributes. During centrifugation, more minerals went into thin stillage than wet grains, making minerals most concentrated in the former. Mineral increase in DDGS over corn was about 3 fold, except for Na, S, Ca, and Fe. The first three had much higher fold of increase, presumably due to exogenous addition. During fermentation, phytate P and inorganic P had 2.54 and 10.37 fold of increase over corn, respectively, while relative to total P, % phytate P decreased and % inorganic P increased significantly. These observations suggest that phytate underwent some degradation, presumably due to activity of yeast phytase.

  4. Development of Advanced Surface Enhancement Technology for Decreasing Wear and Corrosion of Equipment Used for Mineral Processing

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Tao; R. Honaker; B. K. Parekh

    2007-09-20

    Equipment wear is a major concern in the mineral processing industry, which dramatically increases the maintenance cost and adversely affects plant operation efficiency. In this research, novel surface treatment technologies, High Density Infrared (HDI) and Laser Surface Engineering (LSE) surface coating processes were developed for the surface enhancement of selected mineral and coal processing equipment. Microstructural and mechanical properties of the coated specimens were characterized. Laboratory-simulated wear tests were conducted to evaluate the tribological performance of the coated components. Test results indicate that the wear resistance of ASTM A36 (raw coal screen section) and can be significantly increased by applying HDI and LSE coating processes. Field testing has been performed using a LSE-treated screen panel and it showed a significant improvement of the service life.

  5. Development of Advanced Surface Enhancement Technology for Decreasing Wear and Corrosion of Equipment Used for Mineral Processing

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Tao; Craig A. Blue

    2006-07-20

    Equipment wear is a major concern in the mineral processing industry, which dramatically increases the maintenance cost and adversely affects plant operation efficiency. In this research, novel surface treatment technologies, High Density Infrared (HDI) and Laser Surface Engineering (LSE) surface coating processes were developed for the surface enhancement of selected mineral processing equipment. Microstructural and mechanical properties of the coated specimens were characterized. Laboratory-simulated wear tests were conducted to evaluate the tribological performance of the coated components. Test results indicate that the wear resistance of ASTM A36 (raw coal screen section) and can be significantly increased by applying HDI and LSE coating processes. Field testing has been performed using a LSE-treated screen panel and it showed a 2 times improvement of the service life.

  6. Twenty-fifth Semiannual Report of the Commission to the Congress, January 1959. Atomic Industrial Process and Second World Conference, July - December 1958

    Energy Technology Data Exchange (ETDEWEB)

    McCone, John A.

    1959-01-31

    The document represents the twenty-fifth semiannual Atomic Energy Commission (AEC) report to Congress. The report sums up the major activities and developments in the national atomic energy program in Part Three, covering the period July - December 1958. A special Part One of this semiannual report is titled ''Industrial Atomic Progress During 1958", and a Part Two entitled "Second World Conference on Peaceful Uses of Atomic Energy".

  7. A Novel Property of DNA - As a Bioflotation Reagent in Mineral Processing

    OpenAIRE

    Balasubramanian Vasanthakumar; Honnavar Ravishankar; Sankaran Subramanian

    2012-01-01

    Environmental concerns regarding the use of certain chemicals in the froth flotation of minerals have led investigators to explore biological entities as potential substitutes for the reagents in vogue. Despite the fact that several microorganisms have been used for the separation of a variety of mineral systems, a detailed characterization of the biochemical molecules involved therein has not been reported so far. In this investigation, the selective flotation of sphalerite from a sphalerite...

  8. Effect of processing and cooking on mineral and phytic acid content of buckwheat-enriched tagliatelle

    Directory of Open Access Journals (Sweden)

    Jambrec Dubravka

    2016-01-01

    Full Text Available Two types of buckwheat flour - non-treated (NBF and autoclaved (TBF were used for the enrichment of whole wheat tagliatelle (control sample at the level of 10-30% and the produced tagliatelle samples (dry and cooked were examined in terms of mineral and phytic acid (PA content. Both NBF and TBF possessed significantly higher (p < 0.05 content of all investigated minerals compared to whole wheat flour (WWF, but significantly lower (p < 0.05 PA content. Cooked NBF-containing tagliatelle possessed significantly higher (p < 0.05 content of Mg, Zn, Mn and Fe compared to the cooked control sample, while mineral content of cooked TBF-containing tagliatelle samples was not significantly different from the control. Autoclaving significantly reduced (p < 0.05 PA content of cooked TBF-containing tagliatelle samples compared to cooked NBF-containing tagliatelle samples and the control sample. The mineral bioavailability defined through molar ratio of mineral to phytate was slightly improved in buckwheat-containing tagliatelle samples, but it still remains at low level. Regarding all results, the enrichment of whole wheat tagliatelle with NBF at higher levels of substitution (20-30% resulted in significant increase in mineral content and bioavailability.

  9. Mineralogy and Geochemical Processes of Carbonate Mineral-rich Sulfide Mine Tailings, Zimapan, Mexico

    Science.gov (United States)

    McClure, R. J.; Deng, Y.; Loeppert, R.; Herbert, B. E.; Carrillo, R.; Gonzalez, C.

    2009-12-01

    Mining for silver, lead, zinc, and copper in Zimapan, Hidalgo State, Mexico has been ongoing since 1576. High concentrations of heavy metals have been found in several mine tailing heaps in the Zimapan area, with concentrations of arsenic observed as high as 28,690 mg/kg and levels of Pb as high as 2772 mg/kg. Unsecured tailings heaps and associated acid mine drainage has presented tremendous problems to revegetation, water quality, and dust emission control in the Zimapan area. Although acid mine drainage problems related to weathering of sulfide minerals have been extensively studied and are well known, the weathering products of sulfides in areas with a significant presence of carbonate minerals and their effect on the mobility of heavy metals warrant further study. Carbonate minerals are expected to neutralize sulfuric acid produced from weathering of sulfide minerals, however, in the Zimapan area localized areas of pH as low as 1.8 were observed within carbonate mineral-rich tailing heaps. The objectives of this study are to characterize (1) the heavy metal-containing sulfide minerals in the initial tailing materials, (2) the intermediate oxidation products of sulfide minerals within the carbonate-rich tailings, (3) chemical species of heavy metals within pH gradients between 1.8 and 8.2, the approximate natural pH of limestone, and (4) the mobility of soluble and colloidal heavy metals and arsenic within the carbonate-rich tailings. Representative mine tailings and their intermediate oxidation products have been sampled from the Zimapan area. Mineralogical characterization will be conducted with X-ray diffraction, infrared spectroscopy, electron microscopes and microprobes, and chemical methods. Chemical species will be extracted by selective dissolution methods. Preliminary results have identified calcite as the dominant mineral in the tailing heaps with a pH of 7, suggesting non-equilibrium with the acidic weathering products. Other minerals identified in

  10. Mineralization and leaching process in the Jian copper deposit, northeastern Fars province: Application of petrography and stable isotopes

    Directory of Open Access Journals (Sweden)

    Farid Moore

    2015-04-01

    Full Text Available Introduction One of the first principles in the formation of a reserve is mineralogical, construction and mineral textures studies and investigation of paragenetic relations in the ore minerals. In addition, to petrographic studies, isotopic investigates have wide applications in economic geology. In general, copper isotope variability in primary (high temperature mineralization forms a tight cluster, in contrast to secondary mineralization, which has a much larger isotope range. A distinct pattern of heavier copper isotope signatures is evident in supergene samples, and a lighter signature characterizes the leached cap and oxidation-zone minerals. This relationship has been used to understand oxidation–reduction processes (Hoefs, 2009. Also for a better understanding of the origin of the Jian Cu deposit, this research focuses on the origin and composition of the fluid and elucidation of its evolution during the mineralization process. In order to achieve this end, field observations, vein petrography, microthermometry of fluid inclusions and stable isotope analyses of veins and minerals were investigated. The present study also compares high and low temperature sulfide samples in an attempt to document and explain diagnostic δ65Cu ranges in minerals from the Jian deposit. Materials and methods The samples were taken from different depths to measure Cu isotope variations within each reservoir. Mineralogical composition was determined using X-ray diffractometry. In addition, chromatographic separation was carried out on all samples (except for native Cu samples in a clean lab and was conducted as outlined in Mathur et al. (Mathur et al., 2009. These samples were measured into a Multicollector Inductively-Coupled-Plasma Mass Spectrometer (MC-ICPMS, the Micro mass Isoprobe at the University of Arizona in low resolution mode using a microconcentric nebulizer to increase sensitivity for the samples with lower concentrations of copper. Preparation

  11. Advances in understanding mineral dust and boundary layer processes over the Sahara from Fennec aircraft observations

    Science.gov (United States)

    Ryder, C. L.; McQuaid, J. B.; Flamant, C.; Rosenberg, P. D.; Washington, R.; Brindley, H. E.; Highwood, E. J.; Marsham, J. H.; Parker, D. J.; Todd, M. C.; Banks, J. R.; Brooke, J. K.; Engelstaedter, S.; Estelles, V.; Formenti, P.; Garcia-Carreras, L.; Kocha, C.; Marenco, F.; Sodemann, H.; Allen, C. J. T.; Bourdon, A.; Bart, M.; Cavazos-Guerra, C.; Chevaillier, S.; Crosier, J.; Darbyshire, E.; Dean, A. R.; Dorsey, J. R.; Kent, J.; O'Sullivan, D.; Schepanski, K.; Szpek, K.; Trembath, J.; Woolley, A.

    2015-07-01

    The Fennec climate programme aims to improve understanding of the Saharan climate system through a synergy of observations and modelling. We present a description of the Fennec airborne observations during 2011 and 2012 over the remote Sahara (Mauritania and Mali) and the advances in the understanding of mineral dust and boundary layer processes they have provided. Aircraft instrumentation aboard the UK FAAM BAe146 and French SAFIRE (Service des Avions Français Instrumentés pour la Recherche en Environnement) Falcon 20 is described, with specific focus on instrumentation specially developed for and relevant to Saharan meteorology and dust. Flight locations, aims and associated meteorology are described. Examples and applications of aircraft measurements from the Fennec flights are presented, highlighting new scientific results delivered using a synergy of different instruments and aircraft. These include (1) the first airborne measurement of dust particles sizes of up to 300 microns and associated dust fluxes in the Saharan atmospheric boundary layer (SABL), (2) dust uplift from the breakdown of the nocturnal low-level jet before becoming visible in SEVIRI (Spinning Enhanced Visible Infra-Red Imager) satellite imagery, (3) vertical profiles of the unique vertical structure of turbulent fluxes in the SABL, (4) in situ observations of processes in SABL clouds showing dust acting as cloud condensation nuclei (CCN) and ice nuclei (IN) at -15 °C, (5) dual-aircraft observations of the SABL dynamics, thermodynamics and composition in the Saharan heat low region (SHL), (6) airborne observations of a dust storm associated with a cold pool (haboob) issued from deep convection over the Atlas Mountains, (7) the first airborne chemical composition measurements of dust in the SHL region with differing composition, sources (determined using Lagrangian backward trajectory calculations) and absorption properties between 2011 and 2012, (8) coincident ozone and dust surface area

  12. [Evaluation of bone mineral density using digital image processing in children receiving anticonvulsants].

    Science.gov (United States)

    Suzuki, Keiko; Ueda, Satoru; Umezu, Ryouji; Matsuoka, Hisafumi; Sugihara, Shigetaka

    2007-09-01

    Bone mineral density (BMD) increases rapidly in a biphasic manner in childhood. During and after adolescence, BMD correlates more closely with bone age than chronological age. Digital image processing (DIP) allows the rapid assessment of BMD and bone age on one X-ray film. Herein, using DIP methods, the effects of various anticonvulsants on chronological and bone age were evaluated in 98 epilepsy patients (age range, 3-15 years) with no intellectual or motor disorders or diseases affecting bone metabolism. All patients were taking one or a combination of the following anticonvulsants: valproate sodium (VPA); carbamazepine (CBZ); and phenobarbital (PB). Bone maturation scores for radius-ulnar-short bones (RUS) were calculated using Tanner-Whitehouse 2 methods. Bone age was determined based on standard Japanese bone-maturation scores. In each patient, Z-scores for chronological and bone ages were calculated by subtracting standard BMD for gender and age from each BMD, then dividing the result by the standard deviation. The Z-score for each drug in relation to the administration period was analyzed using the Mann-Whitney test. For chronological age, significant differences in BMD were observed regarding the administration periods in children taking multiple drugs, but not in children on VPA, CBZ, or PB monotherapy. For bone age, no significant differences in BMD were observed regarding the administration periods for all drugs. Children taking multiple drugs showed a significant negative correlation between administration period and Z-scores for BMD calculated based on chronological age (Spearman rank correlation: - 0.457, p = 0.008), but not bone age. Among children receiving long-term VPA administration, bone age was delayed approximately 1 year, and bone maturation may have been delayed. No delay in bone age was noted among children receiving long-term administration of multiple drugs, suggesting that these anticonvulsants do not influence bone maturity. These

  13. Aqueous mineral carbonation as a possible CO2 sequestration process. Energetic efficiency and costs. Carbon dioxide, sequestration, mineral carbonation, energy consumption, costs

    Energy Technology Data Exchange (ETDEWEB)

    Huijgen, W.J.J.; Ruijg, G.J.; Comans, R.N.J. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands); Witkamp, G.J. [Delft University of Technology, Delft (Netherlands)

    2006-04-15

    Aqueous mineral carbonation is a potentially attractive sequestration technology to reduce CO2 emissions. In this paper, the energy consumption and costs of this technology were assessed using either wollastonite (CaSiO3) or steel slag as feedstock. The major energy-consuming process steps were found to be the grinding of the feedstock and the compression of the CO2. Within ranges of experimentally investigated process conditions, optimum energetic CO2 sequestration efficiencies were 79 and 74% for wollastonite and steel slag, respectively. It was shown that the energetic performance for both feedstock might be improved up to >90% by e.g. further grinding of the feedstock and reducing the amount of process water applied. At energetically optimized process conditions, a preliminary cost estimate was made of 93 and 66 euro/ton CO2 avoided for wollastonite and steel slag, respectively (sequestration costs excluding possible capture). For wollastonite, major costs were associated with the feedstock and the electricity consumption (51 and 20 euro/ton CO2 avoided, respectively). A sensitivity analysis showed that additional influential parameters with regard to the sequestration costs include the liquid-to-solid ratio applied in the carbonation reactor and the possible commercial value of the carbonated product.

  14. Twenty lectures on thermodynamics

    CERN Document Server

    Buchdahl, H A

    2013-01-01

    Twenty Lectures on Thermodynamics is a course of lectures, parts of which the author has given various times over the last few years. The book gives the readers a bird's eye view of phenomenological and statistical thermodynamics. The book covers many areas in thermodynamics such as states and transition; adiabatic isolation; irreversibility; the first, second, third and Zeroth laws of thermodynamics; entropy and entropy law; the idea of the application of thermodynamics; pseudo-states; the quantum-static al canonical and grand canonical ensembles; and semi-classical gaseous systems. The text

  15. Advances in chemical and physical properties of electric arc furnace carbon steel slag by hot stage processing and mineral mixing.

    Science.gov (United States)

    Liapis, Ioannis; Papayianni, Ioanna

    2015-01-01

    Slags are recognised as a highly efficient, cost effective tool in the metal processing industry, by minimising heat losses, reducing metal oxidation through contact with air, removing metal impurities and protecting refractories and graphite electrodes. When compared to natural aggregates for use in the construction industry, slags have higher specific weight that acts as an economic deterrent. A method of altering the specific weight of EAFC slag by hot stage processing and mineral mixing, during steel production is presented in this article. The method has minimal interference with the production process of steel, even by limited additions of appropriate minerals at high temperatures. Five minerals are examined, namely perlite, ladle furnace slag, bauxite, diatomite and olivine. Measurements of specific weight are accompanied by X-ray diffraction (XRD) and fluorescence (XRF) analysis and scanning electron microscopy spectral images. It is also shown how altering the chemical composition is expected to affect the furnace refractory lining. Additionally, the process has been repeated for the most suitable mix in gas furnace and physical properties (FI, SI, LA, PSV, AAV, volume stability) examined. Alteration of the specific weight can result in tailoring slag properties for specific applications in the construction sector.

  16. PETROMAP: MS-DOS software package for quantitative processing of X-ray maps of zoned minerals

    Science.gov (United States)

    Cossio, Roberto; Borghi, Alessandro

    1998-10-01

    This paper shows an application of energy dispersive spectrometry (EDS) for digital acquisition of multi-element X-ray compositional maps of minerals in polished thin sections. A square matrix of n EDS spectra with known X, Y coordinates is collected, converted and exported to a personal computer. Each spectrum of the matrix is processed and the apparent concentration of each analyzed element is calculated by means of PETROMAP, a program written in Quick-Basic which applies a quantitative ZAF/FLS correction. The results of processing are comparable to the conventional quantitative microprobe analyses, with similar counting statistics. The output is a numerical matrix, compatible with the most popular graphic and spreadsheet programs from which it is possible to produce two-dimensional wt% oxide, mole fractions and mineral end-members pseudocolored or black/white maps. The procedure has been tested using a metamorphic garnet of the medium-grade Stilo unit (Calabrian Arc, Southern Italy).

  17. How different is mining from mineral processing? A general equilibrium analysis of new resources projects in Western Australia

    OpenAIRE

    Qiang, Ye

    1999-01-01

    Western Australia has experienced an investment surge in the minerals sector of the economy in recent years. Unlike previous surges, this one involves a large proportion of mineral‐processing projects. In this study, the differential effects on the WA economy of 25 mining and 10 mineral‐processing projects are analysed using an economy‐wide model of WA. The results indicate that: (i) both the mining and mineral‐processing projects will have substantial flow‐on benefits to the WA economy as a ...

  18. Improved and new uses of natural radioactivity in mineral exploration and processing

    NARCIS (Netherlands)

    de Meijer, R.J.; Stapel, C.; Jones, D.G.; Roberts, P.D.; Rozendaal, A.; Macdonald, W.G.

    1997-01-01

    Measurement of natural radioactivity has been used in both a qualitative and a quantitative way in mineral exploration, particularly in the search for uranium. In the last five years, the Kernfysisch Versneller Instituut (KVI) and British Geological Survey (BGS) have designed, built and tested a new

  19. Fractionation and fluxes of metals and radionuclides during the recycling process of phosphogypsum wastes applied to mineral CO2 sequestration

    OpenAIRE

    Contreras Llanes, Manuel; Pérez López, Rafael; Gázquez González, Manuel Jesús; Morales Flórez, V.; Santos, A; Esquivias, L.; Bolívar Raya, Juan Pedro

    2015-01-01

    The industry of phosphoric acid produces a calcium-rich by-product known as phosphogypsum, which is usually stored in large stacks of millions of tons. Up to now, no commercial application has been widely implemented for its reuse because of the significant presence of potentially toxic contaminants. This work confirmed that up to 96% of the calcium of phosphogypsum could be recycled for CO2 mineral sequestration by a simple two-step process: alkaline dissolution and aqueous carbonation, unde...

  20. Reaction process of monazite and bastnaesite mixed rare earth minerals calcined by CaO-NaCl-CaCl2

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The decomposition reactions of monazite and bastnaesite mixed rare earth minerals calcined by CaO-NaCl-CaCl2 were studied by means of TG-DTA and XRD. The results show that the process of the minerals decomposed by CaO involves two steps.The first step occurs in the temperature range of 425-540 ℃, and the main reactions are bastnaesite decomposition, i.e. REOF reacts with CaO to produce RE2O3 and CaF2, and Ce2O3 is oxidized to CeO2. During this step, CaCO3 is formed at about 500 ℃. The second step takes place in the temperature range of 610-700 ℃, and the reactions are monazite decomposition into RE2O3,Ca5F(PO4)3 and Ca3(PO4)2 by CaO and CaF2. In this process, the decomposition ability is improved because CaO from CaCO3decomposing has high chemical activity. In calcining process, the new formed Ca5F(PO4)3 restrains fluorine that can escape in form of gaseous compound. The decomposition ratio of the mixed rare earth minerals reaches 90.8% at 700 ℃.

  1. Twenty Years of KSHV

    Directory of Open Access Journals (Sweden)

    Yuan Chang

    2014-11-01

    Full Text Available Twenty years ago, Kaposi’s sarcoma (KS was the oncologic counterpart to Winston Churchill’s Russia: a riddle, wrapped in a mystery, inside an enigma. First described by Moritz Kaposi in 1872, who reported it to be an aggressive skin tumor, KS became known over the next century as a slow-growing tumor of elderly men—in fact, most KS patients were expected to die with the tumor rather than from it. Nevertheless, the course and manifestations of the disease varied widely in different clinical contexts. The puzzle of KS came to the forefront as a harbinger of the AIDS epidemic. The articles in this issue of Viruses recount progress made in understanding Kaposi’s sarcoma herpesvirus (KSHV since its initial description in 1994.

  2. Process-based modeling of silicate mineral weathering responses to increasing atmospheric CO2 and climate change

    Science.gov (United States)

    Banwart, Steven A.; Berg, Astrid; Beerling, David J.

    2009-12-01

    A mathematical model describes silicate mineral weathering processes in modern soils located in the boreal coniferous region of northern Europe. The process model results demonstrate a stabilizing biological feedback mechanism between atmospheric CO2 levels and silicate weathering rates as is generally postulated for atmospheric evolution. The process model feedback response agrees within a factor of 2 of that calculated by a weathering feedback function of the type generally employed in global geochemical carbon cycle models of the Earth's Phanerozoic CO2 history. Sensitivity analysis of parameter values in the process model provides insight into the key mechanisms that influence the strength of the biological feedback to weathering. First, the process model accounts for the alkalinity released by weathering, whereby its acceleration stabilizes pH at values that are higher than expected. Although the process model yields faster weathering with increasing temperature, because of activation energy effects on mineral dissolution kinetics at warmer temperature, the mineral dissolution rate laws utilized in the process model also result in lower dissolution rates at higher pH values. Hence, as dissolution rates increase under warmer conditions, more alkalinity is released by the weathering reaction, helping maintain higher pH values thus stabilizing the weathering rate. Second, the process model yields a relatively low sensitivity of soil pH to increasing plant productivity. This is due to more rapid decomposition of dissolved organic carbon (DOC) under warmer conditions. Because DOC fluxes strongly influence the soil water proton balance and pH, this increased decomposition rate dampens the feedback between productivity and weathering. The process model is most sensitive to parameters reflecting soil structure; depth, porosity, and water content. This suggests that the role of biota to influence these characteristics of the weathering profile is as important, if not

  3. The interaction of mineral nutrition and water supply in the process of winter wheat production

    Directory of Open Access Journals (Sweden)

    J. Šhivra

    2013-12-01

    Full Text Available In pot experiments performed in 1972-1976 with winter wheat variety 'Ilyichovka' grown at three levels of increasing mineral nutrition and at different levels of water supply (70% and 40% of maximal water capacity an interaction was observed between mineral nutrition and water availability on the yield and some physiological characteristics of the plants. Water stress during heading stage reduced nearly by one half the grain yield per plant, mostly by decreasing the number of completely filled grains. The quicker leaf senescence and grain number reduction as well as the total grain yield due to water stress differed between the nutritional levels. The relations between leaf surface area and grain yields were nearly linear in treatments with optimal water supply, but were markedly changed by water stress.

  4. Surface modification of mineral dust particles by sulphuric acid processing: implications for CCN and IN abilities

    OpenAIRE

    P. Reitz; C. Spindler; T. F. Mentel; Poulain, L.; H. Wex; K. Mildenberger; D. Niedermeier; Hartmann, S.; T. Clauss; F. Stratmann; R. C. Sullivan; Demott, P. J.; Petters, M. D.; Sierau, B.; Schneider, J.

    2011-01-01

    The ability of coated mineral dust particles to act as cloud condensation nuclei (CCN) and ice nuclei (IN) was investigated at LACIS (Leipzig Aerosol Cloud Interaction Simulator) during the FROST1- and FROST2-campaigns (Freezing of dust). Sulphuric acid was condensed on the particles which afterwards were optionally humidified, treated with ammonia vapour and/or heat. By means of aerosol mass spectrometry we found evidence that processi...

  5. Mathematical model formation of the process of deriving boric acid from ulexite mineral by full factorial design method

    OpenAIRE

    DURAK, Halil; GENEL, Yasar; BASHIROV, Novruz; KERIMOV, Genber

    2012-01-01

    Ulexite is a sodium calcium boron hydrate used in producing compounds, its chemical formula is Na2O2CaO5B2O3.16H2O, and it superabounds in Turkey. One of the significant boron compounds derived from boron minerals is boric acid. The aim of this study is producing boric acid in the wake of interaction of ulexite with hydrochloric acid solution, and offering an alternative process to producing boric acid by forming the mathematical model of this processing. F...

  6. Mathematical model formation of the process of deriving boric acid from ulexite mineral by full factorial design method

    OpenAIRE

    DURAK, Halil; GENEL, Yasar; BASHIROV, Novruz; KERIMOV, Genber

    2013-01-01

    Ulexite is a sodium calcium boron hydrate used in producing compounds, its chemical formula is Na2O2CaO5B2O3.16H2O, and it superabounds in Turkey. One of the significant boron compounds derived from boron minerals is boric acid. The aim of this study is producing boric acid in the wake of interaction of ulexite with hydrochloric acid solution, and offering an alternative process to producing boric acid by forming the mathematical model of this processing. Full factorial de...

  7. Residence time, mineralization processes and groundwater origin within a carbonate coastal aquifer with a thick unsaturated zone

    Science.gov (United States)

    Santoni, S.; Huneau, F.; Garel, E.; Vergnaud-Ayraud, V.; Labasque, T.; Aquilina, L.; Jaunat, J.; Celle-Jeanton, H.

    2016-09-01

    This study aims at establishing groundwater residence times, identifying mineralization processes and determining groundwater origins within a carbonate coastal aquifer with thick unsaturated zone and lying on a granitic depression. A multi-tracer approach (major ions, SiO2, Br-, Ba+, Sr2+, 18O, 2H, 13C, 3H, Ne, Ar) combined with a groundwater residence time determination using CFCs and SF6 allows defining the global setting of the study site. A typical mineralization conditioned by the sea sprays and the carbonate matrix helped to validate the groundwater weighted residence times from using a binary mixing model. Terrigenic SF6 excesses have been detected and quantified, which permits to identify a groundwater flow from the surrounding fractured granites towards the lower aquifer principally. The use of CFCs and SF6 as a first hydrogeological investigation tool is possible and very relevant despite the thick unsaturated zone and the hydraulic connexion with a granitic environment.

  8. Optimization of the mineralization of a mixture of phenolic pollutants under a ferrioxalate-induced solar photo-Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Monteagudo, J.M., E-mail: josemaria.monteagudo@uclm.es [University of Castilla-La Mancha, Grupo IMAES, Department of Chemical Engineering, Escuela Tecnica Superior de Ingenieros Industriales, Avda. Camilo Jose Cela, 1, 13071 Ciudad Real (Spain); Duran, A.; Aguirre, M.; San Martin, I. [University of Castilla-La Mancha, Grupo IMAES, Department of Chemical Engineering, Escuela Tecnica Superior de Ingenieros Industriales, Avda. Camilo Jose Cela, 1, 13071 Ciudad Real (Spain)

    2011-01-15

    The mineralization of solutions containing a mixture of three phenolic compounds, gallic, p-coumaric and protocatechuic acids, in a ferrioxalate-induced solar photo-Fenton process was investigated. The reactions were carried out in a pilot plant consisting of a compound parabolic collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and neuronal networks that included the following variables: pH, temperature, solar power, air flow and initial concentrations of H{sub 2}O{sub 2}, Fe(II) and oxalic acid. Under optimal conditions, total elimination of the original compounds and 94% TOC removal of the mixture were achieved in 5 and 194 min, respectively. pH and initial concentrations of H{sub 2}O{sub 2} and Fe(II) were the most significant factors affecting the mixture mineralization. The molar correlation between consumed hydrogen peroxide and removed TOC was always between 1 and 3. A detailed analysis of the reaction was presented. The values of the pseudo-first-order mineralization kinetic rate constant, k{sub TOC}, increased as initial Fe(II) and H{sub 2}O{sub 2} concentrations and temperature increased. The optimum pH value also slightly increased with greater Fe(II) and hydrogen peroxide concentrations but decreased when temperature increased. {center_dot}OH and O{sub 2}{center_dot}{sup -} radicals were the main oxidative intermediate species in the process, although singlet oxygen ({sup 1}O{sub 2}) also played a role in the mineralization reaction.

  9. Atmospheric transport of mineral dust from the Indo-Gangetic Plain: Temporal variability, acid processing, and iron solubility

    Science.gov (United States)

    Srinivas, Bikkina; Sarin, M. M.; Rengarajan, R.

    2014-08-01

    transport of chemical constituents from the Indo-Gangetic Plain (IGP) to the Bay of Bengal is a conspicuous seasonal feature that occurs during the late NE-monsoon (December-March). With this perspective, aerosol composition and abundance of mineral dust have been studied during November 2009 to March 2010 from a sampling site (Kharagpur: 22.3°N, 87.3°E) in the IGP, representing the atmospheric outflow to the Bay of Bengal. The chemical composition of PM2.5 suggests the dominance of nss-SO42- (6.9-24.3 µg m-3); whereas the abundance of mineral dust varied from 3 to 18 µg m-3. The concentration of aerosol iron (FeTot) and its fractional solubility (Fews % = Fews/FeTot *100, where Fews is the water-soluble fraction of FeTot) varied from 60 to 1144 ng m-3 and from 6.7 to 26.5%, respectively. A striking similarity in the temporal variability of total inorganic acidity (TIA = NO3- + nss-SO42-) and Fews (%) provides evidence for acid processing of mineral dust (alluvium) during atmospheric transport from the IGP. The contribution of TIA to water-soluble inorganic species [(nss-SO42- + NO3-)/ΣWSIS], mass ratios of Ca/Al and Fe/Al, and abundance of dust (%) and Fews (%) in the IGP-outflow are similar to the aerosol composition over the Bay of Bengal. With the rapid increase in anthropogenic activities over south and south-east Asia, the enhanced fractional solubility of aerosol iron (attributed to acid processing of mineral dust) has implications to further increase in the air-sea deposition of Fe to the Ocean surface.

  10. Determinants of pathologic mineralization.

    Science.gov (United States)

    Kirsch, Thorsten

    2008-01-01

    Physiologic mineralization is necessary for the formation of skeletal tissues and for their appropriate functions during adulthood. Mineralization has to be controlled and restricted to specific regions. If the mineralization process occurs in regions that normally do not mineralize, there can be severe consequences (pathologic or ectopic mineralization). Recent findings have indicated that physiologic and pathologic mineralization events are initiated by matrix vesicles, membrane-enclosed particles released from the plasma membranes of mineralization-competent cells. The understanding of how these vesicles are released from the plasma membrane and initiate the mineralization process may provide novel therapeutic strategies to prevent pathologic mineralization. In addition, other regulators (activators and inhibitors) of physiologic mineralization have been identified and characterized, and there is evidence that the same factors also contribute to the regulation of pathologic mineralization. Finally, programmed cell death (apoptosis) may be a contributor to physiologic mineralization and if occurring after tissue injury may induce pathologic mineralization and mineralization-related differentiation events in the injured and surrounding areas. This review describes how the understanding of mechanisms and factors regulating physiologic mineralization can be used to develop new therapeutic strategies to prevent pathologic or ectopic mineralization events.

  11. Conflict minerals from the Democratic Republic of the Congo: global tungsten processing plants, a critical part of the tungsten supply chain

    Science.gov (United States)

    Bermúdez-Lugo, Omayra

    2014-01-01

    The U.S. Geological Survey (USGS) analyzes supply chains to identify and define major components of mineral and material flows from ore extraction, through intermediate forms, to a final product. Two major reasons necessitate these analyses: (1) to identify risks associated with the supply of critical and strategic minerals to the United States and (2) to provide greater supply chain transparency so that policymakers have the information necessary to ensure domestic legislation compliance. This fact sheet focuses on the latter. The USGS National Minerals Information Center has been asked by governmental and non-governmental organizations to provide information on tin, tantalum, tungsten, and gold (collectively known as “3TG minerals”) processing facilities worldwide in response to U.S. legislation aimed at removing the link between the trade in these minerals and civil unrest in the Democratic Republic of the Congo. Post beneficiation processing plants (smelters and refineries) of 3TG mineral ores and concentrates were identified by company and industry association representatives as being the link in the 3TG mineral supply chain through which these minerals can be traced to their source of origin (mine); determining the point of origin is critical to establishing a transparent conflict mineral supply chain. This fact sheet, the first in a series of 3TG mineral fact sheets, focuses on the tungsten supply chain by listing plants that consume tungsten concentrates to produce ammonium paratungstate and ferrotungsten worldwide.

  12. Top at Twenty

    CERN Document Server

    2015-01-01

    The "Top at Twenty" workshop is dedicated to the celebration of 20 years since the top quark discovery at Fermilab in 1995. Speakers from all experiments capable of studying top quark, ATLAS, CDF, CMS and DZero, will present the most recent results of the top quark studies based on Run II of the Tevatron and Run I of the LHC. Reviews of such fundamental measurements as mass of the top quark, its spin, charge and production properties are planned with some of them orders of magnitude better in precision in comparison with original CDF and DZero papers announcing the top quark discovery. Measurements of top quark production and decay that illuminate the nature of the Higgs boson and seek new phenomena will be presented. Theoretical talks on how the top quark fits into the Standard Model and its potential extensions will also be presented. This workshop will complement the yearly Top Workshop which is held in September and will benefit from many new results expected to be presented at winter conferences in 2015...

  13. Sub-Saharan Northern African climate at the end of the twenty-first century: forcing factors and climate change processes

    Energy Technology Data Exchange (ETDEWEB)

    Patricola, C.M. [Cornell University, Department of Earth and Atmospheric Sciences, Ithaca, NY (United States); Texas A and M University, Department of Atmospheric Sciences, College Station, TX (United States); Cook, K.H. [The University of Texas at Austin, Department of Geological Sciences, Jackson School of Geosciences, Austin, TX (United States)

    2011-09-15

    A regional climate model, the Weather Research and Forecasting (WRF) Model, is forced with increased atmospheric CO{sub 2} and anomalous SSTs and lateral boundary conditions derived from nine coupled atmosphere-ocean general circulation models to produce an ensemble set of nine future climate simulations for northern Africa at the end of the twenty-first century. A well validated control simulation, agreement among ensemble members, and a physical understanding of the future climate change enhance confidence in the predictions. The regional model ensembles produce consistent precipitation projections over much of northern tropical Africa. A moisture budget analysis is used to identify the circulation changes that support future precipitation anomalies. The projected midsummer drought over the Guinean Coast region is related partly to weakened monsoon flow. Since the rainfall maximum demonstrates a southward bias in the control simulation in July-August, this may be indicative of future summer drying over the Sahel. Wetter conditions in late summer over the Sahel are associated with enhanced moisture transport by the West African westerly jet, a strengthening of the jet itself, and moisture transport from the Mediterranean. Severe drought in East Africa during August and September is accompanied by a weakened Indian monsoon and Somali jet. Simulations with projected and idealized SST forcing suggest that overall SST warming in part supports this regional model ensemble agreement, although changes in SST gradients are important over West Africa in spring and fall. Simulations which isolate the role of individual climate forcings suggest that the spatial distribution of the rainfall predictions is controlled by the anomalous SST and lateral boundary conditions, while CO{sub 2} forcing within the regional model domain plays an important secondary role and generally produces wetter conditions. (orig.)

  14. Advances in chemical and physical properties of electric arc furnace carbon steel slag by hot stage processing and mineral mixing

    Energy Technology Data Exchange (ETDEWEB)

    Liapis, Ioannis, E-mail: iliapis@sidenor.vionet.gr [AEIFOROS SA, 12th km Thessaloniki-Veroia Rd, PO Box 59, 57008 Ionia, Thessaloniki (Greece); Papayianni, Ioanna [Laboratory of Building Materials, Department of Civil Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2015-02-11

    Highlights: • Addition of 10% perlite decreases specific weight of the slag by approx. 7.5%. • Slag-crucible interaction and thin coating layer result in variations in XRF. • XRD shows high glass content and smaller crystalline sizes due to rapid cooling. • SEM shows higher homogeneity and lower crystallisation for SiO{sub 2}/CaO-rich samples. • Physical properties (LA, PSV, AAV) of modified slag show limited deterioration. - Abstract: Slags are recognised as a highly efficient, cost effective tool in the metal processing industry, by minimising heat losses, reducing metal oxidation through contact with air, removing metal impurities and protecting refractories and graphite electrodes. When compared to natural aggregates for use in the construction industry, slags have higher specific weight that acts as an economic deterrent. A method of altering the specific weight of EAFC slag by hot stage processing and mineral mixing, during steel production is presented in this article. The method has minimal interference with the production process of steel, even by limited additions of appropriate minerals at high temperatures. Five minerals are examined, namely perlite, ladle furnace slag, bauxite, diatomite and olivine. Measurements of specific weight are accompanied by X-ray diffraction (XRD) and fluorescence (XRF) analysis and scanning electron microscopy spectral images. It is also shown how altering the chemical composition is expected to affect the furnace refractory lining. Additionally, the process has been repeated for the most suitable mix in gas furnace and physical properties (FI, SI, LA, PSV, AAV, volume stability) examined. Alteration of the specific weight can result in tailoring slag properties for specific applications in the construction sector.

  15. Offline modeling for product quality prediction of mineral processing using modeling error PDF shaping and entropy minimization.

    Science.gov (United States)

    Ding, Jinliang; Chai, Tianyou; Wang, Hong

    2011-03-01

    This paper presents a novel offline modeling for product quality prediction of mineral processing which consists of a number of unit processes in series. The prediction of the product quality of the whole mineral process (i.e., the mixed concentrate grade) plays an important role and the establishment of its predictive model is a key issue for the plantwide optimization. For this purpose, a hybrid modeling approach of the mixed concentrate grade prediction is proposed, which consists of a linear model and a nonlinear model. The least-squares support vector machine is adopted to establish the nonlinear model. The inputs of the predictive model are the performance indices of each unit process, while the output is the mixed concentrate grade. In this paper, the model parameter selection is transformed into the shape control of the probability density function (PDF) of the modeling error. In this context, both the PDF-control-based and minimum-entropy-based model parameter selection approaches are proposed. Indeed, this is the first time that the PDF shape control idea is used to deal with system modeling, where the key idea is to turn model parameters so that either the modeling error PDF is controlled to follow a target PDF or the modeling error entropy is minimized. The experimental results using the real plant data and the comparison of the two approaches are discussed. The results show the effectiveness of the proposed approaches.

  16. In situ Raman characterization of minerals and degradation processes in a variety of cultural and geological heritage sites

    Science.gov (United States)

    Gázquez, F.; Rull, F.; Sanz-Arranz, A.; Medina, J.; Calaforra, J. M.; de las Heras, C.; Lasheras, J. A.

    2017-02-01

    We test the capabilities of in situ Raman spectroscopy for non-destructive analysis of degradation processes in invaluable masterpieces, as well as for the characterization of minerals and prehistoric rock-art in caves. To this end, we have studied the mechanism of decay suffered by the 15th-century limestone sculptures that decorate the retro-choir of Burgos Cathedral (N Spain). In situ Raman probe detected hydrated sulfate and nitrate minerals on the sculptures, which are responsible for the decay of the original limestone. In addition, in situ Raman analyses were performed on unique speleothems in El Soplao Cave (Cantabria, N Spain) and in the Gruta de las Maravillas (Aracena, SW Spain). Unusual cave minerals were detected in El Soplao Cave, such as hydromagnesite (Mg5(CO3)4(OH)2·4H2O), as well as ferromanganese oxides in the black biogenic speleothems recently discovered in this cavern. In the Gruta de las Maravillas, gypsum (CaSO4·2H2O) was identified for the first time, as part of the oldest cave materials, so providing additional evidence of hypogenic mechanisms that occurred in this cave during earlier stages of its formation. Finally, we present preliminary analyses of several cave paintings in the renowned "Polychrome Hall" of Altamira Cave (Cantabria, N. Spain). Hematite (Fe2O3) is the most abundant mineral phase, which provides the characteristic ochre-reddish color to the Altamira bison and deer paintings. Thus, portable Raman spectroscopy is demonstrated to be an analytical technique compatible with preserving our cultural and natural heritage, since the analysis does not require physical contact between the Raman head and the analyzed items.

  17. In situ Raman characterization of minerals and degradation processes in a variety of cultural and geological heritage sites.

    Science.gov (United States)

    Gázquez, F; Rull, F; Sanz-Arranz, A; Medina, J; Calaforra, J M; de Las Heras, C; Lasheras, J A

    2017-02-05

    We test the capabilities of in situ Raman spectroscopy for non-destructive analysis of degradation processes in invaluable masterpieces, as well as for the characterization of minerals and prehistoric rock-art in caves. To this end, we have studied the mechanism of decay suffered by the 15th-century limestone sculptures that decorate the retro-choir of Burgos Cathedral (N Spain). In situ Raman probe detected hydrated sulfate and nitrate minerals on the sculptures, which are responsible for the decay of the original limestone. In addition, in situ Raman analyses were performed on unique speleothems in El Soplao Cave (Cantabria, N Spain) and in the Gruta de las Maravillas (Aracena, SW Spain). Unusual cave minerals were detected in El Soplao Cave, such as hydromagnesite (Mg5(CO3)4(OH)2·4H2O), as well as ferromanganese oxides in the black biogenic speleothems recently discovered in this cavern. In the Gruta de las Maravillas, gypsum (CaSO4·2H2O) was identified for the first time, as part of the oldest cave materials, so providing additional evidence of hypogenic mechanisms that occurred in this cave during earlier stages of its formation. Finally, we present preliminary analyses of several cave paintings in the renowned "Polychrome Hall" of Altamira Cave (Cantabria, N. Spain). Hematite (Fe2O3) is the most abundant mineral phase, which provides the characteristic ochre-reddish color to the Altamira bison and deer paintings. Thus, portable Raman spectroscopy is demonstrated to be an analytical technique compatible with preserving our cultural and natural heritage, since the analysis does not require physical contact between the Raman head and the analyzed items. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Mineralization of the connective tissue: a complex molecular process leading to age-related loss of function.

    Science.gov (United States)

    Shindyapina, Anastasia V; Mkrtchyan, Garik V; Gneteeva, Tatiana; Buiucli, Sveatoslav; Tancowny, B; Kulka, M; Aliper, Alexander; Zhavoronkov, Alexander

    2014-04-01

    Age-related metastatic mineralization of soft tissues has been considered a passive and spontaneous process. Recent data have demonstrated that calcium salt deposition in soft tissues could be a highly regulated process. Although calcification occurs in any tissue type, vascular calcification has been of particular interest due to association with atherosclerosis, chronic kidney disease (CKD), and osteoporosis. Different mechanisms underlying calcium apatite accumulation are explored with these age-related disorders. In the case of atherosclerotic plaques, oxy-lipids trigger release of the pro-inflammatory cytokines and inflammation that activate calcification processes in aorta intimae. In CKD patients, renal failure alters the balance between calcium and phosphate levels usually regulated by fibroblast growth factor-23 (FGF23), Klotho, and vitamin D, and vascular smooth muscle cells (VSMCs) begin to explore an osteoblastosteoblast-like phenotype. Calcification could affect extracellular matrix along with VSMCs. Collagen is a major component of extracellular matrix and its modifications accumulate with age. The formation of cross-links between collagen fibers is regulated by the action of lysine hydroxylases and lysyl oxidase and could occur spontaneously. Oxidation-induced advanced glycation end products (AGEs) are a major type of spontaneous cross-links that accelerate with age and may result in tissue stiffness, problems with recycling, and potential accumulation of calcium apatite. Applying strategies for clearing the AGEs proposed by de Grey may be more difficult in the highly mineralized extracellular matrix. We performed bioinformatic analysis of the molecular pathways underlying calcification in atherosclerotic and CKD patients, signaling pathways of collagen cross-links formation, and bone mineralization, and we propose new potential targets and review drugs for calcification treatment.

  19. Enforcement Alert: Hazardous Waste Management Practices at Mineral Processing Facilities Under Scrutiny by U.S. EPA; EPA Clarifies 'Bevill Exclusion' Wastes and Establishes Disposal Standards

    Science.gov (United States)

    This is the enforcement alert for Hazardous Waste Management Practices at Mineral Processing Facilities Under Scrutiny by U.S. EPA; EPA Clarifies 'Bevill Exclusion' Wastes and Establishes Disposal Standards

  20. Bubble size estimation using interfacial morphological information for mineral flotation process monitoring

    Institute of Scientific and Technical Information of China (English)

    YANG Chun-hua; XU Can-hui; MU Xue-min; ZHOU Kai-jun

    2009-01-01

    To relate froth structural information with mineral flotation performance, segmentation analysis was performed on froth images characterized by fully occupied convex bubbles with white spots effect. An improved valley edge detection method was proposed to extract structural features and overcome fake white spot edges seriously affecting the segmentation performance. After preprocessing, detection template was designed based on the local minimal intensity, and a binary image containing segmented boundaries was obtained by applying logical rules, thinning and filtering. Statistical features such as bubble size were estimated for control purpose. Experimental results demonstrate that the proposed method avoids over-segmentation or ill-segmentation caused by uneven illumination, and the industrial application reveals the reliability of bubble size estimation.

  1. Interface Induced Carbonate Mineralization: A Fundamental Geochemical Process Relevant to Carbon Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Teng, H. Henry [PI, The George Washington University; Xu, Huifang [Co-PI, University of Wisconsin-Madison

    2013-07-17

    We have approached the long-standing geochemical question why anhydrous high-Mg carbonate minerals (i.e., magnesite and dolomite) cannot be formed at ambient conditions from a new perspective by exploring the formation of MgCO{sub 3} and Mg{sub x}Ca{sub (1-x)}CO{sub 3} in non-aqueous solutions. Data collected from our experiments in this funding period suggest that a fundamental barrier, other than cation hydration, exists that prevents Mg{sup 2+} and CO{sub 3}{sup 2-} ions from forming long-range ordered structures. We propose that this barrier mainly stems from the lattice limitation on the spatial configuration of CO{sub 3} groups in magnesite crystals. On the other hand, the measured higher distribution coefficients of Mg between magnesian calcites formed in the absence and presence of water give us a first direct proof to support and quantify the cation hydration effect.

  2. Hydrothermal Alteration Zoning and Kinetic Process of Mineral-Water Interactions

    Institute of Scientific and Technical Information of China (English)

    张荣华; 胡书敏; 苏艳丰

    2002-01-01

    This study reports the kinetic experimental results of albite in water and in KCl solution at 22 MPa in the temperature range of 25 to 400(C. Kinetic experiments have been carried out in an open flow-through reaction system (packed bed reactor). Albite dissolution is always incongruent in water at most temperatures, but becomes congruent at 300(C (close to the critical point 374(C). At temperatures from 25 to 300(C, the incongruent dissolution of albite is reflected by the fact that sodium and aluminum are easily dissolved into water; from 300 to 400(C it is reflected by silicon being more easily dissolved in water than Al and Na. Maximum albite dissolution rates in the flow hydrothermal systems have been repeatedly observed at 300(C, independent of flow rates.The kinetic experiments of albite dissolution in a KCl aqueous solution (0.1 mol KCl) indicate that the dissolution rate of albite increases with increasing temperature. Maximum silicon release rates of albite have been observed at 400(C, while maximum aluminum release rates of albite at 374(C. The reaction rates of albite also depend on the potassium concentration in the aqueous solution.These results can be used to interpret the mechanism for forming hydrothermal alteration. The kinetic experiments of mineral-aqueous solutions interactions in the hydrothermal system from 25 to 400(C and at 22 MPa indicate that the formation of the feldspar-mica-kaolinite zoning occurring in some ore deposits may depend not only on the mineral stability but also on the kinetics of feldspar hydration, which is affected by the water property variation when crossing the critical point.

  3. Minerals Yearbook, volume I, Metals and Minerals

    Science.gov (United States)

    ,

    2017-01-01

    The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

  4. Mineral bioprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Torma, A.E.

    1993-05-01

    In the last 25 years, the introduction of biotechnological methods in hydrometallurgy has created new opportunities and challenges for the mineral processing industry. This was especially true for the production of metal values from mining wastes and low-and-complex-grade mineral resources, which were considered economically not amenable for processing by conventional extraction methods. Using bio-assisted heap, dump and in-situ leaching technologies, copper and uranium extractions gained their first industrial applications. The precious metal industries were the next to adopt the bio-preoxidation technique in the extraction of gold from refractory sulfide-bearing ores and concentrates. A variety of other bioleaching opportunities exist for nickel, cobalt, cadmium and zinc sulfide leaching. Recently developed bioremediation methods and biosorption technologies have shown a good potential for industrial applications to remove trace heavy metal and radionuclide concentrations from contaminated soils, and mining and processing effluents.

  5. Burial diagenetic processes of clay mineral and non-clay mineral, quartz cementation and dissolution in sandstones and mudstones of the Siri Canyon, Danish North Sea

    DEFF Research Database (Denmark)

    Kazerouni, Afsoon Moatari; Friis, Henrik; Svendsen, Johan Byskov

    reprecipitate as opal, quartz or other mineral phases inside the shale itself. The deep marine sandstones in the Siri Canyon, Danish North Sea, have been reported to import significant amounts of dissolve silica from adjacent Paleocene shales during early diagenesis, and the authigenesis of silica developed...

  6. Outlook: The Next Twenty Years

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, Hitoshi

    2003-12-07

    I present an outlook for the next twenty years in particle physics. I start with the big questions in our field, broken down into four categories: horizontal, vertical, heaven, and hell. Then I discuss how we attack the bigquestions in each category during the next twenty years. I argue for a synergy between many different approaches taken in our field.

  7. Biogenic catalysis in sulphide minerals' weathering processes and acid mine drainage genesis.

    Science.gov (United States)

    Kušnierová, Mária; Praščáková, Mária; Nowak, Anna K; Gorazda, Katarzyna; Wzorek, Zbigniew

    2014-01-01

    Bioleaching and biogenesis are the main outputs from a large group of environmental processes participating in the natural material cycle, used in raw materials processing. Bio-oxidation reactions are the main basis for bioleaching procedures, often participating in parallel leaching processes. During the leaching processes of polycomponent sulphide substrates, the factor of process selection also plays an important role, being in direct relation to the electric properties and galvanic effect occurring between the individual components of the leaching substrate. This work gives a summary of the results of a research focused on the possibilities of using biotechnological procedures for treatment of Slovak sulphide ores. The object of the research is extraction of valuable metals, undesirable admixtures and degradation of crystal lattice of sulphides for subsequent chemical leaching processing of precious metals. The results of experiments on the existence of biogenic processes in situ on waste dumps from exploitation containing residual sulphides are also presented. The processes result in acid mine drainage water generation. These waters are strongly mineralised (over 48 g/L) and of low pH; that is why they are very caustic. The arsenic content (2.558 mg/L) in outflowing waters from old mines is high and over the limits set by the law.

  8. [Twenty-year History and Future Challenges in Transparency Enhancement of Review Process for Approval: Focus on Public Release of Review Reports regarding New Drugs and Medical Devices].

    Science.gov (United States)

    Morimoto, Kazushige; Kawasaki, Satoko; Yoshida, Yasunori

    2015-01-01

    For 20 years, the Ministry of Health, Labour and Welfare (MHLW, formerly Ministry of Health and Welfare (MHW)) has been trying to increase transparency of the review process for approving reports in order to promote the rational use of newly approved drugs and medical devices. The first Summary Basis of Approval (SBA) was published by MHW in 1994. In 1999, evaluation reports were prepared by MHW and the Pharmaceuticals and Medical Devices Evaluation Center to make them available to the public. In 2005, a notice from the Chief Executive of the Pharmaceuticals and Medical Devices Agency (PMDA) made procedures for public release of information on reviewing applications for new drugs. In 2006, 90 review reports of newly approved drugs and eight medical devices were revealed on PMDA websites. The dissemination of information by the United States Food and Drug Administration (FDA) and that of the European Medicines Agency (EMA) were studied and compared with that of the MHLW and PMDA. While common technical documents (CTD) for new drugs and summary technical documents (STED) for new medical devices have been released by PMDA, such documents are not released by the FDA and EMA. The European Public Assessment Report (EAPR) summary for the public is an interesting questionnaire approach that uses the "What," "How" and "Why" format. Finally, future proposals for the next decade are also outlined.

  9. Abiotic process for Fe(II) oxidation and green rust mineralization driven by a heterotrophic nitrate reducing bacteria (Klebsiella mobilis).

    Science.gov (United States)

    Etique, Marjorie; Jorand, Frédéric P A; Zegeye, Asfaw; Grégoire, Brian; Despas, Christelle; Ruby, Christian

    2014-04-01

    Green rusts (GRs) are mixed Fe(II)-Fe(III) hydroxides with a high reactivity toward organic and inorganic pollutants. GRs can be produced from ferric reducing or ferrous oxidizing bacterial activities. In this study, we investigated the capability of Klebsiella mobilis to produce iron minerals in the presence of nitrate and ferrous iron. This bacterium is well-known to reduce nitrate using an organic carbon source as electron donor but is unable to enzymatically oxidize Fe(II) species. During incubation, GR formation occurred as a secondary iron mineral precipitating on cell surfaces, resulting from Fe(II) oxidation by nitrite produced via bacterial respiration of nitrate. For the first time, we demonstrate GR formation by indirect microbial oxidation of Fe(II) (i.e., a combination of biotic/abiotic processes). These results therefore suggest that nitrate-reducing bacteria can potentially contribute to the formation of GR in natural environments. In addition, the chemical reduction of nitrite to ammonium by GR is observed, which gradually turns the GR into the end-product goethite. The nitrogen mass-balance clearly demonstrates that the total amount of ammonium produced corresponds to the quantity of bioreduced nitrate. These findings demonstrate how the activity of nitrate-reducing bacteria in ferrous environments may provide a direct link between the biogeochemical cycles of nitrogen and iron.

  10. A combination of biochar-mineral complexes and compost improves soil bacterial processes, soil quality and plant properties

    Directory of Open Access Journals (Sweden)

    JUN eYE

    2016-04-01

    Full Text Available Organic farming avoids the use of synthetic fertilizers and promises food production with minimal environmental impact, however this farming practice does not often result in the same productivity as conventional farming. In recent years, biochar has received increasing attention as an agricultural amendment and by coating it with minerals to form biochar-mineral complex (BMC carbon retention and nutrient availability can be improved. However, little is known about the potential of BMC in improving organic farming. We therefore investigated here how soil, bacterial and plant properties respond to a combined treatment of BMC and an organic fertilizer, i.e. a compost based on poultry manure. In a pakchoi pot trial, BMC and compost showed synergistic effects on soil properties, and specifically by increasing nitrate content. Soil nitrate has been previously observed to increase leaf size and we correspondingly saw an increase in the surface area of pakchoi leaves under the combined treatment of BMC and chicken manure. The increase in soil nitrate was also correlated with an enrichment of bacterial nitrifiers due to BMC. Additionally, we observed that the bacteria present in the compost treatment had a high turnover, which likely facilitated organic matter degradation and a reduction of potential pathogens derived from the manure. Overall our results demonstrate that a combination of BMC and compost can stimulate microbial process in organic farming that result in better vegetable production and improved soil properties for sustainable farming.

  11. Mineral elements, lipoxygenase activity, and antioxidant capacity of okara as a byproduct in hydrothermal processing of soy milk.

    Science.gov (United States)

    Stanojevic, Sladjana P; Barac, Miroljub B; Pesic, Mirjana B; Zilic, Sladjana M; Kresovic, Mirjana M; Vucelic-Radovic, Biljana V

    2014-09-10

    Minerals and antioxidative capacity of raw okara that was obtained as a byproduct from six soybean varieties during hydrothermal cooking (HTC) of soy milk were assessed. Lipoxygenase (Lox), an enzyme deteriorating the sensory characteristics of okara, was also investigated. All genotypes had very similar concentrations of Lox (4.32-5.62%). Compared to raw soybeans, the applied HTC significantly reduced Lox content in okara (0.54-0.19%) and lowered its activity to 0.004-0.007 μmol g(-1) min (-1). Correlation between the content of Lox in soybeans and that in okara (r = 0.21;p process than on soybean genotype. Very strong correlation (r = 0.99; p minerals in raw okara were potassium (1.04-1.21 g/100g), phosphorus (0.45-0.50 g/100 g), calcium (0.26-0.39 g/100 g), and iron (5.45-10.95 mg/100 g). A very high antioxidant capacity (19.06-29.36 mmol Trolox kg(-1)) contributes to the nutritional value of raw okara.

  12. Environmental consequences of processing manure to produce mineral fertilizer and bio-energy

    NARCIS (Netherlands)

    Vries, de J.W.; Groenestein, C.M.; Boer, de I.J.M.

    2012-01-01

    Liquid animal manure and its management contributes to environmental problems such as, global warming, acidification, and eutrophication. To address these environmental issues and their related costs manure processing technologies were developed. The objective here was to assess the environmental co

  13. Iron dissolution kinetics of mineral dust at low pH during simulated atmospheric processing

    Directory of Open Access Journals (Sweden)

    Z. Shi

    2011-02-01

    Full Text Available We investigated the iron (Fe dissolution kinetics of African (Tibesti and Asian (Beijing dust samples at acidic pH with the aim of reproducing the low pH conditions in atmospheric aerosols. The Beijing dust and three size fractions of the Tibesti dust (<20 μm: PM20; <10 μm: PM10; and <2.5 μm: PM2.5 were dissolved at pH 1, 2 and/or 3 for up to 1000 h. In the first 10 min, all dust samples underwent an extremely fast Fe solubilisation. Subsequently, the Fe dissolution proceeded at a much slower rate before reaching a stable dissolution plateau. The time-dependant Fe dissolution datasets were best described by a model comprising three acid-extractable Fe pools each dissolving according to first-order kinetics. The dissolution rate constant k (h−1 of each pool was independent of the source (Saharan or Asian and the size (PM20, PM10 or PM2.5 of the dust but highly dependent on pH. The "fast" Fe pool had a k (25 h−1 at pH = 1 of a similar magnitude to "dry" ferrihydrite nanoparticles and/or poorly crystalline Fe(III oxyhydroxide, while the "intermediate" and "slow" Fe pools had k values respectively 50–60 times and 3000–4000 times smaller than the "fast" pool. The "slow" Fe pool was likely to consist of both crystalline Fe oxide phases (i.e., goethite and/or hematite and Fe contained in the clay minerals. The initial mass of the "fast", "intermediate" and "slow" Fe pools represented respectively about 0.5–2%, 1–3% and 15–40% of the total Fe in the dust samples. Furthermore, we showed that in systems with low dust/liquid ratios, Fe can be dissolved from all three pools, whereas at high dust/liquid ratios (e.g., in aerosols, sufficient Fe may be solubilised from the "fast" phase to dominate the Fe dissolved and to suppress the dissolution of Fe from the other Fe pools. These data demonstrated that dust/liquid ratio and pH are

  14. Iron dissolution kinetics of mineral dust at low pH during simulated atmospheric processing

    Directory of Open Access Journals (Sweden)

    Z. Shi

    2010-11-01

    Full Text Available We investigated the iron (Fe dissolution kinetics of African (Tibesti and Asian (Beijing dust samples at acidic pH with the aim of reproducing the low pH conditions in atmospheric aerosols. The Beijing dust and three size fractions of the Tibesti dust (<20 μm: PM20; <10 μm: PM10; and <2.5 μm: PM2.5 were dissolved at pH 1, 2 and/or 3 for up to 1000 h. In the first 10 min, all dust samples underwent an extremely fast Fe solubilisation. Subsequently, the Fe dissolution proceeded at a much slower rate before reaching a stable dissolution plateau. The time-dependant Fe dissolution datasets were best described by a model comprising three acid-extractable Fe pools each dissolving according to first-order kinetics. The dissolution rate constant k of each pool was independent of the source (Saharan or Asian and the size (PM20, PM10 or PM2.5 of the dust but highly dependent on pH. The "fast" Fe pool had a k (25 h−1 at pH=1 of a similar magnitude to "dry" ferrihydrite nanoparticles and/or poorly crystalline Fe(III oxyhydroxide, while the "intermediate" and "slow" Fe pools had $k$ values respectively 50–60 times and 3000–4000 times smaller than the "fast" pool. The "slow" Fe pool was likely to consist of both crystalline Fe oxide phases (i.e., goethite and/or hematite and Fe contained in the clay minerals. The initial mass of the "fast", "intermediate" and "slow" Fe pools represented respectively about 0.5–2%, 1–3% and 15–40% of the total Fe in the dust samples. Furthermore, we showed that in systems with low dust/liquid ratios, Fe can be dissolved from all three phases, whereas at high dust/liquid ratios (e.g., in aerosols, sufficient Fe is solubilised from the "fast" phase to dominate the Fe dissolved and to suppress the dissolution of Fe from the other Fe pools. These data demonstrated that dust/liquid ratio and pH are fundamental parameters

  15. Carbon foam derived from pitches modified with mineral acids by a low pressure foaming process

    Energy Technology Data Exchange (ETDEWEB)

    Tsyntsarski, B.; Petrova, B.; Budinova, T.; Petrov, N.; Krzesinska, M.; Pusz, S.; Majewska, J.; Tzvetkov, P. [Bulgarian Academy of Science, Sofia (Bulgaria). Inst. of Organic Chemistry

    2010-10-15

    Carbon foams with an anisotropic texture and high mechanical strength were produced using precursors obtained after thermo-oxidation treatment of commercial coal-tar pitch with H{sub 2}SO{sub 4} and HNO{sub 3}. The investigations of the relation between the properties of the precursor and the structure of obtained foam indicate, that the composition and softening point of the pitch precursor significantly affect the foaming process, foam structure and foam mechanical strength. The composition and properties of the modified pitches allow foam formation at relatively low pressure and fast heating rate during the foaming process without a stabilization treatment. The foaming process of pitch-based carbon foams, pretreatment of the precursors, and the properties of resultant foams are discussed in this paper.

  16. Improved Disturbance Observer (DOB) Based Advanced Feedback Control for Optimal Operation of a Mineral Grinding Process%Improved Disturbance Observer (DOB) Based Advanced Feedback Control for Optimal Operation of a Mineral Grinding Process

    Institute of Scientific and Technical Information of China (English)

    周平; 向波; 柴天佑

    2012-01-01

    Advanced feedback control for optimal operation of mineral grinding process is usually based on the model predictive control (MPC) dynamic optimization. Since the MPC does not handle disturbances directly by controller design, it cannot achieve satisfactory effects in controlling complex grinding processes in the presence of strong disturbances and large uncertainties. In this paper, an improved disturbance observer (DOB) based MPC advanced feedback control is proposed to control the multivariable grinding operation. The improved DOB is based on the optimal achievable H 2 performance and can deal with disturbance observation for the nonminimum-phase delay systems. In this DOB-MPC advanced feedback control, the higher-level optimizer computes the optimal operation points by maximize the profit function and passes them to the MPC level. The MPC acts as a presetting controller and is employed to generate proper pre-setpoint for the lower-level basic feedback control system. The DOB acts as a compensator and improves the operation performance by dynamically compensating the setpoints for the basic control system according to the observed various disturbances and plant uncertainties. Several simulations are performed to demonstrate the proposed control method for grinding process operation.

  17. Effect of different debittering processes on mineral and phytic acid content of lupin (Lupinus albus L.) seeds.

    Science.gov (United States)

    Ertaş, Nilgün; Bilgiçli, Nermin

    2014-11-01

    Lupin is a valuable ancient legume which contains high amount of protein, dietary fiber, oil, minerals and different functional components. Bitter lupin seeds cannot be consumed directly since its high toxic alkaloid content. Cooking and soaking are effective processes for removing these toxic substances and antinutrients as phytic acid, trypsin inhibitors and oligosaccharides. In this study, debittering process containing cooking and soaking up to 144 h was applied to lupin seeds. Raw lupin seeds had 3.3 % ash and 41.3 % protein content. Ash and protein content of debittered seeds changed between 2.1 and 2.5 %, 39.5 and 40.9 % respectively. After debittering process, significant (p Phytic acid was removed from raw lupin seeds up to 71.4 % ratio by debittering processes, and soaking in distilled water at 55 °C and long soaking time (144 h) was found the most effective methods on phytic acid loss. While more lighter (L*) seeds were obtained with soaking in distilled water at 25 °C, soaking in 0.5 % NaHCO3 solution gave more yellowish (b*) seed properties compared to other soaking methods. Soaking in 0.5 % NaHCO3 solution at 144 h gave the most liked products in terms of sensorial evaluation.

  18. Oxidative mineralization and characterization of polyvinyl alcohol for compatibility with tank farm processing chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L.N.

    2000-01-04

    Polyvinyl alcohol (PVA) material has been evaluated for use as a cost-effective substitute for conventional cellulose-based disposal materials (decontamination mops and wipes), plastic bags, and disposable personal protection clothing, that are currently used at Savannah River Site. This study also provides process design criteria for ultraviolet/ultrasonic/hydrogen peroxide PVA reactor system.

  19. A coupled Bio-EF process for mineralization of the pharmaceuticals furosemide and ranitidine: Feasibility assessment.

    Science.gov (United States)

    Olvera-Vargas, Hugo; Oturan, Nihal; Buisson, Didier; Oturan, Mehmet A

    2016-07-01

    A coupled Bio-EF treatment has been applied as a reliable process for the degradation of the pharmaceuticals furosemide (FRSM) and ranitidine (RNTD) in aqueous medium, in order to reduce the high energy consumption related to electrochemical technology. In the first stage of this study, electrochemical degradation of the drugs was assessed by the electro-Fenton process (EF) using a BDD/carbon-felt cell. Biodegradability of the drugs solutions was enhanced reaching BOD5/COD ratios close to the biodegradability threshold of 0.4, evidencing the formation of bio-compatible by-products (mainly short-chain carboxylic acids) which are suitable for biological post-treatment. Moreover, toxicity evaluation by the Microtox(®) method revealed that EF pre-treatment was able of detoxifying both, FRSM and RNTD solutions, constituting another indicator of biodegradability of EF treated solutions. In the second stage, electrolyzed solutions were treated by means of an aerobic biological process. A significant part of the short-chain carboxylic acids formed during the electrochemical phase was satisfactorily removed by the used selected microorganisms. The results obtained demonstrate the efficiency and feasibility of the integrated Bio-EF process.

  20. Environmental Benign Process for Production of Molybdenum Metal from Sulphide Based Minerals

    Science.gov (United States)

    Rajput, Priyanka; Janakiram, Vangada; Jayasankar, Kalidoss; Angadi, Shivakumar; Bhoi, Bhagyadhar; Mukherjee, Partha Sarathi

    2017-02-01

    Molybdenum is a strategic and high temperature refractory metal which is not found in nature in free state, it is predominantly found in earth's crust in the form of MoO3/MoS2. The main disadvantage of the industrial treatment of Mo concentrate is that the process contains many stages and requires very high temperature. Almost in every step many gaseous, liquid, solid chemical substances are formed which require further treatment. To overcome the above drawback, a new alternative one step novel process is developed for the treatment of sulphide and trioxide molybdenum concentrates. This paper presents the results of the investigations on molybdenite dissociation (MoS2) using microwave assisted plasma unit as well as transferred arc thermal plasma torch. It is a single step process for the preparation of pure molybdenum metal from MoS2 by hydrogen reduction in thermal plasma. Process variable such as H2 gas, Ar gas, input current, voltage and time have been examined to prepare molybdenum metal. Molybdenum recovery of the order of 95% was achieved. The XRD results confirm the phases of molybdenum metal and the chemical analysis of the end product indicate the formation of metallic molybdenum (Mo 98%).

  1. Recovery process of the mineral sphalerite of Chaabet El Hamra’s deposit (Algeria

    Directory of Open Access Journals (Sweden)

    Djeghlal M.

    2012-06-01

    Full Text Available The present study rests on the treatment’s process optimization by flotation of the Chaabet El Hamra’s zinc ore (Algeria, for the optimization parameters relating to the production. The choice of parameter to optimize for flotation, and the arrangements and the scheme’s initial flotation, while considering the studies already undertaken, all this has enabled us to better focus our work, while minimizing the consumption of reagents in different tests, This has resulted in successful outcomes.

  2. Revisiting sulphide mineral (bio) processing:a few priorities and directions

    OpenAIRE

    Kota, Hanumantha Rao; Javadi, Alireza; Karlkvist, Tommy; Patra, Anuttam; Vilinska, Annamaria; Chernyshova, I. V.

    2013-01-01

    Large efforts are being made to streamline the conventional (chemical and physical) technological schemes of ore processing, remediation and environmental protection towards reducing overall costs, limiting the use of dangerous substances, decreasing waste streams and improving waste disposal and recycling practice. Hitherto, search for such innovations has been performed mainly empirically and there is an urgent need to shift these technologies to be more innovative and effective. Alternativ...

  3. Sludge thermal oxidation processes: mineral recycling, energy impact, and greenhouse effect gases release

    Energy Technology Data Exchange (ETDEWEB)

    Guibelin, Eric

    2003-07-01

    Different treatment routes have been studied for a mixed sludge: the conventional agricultural use is compared with the thermal oxidation processes, including incineration (in gaseous phase) and wet air oxidation (in liquid phase). The interest of a sludge digestion prior to the final treatment has been also considered according to the two major criteria, which are the fossil energy utilisation and the greenhouse effect gases (CO{sub 2}, CH{sub 4}, N{sub 2}O) release. Thermal energy has to be recovered on thermal processes to make these processes environmentally friendly, otherwise their main interest is to extract or destroy micropollutants and pathogens from the carbon cycle. In case of continuous energy recovery, incineration can produce more energy than it consumes. Digestion is especially interesting for agriculture: according to these two schemes, the energy final balance can also be in excess. As to wet air oxidation, it is probably one of the best way to minimize greenhouse effect gases emission. (author)

  4. Identifying opportunities to reduce the consumption of energy across mineral process and recovery plants

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, G. [Schneider Electric, Andover, MA (United States)

    2010-07-01

    In response to current market conditions and ongoing government policies, mining organizations are shifting focus towards sustainability and better utilization of energy. This presentation reviewed the role that an operations team plays in energy utilization and efficiency across the value chain. Mining companies want energy efficient solutions that identify and quantify potential energy savings in real dollar terms. A case study was presented to demonstrate that many continuous improvement processes can be adapted to identify the root causes of energy over consumption and to quantify the loss, or potential for saving, in real-time. The purpose of such an analysis is to improve decision making and to identify the most efficient operations equipment as well as the most effective process management and operational management. The analysis can help determine the lowest cost opportunities and validate data needed to justify capital intensive proposals for changes to equipment or processes, based on measurable energy savings. This will help organizations reduce energy consumption with the lowest investment. tabs., figs.

  5. Mineralization of C.I. Acid Red 14 azo dye by UV/Fe-ZSM5/H2O2, process.

    Science.gov (United States)

    Kasiri, Masoud B; Aleboyeh, Hamid; Aleboyeh, Azam

    2010-02-01

    The zeolite Fe-ZSM5 was applied as a heterogeneous catalyst in the photo-Fenton process for mineralization of azo dye Acid Red 14 (AR14). Under optimal conditions (20 mM of H2O2 0.25 g L(-1) of catalyst and initial natural pH of the solution) 76% of total organic carbon (TOC) of a solution containing 40 mg L(-1) of the dye could be removed after 120 min in a 1.0 L tubular, closed-circulation batch photoreactor. Leaching tests and comparative experiments indicated that the application of the heterogeneous catalyst could increase the photo-Fenton process efficiency. A kinetic model was developed for this process and showed that the dye mineralization rate obeyed the pseudo-first order kinetic when the initial concentration of the dye was low. It was also observed that the catalytic behaviour of Fe-ZSM5 could be reproduced in consecutive experiments without a considerable drop in the process efficiency. Estimation of electrical energy consumption (EE/O) of the process as a function of mineralization efficiency revealed that the UV/Fe-ZSM5/H2O2 process not only increased the mineralization efficiency of the process, but also decreased the cost of electrical energy consumed by the process.

  6. Fractionation and fluxes of metals and radionuclides during the recycling process of phosphogypsum wastes applied to mineral CO₂ sequestration.

    Science.gov (United States)

    Contreras, M; Pérez-López, R; Gázquez, M J; Morales-Flórez, V; Santos, A; Esquivias, L; Bolívar, J P

    2015-11-01

    The industry of phosphoric acid produces a calcium-rich by-product known as phosphogypsum, which is usually stored in large stacks of millions of tons. Up to now, no commercial application has been widely implemented for its reuse because of the significant presence of potentially toxic contaminants. This work confirmed that up to 96% of the calcium of phosphogypsum could be recycled for CO2 mineral sequestration by a simple two-step process: alkaline dissolution and aqueous carbonation, under ambient pressure and temperature. This CO2 sequestration process based on recycling phosphogypsum wastes would help to mitigate greenhouse gasses emissions. Yet this work goes beyond the validation of the sequestration procedure; it tracks the contaminants, such as trace metals or radionuclides, during the recycling process in the phosphogypsum. Thus, most of the contaminants were transferred from raw phosphogypsum to portlandite, obtained by dissolution of the phosphogypsum in soda, and from portlandite to calcite during aqueous carbonation. These findings provide valuable information for managing phosphogypsum wastes and designing potential technological applications of the by-products of this environmentally-friendly proposal.

  7. Hydrogeochemical processes governing the origin, transport and fate of major and trace elements from mine wastes and mineralized rock to surface waters

    Science.gov (United States)

    Nordstrom, D. Kirk

    2011-01-01

    The formation of acid mine drainage from metals extraction or natural acid rock drainage and its mixing with surface waters is a complex process that depends on petrology and mineralogy, structural geology, geomorphology, surface-water hydrology, hydrogeology, climatology, microbiology, chemistry, and mining and mineral processing history. The concentrations of metals, metalloids, acidity, alkalinity, Cl-, F- and SO42- found in receiving streams, rivers, and lakes are affected by all of these factors and their interactions. Remediation of mine sites is an engineering concern but to design a remediation plan without understanding the hydrogeochemical processes of contaminant mobilization can lead to ineffective and excessively costly remediation. Furthermore, remediation needs a goal commensurate with natural background conditions rather than water-quality standards that might bear little relation to conditions of a highly mineralized terrain. This paper reviews hydrogeochemical generalizations, primarily from US Geological Survey research, that enhance our understanding of the origin, transport, and fate of contaminants released from mined and mineralized areas.

  8. Mineralization of the recalcitrant oxalic and oxamic acids by electrochemical advanced oxidation processes using a boron-doped diamond anode.

    Science.gov (United States)

    Garcia-Segura, Sergi; Brillas, Enric

    2011-04-01

    Oxalic and oxamic acids are the ultimate and more persistent by-products of the degradation of N-aromatics by electrochemical advanced oxidation processes (EAOPs). In this paper, the kinetics and oxidative paths of these acids have been studied for several EAOPs using a boron-doped diamond (BDD) anode and a stainless steel or an air-diffusion cathode. Anodic oxidation (AO-BDD) in the presence of Fe(2+) (AO-BDD-Fe(2+)) and under UVA irradiation (AO-BDD-Fe(2+)-UVA), along with electro-Fenton (EF-BDD), was tested. The oxidation of both acids and their iron complexes on BDD was clarified by cyclic voltammetry. AO-BDD allowed the overall mineralization of oxalic acid, but oxamic acid was removed much more slowly. Each acid underwent a similar decay in AO-BDD-Fe(2+) and EF-BDD, as expected if its iron complexes were not attacked by hydroxyl radicals in the bulk. The faster and total mineralization of both acids was achieved in AO-BDD-Fe(2+)-UVA due to the high photoactivity of their Fe(III) complexes that were continuously regenerated by oxidation of their Fe(II) complexes. Oxamic acid always released a larger proportion of NH(4)(+) than NO(3)(-) ion, as well as volatile NO(x) species. Both acids were independently oxidized at the anode in AO-BDD, but in AO-BDD-Fe(2+)-UVA oxamic acid was more slowly degraded as its content decreased, without significant effect on oxalic acid decay. The increase in current density enhanced the oxidation power of the latter method, with loss of efficiency. High Fe(2+) contents inhibited the oxidation of Fe(II) complexes by the competitive oxidation of Fe(2+) to Fe(3+). Low current densities and Fe(2+) contents are preferable to remove more efficiently these acids by the most potent AO-BDD-Fe(2+)-UVA method.

  9. Measurements of cloud condensation nuclei activity and droplet activation kinetics of wet processed regional dust samples and minerals

    Science.gov (United States)

    Kumar, P.; Sokolik, I. N.; Nenes, A.

    2011-04-01

    This study reports laboratory measurements of particle size distributions, cloud condensation nuclei (CCN) activity, and droplet activation kinetics of wet generated aerosols from clays, calcite, quartz, and desert soil samples from Northern Africa, East Asia/China, and Northern America. The dependence of critical supersaturation, sc, on particle dry diameter, Ddry, is used to characterize particle-water interactions and assess the ability of Frenkel-Halsey-Hill adsorption activation theory (FHH-AT) and Köhler theory (KT) to describe the CCN activity of the considered samples. Regional dust samples produce unimodal size distributions with particle sizes as small as 40 nm, CCN activation consistent with KT, and exhibit hygroscopicity similar to inorganic salts. Clays and minerals produce a bimodal size distribution; the CCN activity of the smaller mode is consistent with KT, while the larger mode is less hydrophilic, follows activation by FHH-AT, and displays almost identical CCN activity to dry generated dust. Ion Chromatography (IC) analysis performed on regional dust samples indicates a soluble fraction that cannot explain the CCN activity of dry or wet generated dust. A mass balance and hygroscopicity closure suggests that the small amount of ions (of low solubility compounds like calcite) present in the dry dust dissolve in the aqueous suspension during the wet generation process and give rise to the observed small hygroscopic mode. Overall these results identify an artifact that may question the atmospheric relevance of dust CCN activity studies using the wet generation method. Based on a threshold droplet growth analysis, wet generated mineral aerosols display similar activation kinetics compared to ammonium sulfate calibration aerosol. Finally, a unified CCN activity framework that accounts for concurrent effects of solute and adsorption is developed to describe the CCN activity of aged or hygroscopic dusts.

  10. Processing, physico-chemical, sensory and nutritional evaluation of protein, mineral and vitamin enriched peanut chikki - an Indian traditional sweet.

    Science.gov (United States)

    Pallavi, Byrappa Vasu; Chetana, Ramakrishna; Reddy, Sunkireddy Yella

    2014-01-01

    Chikki, a popular Indian traditional sweet snack prepared from peanut was enriched with protein, minerals and vitamins by incorporating soy protein isolate, calcium carbonate, ferrous fumerate, vitamin A and folic acid to meet the growing demand for health foods. The enriched nutra chikki was evaluated for physico-chemical characteristics such as moisture, texture, peroxide value (PV), fatty acid composition in comparison with control peanut chikki. Nutra chikki, which had initial moisture content of 2-3%, did not alter much up to 60 days of storage at 27 °C and 37 °C. PV increased gradually at 27 °C, whereas at 37 °C, it was higher. Hardness of nutra chikki did not change significantly when stored at 27 °C up to 105 days, but at 37 °C a gradual increase in hardness was observed after 45 days. These results of nutra chikki were similar and comparable with those of control chikki. Nutra chikki had 18% protein, 20% fat, 6.42% Ca, 1.7% Fe, 4000 μg vitamin A and 2660 μg folic acid. Protein digestibility corrected amino acid score of nutra chikki was 0.78 whereas that of control chikki was 0.73. The fatty acid composition of control and nutra chikki was same as both contain peanuts as oil source. The formulation and process parameters for preparation of protein, mineral and vitamin enriched peanut chikki, were standardized. The storage stability and quality parameters of enriched chikki were comparable with those of control chikki.

  11. Measurements of cloud condensation nuclei activity and droplet activation kinetics of wet processed regional dust samples and minerals

    Directory of Open Access Journals (Sweden)

    P. Kumar

    2011-04-01

    Full Text Available This study reports laboratory measurements of particle size distributions, cloud condensation nuclei (CCN activity, and droplet activation kinetics of wet generated aerosols from clays, calcite, quartz, and desert soil samples from Northern Africa, East Asia/China, and Northern America. The dependence of critical supersaturation, sc, on particle dry diameter, Ddry, is used to characterize particle-water interactions and assess the ability of Frenkel-Halsey-Hill adsorption activation theory (FHH-AT and Köhler theory (KT to describe the CCN activity of the considered samples. Regional dust samples produce unimodal size distributions with particle sizes as small as 40 nm, CCN activation consistent with KT, and exhibit hygroscopicity similar to inorganic salts. Clays and minerals produce a bimodal size distribution; the CCN activity of the smaller mode is consistent with KT, while the larger mode is less hydrophilic, follows activation by FHH-AT, and displays almost identical CCN activity to dry generated dust. Ion Chromatography (IC analysis performed on regional dust samples indicates a soluble fraction that cannot explain the CCN activity of dry or wet generated dust. A mass balance and hygroscopicity closure suggests that the small amount of ions (of low solubility compounds like calcite present in the dry dust dissolve in the aqueous suspension during the wet generation process and give rise to the observed small hygroscopic mode. Overall these results identify an artifact that may question the atmospheric relevance of dust CCN activity studies using the wet generation method. Based on a threshold droplet growth analysis, wet generated mineral aerosols display similar activation kinetics compared to ammonium sulfate calibration aerosol. Finally, a unified CCN activity framework that accounts for concurrent effects of solute and adsorption is developed to describe the CCN activity of aged or hygroscopic dusts.

  12. Relevance of Toxicity Assessment in Wastewater Treatments: Case Study—Four Fenton Processes Applied to the Mineralization of C.I. Acid Red 14

    Science.gov (United States)

    Idel-aouad, Rajaa; Valiente, Manuel; Gutiérrez-Bouzán, Carmen; Vilaseca, Mercè; Yaacoubi, Abdlrani; Tanouti, Boumediene; López-Mesas, Montserrat

    2015-01-01

    Fenton and Fenton-like processes, both in homogeneous and heterogeneous phases, have been applied to an aqueous solution containing the dye AR 14 in order to study the mineralization and toxicity of the solutions generated after color elimination. The mineralization of AR 14 occurred slower than the decolorization. The Microtox analysis of the treated solutions showed low toxicity intrinsic to the chemicals used in the process rather than the degradation products obtained after the treatment of the dye solution. The dye degradation for the Fenton oxidation process was initially faster than for the Fenton-like process but after a short time, the four processes showed similar degradation yields. All processes have shown good results being the heterogeneous process the most convenient since the pH adjustment is not necessary, the catalyst is recovered and reused and the generation of contaminated sludge is avoided. PMID:26167334

  13. Heterogeneous fenton process using the mineral hematite for the discolouration of a reactive dye solution

    Directory of Open Access Journals (Sweden)

    F. V. F. Araujo

    2011-12-01

    Full Text Available This work reports a study on the heterogeneous Fenton reaction using hematite powder (Fe2O3 in suspension for the discolouration of the reactive dye Drimarene Red X-6BN in aqueous solutions. The efficiency of the process was studied as a function of the experimental conditions: initial pH; H2O2 dose; and hematite powder concentration; all of which showed a strong effect on the reaction kinetics. Under the best experimental conditions: pH = 2.5; H2O2 dose = 800 mg/L; and [Hematite] = 20 g/L, it was possible to remove about 99% of the initial colour in 120 minutes in a batch reaction at 25ºC. The analysis of the kinetic results suggests that the reaction is initiated by heterogeneous generation of free radicals on the hematite surface, but as soluble iron (III and iron (II species are released into the solution during the course of the reaction, a simultaneous homogeneous Fenton reaction step propagates and contributes to the overall reaction.

  14. Effects of soil moisture and soil depth on nitrogen mineralization process under Mongolian pine plantations in Zhanggutai sandy land, P. R. China

    Institute of Scientific and Technical Information of China (English)

    CHENFu-sheng; ZENGDe-hui; SINGHAnandNarain; CHENGuang-sheng

    2005-01-01

    The rates of soil N mineralization at soil depths of 0-15, 15-30, 30-45 and 45-0 cm and moisture regimes were measured at three sand-fixation plantations of Pinus sylve.stris var. mongolica by laboratory aerobic incubation method. The results showed that average rates of soil net N-mineralization across soil depth varied from 1.06 to 7.52 mg ~ kg 1.month qat soil depths from 0 to 60 cm. Statistical analyses indicated that the effects of different soil depths, moistures and their interactions on net N-mineralization rates were significant (P<0.05). The net N-mineralization rates significantly decreased with increasing soil depths and at depth 0-15 cm accounted for 60.52% of that at depth of 0-50 cm. There was no difference in soil net N-mineralization rates between half and fully-saturated water treatments, however these rates were substantially higher than that without water treatment (P < 0.05). The factors influencing N mineralization process have to be studied further in these semiarid pine ecosystems.

  15. Mineral chemistry, P-T-t paths and exhumation processes of mafic granulites in Dinggye, Southern Tibet

    Institute of Scientific and Technical Information of China (English)

    LIU; Shuwen; ZHANG; Jinjiang; SHU; Guiming; LI; Qiugen

    2005-01-01

    The mafic granulites in Dinggye, as various scale lense-shaped enclaves within the high Himalayan crystalline rock series, occur along mylonitic foliations at the junction between the Southern Tibetan Detachment System (STDS) and the Xainza-Dinggye normal fault system. The main lithological assemblage comprises garnet plagioclase pyroxenite, garnet two-pyroxene granulite, pyroxene garnet amphibolite and so on. The detailed petrological analyses show that these mafic granulites underwent at least four-stage metamorphic evolution. The first metamorphic stage, the garnet+clinopyroxene+quart mineral assemblage (M1) was probably formed under eclogite facies, the second stage, the plagioclase+clinopyroxene symplectite mineral assemblage (M2) was produced under high-pressure granulite facies by the early decompressive breakdown of M1 mineral assemblage, the third stage, the plagioclase+clinopyroxene+ hypersthene symplectite mineral assemblage (M3) was formed at granulite facies by the late period decompressive breakdown of M1 and M2 mineral assemblages and the final stage, plagioclase+hornblende mineral assemblage (M4) was formed by hydrolysis of earlier mineral assemblages during late uplifting. The detailed mineral composition analyses suggest that garnets and clinopyroxenes within M1 and M2 mineral assemblages display similar compositions to the equivalents in the B and C types of eclogites, whereas the M3 clinopyroxenes are akin to these of the same kind of minerals in the granulite. These mineral chemistry features and P-T estimates calculated by mineral thermometers and barometers indicate that the early stage relic porphyroblasts (M1) could be formed at the eclogite facies, the early decompressive breakdown (M2) occurred at the high-pressures granulite facies of 1.35―1.48 GPa and 625―675℃, the M3 mineral assemblage recorded the granulite facies of 0.7―0.95 GPa and 775―900℃ and M4 plagioglase+hornblende retrograde mineral assemblage was produced under

  16. Mines and mineral processing facilities in the vicinity of the March 11, 2011, earthquake in northern Honshu, Japan

    Science.gov (United States)

    Menzie, W. David; Baker, Michael S.; Bleiwas, Donald I.; Kuo, Chin

    2011-01-01

    U.S. Geological Survey data indicate that the area affected by the March 11, 2011, magnitude 9.0 earthquake and associated tsunami is home to nine cement plants, eight iodine plants, four iron and steel plants, four limestone mines, three copper refineries, two gold refineries, two lead refineries, two zinc refineries, one titanium dioxide plant, and one titanium sponge processing facility. These facilities have the capacity to produce the following percentages of the world's nonfuel mineral production: 25 percent of iodine, 10 percent of titanium sponge (metal), 3 percent of refined zinc, 2.5 percent of refined copper, and 1.4 percent of steel. In addition, the nine cement plants contribute about one-third of Japan's cement annual production. The iodine is a byproduct from production of natural gas at the Miniami Kanto gas field, east of Tokyo in Chiba Prefecture. Japan is the world's second leading (after Chile) producer of iodine, which is processed in seven nearby facilities.

  17. Efficient mineralization of the antibiotic trimethoprim by solar assisted photoelectro-Fenton process driven by a photovoltaic cell.

    Science.gov (United States)

    Zhang, Yanyu; Wang, Aimin; Tian, Xiujun; Wen, Zhenjun; Lv, Hanjiao; Li, Desheng; Li, Jiuyi

    2016-11-15

    In this study, a novel self-sustainable solar assisted photoelectro-Fenton (SPEF) system driven by a solar photovoltaic cell was developed for the efficient mineralization of antibiotic trimethoprim (TMP) in water. A comparative degradation of 200mgL(-1) TMP by RuO2/Ti anodic oxidation (AO), anodic oxidation with H2O2 electrogeneration (AO-H2O2), electro-Fenton (EF) and SPEF was investigated. SPEF was proved to exhibit the highest oxidation power, i.e., more than 80% TOC was removed after 360min SPEF treatment of 200mgL(-1) of TMP under optimal conditions at pH 3.0, 1.0mM Fe(2+) and 18mAcm(-2). Influences of current density, pH, initial Fe(2+) and initial TMP concentration on SPEF process were also studied. Ten aromatic intermediates generated from hydroxylation, carbonylation and demethylation reactions were identified using UPLC-QTOF-MS/MS system during the SPEF treatment, together with three carboxylic acids (oxamic, oxalic and formic acids) and two inorganic ions (NH4(+) and NO3(-)) measured. Therefore, a reasonable pathway of TMP degradation in SPEF process was proposed.

  18. Control of silicate weathering by interface-coupled dissolution-precipitation processes at the mineral-solution interface

    NARCIS (Netherlands)

    Ruiz-Agudo, Encarnacián; King, Helen E.; Patiño-Ĺpez, Luis D.; Putnis, Christine V.; Geisler, Thorsten; Rodriguez-Navarro, Carlos; Putnis, Andrew

    2016-01-01

    The mechanism of surface coating formation (the so-called surface altered layers [SALs] or leached layers) during weathering of silicate minerals is controversial and hinges on understanding the saturation state of the fluid at the dissolving mineral surface. Here we present in-situ data on the evol

  19. Mathematical model for bone mineralization

    Directory of Open Access Journals (Sweden)

    Svetlana V Komarova

    2015-08-01

    Full Text Available Defective bone mineralization has serious clinical manifestations, including deformities and fractures, but the regulation of this extracellular process is not fully understood. We have developed a mathematical model consisting of ordinary differential equations that describe collagen maturation, production and degradation of inhibitors, and mineral nucleation and growth. We examined the roles of individual processes in generating normal and abnormal mineralization patterns characterized using two outcome measures: mineralization lag time and degree of mineralization. Model parameters describing the formation of hydroxyapatite mineral on the nucleating centers most potently affected the degree of mineralization, while the parameters describing inhibitor homeostasis most effectively changed the mineralization lag time. Of interest, a parameter describing the rate of matrix maturation emerged as being capable of counter-intuitively increasing both the mineralization lag time and the degree of mineralization. We validated the accuracy of model predictions using known diseases of bone mineralization such as osteogenesis imperfecta and X-linked hypophosphatemia. The model successfully describes the highly non-linear mineralization dynamics, which includes an initial lag phase when osteoid is present but no mineralization is evident, then fast primary mineralization, followed by secondary mineralization characterized by a continuous slow increase in bone mineral content. The developed model can potentially predict the function for a mutated protein based on the histology of pathologic bone samples from mineralization disorders of unknown etiology.

  20. Nitrogen fractions and mineral content in different lupin species (Lupinus albus, Lupinus angustifolius, and Lupinus luteus). Changes induced by the alpha-galactoside extraction process.

    Science.gov (United States)

    Porres, Jesus M; Aranda, Pilar; López-Jurado, María; Urbano, Gloria

    2007-09-05

    The protein and mineral composition of different varieties of three different lupin species (Lupinus albus, Lupinus angustifolius, and Lupinus luteus) and the effect of alpha-galactoside removal by means of a hydroalcoholic extraction process on such composition were studied in relationship to nutrient distribution among the different anatomical parts of the seed (embryo, cotyledon, and seed coat). The extent of processing-derived protein insolubilization was assessed by both chemical and electrophoretic techniques and related to the amount of nitrogen soluble in H(2)O, NaCl, ethanol, NaOH, and sodium dodecyl sulfate/beta-mercaptoethanol (SDS/BME). The alpha-galactoside extraction process caused a significant increase in the amount of total and insoluble nitrogen and decreased the amount of soluble protein nitrogen, without affecting the content of soluble nonprotein nitrogen. alpha-Galactoside extraction was not effective at decreasing the levels of Mn present in lupins, and processing caused an increase in the content of this mineral in all of the species studied with the exception of L. albus var. multolupa. In general, the effect of processing on mineral content varied with the different lupin species, and mineral losses were lower in L. luteus.

  1. Hydrothermal minerals

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.

    -floor hydrothermal processes involving free circulation of seawater through ocean crust as convection. Heat flow, seafloor fracturing, permeability and fluid composition are the parameters governing the type and extent of mineralization. The chimney like... stream_size 23365 stream_content_type text/plain stream_name Refresher_Course_Mar_Geol_Geophys_2007_Lecture_Notes_78.pdf.txt stream_source_info Refresher_Course_Mar_Geol_Geophys_2007_Lecture_Notes_78.pdf.txt Content-Encoding UTF-8...

  2. Silicon materials task of the Low-Cost Solar Array Project: Phase IV. Effects of impurities and processing on silicon solar cells. Twenty-first quarterly report, October-December 1980

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, R.H.; Hanes, M.H.; Davis, J.R.; Rohatgi, A.; Rai-Choudhury, P.; Mollenkopf, H.C.

    1981-01-30

    The overall objective of this program is to define the effects of impurities, various thermochemical processes, and any impurity-process interactions upon the performance of terrestrial solar cells. The results of the study form a basis for silicon producers, wafer manufacturers, and cell fabricators to develop appropriate cost-benefit relationships for the use of less pure, less costly solar grade silicon. Cr is highly mobile in silicon even at temperatures as low as 600/sup 0/C. Contrasting with earlier data for Mo, Ti, and V, Cr concentrations vary from place to place in polycrystalline silicon wafers and the electrically-active Cr concentration in the polysilicon is more than an order of magnitude smaller than would be projected from single crystal impurity data. We hypothesize that Cr diffuses during ingot cooldown after groth, preferentially segregates to grain boundaries and becomes electrically deactivated. Both Al and Au introduce deep levels when grown into silicon crystals. Accelerated aging data from Ni-contaminated silicon imply that no significant impurity-induced cell performance reduction should be expected over a twenty-year device lifetime. Combined electrical bias and thermal stressing of silicon solar cells containing Nb, Fe, Cu, Ti, Cr, and Ag, respectively produces no performance loss after 100 hour exposures up to 225/sup 0/C. Ti and V, but not Mo, can be gettered from polycrystalline silicon by POCl/sub 3/ or HCl at temperatures of 1000 and 1100/sup 0/C.

  3. Experiences of a Multidisciplinary Course on Geo-Signal Processing from a DSP Perspective Offered in Electrical Engineering at King Fahd University of Petroleum and Minerals

    Science.gov (United States)

    Mousa, W. A.

    2012-01-01

    The purpose of this paper is to share the experience gained in, and the efforts made toward, introducing and implementing a new course in the challenging and important area of geophysical signal processing at the Electrical Engineering (EE) Department, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia. The new course,…

  4. Experiences of a Multidisciplinary Course on Geo-Signal Processing from a DSP Perspective Offered in Electrical Engineering at King Fahd University of Petroleum and Minerals

    Science.gov (United States)

    Mousa, W. A.

    2012-01-01

    The purpose of this paper is to share the experience gained in, and the efforts made toward, introducing and implementing a new course in the challenging and important area of geophysical signal processing at the Electrical Engineering (EE) Department, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia. The new course,…

  5. EIS and adjunct electrical modeling for material selection by evaluating two mild steels for use in super-alkaline mineral processing

    DEFF Research Database (Denmark)

    Bakhtiyari, Leila; Moghimi, Fereshteh; Mansouri, Seyed Soheil

    2012-01-01

    The production of metal concentrates during mineral processing of ferrous and non-ferrous metals involves a variety of highly corrosive chemicals which deteriorate common mild steel as the material of choice in the construction of such lines, through rapid propagation of localized pitting...

  6. The utilization of waste by-products for removing silicate from mineral processing wastewater via chemical precipitation.

    Science.gov (United States)

    Kang, Jianhua; Sun, Wei; Hu, Yuehua; Gao, Zhiyong; Liu, Runqing; Zhang, Qingpeng; Liu, Hang; Meng, Xiangsong

    2017-08-22

    This study investigates an environmentally friendly technology that utilizes waste by-products (waste acid and waste alkali liquids) to treat mineral processing wastewater. Chemical precipitation is used to remove silicate from scheelite (CaWO4) cleaning flotation wastewater and the waste by-products are used as a substitute for calcium chloride (CaCl2). A series of laboratory experiments is conducted to explain the removal of silicate and the characterization and formation mechanism of calcium silicate. The results show that silicate removal reaches 90% when the Ca:Si molar ratio exceeds 1.0. The X-ray diffraction (XRD) results confirm the characterization and formation of calcium silicate. The pH is the key factor for silicate removal, and the formation of polysilicic acid with a reduction of pH can effectively improve the silicate removal and reduce the usage of calcium. The economic analysis shows that the treatment costs with waste acid (0.63 $/m(3)) and waste alkali (1.54 $/m(3)) are lower than that of calcium chloride (2.38 $/m(3)). The efficient removal of silicate is confirmed by industrial testing at a plant. The results show that silicate removal reaches 85% in the recycled water from tailings dam. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Amino acid, fatty acid, and mineral profiles of materials recovered from rainbow trout (Oncorhynchus mykiss) processing by-products using isoelectric solubilization/precipitation.

    Science.gov (United States)

    Chen, Y-C; Tou, J C; Jaczynski, J

    2007-11-01

    Protein, lipid, and insolubles (bones, skin, scales, fins, insoluble protein, and more) were recovered from rainbow trout processing by-products by means of isoelectric solubilization/precipitation at basic pH and acidic pH. Isoelectric solubilization/precipitation of the trout processing by-products resulted in the recovery of protein that was higher (P processing by-products. Basic pH treatments yielded a higher (P processing by-products, indicating that the pH treatments had no effect on these FAs. Ca and P contents of the processing by-products exceeded the recommended dietary allowances (RDA), but Fe and Mg did not. Basic pH treatments yielded protein with the lowest (P minerals and the highest (P processing by-products effectively removed minerals from the recovered protein without removal of the bones, skin, scales, fins, and so on, prior to processing. The results indicated that isoelectric solubilization/precipitation, particularly at basic pH, permitted recovery of high-quality protein and lipids from fish processing by-products for human food uses; also, the recovered insolubles may be used in animal feeds as a source of minerals.

  8. Investigation of the synergistic effects for p-nitrophenol mineralization by a combined process of ozonation and electrolysis using a boron-doped diamond anode

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Cuicui [School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084 (China); Yuan, Shi [School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084 (China); Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Li, Xiang; Wang, Huijiao; Bakheet, Belal [School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084 (China); Komarneni, Sridhar [Department of Ecosystem Science and Management and Material Research Institute, 205 MRL Building, The Pennsylvania State University, University Park, PA 16802 (United States); Wang, Yujue, E-mail: wangyujue@tsinghua.edu.cn [School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084 (China); Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China)

    2014-09-15

    Graphical abstract: - Highlights: • Combining electrolysis with ozonation greatly enhances nitrophenol mineralization. • O{sub 3} can rapidly degrade nitrophenol to carboxylic acids in the bulk solution. • Carboxylic acids can be mineralized by ·OH generated from multiple sources in the electrolysis-O{sub 3} process. • Electrolysis and ozonation can compensate for each other's weakness on pollutant degradation. - Abstract: Electrolysis and ozonation are two commonly used technologies for treating wastewaters contaminated with nitrophenol pollutants. However, they are often handicapped by their slow kinetics and low yields of total organic carbon (TOC) mineralization. To improve TOC mineralization efficiency, we combined electrolysis using a boron-doped diamond (BDD) anode with ozonation (electrolysis-O{sub 3}) to treat a p-nitrophenol (PNP) aqueous solution. Up to 91% TOC was removed after 60 min of the electrolysis-O{sub 3} process. In comparison, only 20 and 44% TOC was respectively removed by individual electrolysis and ozonation treatment conducted under similar reaction conditions. The result indicates that when electrolysis and ozonation are applied simultaneously, they have a significant synergy for PNP mineralization. This synergy can be mainly attributed to (i) the rapid degradation of PNP to carboxylic acids (e.g., oxalic acid and acetic acid) by O{sub 3}, which would otherwise take a much longer time by electrolysis alone, and (ii) the effective mineralization of the ozone-refractory carboxylic acids to CO{sub 2} by ·OH generated from multiple sources in the electrolysis-O{sub 3} system. The result suggests that combining electrolysis with ozonation can provide a simple and effective way to mutually compensate the limitations of the two processes for degradation of phenolic pollutants.

  9. Distribution of clay minerals in marine sediments off Chennai, Bay of Bengal, India:Indicators of sediment sources and transport processes

    Institute of Scientific and Technical Information of China (English)

    Subramanian VEERASINGAM; Ramdoss VENKATACHALAPATHY; Thirunavukkarasu RAMKUMAR

    2014-01-01

    Clay mineralogy, texture size and statistical analyses were carried out on surface sediments from the continental shelf of Chennai, Bay of Bengal, India. The purpose of this study is to characterize the clay mineral distribution and its relation to the hydrodynamics off Chennai to identify the sources and transport pathways of the marine sediments. Characterization of clay minerals in coastal sediments by Fourier Transform Infrared (FTIR) spectroscopy has provided the association of quartz, feldspar, kaolinite, chlorite, illite and iron oxides (magnetite and hematite) derived from river catchments and coastal erosion. Kaolinite, chlorite, illite, iron oxides, and organic matter are the dominant minerals in Cooum, and Adayar region. High quartz and feldspar zones were identified in Marina, which are being confined the sand zone and paralleling the coast. The strong relationships among the wave energy density, sand, quartz and carbonate revealed that wave induced littoral drift system play a dominant role in transportation and deposition of sediments in the Chennai coast. The sediment texture and minerals data are in agreement well with the previous results of hydrodynamics and littoral drift models in this region. Multivariate statistical analyses (correlation, cluster and factor analyses) were carried out and obtained results suggested that clay minerals and organic matter are trapped in silt and clay particles, whereas quartz, feldspar and carbonate are associated with sand particles. Results of sediment sources and transport processes from this study will be useful to predict the fate of the pollutants released from land or the potential change in sediment delivery to coastal areas.

  10. Conflict minerals from the Democratic Republic of the Congo: global tantalum processing plants, a critical part of the tantalum supply chain

    Science.gov (United States)

    Papp, John F.

    2014-01-01

    The U.S. Geological Survey (USGS) analyzes mineral and metal supply chains to identify and describe major components of mineral and metal material flows from ore extraction, through intermediate forms, to a final product. Supply chain analyses may be used (1) to identify risks to the United States associated with the supply of critical and strategic minerals and metals and (2) to provide greater supply chain transparency so that policymakers have the fact-based information needed to formulate public policy. This fact sheet focuses on the post-mining/pre-consumer-product part of the tantalum supply chain. The USGS National Minerals Information Center (NMIC) has been asked by governmental and non-governmental organizations to provide information about tantalum, tin, tungsten, and gold (collectively known as “3TG minerals”) processing facilities worldwide in response to U.S. legislation aimed at identifying and removing the supply chain links between the trade in these minerals and civil unrest in the Democratic Republic of the Congo and adjacent countries.

  11. The investigation of degradation and mineralization of high concentrations of formaldehyde in an electro-Fenton process combined with the biodegradation.

    Science.gov (United States)

    Moussavi, Gholamreza; Bagheri, Amir; Khavanin, Ali

    2012-10-30

    This study was done to evaluate the degradation and mineralization of formaldehyde (≈ 8000 mg/L) in an electro-Fenton process (EFP) in combination with biodegradation. In the first step, the influence of several important parameters including solution pH, current density, H(2)O(2) concentration, and reaction time were tested on the efficiency of the EFP in degradation and mineralization of formaldehyde in a concentrated solution. The optimum pH and current density was found to be around 10 and 8.5 mA/cm(2), respectively. The formaldehyde degradation in the EFP increased with an increased H(2)O(2) concentration. Under optimum pH and current density, the complete degradation and 51% mineralization of formaldehyde was attained in the EFP using a H(2)O(2) concentration of 10mM/min at a short reaction time of 6 min. The biodegradation of the effluent of EFP under optimum conditions (complete formaldehyde removal) was also tested. The results demonstrated that the concentration of the EFP effluent could be efficiently reduced in the bioreactor to below 50mg/L after a biodegradation time of 16d. Accordingly, results showed that EFP was a very efficient process for degradation and mineralization of a high concentration of formaldehyde so that its effluent could be efficiently post-treated with a biological process.

  12. Microbial bio-mineralization processes in hydrothermal travertine: the case study of two active travertine systems (Tuscany, Italy).

    Science.gov (United States)

    Barilaro, Federica; Bontognali, Tomaso R. R.; Mc Kenzie, Judith A.; Vasconcelos, Crisogono

    2015-04-01

    Modern hydrothermal travertine deposits, occurring today at Bagni San Filippo (Radicofani Basin) and at Bagni di Saturnia (Albegna Valley) in Tuscany, Central Italy, have been investigated with the main purpose to improve the understanding of the processes that control calcium carbonate precipitation in hydrothermal-spring settings. Present-day thermal activity at Bagni di Saturnia is characterized by a 37.5°C thermal spring with a rate of about 800 l/s, with a pH of ca. 6.4. Thermal water discharges at Bagni San Filippo reach a rate of 20 litres per second at a maximum temperature of 50°C and a pH of ca. 7. The springs expel water enriched in H2S-CO2-SO42- and HCO3- and divalent cations (Ca and Mg). In the studied areas, travertine precipitation occurs in association with living microbial mats and biofilms, composed of a heterogeneous community of green algae, filamentous cyanobacteria and other types of prokaryotes, anoxygenic photosynthetic bacteria and heterotrophic heat-tolerant bacteria, with a variable amount of extracellular polymeric substances (EPS). Nine categories of fabric types, dominantly calcite and aragonite in composition, showing a wide range of macro- and micro-porosity, have been identified. High magnification analysis of dendritic and laminated boundstone, crystalline crust cementstone, raft boundstone, coated bubble boundstone, micrite mudstone and coated reed boundstone fabric types, suggests that precipitation occurs in association with organic matter. Diatoms, cyanobacteria filaments and other bacteria are then associated with the EPS and often appear totally or partially entombed (passively or actively) in it. Organic extracellular polymeric substances (EPS) and often the external surface of cyanobacterial sheaths are the location where the calcite minerals nucleate and grow. Precipitation begins with organomineral nano-globules consisting of nanometre-size, from sub-spherical to globular-like, raised structures (5 to 80 nm diameter

  13. Effect of Natural Mineral on Methane Production and Process Stability During Semi-Continuous Mono-Digestion of Maize Straw.

    Science.gov (United States)

    González-Suárez, A; Pereda-Reyes, I; Pozzi, E; da Silva, A José; Oliva-Merencio, D; Zaiat, M

    2016-04-01

    The effect of natural mineral on the mono-digestion of maize straw was evaluated in continuously stirred tank reactors (CSTRs) at 38 °C. Different strategies of mineral addition were studied. The organic loading rate (OLR) was varied from 0.5 to 2.5 g volatile solid (VS) L(-1) d(-1). A daily addition of 1 g mineral L(-1) in reactor 2 (R2) diminished the methane production by about 11 % with respect to the initial phase. However, after a gradual addition of mineral, an average methane yield of 257 NmL CH4 g VS(-1) was reached and the methane production was enhanced by 30 % with regard to R1. An increase in the frequency of mineral addition did not enhance the methane production. The archaeal community was more sensitive to the mineral than the bacterial population whose similarity stayed high between R1 and R2. Significant difference in methane yield was found for both reactors throughout the operation.

  14. Processes of Defragmentation, Thermocapillary Extraction and Agglomeration of Ultradispersed Gold from Mineral Raw Materials and Technogenic Products within Laser Radiation Field

    Directory of Open Access Journals (Sweden)

    A.P. Kuzmenko

    2013-10-01

    Full Text Available According to the analysis of the results of complex studies of mineral raw materials and man-handle products containing ultra-dispersed gold, silver, and platinum before and after laser treatment, a qualitative physical model which explains the origin of thermal processes occurring under the action of laser radiation is proposed. It is noted that laser treatment of those materials generates processes of defragmentation, thermocapillary extraction, and agglomeration of micro-and nanoinclusions of these metals.

  15. Investigating the influence of selected texture-improved pretreatment techniques on storage stability of wholegrain brown rice: Involvement of processing-induced mineral changes with lipid degradation.

    Science.gov (United States)

    Xia, Qiang; Wang, Liping; Yu, Wenjuan; Li, Yunfei

    2017-09-01

    This work aimed at investigating the effects of emerging texture-improved processing techniques including high hydrostatic pressure (HHP; 150-450MPa/10min), high-intensity ultrasonication (HIU; 17.83W·cm(-2)/30min) and germination (37°C/36h) pretreatments on lipid hydrolysis and oxidation development of wholegrain brown rice (WBR) during storage, in an attempt to ascertain a possible link between lipid degradation and the underlying mechanisms. The results showed that HHP and HIU treatments enhanced lipid hydrolysis and oxidation as indicated by the formation of free fatty acids (FFA) and thiobarbituric acid reactive substances (TBARS) respectively, whereas an opposite pattern was observed for germination. Storage process rather than after immediate treatments observed an increase in lipid oxidation of HHP and HIU-processed samples, which was related to processing-induced liberation of minerals. Quantitative and qualitative characterization via inductively coupled plasma-optical emission spectrometry (ICP-OES) and micro X-ray fluorescence (μ-XRF) analysis confirmed the shifts of mineral distribution in WBR grains in response to different pretreatments. The WBR-derived lipase was activated by Ca(2+), and μ-XRF mapping indicated calcium enrichment in pericarp/aleurone layer and its mobilization to embryo during germination process where magnesium and manganese were significantly reduced. Multivariate analysis revealed a close relationship between increased lipid degradation and minerals including magnesium and manganese. This is the first time for reporting the effects of selected texture-improved techniques on lipid stability of WBR grains across storage process as well as validating the involvement of processing-induced mineral release in lipid degradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Ergonomic interventions for improving working postures associated with manual materials handling (case study: a mineral processing plant

    Directory of Open Access Journals (Sweden)

    Fateme Dehghani

    2016-12-01

    Full Text Available Introduction: A high percentage of musculoskeletal disorders in workplaces occur due to awkward posture and non-ergonomic design of the work stations for lifting and carrying of materials. To avoid these injuries, jobs should be designed in a way that ergonomics risk factors are controlled properly. The aim of this study was to utilize ergonomics interventions to minimize ergonomics risk factors in bag packing unit in a mineral processing plant. Material and Method: This cross sectional study was carried out among 20 workers of bag packing unit. Camera recording of working postures, evaluation of medical records, interview, and REBA technique were used to identify the ergonomic risk factors. Interventions included changing the conveyor belt height and the use of spring pallets (spring table. Data were analyzed using Paired T-Test by SPSS software version 18. Result: Before implementing ergonomics intervention, a total of 75% of evaluated postures by REBA technique obtained score of 8-10 (very high risk level and 25% had score of 11-15 (very high risk level that correspond to the action level 3 and 4, respectively. Following the implementation of ergonomics interventions, a total of 90% of the analyzed postures showed action level 2 (moderate risk level and the remainder 10 percent of evaluated postures showed high risk level. Comparison of REBA technique scores before and after implementing interventions showed a significant difference (P-value < 0.05. Conclusion: Based on the findings of this study, the implementation of ergonomics interventions has remarkably decreased the required action level and it may be able to improve work-related postures.

  17. Investigation of the synergistic effects for p-nitrophenol mineralization by a combined process of ozonation and electrolysis using a boron-doped diamond anode.

    Science.gov (United States)

    Qiu, Cuicui; Yuan, Shi; Li, Xiang; Wang, Huijiao; Bakheet, Belal; Komarneni, Sridhar; Wang, Yujue

    2014-09-15

    Electrolysis and ozonation are two commonly used technologies for treating wastewaters contaminated with nitrophenol pollutants. However, they are often handicapped by their slow kinetics and low yields of total organic carbon (TOC) mineralization. To improve TOC mineralization efficiency, we combined electrolysis using a boron-doped diamond (BDD) anode with ozonation (electrolysis-O3) to treat a p-nitrophenol (PNP) aqueous solution. Up to 91% TOC was removed after 60 min of the electrolysis-O3 process. In comparison, only 20 and 44% TOC was respectively removed by individual electrolysis and ozonation treatment conducted under similar reaction conditions. The result indicates that when electrolysis and ozonation are applied simultaneously, they have a significant synergy for PNP mineralization. This synergy can be mainly attributed to (i) the rapid degradation of PNP to carboxylic acids (e.g., oxalic acid and acetic acid) by O3, which would otherwise take a much longer time by electrolysis alone, and (ii) the effective mineralization of the ozone-refractory carboxylic acids to CO2 by OH generated from multiple sources in the electrolysis-O3 system. The result suggests that combining electrolysis with ozonation can provide a simple and effective way to mutually compensate the limitations of the two processes for degradation of phenolic pollutants.

  18. Investigation of the mineral components of porcelain raw material and their phase evolution during a firing process by using a Rietveld quantitative analysis

    Science.gov (United States)

    Kim, Jaegyeom; Heo, Eunae; Kim, Seung-Joo; Kim, Jong-Young

    2016-01-01

    A ceramic raw material for white porcelain and its phase evolution during a firing process were investigated by using Rietveld method based on powder X-ray diffraction data. The raw material was mainly composed of five mineral phases: quartz (SiO2), microcline (KAlSi3O8), albite (NaAlSi3O8), muscovite (KAl2(AlSi3O10)(OH)2), and kaolinite (Al2Si2O5(OH)4). The amount of each mineral phase could be determined by using Rietveld quantitative phase analyses. During the firing process, the microcline, albite, muscovite and kaolinite phases started to react with each other to produce the mullite phase embedded in an amorphous matrix. The amount of quartz remained nearly unchanged until a temperature above 1200 °C; then, it converted to an amorphous phase at higher temperatures.

  19. Iron, zinc and phytic acid in rice from China: wet and dry processing towards improved mineral bioavailability

    NARCIS (Netherlands)

    Liang, J.

    2007-01-01

    Rice and rice products supply two thirds of Chinese people with their staple food. Mineral deficiencies, especially of iron and zinc, are prevalent in China, and are caused by insufficient intake and poor bioavailability. Rice and rice products contribute more than 50% of the antinutrient  phytic ac

  20. Research on Mineral Processing Process for Copper-Lead-Zinc Mine%某铜铅锌矿选矿工艺研究

    Institute of Scientific and Technical Information of China (English)

    熊锋

    2015-01-01

    青海某铜铅锌矿的矿石类型为原生硫化矿,针对原矿的物相分析及工艺矿物学研究,研究了一种比较适合该矿矿石的选矿工艺流程,最终可获得含锌54.10%、含铜0.39%、含铅0.24%的锌精矿,其锌回收率为90.90%,锌精矿含银36.1 g/t,回收率4.26%;得到含铜25.27%,含铅5.88%,含锌5.91%的铜精矿,铜的最终回收率80.48%,铜精矿中含银842 g/t;得到含铅37.78%,含铜1.60%,含锌8.35%的铅精矿,铅的最终回收率53.55%,铅精矿中含银3 880 g/t.%Ore type of a Qinghai copper-lead-zinc mine is primary sulfide ore, according to phase analysis of ROM ore and process mineralogy research, mineral processing process flow suitable for the type of ore is researched, zinc concentrate (including 54.10% zinc, 0.39% copper and 0.24% lead) will be obtained, in which zinc recovery of 90.90%, 36.1 g/t silver content in zinc concentrate, recovery of 4.26%;copper concentrate (including 25.27%copper, 5.88%lead and 5.91%zinc) will be obtained, in which copper recovery of 80.48%, 842 g/t silver content in copper concentrate; lead concentrate (including 37.78% lead, 1.60% copper, 8.35%zinc) will be obtained, in which lead recovery of 53.55%, 3 880 g/t silver in lead concentrate.

  1. Culture systems: mineral oil overlay.

    Science.gov (United States)

    Morbeck, Dean E; Leonard, Phoebe H

    2012-01-01

    Mineral oil overlay microdrop is commonly used during in vitro fertilization (IVF) procedures. Though mineral oil appears homogeneous, it is an undefined product that can vary in quality. Here, we describe the history, chemistry, processing, and optimal use of mineral oil for IVF and embryo culture.

  2. Twenty-first century vaccines

    Science.gov (United States)

    Rappuoli, Rino

    2011-01-01

    In the twentieth century, vaccination has been possibly the greatest revolution in health. Together with hygiene and antibiotics, vaccination led to the elimination of many childhood infectious diseases and contributed to the increase in disability-free life expectancy that in Western societies rose from 50 to 78–85 years (Crimmins, E. M. & Finch, C. E. 2006 Proc. Natl Acad. Sci. USA 103, 498–503; Kirkwood, T. B. 2008 Nat. Med 10, 1177–1185). In the twenty-first century, vaccination will be expected to eliminate the remaining childhood infectious diseases, such as meningococcal meningitis, respiratory syncytial virus, group A streptococcus, and will address the health challenges of this century such as those associated with ageing, antibiotic resistance, emerging infectious diseases and poverty. However, for this to happen, we need to increase the public trust in vaccination so that vaccines can be perceived as the best insurance against most diseases across all ages. PMID:21893537

  3. Twenty-First Century Educational Theory and the Challenges of Modern Education: Appealing to the Heritage of the General Teaching Theory of the Secondary Educational Curriculum and the Learning Process

    Science.gov (United States)

    Klarin, Mikhail V.

    2016-01-01

    The article presents an analysis of educational theory in light of the challenges confronting education in the twenty-first century. The author examines how our ideas about the methods for managing the transmission of culture, the subject of education, and the consequences of these changes for the theory of education have changed. The author…

  4. Chemical variations in the Triple Group of the Skaergaard intrusion: insights for the mineralization and crystallization process

    Science.gov (United States)

    Nielsen, T. F.; Bernstein, S.

    2009-12-01

    The 54 Ma. old Skaergaard intrusion ( East Greenland) is a type example for fractionation of basaltic melt along the Fenner Trend. The Triple Group is the upper most 100 m of the Middle Zone and consists of FeTi-oxide rich layered gabbro with three distinct leugabbro layers 2-5 m thick ( L-layers; L1-L3, 2-5m thick) and a less marked layer (L0) c.20 m below L1. These are the most marked of many such layers. Apart from the pronounced layering the lower part of the Triple Group also hosts a world class Au-PGE mineralization. The mineralization is perfectly concordant with the L-layers, and the Triple Group invites investigation of the relationship between host and mineralization. The mineralization includes 5 main levels defined by palladium concentration. The chemical variation across the mineralization is covered by ca. 250 bulk major and trace element compositions, each representing 25cm of stratigraphy giving a continuum of ca. 60m. Proportions of normative plagioclase (plag) and pyroxene (px, including cpx and opx) are complementary, except in mineralized gabbro which is rich in FeTi-oxides. Cumulus ilmenite (ilm) is strongly enriched in layers (7m apart). They occur in both plag- and px-rich gabbro, whereas magnetite (mt) shows no simple correlation with ilm and is mainly a poikilitic intercumulus phase. The L-layers are composed of an upper part rich in plag and px and poor in FeTi-oxides, and a lower part rich in plag and FeTi-oxides and poor in px. The marked breaks in the mineralogy in the L-layers separate one layered succession from the next. The layered successions consist of a lower oxide-poor px-plag adcumulate, followed by complex mesocratic orthocumulate with poikilitic interstitial FeTi-oxide, and an upper part of increasingly simple plag-rich adcumulate with decreasing content of interstitial mt. The Au-PGE mineralized levels are found in the complex FeTi-rich gabbros at and in the base of the leucogabbro layers. The stratigraphic variation in

  5. Depth-Dependent Mineral Soil CO2 Production Processes: Sensitivity to Harvesting-Induced Changes in Soil Climate.

    Science.gov (United States)

    Kellman, Lisa; Myette, Amy; Beltrami, Hugo

    2015-01-01

    Forest harvesting induces a step change in the climatic variables (temperature and moisture), that control carbon dioxide (CO2) production arising from soil organic matter decomposition within soils. Efforts to examine these vertically complex relationships in situ within soil profiles are lacking. In this study we examined how the climatic controls on CO2 production change within vertically distinct layers of the soil profile in intact and clearcut forest soils of a humid temperate forest system of Atlantic Canada. We measured mineral soil temperature (0, 5, 10, 20, 50 and 100 cm depth) and moisture (0-15 cm and 30-60 cm depth), along with CO2 surface efflux and subsurface concentrations (0, 2.5, 5, 10, 20, 35, 50, 75 and 100 cm depth) in 1 m deep soil pits at 4 sites represented by two forest-clearcut pairs over a complete annual cycle. We examined relationships between surface efflux at each site, and soil heat, moisture, and mineral soil CO2 production. Following clearcut harvesting we observed increases in temperature through depth (1-2°C annually; often in excess of 4°C in summer and spring), alongside increases in soil moisture (30%). We observed a systematic breakdown in the expected exponential relationship between CO2 production and heat with mineral soil depth, consistent with an increase in the role moisture plays in constraining CO2 production. These findings should be considered in efforts to model and characterize mineral soil organic matter decomposition in harvested forest soils.

  6. Simulated atmospheric processing of iron oxyhydroxide minerals at low pH: roles of particle size and acid anion in iron dissolution.

    Science.gov (United States)

    Rubasinghege, Gayan; Lentz, Robert W; Scherer, Michelle M; Grassian, Vicki H

    2010-04-13

    A number of recent studies have shown that iron dissolution in Fe-containing dust aerosol can be linked to source material (mineral or anthropogenic), mineralogy, and iron speciation. All of these factors need to be incorporated into atmospheric chemistry models if these models are to accurately predict the impact of Fe-containing dusts into open ocean waters. In this report, we combine dissolution measurements along with spectroscopy and microscopy to focus on nanoscale size effects in the dissolution of Fe-containing minerals in low-pH environments and the importance of acid type, including HNO(3), H(2)SO(4), and HCl, on dissolution. All of these acids are present in the atmosphere, and dust particles have been shown to be associated with nitrate, sulfate, and/or chloride. These measurements are done under light and dark conditions so as to simulate and distinguish between daytime and nighttime atmospheric chemical processing. Both size (nano- versus micron-sized particles) and anion (nitrate, sulfate, and chloride) are found to play significant roles in the dissolution of alpha-FeOOH under both light and dark conditions. The current study highlights these important, yet unconsidered, factors in the atmospheric processing of iron-containing mineral dust aerosol.

  7. Physical setting and characteristics of high-sulfidation epithermal gold-silver deposits of the Andes and controls on mineralizing processes

    Science.gov (United States)

    Bissig, T.

    2013-05-01

    any conceivable rock type including granulite facies metamorphic rocks (California-Vetas mining district), significantly older plutonic rocks (Pascua-Lama) or quartzites (Lagunas Norte). Hydrothermal breccias are ubiquitous. Large vuggy quartz alteration zones and low grade, large tonnage mineralization are best developed in relatively permeable felsic volcaniclastic rocks whereas coherent volcanic, plutonic, or metamorphic rocks may host fracture and breccia controlled ore. Acid sulfate alteration and residual vuggy quartz normally pre-date mineralization whereas precious metals precipitate together with finegrained euhedral quartz from later, less acidic fluids. The physical and tectonic setting of high-sulfidation epithermal deposits is distinct from low-sulfidation epithermal deposits such as El Peñón (Chile), Fruta del Norte (Ecuador) or those of Patagonia. The latter range to significantly older ages (Jurassic to early Eocene), occur at lower elevations and were emplaced in extensional settings. A temporal coincidence between uplift, erosion and mineralizing processes as well as a spatial and temporal association with porphyry style mineralization is not evident for low-sulfidation districts.

  8. Mineral-vegetal co-milling: An effective process to improve lignocellulosic biomass fine milling and to increase interweaving between mixed particles.

    Science.gov (United States)

    Motte, J-C; Delenne, J-Y; Rouau, X; Mayer-Laigle, C

    2015-09-01

    Fine-milling is a crucial objective for lignocellulosic biomass valorization. Co-milling appears to be a promising technique to improve its efficiency. However, the mechanisms occurring while co-milling remain poorly understood. In this study, an experimental work was performed to produce co-milled powders from both lignocellulosic (wheat, straw or pine sawdust) and mineral materials (limestone, quartzite or tile) with very contrasted physicochemical properties. The main consequences of co-milling were studied for both materials. A two-component mixing law for the prediction of the blend properties was proposed (particle sizes and true densities) to highlight the gain of this single processing step compared to separate milling and mixing. The predicted values were compared with experimental data for co-milled powders at 7 biomass contents from 0% to 100%. In all cases, co-milling leads to a reduction in particle size of lignocellulosic materials and create strong interweaving with mineral particles.

  9. Variable mineralization processes during the formation of the Permian Hulu Ni-Cu sulfide deposit, Xinjiang, Northwestern China

    Science.gov (United States)

    Zhao, Yun; Xue, Chunji; Zhao, Xiaobo; Yang, Yongqiang; Ke, Junjun; Zu, Bo

    2016-08-01

    The Permian Hulu Ni-Cu sulfide deposit is located at the southern margin of the Central Asian Orogenic Belt (CAOB) in Northern Xinjiang, Northwestern China. The host intrusion of the Hulu deposit is composed of a layered mafic-ultramafic sequence and a dike-like unit. The layered sequence is composed of harzburgite, lherzolite, pyroxenite, gabbro, gabbrodiorite and diorite. The dike-like body comprises lherzolite and gabbro. Sulfide orebodies occur mainly within the harzburgite, pyroxenite and lherzolite at the base of the layered sequence and within the lherzolite in the dike-like body. Sulfide mineralization from the Hulu deposit shows significant depletion of PGE relative to Cu and Ni. These elements show good positive correlations with S in the sulfide mineralization from the dike-like unit but relatively weak correlations in the sulfide mineralization from the layered sequence. The sulfide mineralization from the layered unit shows excellent positive correlations between Ir and Os, Ru or Rh, and poor relationships between Ir and Pt or Pd. On the contrary, sulfide mineralization from the dike-like unit shows good correlations in the diagrams of Os, Ru, Rh, Pt and Pd against Ir. Both high Cu/Pd ratios (8855-481,398) and our modeling indicate that PGE depletion resulted from sulfide removal in a deep staging magma chamber. The evolved PGE-depleted magmas then ascended to the shallower magma chamber and became sulfide saturation due to crustal contamination. Both low Se/S ratios (33.5 × 10-6-487.5 × 10-6) and a negative correlation between Se/S and Cu/Pd ratios are consistent with the addition of crustal S. A large number of sulfide liquids segregated with minor crystallization of monosulfide solid solution (MSS) in the shallower magma chamber. When new magma pulses with unfractionated sulfide droplets entered the shallower magma chamber, the sulfide slurry containing crystallized MSS may be disrupted and mixed with the unfractionated sulfide droplets. The

  10. Proceedings of the 45. annual conference of metallurgists of CIM : interfacial phenomena in fine particle technology : the 6. UBC-McGill-UA international symposium on fundamentals of mineral processing in honor of Professor Janusz S. Laskowski

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Liu, Q. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering] (eds.)

    2006-07-01

    This conference, organized by the Mineral Sciences and Engineering Section of the Metallurgical Society of CIM acknowledged that strong economic growth is the driving force behind record high productivity in the mining industry. The industry must strive to meet the higher demand for raw materials while facing the challenge of stringent environmental constraints. The continuing success of the mining industry will depend on efficient and environmentally sound mineral processing, particularly since the industry has been forced to exploit more complex forms of minerals given the gradual depletion of high-grade mineral resources. In addition to shortages in qualified personnel in mineral processing, the industry is currently facing a general reduction in basic research and training programs, resulting in deficiencies in technologies needed to process complex ores. World experts in mineral processing participated at this conference to share their novel research in fine particle processing, applications of atomic force microscopy, flotation research, particle interactions in mineral processing, flotation froths, grinding, rheology and sulphide flotation chemistry. The sessions of the conference were entitled: atomic force microscopy in flotation research particulate interactions; flotation froths, flocculation and dewatering; grinding and rheology surfactants; flotation froths, particle-bubble interactions; sulphide flotation; and, general flotation froths. The conference featured 37 presentations, of which 6 have been catalogued separately for inclusion in this database. refs., tabs., figs.

  11. Application of passive sonar technology to mineral processing and oil sands applications : if you can measure it, you can manage it

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, C.; Viega, J.; Fernald, M. [CiDRA Corp., Wallingford, CT (United States)

    2007-07-01

    SONAR-based flow and entrained air measurement instruments were described. This new class of industrial flow and compositional analyzers was developed by CiDRA to provide new measurement insight and quantifiable value to industrial process operators. Passive sonar array-based processing units have been installed worldwide in several industrial applications and are particularly suited for a wide range of mineral processing applications, including slurry flow rate measurement and fluid characterization. This paper also described the SONAR-based, clamp-on SONARtrac technology, a scalable platform that provides several other value added measurements and information such as speed of sound, entrained air/gas, gas hold-up, and velocity profile. Oil sands, tailings and bitumen slurries present considerable measurement challenges for in-line flow measurement devices in terms of measurement accuracy, reliability and maintenance. The sonar-based technology platform has been used in a variety of oil sands processes, hydrotransport, and minerals beneficiation applications. This paper described these applications with particular reference to difficult slurry flow measurement and control in the areas of comminution and flotation such as mill discharge, hydrocyclone feed/overflow, final concentrate, thickener discharge, and tailings. 5 refs., 4 tabs., 23 figs.

  12. Modification, adsorption, and geochemistry processes on altered minerals and amorphous phases on the nanometer scale: examples from copper mining refuse, Touro, Spain.

    Science.gov (United States)

    Civeira, Matheus; Oliveira, Marcos L S; Hower, James C; Agudelo-Castañeda, Dayana M; Taffarel, Silvio R; Ramos, Claudete G; Kautzmann, Rubens M; Silva, Luis F O

    2016-04-01

    The sulfide oxidation and precipitation of Al-Fe-secondary minerals associated with abandoned acid mine drainage (AMD) from the abandoned copper mine waste pile at Touro, Spain, has been studied by sequential extraction (SE) combined with several techniques with the intent of understanding the role of these processes play in the natural attenuation of hazardous element contaminants in the AMD. In addition, the fragile nature of nanominerals and ultrafine particle (UFP) assemblages from contaminated sediment systems from the abandoned copper mine required novel techniques and experimental approaches. The investigation of the geochemistry of complex nanominerals and UFP assemblages was a prerequisite to accurately assess the environmental and human health risks of contaminants and cost-effective chemical and biogeological remediation strategies. Particular emphasis was placed on the study and characterization of the complex mixed nanominerals and UFP containing potentially toxic elements. Nanometer-sized phases in sediments were characterized using energy-dispersive X-ray spectrometer (EDS), field-emission scanning electron microscope (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM) images. The identification of the geochemical and mineralogical composition of AMD in Touro, as well as the different formation mechanisms proposed, complement the existing literature on secondary mineral assemblages and provide new emphasis to increase the understanding of extreme environments. The results also demonstrated that variations in the geochemical fractionation of hazardous elements in AMD were more influenced by the secondary mineral proportion and by AMD pH.

  13. Mineral Commodity Summaries 2008

    Science.gov (United States)

    ,

    2008-01-01

    Inventory) are the basis for some reserves and reserve base estimates. The USGS collects information about the quantity and quality of mineral resources but does not directly measure reserves, and companies or governments do not directly report reserves or reserve base to the USGS. Reassessment of reserves and reserve base is a continuing process and the intensity of this process differs for mineral commodities, countries, and time period. Abbreviations and units of measure, and definitions of selected terms used in the report, are in Appendix A and Appendix B, respectively. A resource/reserve classification for minerals, based on USGS Circular 831 (published with the U.S. Bureau of Mines) is Appendix C, and a directory of USGS minerals information country specialists and their responsibilities is Appendix D. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the MCS 2008 are welcomed.

  14. Experimental Study on Mineral Processing of Low-grade Cu-Ni Ore%某低品位铜镍矿选矿试验研究

    Institute of Scientific and Technical Information of China (English)

    王潇

    2012-01-01

    A low-grade copper-nickel sulfide ore contains nickel 0.63 %,copper 0.62 %,and there are a lot of magnesium oxide minerals in the gangue minerals,including olivine,serpentine,chlorite,pyroxene,etc.According to mineral characters,the flotation test of the ore is studied.By experimenting,regulating and optimizing the technical parameter,we use the site production process and gets the qualified concentrate: nickel grade was 6.11 %,nickel recovery rate reaches 72.03 %,and copper grade was 7.06 %,copper recovery rate reaches 78.61 %.That not only improves resource utilization,but also provides a reasonable way for sustainable development of mineral enterprise.%某低品位硫化铜镍矿含镍0.63%、含铜0.62%,脉石矿物主要以橄榄石、蛇纹石、绿泥石、辉石等含镁矿物为主。根据矿石性质,对其进行了浮选试验研究,采用现场生产工艺流程,通过试验调整、优化工艺参数后得到了镍品位6.11%、回收率72.30%和铜品位7.06%,回收率78.61%的合格精矿,提高了资源利用率,为矿山可持续发展提供了合理的途径。

  15. Carbon Mineral Ecology: Predicting the Undiscovered Minerals of Carbon

    Science.gov (United States)

    Hazen, R. M.; Hummer, D. R.; Downs, R. T.; Hystad, G.; Golden, J.

    2015-12-01

    The diversity and distribution of Earth's minerals through deep time reflects key events in our planet's crustal evolution. Studies in mineral ecology exploit mineralogical databases to document diversity-distribution relationships of minerals, which reveal that all carbon-bearing minerals, as well as subsets containing C with O, H, Ca, or Na, conform to Large Number of Rare Events (LNRE) distributions. LNRE models facilitate prediction of total mineral diversity, and thus point to minerals that exist on Earth but have not yet been discovered and described. Our model predicts that at least 548 C minerals exist on Earth today, indicating that at least 145 carbon-bearing mineral species have yet to be discovered. Furthermore, by analyzing subsets of the most common additional elements in carbon-bearing minerals (i.e., 378 C + O species; 282 C + H species; 133 C + Ca species; and 100 C + Na species), we predict that 129 of these missing carbon minerals contain oxygen, 118 contain hydrogen, 52 contain calcium, and more than 60 contain sodium. The majority of these as yet undescribed minerals are predicted to be hydrous carbonates, many of which may have been overlooked because they are colorless, poorly crystalized, and/or water-soluble. We propose the identities of plausible as yet undescribed carbon minerals, as well as search strategies for their discovery. Some of these minerals will be natural examples of known synthetic compounds, including carbides such as calcium carbide (CaC2), crystalline hydrocarbons such as pyrene (C16H10), and numerous oxalates, anhydrous carbonates, and hydrous carbonates. Many other missing carbon minerals will be isomorphs of known carbon minerals, notably of the more than 100 different hydrous carbonate structures. An understanding of Earth's "missing" minerals provides a more complete picture of geochemical processes that influence crustal evolution.

  16. Why Mineral Interfaces Matter

    Science.gov (United States)

    Putnis, Andrew; Putnis, Christine V.

    2015-04-01

    While it is obvious that reactions between a mineral and an aqueous solution take place at the mineral-fluid interface it is only relatively recently that high spatial resolution studies have demonstrated how the local structure of the mineral surface and the chemical composition of the fluid at the interface control both the short-range and the long-range consequences of mineral-fluid interaction. Long-range consequences of fluid-mineral interaction control element cycles in the earth, the formation of ore-deposits, the chemical composition of the oceans through weathering of rocks and hence climate changes. Although weathering is clearly related to mineral dissolution, to what extent do experimentally measured dissolution rates of minerals help to understand weathering, especially weathering mechanisms? This question is related to the short-range, local reactions that take place when a mineral, that is not stable in the fluid, begins to dissolve. In this case the fluid composition at the interface will become supersaturated with respect to a different phase or phases. This may be a different composition of the same mineral e.g. a Ca-rich feldspar dissolving in a Na-rich solution results in a fluid at the interface which may be supersaturated with respect to an Na-rich feldspar. Alternatively, the interfacial fluid could be supersaturated with respect to a different mineral e.g. an Na-rich zeolite, depending on the temperature. Numerous experiments have shown that the precipitation of a more stable phase at the mineral-fluid interface results in a coupling between the dissolution and the precipitation, and the replacement of one mineral by another. This process separates the short-range mechanisms which depend only on the composition of the interfacial solution, and the long-range consequences that depend on the composition of the residual fluid released from the reacting parent mineral. Typically such residual fluids may carry metal ions tens to hundreds of

  17. An integrated study of uranyl mineral dissolution processes. Etch pit formation, effects of cations in solution, and secondary precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, M. [Laurentian Univ., Sudbury, ON (Canada). Dept. of Earth Sciences; Hawthorne, F.C. [Manitoba Univ., Winnipeg, MB (Canada). Dept. of Geological Sciences; Mandaliev, P. [Eidgenoessische Technische Hochschule (ETH), Zurich (Switzerland). Dept. of Environmental Sciences; Burns, P.C.; Maurice, P.A. [Notre Dame Univ., IN (United States). Dept. of Civil Engineering and Geological Sciences

    2011-07-01

    Understanding the mechanism(s) of uranium-mineral dissolution is crucial for predictive modeling of U mobility in the subsurface. In order to understand how pH and type of cation in solution may affect dissolution, experiments were performed on mainly single crystals of curite, Pb{sup 2+}{sub 3}(H{sub 2}O){sub 2}[(UO{sub 2}){sub 4}O{sub 4}(OH){sub 3}]{sub 2}, becquerelite, Ca(H{sub 2}O){sub 8}[(UO{sub 2}){sub 6}O{sub 4}(OH){sub 6}], billietite, Ba(H{sub 2}O){sub 7}[(UO{sub 2}){sub 6}O{sub 4}(OH){sub 6}], fourmarierite Pb{sup 2+}{sub 1-x}(H{sub 2}O){sub 4}[(UO{sub 2}){sub 4}O{sub 3-2x}(OH){sub 4+2x}] (x= 0.00-0.50), uranophane, Ca(H{sub 2}O){sub 5}[(UO{sub 2})(SiO{sub 3}OH)]{sub 2}, zippeite, K{sub 3}(H{sub 2}O){sub 3}[(UO{sub 2}){sub 4}(SO{sub 4}){sub 2}O{sub 3}(OH)], and Na-substituted metaschoepite, Na{sub 1-x}[(UO{sub 2}){sub 4}O{sub 2-x}(OH){sub 5+x}] (H{sub 2}O){sub n}. Solutions included: deionized water; aqueous HCl solutions at pH 3.5 and 2; 0.5 mol L{sup -1} Pb(II)-, Ba-, Sr-, Ca-, Mg-, HCl solutions at pH 2; 1.0 mol L{sup -1} Na- and K-HCl solutions at pH 2; and a 0.1 mol L{sup -1} Na{sub 2}CO{sub 3} solution at pH 10.5. Uranyl mineral basal surface microtopography, micromorphology, and composition were examined prior to, and after dissolution experiments on micrometer scale specimens using atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. Evolution of etch pit depth at different pH values and experimental durations can be explained using a stepwave dissolution model. Effects of the cation in solution on etch pit symmetry and morphology can be explained using an adsorption model involving specific surface sites. Surface precipitation of the following phases was observed: (a) a highly-hydrated uranyl-hydroxy-hydrate in ultrapure water (on all minerals), (b) a Na-uranyl-hydroxy-hydrate in Na{sub 2}CO{sub 3} solution of pH 10.5 (on uranyl-hydroxy-hydrate minerals), (c) a Na-uranyl-carbonate on zippeite, (d) Ba- and

  18. Influência do processamento no teor de minerais em sucos de maçãs Influence of the processing of apple juice in mineral content

    Directory of Open Access Journals (Sweden)

    Alessandro Nogueira

    2007-06-01

    Full Text Available A produção brasileira de maçãs apresenta 130 mil toneladas de frutas classificadas como descarte, que são anualmente transformadas em suco de maçã e exportadas na forma de concentrado. Alguns minerais têm apresentado teores abaixo dos padrões de qualidade internacionais, comprometendo a autenticidade e comercialização desse produto. Este trabalho teve como objetivos: quantificar os principais minerais em diferentes cultivares de maçãs e verificar o efeito das operações de processamento no teor de minerais, em sucos de maçãs. Foi avaliado, em diferentes cultivares de maçã, o teor de minerais na fruta e nos sucos obtidos por prensagem e liquefação enzimática. O teor de cinzas nas frutas das cultivares Gala (15,6 ± 0,8 g.kg -1 e Fuji (15,1 ± 0,5 g.kg -1 foi inferior ao das demais cultivares brasileiras (20,3 ± 2,6 g.kg -1. No processamento do suco por prensagem, apenas 15% das cinzas da fruta foram transferidas para o suco, contra 23% pelo processo de extração por liquefação, permanecendo grande quantidade de minerais no bagaço. O suco de maçã apresentou teores de minerais compatíveis com a International Federation of Fruit Juice Producers (IFU, entretanto, o teor de magnésio (29,24 ± 6,10 mg.L-1 ficou abaixo do limite preconizado pela IFU e o teor de cálcio (38,21 ± 7,20 mg.L-1 foi inferior aos valores da literatura e muito próximo do limite mínimo permitido, o que indica que estes minerais, nos sucos de maçãs processados no país, apresentam baixos teores.The Brazilian apple production discards 130,000 tons of classified fruit that is annually transformed into apple juice and exported as concentrate. Some minerals have presented contents below the international standards of quality, which in turn is problematic concerning authenticity and commercialization. This aims of this work are to quantify the main minerals in different apple varieties and to observe the effect of processing operations on mineral

  19. Effect of Soaking, Cooking, Germination and Fermentation Processing on Proximate Analysis and Mineral Content of Three White Sorghum Varieties (Sorghum bicolor L. Moench

    Directory of Open Access Journals (Sweden)

    Hossam Saad El-BELTAGI

    2012-11-01

    Full Text Available The changes in chemical composition, amylose and minerals content after soaking, cooking, germination and fermentation of threewhite sorghum varieties, named ‘Dorado’, ‘Shandaweel-6’, and ‘Giza-15’ were investigated. The chemical composition concluded includingcrude protein, oils, crude fiber and ash. Crude protein content ranged from 10.62 to 12.46% in raw sorghum. ‘Shandaweel-6’ was thehighest variety in crude protein content (12.46%. ‘Dorado’ was the highest variety in oils and ash (3.91 and 1.45%. ‘Shandaweel-6’ wasthe highest variety in crude fiber (1.85%. Amylose content ranged from 18.30 to 20.18% in raw sorghum. Amylose was higher in ‘Giza-15’ than other varieties. Minerals content i.e., Zn, Fe, Ca, K, Na, Mg, Mn and Cu were investigated. Results indicated that raw ‘Dorado’was the highest variety in K, Mg, Ca, Fe and Mn (264.53, 137.14, 33.09, 7.65 and 1.98 mg/100g. While, ‘Shandaweel-6’ was the highestvariety in Zn and Cu (5.02 and 0.84 mg/100 g. Finally ‘Giza-15’ was the highest variety in P and Na (381.37 and 119.29 mg/100 g.After treatments chemical composition, amylose and minerals were decreased. Processing techniques reduce the levels of antinutritionalorganic factors, which including phytates, phenols, tannins and enzyme inhibitors by releasing exogenous and endogenous enzymes suchas phytase enzyme formed during processing.

  20. Minerals in environmental technology

    Energy Technology Data Exchange (ETDEWEB)

    Schuiling, R.D. [Utrecht Univ., Utrecht (Netherlands). Faculty of Earth Sciences

    2000-07-01

    Minerals play a key role in the environment; this role is often not well understood, because the emphasis of most environmentalists is on air, water, or the composition of solid wastes as a whole, without paying attention to their mineralogical composition. Several minerals can serve as effective and cheap adsorbents for many toxic chemicals. Several minerals can be used as a cheap substitute for expensive chemicals in environmental technologies. Environmental technologies that produce an economically interesting mineral will have an edge over competing technologies. Most of the problems, overreaction, panicky and expensive measures with regard to exposure from quartz and asbestos stem from a poor understanding of natural levels of common contaminants, a disregard for mineralogy, and a lack of insight into natural processes in general.

  1. Proceedings of the twenty-sixth annual Institute on Mining Health, Safety and Research

    Energy Technology Data Exchange (ETDEWEB)

    Tinney, G.R.; Bacho, A.; Karmis, M. [eds.

    1995-12-31

    The proceedings of the Twenty-Sixth Annual Institute on Mining Health, Safety and Research are presented. The Conference was held in Blacksburg, Virginia on August 28-30, 1995 and covered such topics as themes of change, miner`s safety, personal and corporate liability, behavioral changes and positive reinforcement, and meeting health and safety objectives in mining operations. A separate abstract was prepared for the thirteen papers for inclusion in the Energy Science and Technology Database.

  2. Aggregate and Mineral Resources - Minerals

    Data.gov (United States)

    NSGIC State | GIS Inventory — This point occurrence data set represents the current mineral and selected energy resources of Utah. The data set coordinates were derived from USGS topographic maps...

  3. Electrochemical decontamination of waters by advanced oxidation processes (aops: Case of the mineralization of 2,4,5-t on bdd electrode

    Directory of Open Access Journals (Sweden)

    Birame Boye

    2004-12-01

    Full Text Available In the present work, herbicide 2,4,5-trichlorophenoxyacetic acid, more commonly known as 2,4,5-T herbicide, has been completely mineralized (i.e. transformed into CO2 and H2O in saturated aqueous solutions using a semi-industrial electrochemical cell that contains a boron doped diamond anode and a zirconium cathode. We have performed cyclic voltammetry, chronoamperometry and bulk electrolysis to give the optimization characteristics of the degradation of such a compound and its by-products. Bulk electrolysis in the potential region of electrolyte decomposition leads to the complete destruction of 2,4,5-T and its degradation intermediates by means of the electrogeneration of the highly reactive hydroxyl radicals. The evolution of the chemical oxygen demand (COD and the instant current efficiency (ICE during the degradation process is perfectly predicted by a theoretical mathematical model. HPLC and GC-MS have also been performed to highlight the evolution of the mother product and its degradation intermediates. Kinetic analysis of the obtained results has shown a fast destruction of the mother herbicide asserting a diffusion-controlled process. 2,4,5-trichlorophenol and quinone-based organic compounds have been depicted as aromatic intermediates, all of them transformed into short chains carboxylic acids before complete mineralization happens.

  4. Fumarolic minerals

    DEFF Research Database (Denmark)

    Balic Zunic, Tonci; Garavelli, Anna; Jakobsson, Sveinn Peter

    2016-01-01

    The fumarolic mineralogy of the Icelandic active volcanoes, the Tyrrhenian volcanic belt (Italy) and the Aegean active arc (Greece) is investigated, and literature data surveyed in order to define the characteristics of the European fumarolic systems. They show broad diversity of mineral...... associations, with Vesuvius and Vulcano being also among the world localities richest in mineral species. Volcanic systems, which show recession over a longer period, show fumarolic development from the hightemperature alkaline halide/sulphate, calcic sulphate or sulphidic parageneses, synchronous...... fluctuations in activity, illustrated by the example of Vulcano where the high-temperature association appears intermittently. A full survey of the mineral groups and species is given in respect to their importance and appearance in fumarolic associations....

  5. Which Russia, twenty years later?

    Directory of Open Access Journals (Sweden)

    Carmen Claudín

    2011-12-01

    Full Text Available Russia is proud of its position among the emerging powers, of the strength provided by its ample energetic resources and its nuclear potential with which it can influence the world and always be taken into account. Nevertheless, the perception within the country is that stagnation has become Russia’s dominant characteristic at present. The objective of this article is to explore how this situation came about, analysing the evolution of domestic processes in Russia during both of its most defining periods: Yeltsin and Putin’s leadership, since the ephemeral presidency of Medvedev proved to be basically a continuation of the latter. During the eight years of Boris Yeltsin’s tenure, the state of crisis, latent or open, developed into the way that political processes are carried out in Russia. With Putin’s arrival, however, stability and State control are imposed, against the backdrop of economic growth, and they become values in themselves, far from the democratic discourse of the first years.

  6. Twenty Questions Games Always End With Yes

    CERN Document Server

    Gill, John T

    2010-01-01

    Huffman coding is often presented as the optimal solution to Twenty Questions. However, a caveat is that Twenty Questions games always end with a reply of "Yes," whereas Huffman codewords need not obey this constraint. We bring resolution to this issue, and prove that the average number of questions still lies between H(X) and H(X)+1.

  7. Capital in the Twenty-First Century

    DEFF Research Database (Denmark)

    Hansen, Per H.

    2014-01-01

    Review essay on: Capital in the Twenty-First Century. By Thomas Piketty . Translated by Arthur Goldhammer . Cambridge, Mass.: The Belknap Press of Harvard University Press, 2014. viii + 685 pp......Review essay on: Capital in the Twenty-First Century. By Thomas Piketty . Translated by Arthur Goldhammer . Cambridge, Mass.: The Belknap Press of Harvard University Press, 2014. viii + 685 pp...

  8. Thorium in mineral products.

    Science.gov (United States)

    Collier, D E; Brown, S A; Blagojevic, N; Soldenhoff, K H; Ring, R J

    2001-01-01

    Many ores contain low levels of thorium. When these ores are processed, the associated radioactivity can be found in mineral concentrates, intermediates and final products. There is an incentive for industries to remove radioactivity from mineral products to allow the movement and sale of these materials, both nationally and internationally, without the need for licensing. Control of thorium in various products involves the development and optimisation of process steps to be able to meet product specifications. The Australian Nuclear Science and Technology Organisation (ANSTO) has undertaken a range of R & D programmes targeting the treatment of thorium-bearing minerals. This paper discusses the application of a microprobe technique for siting radioactivity in zircon and ilmenite and the problems experienced in measuring the concentrations in solid rare earth products.

  9. Radioactivity of phosphate mineral products

    OpenAIRE

    Mitrović Branislava; Vitorović Gordana; Stojanović Mirjana; Vitorović Duško

    2011-01-01

    The phosphate industry is one of the biggest polluters of the environment with uranium. Different products are derived after processing phosphoric ore, such as mineral and phosphate fertilizers and phosphate mineral supplements (dicalcium-and monocalcium phosphate) for animal feeding. Phosphate mineral additives used in animal food may contain a high activity of uranium. Research in this study should provide an answer to the extent in which phosphate minera...

  10. Mineral Processing Experimental on a Scheelite Ore in Guangdong Province%广东某白钨矿选矿的试验研究

    Institute of Scientific and Technical Information of China (English)

    李英霞; 王国生

    2012-01-01

    广东某钨矿的主要钨矿物为白钨矿,采用常温粗选—加温精选的浮选工艺回收钨矿物.当原矿品位WO3为0.593%时,以碳酸钠为调整剂,水玻璃为抑制剂,ZL为捕收剂,浮选闭路试验可获得品位W03 65.97%、回收率81.98%的白钨精矿.%The main tungsten mineral is scheelite in a tungsten mine Guangdong. Tungsten minerals are recovered by use of the flotation process of normal temperature roughing and heating cleaning, with Na2CO3 as regulator, sodium silicate as depressant and ZL as collector. A scheelite concentrate containing 65.97% WO3 with a recovery of 81. 98% was obtained, by the closed - circuit flotation test from the run - of - mine containing 0. 593% W03 by the closed - circuit flotation test.

  11. Effect of Domestic Processing Methods on Dry Matter, Total Sugar, Phenolics and Mineral Composition in Different Developmental Stages of Parkia roxburghii G. (Don. Pods

    Directory of Open Access Journals (Sweden)

    Jekendra Singh SALAM

    2013-02-01

    Full Text Available Parkia roxburghii is considered delicious in the Northeastern part of India, especially in the state of Manipur. Though it is widely used, information about the biochemical composition and its changes, after processing, is hardly available. In the present experiment, effect of processing methods on dry matter, soluble sugar, phenolics and mineral composition in different developmental stages of P. roxburghii pods were studied. Total soluble sugar (TSS, total phenols (TP, and orthodihydric phenols (ODHP were determined as per the methods of Morris (1948, Bray and Thorpe (1954 and Mahadevan and Sridhar (1986. Sodium (Na, potassium (K, sulphur (S and phosphorus (P were estimated as per the procedures of Tandon (1993. Calcium (Ca, magnesium (Mg, manganese (Mn, zinc (Zn, iron (Fe, copper (Cu and cobalt (Co were analyzed in an atomic absorption spectrophotometer. Processing methods reduced dry matter, soluble sugar and phenolics in all the stages of the pod. TP and ODHP lost up to the extent of 72.78% in tender stage due to ordinary cooking, while higher loss of ODHP recorded in immature stage of the pod due to pressure cooking. Ca, Mg, K and Zn in different stages were found to be affected significantly by different methods of cooking, while no such changes were observed in case of S, P, Fe, Mn and Cu. The level of iron amongst the micro minerals is appreciably high recording up to 51.0 mg/100 g in the immature stage of the pod. As iron, zinc and manganese are antioxidant micronutrients, their higher presence in P. roxburghii might be of some nutritional importance.

  12. The relationship between various exposure metrics for elongate mineral particles (EMP) in the taconite mining and processing industry.

    Science.gov (United States)

    Hwang, Jooyeon; Ramachandran, Gurumurthy; Raynor, Peter C; Alexander, Bruce H; Mandel, Jeffrey H

    2014-01-01

    Different dimensions of elongate mineral particles (EMP) have been proposed as being relevant to respiratory health end-points such as mesothelioma and lung cancer. In this article, a methodology for converting personal EMP exposures measured using the National Institute for Occupational Safety and Health (NIOSH) 7400/7402 methods to exposures based on other size-based definitions has been proposed and illustrated. Area monitoring for EMP in the taconite mines in Minnesota's Mesabi Iron Range was conducted using a Micro Orifice Uniform Deposit Impactor (MOUDI) size-fractionating sampler. EMP on stages of the MOUDI were counted and sized according to each EMP definition using an indirect-transfer transmission electron microscopy (ISO Method 13794). EMP were identified using energy-dispersive x-ray and electron diffraction analysis. Conversion factors between the EMP counts based on different definitions were estimated using (1) a linear regression model across all locations and (2) a location-specific ratio of the count based on each EMP definition to the NIOSH 7400/7402 count. The highest fractions of EMP concentrations were found for EMP that were 1-3 μm in length and 0.2-0.5 μm in width. Therefore, the current standard NIOSH Method 7400, which only counts EMP >5 μm in length and ≥ 3 in aspect ratio, may underestimate amphibole EMP exposures. At the same time, there was a high degree of correlation between the exposures estimated according to the different size-based metrics. Therefore, the various dimensional definitions probably do not result in different dose-response relationships in epidemiological analyses. Given the high degree of correlation between the various metrics, a result consistent with prior research, a more reasonable metric might be the measurement of all EMP irrespective of size. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the

  13. Characterization and mechanical separation of metals from computer Printed Circuit Boards (PCBs) based on mineral processing methods.

    Science.gov (United States)

    Sarvar, Mojtaba; Salarirad, Mohammad Mehdi; Shabani, Mohammad Amin

    2015-11-01

    In this paper, a novel mechanical process is proposed for enriching metal content of computer Printed Circuit Boards (PCBs). The PCBs are crushed and divided into three different size fractions namely: -0.59, +0.59 to 1.68 and +1.68 mm. Wet jigging and froth flotation methods are selected for metal enrichment. The coarse size fraction (+1.68 mm) is processed by jigging. The plastic free product is grinded and screened. The oversized product is separated as the first concentrate. It was rich of metal because the grinding process was selective. The undersized product is processed by froth flotation. Based on the obtained results, the middle size fraction (+0.59 to 1.68 mm) and the small size fraction (-0.59 mm) are processed by wet jigging and froth flotation respectively. The wet jigging process is optimized by investigating the effect of pulsation frequency and water flow rate. The results of examining the effect of particle size, solid to liquid ratio, conditioning time and using apolar collector showed that collectorless flotation is a promising method for separating nonmetals of PCBs. 95.6%, 97.5% and 85% of metal content of coarse size, middle size and small size fraction are recovered. The grades of obtained concentrates were 63.3%, 92.5% and 75% respectively. The total recovery is calculated as 95.64% and the grade of the final concentrate was 71.26%. Determining the grade of copper and gold in the final product reveals that 4.95% of copper and 24.46% of gold are lost during the concentration. The major part of the lost gold is accumulated in froth flotation tail. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. 云南某氧化锰矿选矿试验研究%Mineral processing research for manganese oxide ores from Yunnan

    Institute of Scientific and Technical Information of China (English)

    李宁钧; 兰健; 梁怀文

    2014-01-01

    云南某氧化锰矿属于半风化型沉积锰矿,原矿锰品位16.17%,选矿试验研究表明:采用“洗矿-跳汰-跳汰尾矿强磁选”选矿工艺流程,锰总回收率达到了92.26%,选别指标理想。%Manganese oxide ores from Yunnan is part of semi weathering type of sedimentary manganese oxide ores;the raw ores contains 16.17%manganese. The test results show that the mineral processing flow sheet was carried out by washed ore-jigging-high intensity magnetic separation of jigging tailing can achieve good dressing index of the recovery 0f manganese is 92.26%in total.

  15. Inoculation experimental animals with Paracoccidioides brasiliensis strains: an attempt to reestablish the dimorphic process and variation in pathogenicity as a function of time of preservation under mineral oil.

    Science.gov (United States)

    Mendes da Silva, A M; Borba, C M; de Oliveira, P C

    1996-01-01

    In an attempt to reestablish the dimorphic process in strains of Paracoccidioides brasiliensis in the transition phase (Y reversible M) and to reisolate them, five strains in the transitional phase due to the long time of preservation under mineral oil and two strains in the yeast-like phase were inoculated into male albino rats. The animals were then studied for the presence of paracoccidioidomycotic granulomata. Of the seven strains inoculated, five caused granulomatous nodules in several organs of the animals and only two of these five strains, which had been preserved for the shortest period of time (9 years) were reisolated in culture. Two strains were unable to provoke infection, with no lesions detected in any organ. It is assumed that the long period of time during which the strains were left under oil favored the alteration of celt wall contents, leading to differences in pathogenicity.

  16. [Evaluating exposure of population to dust, with consideration of components and dispersion contents of industrial discharges from enterprise extracting and processing mineral raw materials (discussion)].

    Science.gov (United States)

    Mai, I V; Zagorodnov, S Iu; Popova, E V

    2014-01-01

    The article covers results of study concerning disperse content of solid components of discharges from main dust- generating technologic operations in extraction and processing of mineral raw materials (pouring ore to conveyor, drying with combustion gas in fluid-bed, pouring of end product, sorting ore on riddle, drying on vibration dry and cool device, etc). Findings are that fractions under 10 and 2.5 micrometers approach 50% in general structure of dust discharges. Maximal share of low-disperse dust enters ambient air from vibraion dry and cool devices, riddles and pouring places. Exceeded reference values for acute and chronic exposure are registered on TSP and PM10 at a sanitary protection zone border and in the nearest living area points--that can forecast intolerable risks for health of population exposed and necessitate instrumental confirmation of the detected jeopardy level.

  17. 某细粒浸染铜锌矿选矿工艺研究%The Mineral Processing Technology forone Fine-grained Disseminated Copper-zinc Ore

    Institute of Scientific and Technical Information of China (English)

    何晋勇; 陆长龙; 肖骏

    2016-01-01

    The mineral processing technology investigation is conducted on one fine-grained disseminated copper-zinc ore in Yunnan. The sulphide minerals have a complex metasomatic embedded relationship in this copper-zinc ore. The mineral processing flow that copper differential flotation, regrinding of copper rough concentrate, activation flotation of zinc from copper tailings is adopted, which improved the single separation degree of fine-grained disseminated and embedded copper pyrites and sphalerite. Meanwhile, by using BP+ ethyl xanthogenate as the collecting agent of copper ore, Na2S+Na2SO3+ZnSO4 as the combined depressants of zinc ore, therefore the effective separation between fine-grained disseminated copper-zinc ore was achieved. Under the conditions that in the raw ore, copper content is 0.82%, zinc content is 2.21%, we can get the indexes that copper concentrate with Cu 20.92%, Zn 2.89%, the recovery rate of Cu is 87.41% in the copper concentrate, the Cu content is 1.24% in zinc concentrate, The Zn recovery rate is 89.15% in the zinc concentrate.%针对云南某细粒浸染铜锌矿开展了选矿工艺研究.该铜锌矿中的硫化矿物具有复杂的交代嵌生关系,本研究采用优先浮铜-铜粗精矿再磨-铜尾矿活化浮选锌的工艺流程,提高了细粒浸染交代嵌生的黄铜矿、闪锌矿的单体解离度.同时,使用BP+乙黄药做铜矿物的组合捕收剂, Na2S+Na2SO3+ZnSO4做锌矿物组合抑制剂,实现了细粒浸染铜锌矿的有效分离.在原矿含铜0.82%、锌2.21%的情况下,获得了铜精矿含Cu 20.92%、Zn 2.89%,铜精矿中Cu回收率87.41%,锌精矿含Cu 1.24%、Zn 43.34%,锌精矿中Zn回收率89.15%的指标.

  18. Characterization of manganese phases in mineral processing products of the Azul Mine, Carajas. Metallurgical implications; Caracterizacao de fases manganesiferas em produtos de beneficiamento da Mina do Azul, Carajas. Implicacoes metalurgicas

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, G.; Fernandez, O.J.Ch., E-mail: pereiragilcimar@hotmail.co, E-mail: ochoque.fernandez@gmail.co [Instituto Federal de Ciencia e Tecnologia do Para (IFPA), Belem, PA (Brazil). Curso de Engenharia de Materiais; Costa, M.L. da, E-mail: mlc@ufpa.b [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Geociencias

    2010-07-01

    Were characterized the manganese phases of the processing products using ore microscopy and x-ray diffraction, in order to contribute with new data and help the processing operations of the mine. Cryptomelane is the main manganese mineral in products, and pyrolusite and nsutite are in minor proportion. Were observed distinctive textures of the cryptomelane and others manganese phases, it were formed in different geological times and therefore affecting the operations in mineral processing, principally, comminution. The observed mineralogical variations affect too the unit operations when expand the pit. (author)

  19. Cloud processing of mineral dust: direct comparison of cloud residual and clear sky particles during AMMA aircraft campaign in summer 2006

    Directory of Open Access Journals (Sweden)

    A. Matsuki

    2010-02-01

    Full Text Available In order to gain insights into the characteristics of the mineral dust particles incorporated in the actual cloud droplets and the related cloud processing, the French ATR-42 research aircraft equipped both with a counterflow virtual impactor (CVI and community aerosol inlet was deployed in Niamey, Niger (13°30' N, 02°05' E in August 2006 within the framework of the African Monsoon Multidisciplinary Analysis (AMMA project.

    Cloud residual and clear-sky particles were collected separately and analyzed individually using a transmission electron microscope (TEM and a scanning electron microscope coupled with an energy dispersive X-ray spectroscopy (SEM-EDX. The analysis revealed interesting characteristics on the coarse dust particles (Dp>1μm, particularly those which likely had acted as CCN.

    Traces of heterogeneously formed secondary sulfate, chloride and nitrate were found on many dust particles (though fraction of sulfate may be present in the form of gypsum as primary dust component. These secondary species were particularly enhanced in clouds (i.e. cloud processing. The study illustrates that calcium-rich particles assumed to be carbonates (Calcite, Dolomite contained the secondary species in significantly larger frequency and amount than the silicates (Quartz, Feldspar, Mica, Clay, suggesting that they represent the most reactive fraction of the mineral dust. A surprisingly large fraction of the Ca-rich particles were already found in deliquesced form even in clear-sky conditions, most probably reflecting their extreme hygroscopicity, resulting from their reaction with HNO3 gas.

    Both silicate and Ca-rich particles were found dominant among the supermicron cloud residues, and they were supposed to be those previously activated as CCN. It is highly probable that the observed formation of soluble materials enhanced their cloud nucleating abilities.

  20. A new fluorescent film sensor for Pb(II) ions developed by simulating bio-mineralization process synthesizing of ZnS/CS nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Wang Shan, E-mail: shanwang2005@163.com [School of Chemistry and Chemical Engineering, Xianyang Normal University, Xianyang, 712000, Shaanxi Province (China) and Department of Applied Chemistry, Xi' an Jiaotong University, Xi' an, 710049, Shaanxi Province (China); Yu Demei; Wu Guangwen [Department of Applied Chemistry, Xi' an Jiaotong University, Xi' an, 710049, Shaanxi Province (China); Guo Jinchan; Lei Cao [School of Chemistry and Chemical Engineering, Xianyang Normal University, Xianyang, 712000, Shaanxi Province (China)

    2011-07-25

    Highlights: > Chitosan/zinc sulfide (CS/ZnS) nano-composite films have been prepared by simulating bio-mineralization process.the sensing properties of nano-composite films to lead ions have been systematically investigated. > SEM and TEM observations showed that the size of ZnS particles in the CS films. > The fluorescence emission of the nanocomposite films is very sensitive to the presence of Pb ions and the emission is hardly affected by common ions in water, except for the iron ions. > The films may be developed as excellent sensing films for Pb ions in water. - Abstract: Chitosan/zinc sulfide (CS/ZnS) nano-composite films have been prepared by simulating bio-mineralization process. Factors affecting the hydrothermal stability and fluorescence properties of the films have been studied. Furthermore, the sensing properties of nano-composite films to lead ions have been systematically investigated. SEM and TEM observations showed that the size of ZnS particles is 70 nm, and the particles are evenly distributed within the CS films. The fluorescence emission of the nano-composite films indicates that the sizes of real fluorescing ZnS particles are less than 20 nm. This suggests that ZnS particles observed via SEM and TEM may be aggregates of smaller ZnS particles, and the smaller particles may be separated by the organics. The fluorescence emission (363 nm) of the nano-composite films is very sensitive to the presence of Pb ions. C{sub (Pb}{sup 2+}{sub )} increased from 0 to 664.2 mg L{sup -1} increases the emission dramatically. The emission is hardly affected by common ions in water, except for the iron ions. The films may be developed as excellent sensing films for Pb ions in water.

  1. 75 FR 80947 - Conflict Minerals

    Science.gov (United States)

    2010-12-23

    ... violence in the eastern Democratic Republic of the Congo, particularly sexual- and gender-based violence... conflict free,'' the facilities used to process the conflict minerals, the country of origin of the conflict minerals, and ``the efforts to determine the mine or location of origin with the greatest...

  2. The nature of gold in the Aitik Cu-Au deposit:implications for mineral processing and mine planning

    OpenAIRE

    Sammelin, Monika

    2011-01-01

    The Aitik mine is a large Cu-Au producer in Europe with an annual production of 28 million tons of ore and a planned expansion of production to 36 million tons of ore until year 2013. Large ongoing investments are done in the mine and a new processing plant is built to manage the capacity increase. The mine is situated 15 kilometers from the town Gällivare, in northern Norrbotten, Sweden. The ore is a large porphyry type deposit with low grades of disseminated copper (0,27 %) and gold (0,16 p...

  3. 低碳经济与选矿行业深化发展关系的思考%Thinks on relationship between low carbon economy and further development of mineral processing industry

    Institute of Scientific and Technical Information of China (English)

    童雄; 罗溪梅

    2011-01-01

    The concept of low carbon economy is introduced, and the necessity of propelling low carbon economy in mineral processing industry is general analyzed. In addition, it is indicated that to comprehensively utilize tailings, enhance concentrate grade, develop new-type equipments and optimize mineral processing technologies etc. are necessary measures to propel low carbon economy and promote the sustainable development of the mineral processing industry.%介绍了低碳经济的概念,浅析选矿行业推行低碳经济的必要性,指出综合利用尾矿、提高选矿品位、研发新型设备以及优化选矿工艺等是推行低碳经济、促进选矿行业可持续发展的必要措施。

  4. CO2 + N2O mixture gas hydrate formation kinetics and effect of soil minerals on mixture-gas hydrate formation process

    Science.gov (United States)

    Enkh-Amgalan, T.; Kyung, D.; Lee, W.

    2012-12-01

    CO2 mitigation is one of the most pressing global scientific topics in last 30 years. Nitrous oxide (N2O) is one of the main greenhouse gases (GHGs) defined by the Kyoto Protocol and its global warming potential (GWP) of one metric ton is equivalent to 310 metric tons of CO2. They have similar physical and chemical properties and therefore, mixture-gas (50% CO2 + 50% N2O) hydrate formation process was studied experimentally and computationally. There were no significant research to reduce N20 gas and we tried to make hydrate to mitigate N20 and CO2 in same time. Mixture gas hydrate formation periods were approximately two times faster than pure N2O hydrate formation kinetic in general. The fastest induction time of mixture-gas hydrate formation observed in Illite and Quartz among various soil mineral suspensions. It was also observed that hydrate formation kinetic was faster with clay mineral suspensions such as Nontronite, Sphalerite and Montmorillonite. Temperature and pressure change were not significant on hydrate formation kinetic; however, induction time can be significantly affected by various chemical species forming under the different suspension pHs. The distribution of chemical species in each mineral suspension was estimated by a chemical equilibrium model, PHREEQC, and used for the identification of hydrate formation characteristics in the suspensions. With the experimental limitations, a study on the molecular scale modeling has a great importance for the prediction of phase behavior of the gas hydrates. We have also performed molecular dynamics computer simulations on N2O and CO2 hydrate structures to estimate the residual free energy of two-phase (hydrate cage and guest molecule) at three different temperature ranges of 260K, 273K, and 280K. The calculation result implies that N2O hydrates are thermodynamically stable at real-world gas hydrate existing condition within given temperature and pressure. This phenomenon proves that mixture-gas could be

  5. 青海某镍多金属矿选矿试验研究%Mineral processing of nicke polymetallic ore of Qinghai

    Institute of Scientific and Technical Information of China (English)

    胡志凯

    2015-01-01

    Studied at the nickel polymetallic ore of Qinghai,it contains 0.80% nickel,0.2% copper and 0.025%cobalt,that is a typical primary sulfide ore.The main copper mineral is chalcopyrite,pentlandite is the dominant nickel mineral,cobalt exist in pentlandite as isomorphism.The main gangue mineral is tremolite,talc and pyroxene.Process of tacle-copper nickel iso-flotation and nickel flotation was adopted. According to the closed circuit tests,copper concentration contains 25.15% copper,1.23% nickel at a 62.14% copper recover,meantime,nickel concentration contains 0.4% copper,0.24% cobalt and,7.95%nickel at a 80.67% nickel recovery and 75.76%cobalt recovery.%本文针对青海省某铜镍钴多金属矿进行选矿实验研究,该矿为原生硫化矿,原矿中的镍、铜、钴的含量分别为0.80%、0.20%、0.025%,铜矿物主要为黄铜矿,镍矿物主要为镍黄铁矿,钴以类质同象形式赋存在镍黄铁矿中,非金属矿物主要为透闪石、滑石、辉石。采用以铜为主的滑石-铜镍等可浮-尾矿强化回收镍工艺流程,闭路试验指标,铜精矿含铜25.15%,含镍1.23%,铜回收率62.14%;镍精矿含镍7.95%,含铜0.40%,含钴0.24%,镍回收率80.67%,钴回收率75.76%。

  6. The decolorization and mineralization of Acid Orange 6 azo dye in aqueous solution by advanced oxidation processes: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Hsing, H.-J. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China); Chiang, P.-C. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China)]. E-mail: pcchiang@ntu.edu.tw; Chang, E.-E. [Department of Biochemistry, Taipei Medical University, 25 Wu-Shin Street, Taipei 106, Taiwan (China); Chen, M.-Y. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China)

    2007-03-06

    The comparison of different advanced oxidation processes (AOPs), i.e. ultraviolet (UV)/TiO{sub 2}, O{sub 3}, O{sub 3}/UV, O{sub 3}/UV/TiO{sub 2}, Fenton and electrocoagulation (EC), is of interest to determine the best removal performance for the destruction of the target compound in an Acid Orange 6 (AO6) solution, exploring the most efficient experimental conditions as well; on the other hand, the results may provide baseline information of the combination of different AOPs in treating industrial wastewater. The following conclusions can be drawn: (1) in the effects of individual and combined ozonation and photocatalytic UV irradiation, both O{sub 3}/UV and O{sub 3}/UV/TiO{sub 2} processes exhibit remarkable TOC removal capability that can achieve a 65% removal efficiency at pH 7 and O{sub 3} dose = 45 mg/L; (2) the optimum pH and ratio of [H{sub 2}O{sub 2}]/[Fe{sup 2+}] found for the Fenton process, are pH 4 and [H{sub 2}O{sub 2}]/[Fe{sup 2+}] = 6.58. The optimum [H{sub 2}O{sub 2}] and [Fe{sup 2+}] under the same HF value are 58.82 and 8.93 mM, respectively; (3) the optimum applied voltage found in the EC experiment is 80 V, and the initial pH will affect the AO6 and TOC removal rates in that acidic conditions may be favorable for a higher removal rate; (4) the AO6 decolorization rate ranking was obtained in the order of O{sub 3} < O{sub 3}/UV = O{sub 3}/UV/TiO{sub 2} < EC < Fenton; (5) the ranking of TOC removal efficiency of selected AOPs was in the order of O{sub 3} = Fenton < EC < O{sub 3}/UV < O{sub 3}/UV/TiO{sub 2} for 30 min of reaction time.

  7. Ultrafine particles derived from mineral processing: A case study of the Pb-Zn sulfide ore with emphasis on lead-bearing colloids.

    Science.gov (United States)

    Mikhlin, Yuri; Vorobyev, Sergey; Romanchenko, Alexander; Karasev, Sergey; Karacharov, Anton; Zharkov, Sergey

    2016-03-01

    Although mining and mineral processing industry is a vast source of heavy metal pollutants, the formation and behavior of micrometer- and nanometer-sized particles and their aqueous colloids entered the environment from the technological media has received insufficient attention to date. Here, the yield and characteristics of ultrafine mineral entities produced by routine grinding of the Pb-Zn sulfide ore (Gorevskoe ore deposit, Russia) were studied using laser diffraction analysis (LDA), dynamic light scattering (DLS) and zeta potential measurement, microscopy, X-ray photoelectron spectroscopy, with most attention given to toxic lead species. It was revealed, in particular, that the fraction of particles less that 1 μm in the ground ore typical reaches 0.4 vol. %. The aquatic particles in supernatants were micrometer size aggregates with increased content of zinc, sulfur, calcium as compared with the bulk ore concentrations. The hydrodynamic diameter of the colloidal species decreased with time, with their zeta potentials remaining about -12 mV. The colloids produced from galena were composed of 20-50 nm PbS nanoparticles associated with lead sulfate and thiosulfate, while the surface oxidation products at precipitated galena were largely lead oxyhydroxides. The size and zeta potential of the lead-bearing colloids decreased with time down to about 100 nm and from -15 mV to -30 mV, respectively. And, conversely, lead sulfide nanoparticles were mobilized before the aggregates during redispersion of the precipitates in fresh portions of water. The potential environmental impact of the metal-bearing colloids, which is due to the large-scale production and relative stability, is discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. "PROCESS and UVolution: photochemistry experiments in Low Earth Orbit": investigation of the photostability of organic and mineral material exposed to Mars surface UV radiation conditions

    Science.gov (United States)

    Stalport, Fabien; Guan, Yuan Yong; Noblet, Audrey; Coll, Patrice; Szopa, Cyril; Macari, Frederique; Person, Alain; Chaput, Didier; Raulin, Francois; Cottin, Hervé

    The harsh martian environment could explain the lack of organics and minerals such as car-bonates by destroying them: i) no organic molecule has been found at the two different landing sites of the Viking landers within the detection limits of the instruments onboard, ii) to date, no large deposits of carbonates have been detected and their detection is specific of local ar-eas and in very low amounts. In this context several experimental and numerical modelling studies were led to evaluate the possibility for the destruction or evolution of the organics and carbonates under the martian surface environmental conditions. The presence of UV radiation has been proposed to explain the photodecomposition of such material. This is the reason why, to investigate the nature, abundance, and stability of organic and mineral material that could survive under such environmental conditions, we exposed in low Earth orbit organic molecules and carbonates (also biominerals) with martian relevance to solar UV radiation ¿ 200 nm, in the frame of the experiment UVolution, onboard the BIOPAN ESA module which was set outside a Russian Foton automated capsule and exposed to space condition during 12 days in September 2007, and the experiment PROCESS (hervé peux tu rajouter quelques infos sur le temps exact d'exposition stp) which was set outside the International Space Station (ISS). Here, we present results with regard to the impact of solar UV radiation on the targeted molecules. Preliminary results indicate that that no organic sample seems to resist to the solar UV radiation if directly exposed to it. Conversely our results show that the exposed carbonates seem to be stable to the solar UV radiation if directly exposed to it. Moreover, the stability of the biominerals strengthens the interest to explore deeper their potential as life records at Mars. Hence they should be considered as primary targets for in situ analyses during future missions.

  9. Environmental sustainability of the solar photo-Fenton process for wastewater treatment and pharmaceuticals mineralization at semi-industrial scale.

    Science.gov (United States)

    Foteinis, Spyros; Monteagudo, Jose Maria; Durán, Antonio; Chatzisymeon, Efthalia

    2017-08-31

    The environmental sustainability of a semi-industrial solar photo-Fenton reactor, treating real effluents emanating from a pharmaceutical laboratory, is assessed herein. The life cycle assessment/analysis (LCA) methodology was employed and real life cycle inventory (LCI) data was collected from a ferrioxalate-assisted homogeneous solar photo-Fenton wastewater treatment plant (WWTP), at Ciudad Real, Spain. Electricity was provided by photovoltaic (PV) panels in tandem with a battery bank, making the plant autonomous from the local grid. The effective treatment of 1m(3) of secondary-treated pharmaceutical wastewater, containing antipyrine, was used as a functional unit. The main environmental hotspot was identified to be the chemical reagents used to enhance treatment efficiency, mainly hydrogen peroxide (H2O2) and to a smaller degree oxalic acid. On the other hand, land use, PV panels, battery units, compound parabolic collectors (CPC), tanks, pipes and pumps, as materials, had a low contribution, ranging from as little as 0.06% up to about 2% on the total CO2eq emissions. Overall, the solar photo-Fenton process was found to be a sustainable technology for treating wastewater containing micropollutants at semi-industrial level, since the total environmental footprint was found to be 2.71kgCO2m(-3) or 272mPtm(-3), using IPCC 2013 and ReCiPe impact assessment methods, respectively. A sensitivity analysis revealed that if the excess of solar power is fed back into the grid then the total environmental footprint is reduced. Depending on the amount of solar power fed back into the grid the process could have a near zero total environmental footprint. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Productive practice and technology optimization of mineral processing for copper-nickel ore in Hami%哈密铜镍矿选矿工艺优化与生产实践

    Institute of Scientific and Technical Information of China (English)

    罗立群; 李金良; 黄红

    2014-01-01

    fine mud is easy to come into being while being process and deteriorate separation environments ,grinding fineness about 78 percent should be appropriate .It was successfully that high modulus of sodium silicate (modulus 3 .1) instead of sodium hexametaphosphate and sodium silicate (modulus 2 .7) strengthened dispersion of slurry ,degree of etherification of methyl-isobutyl-carbinol (M IBC ) enhanced depression of talc and high magnesium oxide minerals as well as synergistic effect was reinforced in addition to a part of new collector Y 89-2 and cancalled foaming agent BK-204 .Production stability ,economic and technical indicators ia good and economic benefitsof over twenty one million seven hundred twenty thousand yuan are gained after productive renovation .

  11. Effect of sprouting and roasting processes on some physico-chemical properties and mineral contents of soybean seed and oils.

    Science.gov (United States)

    Özcan, Mehmet Musa; Al Juhaimi, Fahad

    2014-07-01

    Free fatty acid contents of sprouted soybean oil were found between 1.26% (Adasoy) and 4.20% (Nazlıcan and Türksoy). Peroxide values (PV) of sprouted soybean oils were found between 1.52meq/kg (Adasoy) and 3.85meq/kg (A3935), while peroxide values of roasted seed oils were determined between 2.52meq/kg (Adasoy) and 4.03meq/kg (Nova). Palmitic, oleic and linoleic acids were found as major fatty acids of soybean genotypes. Oleic acid contents of samples were found between 19.07% (roasted Adasoy) and 35.31% (roasted A3935), linoleic contents of oils ranged between 42.17% (roasted Nazlican) and 54.76% (sprouted A3127). Macro and micro element contents of sprouted, oven roasted and raw (untreated) soybean seeds were determined by Inductively Coupled Plasma Atomic Emission Spectrometry. The potassium contents of soybean seeds ranged between 16,375mg/kg (raw Adasoy) and 20,357mg/kg (sprouted A3127, while phosphorus contents of seeds varied from 5427mg/kg (oven roasted Türksoy) to 7759mg/kg (sprouted Nova). The micro element contents of samples were found to be different depending on the processing procedures and soybean genotypes.

  12. Mineral processing and characterization of coal waste to be used as fine aggregates for concrete paving blocks

    Directory of Open Access Journals (Sweden)

    C. R. Santos

    Full Text Available Commercial coal production in the southern region of Brazil has been occurring since the beginning of the twentieth century. Due to the geological characteristics of the region, large amounts of solid wastes are generated. The aim of this work was to evaluate the use of coal waste to produce concrete paving blocks. A procedure to process the coal waste with the purpose of reducing the sulfur content and changing the particle size distribution of the material to meet the specification of fine aggregates was developed. The methodology considered the following steps: (a sampling of a coal mining waste; (b gravity separation of the fraction with specific gravity between 2.4 and 2.8; (c comminution of the material and particle size analysis; (d technological characterization of the material and production of concrete paving blocks; and (e acidity generation prediction (environmental feasibility. The results showed that the coal waste considered in this work can be used to replace conventional sand as a fine aggregate for concrete paving blocks in a proportion of up to 50%. This practice can result in cleaner coal production and reduce the demand for exploitation of sand deposits.

  13. Increased Prevalence of Dental Fluorosis after Twenty Years

    DEFF Research Database (Denmark)

    Richards, Alan; Larsen, Mogens Joost; Maare, L.

    2006-01-01

    children, of similar ages, examined in the same area in 1984. Results: The prevalence and severity of fluorosis varied between tooth types so that the later in childhood the teeth are mineralized the higher the prevalence of dental fluorosis. When the data were compared to those collected 20 years...... in the (later formed) premolars and second molars. Conclusions: A significant increase in fluorosis prevalence has occurred over the last 20 years due to increased fluoride exposure of pre-school children. These findings may be explained by increased use of fluoride toothpaste by this age group from......0977   Increased Prevalence of Dental Fluorosis after Twenty Years A. RICHARDS1, M. LARSEN1, L. MAARE2, and H. HEDEBOE2, 1Aarhus University, Faculty of Health Sciences, Denmark, 2Præstø School Dental Service, Denmark Objectives: To describe the prevalence and severity of dental fluorosis among all...

  14. Microbially mediated mineral carbonation

    Science.gov (United States)

    Power, I. M.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2010-12-01

    Mineral carbonation involves silicate dissolution and carbonate precipitation, which are both natural processes that microorganisms are able to mediate in near surface environments (Ferris et al., 1994; Eq. 1). (Ca,Mg)SiO3 + 2H2CO3 + H2O → (Ca,Mg)CO3 + H2O + H4SiO4 + O2 (1) Cyanobacteria are photoautotrophs with cell surface characteristics and metabolic processes involving inorganic carbon that can induce carbonate precipitation. This occurs partly by concentrating cations within their net-negative cell envelope and through the alkalinization of their microenvironment (Thompson & Ferris, 1990). Regions with mafic and ultramafic bedrock, such as near Atlin, British Columbia, Canada, represent the best potential sources of feedstocks for mineral carbonation. The hydromagnesite playas near Atlin are a natural biogeochemical model for the carbonation of magnesium silicate minerals (Power et al., 2009). Field-based studies at Atlin and corroborating laboratory experiments demonstrate the ability of a microbial consortium dominated by filamentous cyanobacteria to induce the precipitation of carbonate minerals. Phototrophic microbes, such as cyanobacteria, have been proposed as a means for producing biodiesel and other value added products because of their efficiency as solar collectors and low requirement for valuable, cultivable land in comparison to crops (Dismukes et al., 2008). Carbonate precipitation and biomass production could be facilitated using specifically designed ponds to collect waters rich in dissolved cations (e.g., Mg2+ and Ca2+), which would allow for evapoconcentration and provide an appropriate environment for growth of cyanobacteria. Microbially mediated carbonate precipitation does not require large quantities of energy or chemicals needed for industrial systems that have been proposed for rapid carbon capture and storage via mineral carbonation (e.g., Lackner et al., 1995). Therefore, this biogeochemical approach may represent a readily

  15. Bioleaching of Minerals

    Energy Technology Data Exchange (ETDEWEB)

    F. Roberto

    2002-02-01

    Bioleaching is the term used to describe the microbial dissolution of metals from minerals. The commercial bioleaching of metals, particularly those hosted in sulfide minerals, is supported by the technical disciplines of biohydrometallurgy, hydrometallurgy, pyrometallurgy, chemistry, electrochemistry, and chemical engineering. The study of the natural weathering of these same minerals, above and below ground, is also linked to the fields of geomicrobiology and biogeochemistry. Studies of abandoned and disused mines indicate that the alterations of the natural environment due to man's activities leave as remnants microbiological activity that continues the biologically mediated release of metals from the host rock (acid rock drainage; ARD). A significant fraction of the world's copper, gold and uranium is now recovered by exploiting native or introduced microbial communities. While some members of these unique communities have been extensively studied for the past 50 years, our knowledge of the composition of these communities, and the function of the individual species present remains relatively limited. Nevertheless, bioleaching represents a major strategy in mineral resource recovery whose importance will increase as ore reserves decline in quality, become more difficult to process (due to increased depth, increased need for comminution, for example), and as environmental considerations eliminate traditional physical processes such as smelting, which have served the mining industry for hundreds of years.

  16. Mineral Processing Experiment on Copper Smelting Slag%某铜冶炼渣铜选矿试验研究

    Institute of Scientific and Technical Information of China (English)

    陈杜娟; 李福兰

    2016-01-01

    针对甘肃某公司所属的铜冶炼渣成分复杂、嵌布粒度不均匀的性质特点采用优先快速浮选出一部分易浮铜矿物得到合格的铜精矿1,优先浮选尾矿经一次粗选、三次精选、一次扫选获得合格的铜精矿2,一次精选中矿及扫选中矿返回球磨机再磨的工艺流程,铜粗选二采用针对该铜冶炼渣性质研制的新型捕收起泡剂酯-11,闭路试验获得了铜品位为29.69%,铜回收率为85.62%的总铜精矿,试验指标良好,为现场工艺改进提供了技术依据。%In view of the characteristic of composition complex, uneven disseminated extent of copper smelting slag in a Gansu enterprise, the following flowsheet was adopted:a part of copper content of easy floatation was floated with rapid se⁃lective⁃flotation to acquire copper concentrate 1, then the qualified copper concentrate. 2 was acquired by once roughing, triple refined concentration and once scavenging from the preferential flotation tailings, the middings of once concentrating and scavenging was returned to ball mill. The new collecting foaming agent ester⁃11 which was developed aiming at the char⁃acteristic of this slag was adopted in the second copper roughing. Closed⁃circuit test obtained the total copper content with copper grade 29.69%, copper recovery 85.62%, the indexes was well, which provides technical basis for process improve⁃ment.

  17. Micro-investigation of EPICA Dome C bottom ice: evidence of long term in situ processes involving acid-salt interactions, mineral dust, and organic matter

    Science.gov (United States)

    de Angelis, M.; Tison, J.-L.; Morel-Fourcade, M.-C.; Susini, J.

    2013-10-01

    The EPICA Dome C ice core (EDC) reached a final depth of 3260 m, at a maximum height of about 15 m above the ice-bedrock interface in December 2004. We present here data gained from a detailed investigation of selected samples of the deeper part of the core located below 3200 m and referred to as bottom ice. This part of the core has been poorly investigated so far mainly because there are significant challenges in interpreting paleo-records that were very likely modified by long term in situ processes. Our study combines high resolution ion chromatography, high resolution synchrotron X-Ray micro-fluorescence (micro XRF), scanning, and transmission electron microscopy. Our aim was to identify the long term physico-chemical processes at work close to the bedrock, to determine how they have altered the initial registers, and, ultimately to extract information on the very ancient Antarctic environment. The ubiquitous presence of nanometer iron oxide crystals at the surface of wind-borne dust aggregates containing also large amount of organic matter raises the possibility that the consolidation of windborne dust clusters formed during ice recrystallization could be related to microbial iron reduction and, thus, to the progressive reactivation of dormant bacterial activity in warming ice. Inclusions of size and number density increasing with depth observed in the 12 last meters (3248-3260 m) contain liquid and solid species, among them marine biogenic acids, numerous wind-borne dust aggregates and clusters of large reversible calcium carbonate particles precipitated once the inclusion was formed and often covered by secondary gypsum. The refreezing of slush lenses is discussed as a potential cause of the formation of such heterogeneous and complex mixtures. In addition to the very fine micrometer size minerals windborne from extra-Antarctic continental sources and often accreted in large aggregates, single medium size particles (a few to ca 20 μm and among them organic

  18. Discussion on the Teaching of Concentrator Design for Mineral Processing%矿物加工专业选矿厂设计教学探讨

    Institute of Scientific and Technical Information of China (English)

    陈佳

    2014-01-01

    选矿厂设计是矿物加工专业的一门专业课,课程内容较综合且有很强的应用性。该门课程的学习对于学生毕业后从事选矿及选矿厂设计工作大有益处。目前大部分高校在选矿厂设计教学过程中存在着教学难度较大,教学手段单一,学生实践经验不足等问题。从平时教学过程中,总结了几点提高选矿厂设计教学效果的体会,主要有改进教学方法,丰富教学手段,充分地利用实习机会促进学生对选矿厂设计的理解和认识。%Concentrator Design was a professional course for mineral processing students, with a relatively strong synthetically application, which was beneficial for the students who engaged in the processing of beneficiation and concentrator design after graduation.Most colleges and universities had such problems as great teaching difficulty, backward teaching method and unvaried teaching means, the student lack of practical, etc.Some tips to improve the teaching result were summarized from the process of teaching, such as improving teaching methods, enriching teaching means, and making full use of internship opportunities to promote the students on the basis of the understanding and awareness of the concentrator design.

  19. Atomic Processes on Mineral Surfaces

    Science.gov (United States)

    Hillner, Paul Everett

    This thesis describes research using atomic force microscopy (AFM) to observe the growth and dissolution mechanisms of crystals. Chapter 1 starts with an overview of crystal growth theory and then outlines the impact of AFM on the field. Chapter 2 introduces the techniques of real-time AFM imaging of crystal growth and shows the strong preferential dissolution of material at defects. Chapter 3 expands the importance of crystal defects, showing the importance of spiral defects to the aqueous growth of calcite. Chapter 4 presents a rigorous analysis of step kinetics on calcite and shows that surface diffusion is not the controlling factor of growth rate. Chapter 5 examines the effect of solvent modifications on the growth morphology of spiral hillocks on calcite and also determines the mechanisms by which manmade and natural poisons stop crystal growth. Chapter 6 presents quantitative calcite spiral rotation rates and step velocities vs. supersaturation as well as contrasting the layer-spiral growth mechanism of calcite with the poly -nucleation growth mechanism of fluorite.

  20. Reciclagem de fios e cabos elétricos - cabo paralelo Recycling of parallel wires using unit operations of mineral processing

    Directory of Open Access Journals (Sweden)

    Mishene Christie Pinheiro Bezerra de Araújo

    2008-09-01

    Full Text Available O descarte de produtos eletro-eletrônicos vem crescendo anualmente. Por esse motivo, necessita-se de reciclagem para que se evite o desperdício de recursos naturais não-renováveis. O objetivo desse trabalho é estudar a reciclagem dos cabos tipo cordão paralelo através de operações unitárias de tratamento de minérios. As seguintes operações unitárias foram testadas: moagem, separação granulométrica, separação em meio denso, separação eletrostática, atrição, bateamento e elutriação. Ao final desses processos, observou-se que as operações utilizadas obtiveram concentrados de cobre com baixo grau de contaminação. Observou-se que todas as técnicas precisam de uma outra técnica para complementá-las. Concluiu-se, ainda, que a moagem em moinho de facas com grelha de 3mm é necessária para se conseguir a total liberação dos materiais.The composition and discharge of eletro-electronic products is increasing year after year. To avoid the loss of non-renewable mineral resources and energy, the establishment of a recycling loop for such products is necessary. The goal of this work is to study the recycling of parallel wires using unit operations of mineral processing. The following unit operations were used: grinding, size separation, sink-and-float, electrostatic separation, scrubbing, panning and elutriation. One can observe a low contamination grade in the obtained copper. However, in all cases, a two step flow sheet must be used to completely separate plastics from copper. One can conclude that the total liberation of materials during grinding was reached when the final particle sizes were inferior to 3mm.

  1. Minerals From the Marine Environment

    Science.gov (United States)

    Cruickshank, Michael J.

    The current interest in minerals centering on, among other things, potential shortages, long-term needs, and deep seabed nodules, accentuates the usefulness and timeliness of this little book authored by a former chairman of the British National Environmental Research Council.In less than 100 pages, the author puts into perspective the potential for producing minerals from offshore areas of the world. After introducing the reader to the ocean environment and the extraordinary variety of the nature of the seabed, the author describes in some detail the variety of minerals found there. This is done in seven separate chapters entitled ‘Bulk and Non-Metallic Minerals From the Seas’ ‘Metals From the Shallow Seas’ ‘Metals From the Deep Oceans’ ‘Minerals From Solution’ ‘Oil and Gas from the Shallow Seas’ ‘Oil and Gas From Deep Waters’ and ‘Coal Beneath the Sea.’ The remaining chapters give a brief regional review of marine minerals distribution for eight areas of significant socioeconomic structure, and a short recapitulation of special problems of mineral recovery in the marine environment including such matters as the effect of water motion on mineral processing and of international law on investments. Glossaries of geological periods and technical terms, a short list of references, and an index complete the work.

  2. Twenty-Channel Voice Response System.

    Science.gov (United States)

    1981-06-01

    programs and vocabulary. 0 Telephone Company (TELCO) Switched Lines - provides access to VRS using telephones. * Bell 407C Data Sets - Converts the Touch...from the twenty 407C units. 0 DLII-E - Asynchronous interface to the 11/34 unibus for the VOTRAX unit. * 20 Channel ADPCM Decoder - a specially designed

  3. Educating the Ablest: Twenty Years Later

    Science.gov (United States)

    Culross, Rita R.

    2015-01-01

    This study examines the current lives of thirty-five individuals who participated in high school gifted programs twenty years ago. The research specifically looked at educational attainment and career goals in terms of expressed aspirations in high school, using social media and other Internet sources. Results indicated continued support for the…

  4. Oxygen Extraction from Minerals

    Science.gov (United States)

    Muscatello, Tony

    2017-01-01

    Oxygen, whether used as part of rocket bipropellant or for astronaut life support, is a key consumable for space exploration and commercialization. In Situ Resource Utilization (ISRU) has been proposed many times as a method for making space exploration more cost effective and sustainable. On planetary and asteroid surfaces the presence of minerals in the regolith that contain oxygen is very common, making them a potential oxygen resource. The majority of research and development for oxygen extraction from minerals has been for lunar regolith although this work would generally be applicable to regolith at other locations in space. This presentation will briefly survey the major methods investigated for oxygen extraction from regolith with a focus on the current status of those methods and possible future development pathways. The major oxygen production methods are (1) extraction from lunar ilmenite (FeTiO3) with either hydrogen or carbon monoxide, (2) carbothermal reduction of iron oxides and silicates with methane, and (3) molten regolith electrolysis (MRE) of silicates. Methods (1) and (2) have also been investigated in a two-step process using CO reduction and carbon deposition followed by carbothermal reduction. All three processes have byproducts that could also be used as resources. Hydrogen or carbon monoxide reduction produce iron metal in small amounts that could potentially be used as construction material. Carbothermal reduction also makes iron metal along with silicon metal and a glass with possible applications. MRE produces iron, silicon, aluminum, titanium, and glass, with higher silicon yields than carbothermal reduction. On Mars and possibly on some moons and asteroids, water is present in the form of mineral hydrates, hydroxyl (-OH) groups on minerals, andor water adsorbed on mineral surfaces. Heating of the minerals can liberate the water which can be electrolyzed to provide a source of oxygen as well. The chemistry of these processes, some key

  5. Suitability analysis of fresh-cut vegetable processing for twenty main green capsicum cultivars in China%中国主栽青辣椒品种鲜切加工适宜性评价

    Institute of Scientific and Technical Information of China (English)

    沈月; 高美须; 杨丽; 赵鑫; 陈雪; 王志东; 李淑荣; 王丽

    2016-01-01

    In order to evaluate the suitability for fresh-cut vegetable processing of green capsicum, 20 main cultivars of green capsicum in China were collected and planted in greenhouse, and fruits were picked at the similar maturity level. Seventeen indices of the fruits were measured, which included physical and chemical indices (L*,a* andb *value, sensory evaluation score, product yield ratio, fruit hardness, pulp thickness, moisture content, ratio of sugar to acid, soluble solids, titratable acid), and functional indices (vitamin C content, total phenolics content, DPPH free radical scavenging activity (DPPH value), ferric ion reducing antioxidant power (FRAP value), ABTS+·radical scavenging activity (ABTS value) and beta carotene content). Significance analysis of basic measured data was carried out by SAS 9.2. Main evaluation indices were filtered by correlation analysis, principal component analysis and variable cluster analysis. The weight of main evaluation indices were determined by analytic hierarchy process (AHP). The suitability for fresh-cut vegetable processing of the 20 tested green pepper cultivars was appraised by grey relational degree analysis method. The basic data of 17 indices on 20 green pepper cultivars were measured and analyzed. Results of significance analysis showed that all indices varied from one tested green capsicum cultivar to another one excepted for moisture content, and the 3 indices which had the top coefficient of variation wereb*value, beta carotene content and FRAP value. Among all the tested 20 cultivars, “Longjiao No. 5” had the highest content of vitamin C, “Jingla No. 2” had the highest content of beta carotene and “Jingyanzhoupila” had the strongest antioxidant capacity. Results of correlation analysis showed that fruit hardness had significantly negative correlation with sensory evaluation score and the correlation coefficient was -0.68, however it had positive correlation with soluble solid content and the

  6. Glycine Polymerization on Oxide Minerals

    Science.gov (United States)

    Kitadai, Norio; Oonishi, Hiroyuki; Umemoto, Koichiro; Usui, Tomohiro; Fukushi, Keisuke; Nakashima, Satoru

    2016-07-01

    It has long been suggested that mineral surfaces played an important role in peptide bond formation on the primitive Earth. However, it remains unclear which mineral species was key to the prebiotic processes. This is because great discrepancies exist among the reported catalytic efficiencies of minerals for amino acid polymerizations, owing to mutually different experimental conditions. This study examined polymerization of glycine (Gly) on nine oxide minerals (amorphous silica, quartz, α-alumina and γ-alumina, anatase, rutile, hematite, magnetite, and forsterite) using identical preparation, heating, and analytical procedures. Results showed that a rutile surface is the most effective site for Gly polymerization in terms of both amounts and lengths of Gly polymers synthesized. The catalytic efficiency decreased as rutile > anatase > γ-alumina > forsterite > α- alumina > magnetite > hematite > quartz > amorphous silica. Based on reported molecular-level information for adsorption of Gly on these minerals, polymerization activation was inferred to have arisen from deprotonation of the NH3 + group of adsorbed Gly to the nucleophilic NH2 group, and from withdrawal of electron density from the carboxyl carbon to the surface metal ions. The orientation of adsorbed Gly on minerals is also a factor influencing the Gly reactivity. The examination of Gly-mineral interactions under identical experimental conditions has enabled the direct comparison of various minerals' catalytic efficiencies and has made discussion of polymerization mechanisms and their relative influences possible Further systematic investigations using the approach reported herein (which are expected to be fruitful) combined with future microscopic surface analyses will elucidate the role of minerals in the process of abiotic peptide bond formation.

  7. Twenty Practices of an Entrepreneurial University

    DEFF Research Database (Denmark)

    Gjerding, Allan Næs; Wilderom, Celeste P.M.; Cameron, Shona P.B.;

    2006-01-01

    similarities; especially that entrepreneurship within universities has to be welcomed and facilitated top-down, but organically occurs and develops bottom-up. Implementing entrepreneurship at universities is thus about stimulating a culture of organic intrapreneurship and we provide practical recommendations...... studies twenty organisational practices against which a University's entrepreneurship can be measured. These twenty practices or factors in effect formed the basis for an entrepreneurship audit. During a series of interviews, the extent to which the universities are seen as entrepreneurial...... by the interviewees was surveyed. We showed that the practices have been implemented only to various degrees and rather unsystematically. There are important differences among the universities, to some extent depending on the level of ambition that each university has regarding each practice. There are also important...

  8. Research on backwater of mineral processing at Anning dressing plant%安宁磷矿浮选厂选矿回水试验研究

    Institute of Scientific and Technical Information of China (English)

    赵凤婷

    2011-01-01

    A research on backwater of mineral processing at Anning dressing plant of Yunnan Phosphate Chemical Group.,LTD is carried out to determine the influence factors.The suspended matter content that impacts on grinding operation is 2 000 mg/L, and the calcium ion content that affects flotation operation is 150 mg/L.The wastewater treatment is mainly aimed at removing harmful and residual ions to make those ions content similar to the tap water, so as to avoid influences of impurities to flotation operation.The backwater after well treated returns to flotation operation, and the flotation indexes are similar by using the regular water and the backwater, which has no effects on flotation operation and its following operations.%通过对云磷公司安宁磷矿选矿回水进行试验研究,确定影响磨矿作业的悬浮物量为2 000 mg/L,确定影响浮选作业的钙离子量为150 mg/L.废水处理以消除SO2-4、PO3-4、Ca2+等有害残留离子为主,尽可能确保这三种离子含量与自来水相近,从而避免杂质离子对浮选产生影响.处理后回水返回浮选作业,浮选指标接近清水指标,不影响浮选作业及其后续加工作业.

  9. Intelligence in the Twenty-First Century

    OpenAIRE

    2000-01-01

    The author concludes that the world will most probably remain rife with conflict even in the twenty first century and that the traditional role of intelligence will not only continue but will increase in importance. He characterizes the international situation as being "more of the same historically"; that is, the existence of several different centers of power and mutual conflicts based solely on national interests. In order to protect and promote one's national interests, sovereign states w...

  10. Servicing the twenty-first century

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, D. [DTLR, London (United Kingdom)

    2002-04-01

    Twentieth century governments have committed themselves to the principle of sustainable development. Efforts to fulfil this goal offer an insight into changes in building services provision in the opening decades of the new century. Sustainable development indicators are used to identify possible trends. The analysis also forms the basis for some speculative conjectures as a basis for a research agenda for the twenty-first century. (Author)

  11. Twenty-first century learning in afterschool.

    Science.gov (United States)

    Schwarz, Eric; Stolow, David

    2006-01-01

    Twenty-first century skills increasingly represent the ticket to the middle class. Yet, the authors argue, in-school learning is simply not enough to help students develop these skills. The authors make the case that after-school (or out-of-school) learning programs are emerging as one of the nation's most promising strategies for preparing young people for the workforce and civic life. Most school systems have significant limitations for teaching twenty-first century skills. They have the limits of time: with only six hours per day there is barely enough time to teach even the basic skills, especially for those students starting already behind. They have the limits of structure: typical school buildings and classrooms are not physically set up for innovative learning. They have the limits of inertia and bureaucracy: school systems are notoriously resistant to change. And perhaps most important, they have the limits of priorities: especially with the onset of the No Child Left Behind Act, schools are laserlike in their focus on teaching the basics and therefore have less incentive to incorporate twenty-first century skills. Meanwhile, the authors argue that after-school programs are an untapped resource with three competitive advantages. First, they enable students to work collaboratively in small groups, a setup on which the modern economy will increasingly rely. Second, they are well suited to project-based learning and the development of mastery. Third, they allow students to learn in the real-world contexts that make sense. Yet the after-school sector is fraught with challenges. It lacks focus-Is it child care, public safety, homework tutoring? And it lacks rigorous results. The authors argue that the teaching of twenty-first century skills should become the new organizing principle for afterschool that will propel the field forward and more effectively bridge in-school and out-of-school learning.

  12. Miscellaneous Industrial Mineral Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes miscellaneous industrial minerals operations in the United States. The data represent commodities covered by the Minerals Information Team...

  13. Mineral resource of the month: vermiculite

    Science.gov (United States)

    Tanner, Arnold O.

    2014-01-01

    Vermiculite comprises a group of hydrated, laminar magnesium-aluminum-iron silicate minerals resembling mica. They are secondary minerals, typically altered biotite, iron-rich phlogopite or other micas or clay-like minerals that are themselves sometimes alteration products of amphibole, chlorite, olivine and pyroxene. Vermiculite deposits are associated with volcanic ultramafic rocks rich in magnesium silicate minerals, and flakes of the mineral range in color from black to shades of brown and yellow. The crystal structure of vermiculite contains water molecules, a property that is critical to its processing for common uses.

  14. Fe2O3-loaded activated carbon fiber/polymer materials and their photocatalytic activity for methylene blue mineralization by combined heterogeneous-homogeneous photocatalytic processes

    Science.gov (United States)

    Kadirova, Zukhra C.; Hojamberdiev, Mirabbos; Katsumata, Ken-Ichi; Isobe, Toshihiro; Matsushita, Nobuhiro; Nakajima, Akira; Okada, Kiyoshi

    2017-04-01

    Fe2O3-supported activated carbon felts (Fe-ACFTs) were prepared by impregnating the felts consisted of activated carbon fibers (ACFs) with either polyester fibers (PS-A20) or polyethylene pulp (PE-W15) in Fe(III) nitrate solution and calcination at 250 °C for 1 h. The prepared Fe-ACFTs with 31-35 wt% Fe were characterized by N2-adsorption, scanning electron microscopy, and X-ray diffraction. The Fe-ACFT(PS-A20) samples with 5-31 wt% Fe were microporous with specific surface areas (SBET) ranging from 750 to 150 m2/g, whereas the Fe-ACFT(PE-W15) samples with 2-35 wt% Fe were mesoporous with SBET ranging from 830 to 320 m2/g. The deposition of iron oxide resulted in a decrease in the SBET and methylene blue (MB) adsorption capacity while increasing the photodegradation of MB. The optimum MB degradation conditions included 0.98 mM oxalic acid, pH = 3, 0.02-0.05 mM MB, and 100 mg/L photocatalyst. The negative impact of MB desorption during the photodegradation reaction was more pronounced for mesoporous PE-W15 samples and can be neglected by adding oxalic acid in cyclic experiments. Almost complete and simultaneous mineralization of oxalate and MB was achieved by the combined heterogeneous-homogeneous photocatalytic processes. The leached Fe ions in aqueous solution [Fe3+]f were measured after 60 min for every cycle and found to be about 2 ppm in all four successive cycles. The developed photocatalytic materials have shown good performance even at low content of iron oxide (2-5 wt% Fe-ACFT). Moreover, it is easy to re-impregnate the ACF when the content of iron oxide is reduced during the cyclic process. Thus, low leaching of Fe ions and possibility of cyclic usage are the advantages of the photocatalytic materials developed in this study.

  15. Gross Nitrogen Mineralization in Surface Sediments of the Yangtze Estuary

    OpenAIRE

    Xianbiao Lin; Lijun Hou; Min Liu; Xiaofei Li; Guoyu Yin; Yanling Zheng; Fengyu Deng

    2016-01-01

    Nitrogen mineralization is a key biogeochemical process transforming organic nitrogen to inorganic nitrogen in estuarine and coastal sediments. Although sedimentary nitrogen mineralization is an important internal driver for aquatic eutrophication, few studies have investigated sedimentary nitrogen mineralization in these environments. Sediment-slurry incubation experiments combined with 15N isotope dilution technique were conducted to quantify the potential rates of nitrogen mineralization i...

  16. Mineral resources and geo-engineering

    Directory of Open Access Journals (Sweden)

    Fathi Habashi

    2015-12-01

    Full Text Available Metals used in everyday life are produced from ores occurring in the Earth’s crust. Geological processes are known to concentrate minerals to form ores of economic value. Mineral processing engineers concentrate these ores by mechanical and physico-chemical methods while the extractive metallurgist extracts the metals by chemical means.

  17. Dehydration-induced luminescence in clay minerals

    Science.gov (United States)

    Coyne, L. M.; Lahav, N.; Lawless, J. G.

    1981-01-01

    Reports of triboluminescent phenomena in organic crystalline materials prompted a search for related processes in clay minerals. The reported extensive mechanical distortion produced on freezing and drying of montmorillonite was particularly interesting because of studies of condensation reactions in a wet/dry cycled reaction sequence. The discovery of an unusual luminescent process in several clay minerals is reported and its characteristics are described.

  18. Mineralization of Carbon Dioxide: Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    Romanov, V; Soong, Y; Carney, C; Rush, G; Nielsen, B; O' Connor, W

    2015-01-01

    CCS research has been focused on CO2 storage in geologic formations, with many potential risks. An alternative to conventional geologic storage is carbon mineralization, where CO2 is reacted with metal cations to form carbonate minerals. Mineralization methods can be broadly divided into two categories: in situ and ex situ. In situ mineralization, or mineral trapping, is a component of underground geologic sequestration, in which a portion of the injected CO2 reacts with alkaline rock present in the target formation to form solid carbonate species. In ex situ mineralization, the carbonation reaction occurs above ground, within a separate reactor or industrial process. This literature review is meant to provide an update on the current status of research on CO2 mineralization. 2

  19. Mineral processing test for a fine grain disseminated gold ore from Gansu Province%甘肃某细粒浸染型金矿石选矿试验研究

    Institute of Scientific and Technical Information of China (English)

    靳建平; 向虹; 吴天骄; 万宏民; 齐晓东

    2016-01-01

    甘肃某细粒浸染型金矿石中金主要以包裹金形态存在,且载金矿物黄铁矿与脉石矿物连生关系复杂.针对该矿石的性质,进行了选矿试验研究.其结果表明:在最佳试验条件下,采用阶段磨矿-阶段浮选工艺,可获得金品位30.17 g/t、金回收率81.23%的较好指标;硫精矿经氧化焙烧—氰化浸出,金对原矿的回收率为6.96%,金总回收率达88.19%.%Mineral processing test was carried out for a fine grain disseminated gold ore from Gansu Province.The gold-carrying mineral is pyrite and it is connected with gangue minerals in a complex way.The test results under opti-mal test conditions,a stage grinding-stage flotation process can obtain a gold grade of 30.17 g/t and a gold recovery rate of 81.23 %.Sulfur concentrates go through roasting-cyanide leaching process,the recovery of primary gold ores is 6.96 %and the total recovery rate of gold is 88.19 %.

  20. The characterization of twenty sequenced human genomes.

    Directory of Open Access Journals (Sweden)

    Kimberly Pelak

    2010-09-01

    Full Text Available We present the analysis of twenty human genomes to evaluate the prospects for identifying rare functional variants that contribute to a phenotype of interest. We sequenced at high coverage ten "case" genomes from individuals with severe hemophilia A and ten "control" genomes. We summarize the number of genetic variants emerging from a study of this magnitude, and provide a proof of concept for the identification of rare and highly-penetrant functional variants by confirming that the cause of hemophilia A is easily recognizable in this data set. We also show that the number of novel single nucleotide variants (SNVs discovered per genome seems to stabilize at about 144,000 new variants per genome, after the first 15 individuals have been sequenced. Finally, we find that, on average, each genome carries 165 homozygous protein-truncating or stop loss variants in genes representing a diverse set of pathways.

  1. Marketing mix of chosen Slovak mineral water

    Directory of Open Access Journals (Sweden)

    Juhanová Silvia

    2001-09-01

    Full Text Available Considering its small area, Slovakia abounds in many sources of mineral waters and a considerable amount of them can be used for the commercial utilization. STN 86 8000 divides mineral waters in the natural mineral waters, natural mineral table waters and the natural mineral healing waters. Natural mineral water is, after the present norm, in effect water, which rises from natural trapped sources. This type of water contains more than 1 gram of dissolved substances or 1 gram of dissolved CO 2 in 1 litter. Natural mineral table water is water that, with its chemical composition as well as its physical and sensorial attributes is suitable as a refresher. It contains at least 1 gram of melted CO2 and up to 6 grams of dissolved illiquid substances in 1 litter. The mentioned substances are not characterised by any marked pharmacological effect. Natural mineral healing water is water, which with an eye to its chemical composition and physical properties, have a scientifically demonstrable effects to the human health and it is generally used for healing purposes. In the present contribution, an attention is orientated to the occurrence of listed types of waters in Slovakia, in connection with geological conditions of their circulation and accumulation and especially with possibilities of their use on the Slovak buyer’s market.The marketing mix is a complex of information, which can be regulated. Firms accumulate this information to satisfy a customer. Marketing mix of mineral waters includes information about four variables: product (characteristics of product, quality, packing, design..., prices, advertisement, distribution (the way how to get product to customer. Data listed in the contribution come from the sectional market research, which was performed between December 1st and December 22nd 2000 in twenty groceries in

  2. NATO Advanced Study Institute on Statistical Treatments for Estimation of Mineral and Energy Resources

    CERN Document Server

    Fabbri, A; Sinding-Larsen, R

    1988-01-01

    This volume contains the edited papers prepared by lecturers and participants of the NATO Advanced Study Institute on "Statistical Treatments for Estimation of Mineral and Energy Resources" held at II Ciocco (Lucca), Italy, June 22 - July 4, 1986. During the past twenty years, tremendous efforts have been made to acquire quantitative geoscience information from ore deposits, geochemical, geophys ical and remotely-sensed measurements. In October 1981, a two-day symposium on "Quantitative Resource Evaluation" and a three-day workshop on "Interactive Systems for Multivariate Analysis and Image Processing for Resource Evaluation" were held in Ottawa, jointly sponsored by the Geological Survey of Canada, the International Association for Mathematical Geology, and the International Geological Correlation Programme. Thirty scientists from different countries in Europe and North America were invited to form a forum for the discussion of quantitative methods for mineral and energy resource assessment. Since then, not ...

  3. Calculation and Selection of Driving Power Belt Conveyor in Mineral Processing Plant%选矿厂带式输送机驱动功率的计算及选取

    Institute of Scientific and Technical Information of China (English)

    杨高天

    2014-01-01

    依选矿厂带式输送机特点,简化带式输送机驱动功率计算公式,并依据选矿工艺,选取带式输送机驱动电机功率。%according to the characteristics of the belt conveyor of mineral processing plant , simplified formula of belt con-veyor driving power , and on the basis of ore dressing process , selection of belt conveyor drive motor power .

  4. Insights into the late-stage differentiation processes of the Catalão I carbonatite complex in Brazil: New Sr-Nd and C-O isotopic data in minerals from niobium ores

    Science.gov (United States)

    Oliveira, Ítalo L.; Brod, José A.; Cordeiro, Pedro F. O.; Dantas, Elton L.; Mancini, Luis H.

    2017-03-01

    The Late Cretaceous Catalão I carbonatite complex consists of ultramafic silicate rocks, phoscorites, nelsonites and carbonatites. The latest stages of the evolution of the complex are characterized by several nelsonite (magnetite-apatite rock) and carbonatite dykes, plugs and veins crosscutting earlier alkaline rocks. The interaction between the latter and late-stage carbonatites and/or carbo-hydrothermal fluids, converted the original dunites and bebedourites to metasomatic phlogopitites. Late-stage nelsonites (N1), pseudonelsonites (N2) and various types of dolomite carbonatites (DC) including norsethite-, magnesite- and/or monazite-bearing varieties show significant whole-rock Nd and Sr isotopic variations. To elucidate whether magmatic or metasomatic processes, or both, were responsible for these isotope variations we characterized the Nd and Sr isotope compositions of major mineral phases (i.e. apatite, dolomite, norsethite, pyrochlore and tetraferriphlogopite) in these late-stage rocks. Mineral isotope data recorded the same differences observed between N1 and N2 whole-rocks with N2 minerals showing more enriched isotopic signatures than minerals from N1. Sr isotopic disequilibrium among minerals from N2 pseudonelsonites and spatially related dolomite carbonatite pockets implies formation from batches of carbonate melts with distinct isotopic compositions. A detailed investigation of Nd and Sr isotopes from whole-rocks and minerals suggests that the most evolved rocks of the Catalão I complex probably derive from two different evolution paths. We propose that an earlier magmatic trend (path A) could be explained by several batches of immiscible and/or residual melts derived from carbonated-silicate parental magma (e.g. phlogopite picrite) contaminated with continental crust to a variable extent, in an AFCLI-like process. A second trend (path B) comprises highly variable 143Nd/144Ndi at nearly constant 87Sr/86Sri coupled with high δ18O in carbonates. This

  5. Metallurgical behavior of fine fractions of copper sulfide minerals in a combined process of modified flotation and agitated bio leaching; Respuesta metalurgica de fracciones finas de minerales sulfurados de cobre en un proceso combinado de flotacion modificada y biolixiviacion agitada

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, J. P.; Ipinza, J.; Collao, N.; Ahlborn, G.

    2007-07-01

    The metallurgical behaviour of fine fraction of copper sulfide minerals of Compania Minera Quebrada Blanca S. A. was studied by concentration through flotation in aqueous media modified by alcohol followed by bio leaching of the concentrates. By using a 1% v/v of methanol, the metallurgical recovery of copper reaches 88%, while the iron recovery was 43%, the weight recovery was 18%, which indicates a high selectivity. these concentrates were then bio leached with and without nutrient medium, reaching 80% of copper recovery after 10 and 17 days, respectively. then, it is possible to conclude that this concentration-bio leaching metallurgical process is a promising route for copper recovery from the fine fraction of sulfide minerals. (Author) 24 refs.

  6. The relationship between caves minerals and hypogene speleogenesis along the Cerna Valley (SW Romania)

    Science.gov (United States)

    Onac, B. P.; Sumrall, J.; Tamas, T.; Povara, I.; Veres, D.; Darmiceanu, V.; Lascu, C.

    2009-04-01

    Over 100 caves are known to develop in the Jurassic and Cretaceous limestone that outcrops on both sides of the Cerna Valley in southwestern Romania. High temperature anomalies are rather uncommon in the cave environment; however, in certain caves in the lower part of Cerna Valley one can measure air temperatures as high as 40°C. This situation is due to the presence of thermal water pooling or flowing through the caves or to the hot steam that rises along fractures from deeper thermal water pools. During the long evolution of the thermo-mineral activity along the Cerna Valley interaction has occurred on a wide scale between the cave host rock or/and cave sediments and the ascending hot steam or/and thermal solutions of all types (mainly sulfide-rich). The present work documents the products of these processes and record the occurrence of twenty-four secondary cave minerals (both of primarily or replacement origin) precipitated under particular cave environments. Among these, glauberite, apjonite, halotrichite, pickeringite, rapidcreekite, tamarugite, and darapskite are the most interesting. The mineral samples were investigated by means of X-ray diffraction, electron microprobe, Fourier-transformed infrared spectroscopy, and scanning electron microscope analyses with the scope of linking the cave minerals with possible hypogene speleogenetic processes. The isotopic measurements (δ34S) performed on sulfate speleothems contribute valuable information on both minerals and caves origin. Apart from two minerals (i.e., calcite and gypsum), which were identified in every cave investigated so far, all the others fall into three distinct associations that have resulted from specific reactions under highly particular settings in Diana (sulfate-dominated association), Adam (phosphate-dominated), and Great Sălitrari (sulfate/phosphate/nitrate-rich association) caves. These three remarkable cave occurrences are presented along with morphological features that confirm the

  7. Managing asbestos in Italy: twenty years after the ban.

    Science.gov (United States)

    Silvestri, Stefano

    2012-01-01

    Establishing an asbestos ban is not sufficient to achieve effective primary prevention. Twenty years after the Italian asbestos ban, the residual presence of asbestos-containing materials, estimated to be 80 percent of the quantity existing in 1992, may still be the cause of negative effects to the health of workers and the general population. The so called "asbestos way-out" at this rate of cleaning up, roughly 1 percent per year, is too slow, and new policy to re-discuss the entire process is needed. Encouragement of the owners with tax relief when the substitution of the asbestos roofs is performed with photovoltaic panels, as well as reducing the cost of removal planning local landfills may be the keys to accelerate the cleanup process.

  8. Mineral resources of Australia

    Energy Technology Data Exchange (ETDEWEB)

    Kelsall, D.F.; Woodcock, J.T. (eds.)

    1979-01-01

    The papers presented cover geological, geochemical technology and geophysics in mineral exploration, mineral resources, mining methods and technology, aspects of beneficiation, pyrometallurgy and hydrometallurgy, and environmental aspects. 4 of the 14 papers have been abstracted separately.

  9. Construction Minerals Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes construction minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  10. Agricultural Minerals Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes agricultural minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  11. Mineral Resources Data System

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Mineral resource occurrence data covering the world, most thoroughly within the U.S. This database contains the records previously provided in the Mineral Resource...

  12. Dietary Supplements and Sports Performance: Minerals

    Directory of Open Access Journals (Sweden)

    Williams Melvin H

    2005-06-01

    Full Text Available Abstract Minerals are essential for a wide variety of metabolic and physiologic processes in the human body. Some of the physiologic roles of minerals important to athletes are their involvement in: muscle contraction, normal hearth rhythm, nerve impulse conduction, oxygen transport, oxidative phosphorylation, enzyme activation, immune functions, antioxidant activity, bone health, and acid-base balance of the blood. The two major classes of minerals are the macrominerals and the trace elements. The scope of this article will focus on the ergogenic theory and the efficacy of such mineral supplementation.

  13. Surface characterization of bacterial cells relevant to the mineral industry

    NARCIS (Netherlands)

    Sharma, PK; Rao, KH

    Bacteria belonging to the Acidithiobacilli group are widely used in the mineral processing industry in bioleaching and biobeneficiation operations. Paenibacillus polymyxa has also found application in biobeneficiation studies. Microbial adhesion to mineral surface is an essential step,for both

  14. Flocculation-coagulation behaviour study of tailings of a fluorspar mineral processing plant; Estudio del comportamiento de las colas de una planta de beneficio de mineral de fluorita frente a procesos floculacion-coagulacion

    Energy Technology Data Exchange (ETDEWEB)

    Dzioba, B. R.; Diaz, A. A.; Menendez-Aguado, J. M.

    2004-07-01

    The objective of this work is to carry out a selection study of the most adequate flocculation-coagulation reagents to reduce the solids content in the overflow from the settling lagoons of a fluorspar processing plant. This overflow has 1/ solids content, clarified from a feed of 25% solids in the settling lagoons, and is pilled into a river. The importance of this work is enhanced by the fact that the plant is located in a low water resources area, and that eventually the water from the river is used for agriculture or even human consumption. It is relevant to find a working methodology which allow to improve the efficiency of the clarifying process and minimize the environmental impact. Regarding the research methodology, a series of trials were made at natural pH and 25 degree centigree to evaluate the action of those reagents which previously probed to be more efficient in this case: as flocculants were tried BOZEFLOC C 65, SEPARAN AP 273 P. SEPARAN MG 200, and as coagulant aluminium sulfate. The possible interaction of flocculation-coagulation processes was also studied, to obtain optimum result. As analysis criterium the total flocculation time was used, and as all essays were made in 100 ml probes, it corresponds with flocculation rate. As result of this study it can be concluded that the most efficient floculant was SEPARAN MG 200, at 4 g/T. with the observation that an excess of aluminium sulfate gets down the efficiency. (Author) 6 refs.

  15. The twenty-first century in space

    CERN Document Server

    Evans, Ben

    2015-01-01

    This final entry in the History of Human Space Exploration mini-series by Ben Evans continues with an in-depth look at the latter part of the 20th century and the start of the new millennium. Picking up where Partnership in Space left off, the story commemorating the evolution of manned space exploration unfolds in further detail. More than fifty years after Yuri Gagarin’s pioneering journey into space, Evans extends his overview of how that momentous voyage continued through the decades which followed. The Twenty-first Century in Space, the sixth book in the series, explores how the fledgling partnership between the United States and Russia in the 1990s gradually bore fruit and laid the groundwork for today’s International Space Station. The narrative follows the convergence of the Shuttle and Mir programs, together with standalone missions, including servicing the Hubble Space Telescope, many of whose technical and human lessons enabled the first efforts to build the ISS in orbit. The book also looks to...

  16. Twenty Years After: Armenian Research Libraries Today

    Directory of Open Access Journals (Sweden)

    D. Aram Donabedian

    2012-05-01

    Full Text Available Since achieving statehood in 1991, Armenia has faced major economic and political obstacles which have significantly affected the nation’s research libraries. This research paper will quantitatively and qualitatively examine the challenges facing Armenian research libraries just over twenty years after the collapse of the Soviet Union. Specifically, the authors analyze their interviews with five library administrators at five major institutions, respectively. These include Yerevan State University Library, the National Library of Armenia, the Fundamental Scientific Library of the National Academy of Sciences of Armenia, the Republican Scientific-Medical Library of Armenia, and the Papazian Library of the American University of Armenia. The instrument for the interviews consists of 73 questions based on the 2004 Association of College and Research Libraries Standards for Libraries in Higher Education and evaluates the following factors:• The library’s mission, goals and objectives• Public or user services• Instruction activities at the library• Resources (print, media, or electronic and collection development• Access to the library’s resources• Outcome assessment, or evaluation of the library• Staffing issues• Facility maintenance and plans for library development• Communication and cooperation both within the library and with the user community• Administration• BudgetIn addition, we will focus on the strengths and weaknesses of these libraries and investigate the growing open access movement in Armenia. Based on our findings, the authors wish to facilitate dialogue and consider possible approaches to help these libraries meet Armenia’s pressing information needs.

  17. Mineral fibres and cancer.

    Science.gov (United States)

    McDonald, J C

    1984-04-01

    A synthesis is presented of the salient findings to date from laboratory and epidemiological research, on the health effects of asbestos and other natural and man-made mineral fibres. Experimental evidence suggests that all mineral fibres are capable of causing fibrosis and malignancy, with chrysotile at least as pathogenic as other fibres. However, penetration, retention and phagocytosis are affected by size and shape and reactivity and durability by physico-chemical properties. Thus it is not surprising that in man the results of exposure vary considerably with fibre type and industrial process. A considerable body of evidence suggests that chrysotile has seldom, if ever, caused peritoneal mesothelioma and that the great majority of pleural mesotheliomas are also attributable to crocidolite or amosite. Without more reliable information on intensity and duration of exposure by fibre type, the epidemiological evidence on this point cannot be wholly conclusive. There are stronger grounds from a limited number of cohort studies for believing that in relation to estimated exposure, the risk of lung cancer has been much higher in textile plants than in fibre production or in the manufacture of friction products, with asbestos-cement plants somewhere in between. The data on man-made fibre production remains equivocal. It is concluded that attempts to regulate asbestos without regard for fibre type, although perhaps adequate for lung cancer and fibrosis, may do little to reduce the risk of mesothelioma. The search for safe fibre substitutes for asbestos will remain difficult until the parameters of pathogenicity are better understood.

  18. Mineral Supply Challenges

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Faced with shortcomings in its mineral supply, it’s imperative for China to balance its desire for reserves with its current economic needs Mineral resources are the corner- stone of materials needed for China’s national economic and social development.The country even counts on its mineral resources to satisfy 90 percent of its energy demands and over 95

  19. An interdisciplinary analysis of multispectral satellite data for selected cover types in the Colorado Mountains, using automatic data processing techniques. [geological lineaments and mineral exploration

    Science.gov (United States)

    Hoffer, R. M. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. One capability which has been recognized by many geologists working with space photography is the ability to see linear features and alinements which were previously not apparent. To the exploration geologist, major lineaments seen on satellite images are of particular interest. A portion of ERTS-1 frame 1407-17193 (3 Sept. 1973) was used for mapping lineaments and producing an iso-lineament intersection map. Skylab photography over the area of prime area was not useable due to snow cover. Once the lineaments were mapped, a grid with 2.5 km spacing was overlayed on the map and the lineament intersections occurring within each grid square were counted and the number plotted in the center of the grid square. These numbers were then contoured producing a contour map of equal lineament intersection. It is believed that the areas of high intersection concentration would be the most favorable area for ore mineralization if favorable host rocks are also present. These highly fractured areas would act as conduits for carrying the ore forming solutions to the site of deposition in a favorable host rock. Two of the six areas of high intersection concentration are over areas of present or past mining camps and small claims are known to exist near the others. These would be prime target areas for future mineral exploration.

  20. Uncertainties in sea level projections on twenty-year timescales

    Science.gov (United States)

    Vinogradova, Nadya; Davis, James; Landerer, Felix; Little, Chris

    2016-04-01

    Regional decadal changes in sea level are governed by various processes, including ocean dynamics, gravitational and solid earth responses, mass loss of continental ice, and other local coastal processes. In order to improve predictions and physical attribution in decadal sea level trends, the uncertainties of each processes must be reflected in the sea level calculations. Here we explore uncertainties in predictions of the decadal and bi-decadal changes in regional sea level induced by the changes in ocean dynamics and associated redistribution of heat and freshwater (often referred to as dynamic sea level). Such predictions are typically based on the solutions from coupled atmospheric and oceanic general circulation models, including a suite of climate models participating in phase 5 of the Coupled Model Intercompasion Project (CMIP5). Designed to simulate long-term ocean variability in response to warming climate due to increasing green-house gas concentration ("forced" response), CMIP5 are deficient in simulating variability at shorter time scales. In contrast, global observations of sea level are available during a relatively short time span (e.g., twenty-year altimetry records), and are dominated by an "unforced" variability that occurs freely (internally) within the climate system. This makes it challenging to examine how well observations compare with model simulations. Therefore, here we focus on patterns and spatial characteristics of projected twenty-year trends in dynamic sea level. Based on the ensemble of CMIP5 models, each comprising a 240-year run, we compute an envelope of twenty-year rates, and analyze the spread and spatial relationship among predicted rates. An ensemble root-mean-square average exhibits large-scale spatial patterns, with the largest uncertainties found over mid and high latitudes that could be attributed to the changes in wind patterns and buoyancy forcing. To understand and parameterize spatial characteristics of the

  1. Protein- mediated enamel mineralization

    Science.gov (United States)

    Moradian-Oldak, Janet

    2012-01-01

    Enamel is a hard nanocomposite bioceramic with significant resilience that protects the mammalian tooth from external physical and chemical damages. The remarkable mechanical properties of enamel are associated with its hierarchical structural organization and its thorough connection with underlying dentin. This dynamic mineralizing system offers scientists a wealth of information that allows the study of basic principals of organic matrix-mediated biomineralization and can potentially be utilized in the fields of material science and engineering for development and design of biomimetic materials. This chapter will provide a brief overview of enamel hierarchical structure and properties as well as the process and stages of amelogenesis. Particular emphasis is given to current knowledge of extracellular matrix protein and proteinases, and the structural chemistry of the matrix components and their putative functions. The chapter will conclude by discussing the potential of enamel for regrowth. PMID:22652761

  2. Mineralized Collagen: Rationale, Current Status, and Clinical Applications

    Directory of Open Access Journals (Sweden)

    Zhi-Ye Qiu

    2015-07-01

    Full Text Available This paper presents a review of the rationale for the in vitro mineralization process, preparation methods, and clinical applications of mineralized collagen. The rationale for natural mineralized collagen and the related mineralization process has been investigated for decades. Based on the understanding of natural mineralized collagen and its formation process, many attempts have been made to prepare biomimetic materials that resemble natural mineralized collagen in both composition and structure. To date, a number of bone substitute materials have been developed based on the principles of mineralized collagen, and some of them have been commercialized and approved by regulatory agencies. The clinical outcomes of mineralized collagen are of significance to advance the evaluation and improvement of related medical device products. Some representative clinical cases have been reported, and there are more clinical applications and long-term follow-ups that currently being performed by many research groups.

  3. Chelated minerals for poultry

    Directory of Open Access Journals (Sweden)

    SL Vieira

    2008-06-01

    Full Text Available Organic minerals have been subject of an increasing number of investigations recently. These compounds can be considered the most significant event regarding commercial forms of minerals targeting animal supplementation in the last decades. Minerals, especially metals, are usually supplemented in poultry feeds using cheap saline sources and have never required a lot of attention in terms of quality. On the other hand, definitions of organic minerals are very broad and frequently lead to confusion when decision-making becomes necessary. Organic minerals include any mineral bound to organic compounds, regardless of the type of existing bond between mineral and organic molecules. Proteins and carbohydrates are the most frequent candidates in organic mineral combinations. Organic fraction size and bond type are not limitations in organic mineral definition; however, essential metals (Cu, Fe, Zn, and Mn can form coordinated bonds, which are stable in intestinal lumen. Metals bound to organic ligands by coordinated bonds can dissociate within animal metabolism whereas real covalent bonds cannot. Chelated minerals are molecules that have a metal bound to an organic ligand through coordinated bonds; but many organic minerals are not chelates or are not even bound through coordinated bonds. Utilization of organic minerals is largely dependent on the ligand; therefore, amino acids and other small molecules with facilitated access to the enterocyte are supposed to be better utilized by animals. Organic minerals with ligands presenting long chains may require digestion prior to absorption. After absorption, organic minerals may present physiological effects, which improve specific metabolic responses, such as the immune response. Many studies have demonstrated the benefits of metal-amino acid chelates on animal metabolism, but the detection positive effects on live performance is less consistent.

  4. Condensate minerals from a burning coal-waste heap in Avion, Northern France

    Energy Technology Data Exchange (ETDEWEB)

    Masalehdani, M.N.N.; Mees, F.; Dubois, M.; Coquinot, Y.; Potdevin, J.L.; Fialin, M.; Blanc-Valleron, M.M. [University of Lille 1, Villeneuve Dascq (France)

    2009-06-15

    A coal-waste heap in Avion, northern France, that has been undergoing subsurface combustion for several decades, is marked by the occurrence of efflorescences at combustion sites where gas and water vapor escape from surficial cracks and vents. Analysis of the efflorescences show that twenty different species of mineral are present, comprising various sulfates, as well as halides and native sulfur. The constituents needed for the formation of these minerals are ultimately derived from the heap of coalmine waste, composed mainly of pyrite-bearing carbonaceous shale, coal and minor amounts of sandstone. They may be partly released by acid weathering of waste-heap materials prior to combustion, but largely by thermal decomposition and oxidation of those materials during combustion processes. Formation of the efflorescences near gas-discharge zones indicates transport of constituent to those zones from the inner part of the waste heap, which can occur in the gas phase for some elements (S, N, H and Cl), but would require droplets of water vapor as carriers for most cations. Interaction between condensate solutions and the local debris at the surface of the waste heap may also contribute to cations input prior to the formation of secondary minerals. Most minerals formed from a liquid phase along the rock-debris surface at low temperatures (T {<=}100 {sup o}C), as confirmed by the occurrence of fluid inclusions. Only salammoniac, native sulfur and mascagnite (where crystallized as a monocrystalline phase) were formed directly from a gas phase. The coal-waste heap shows great variations in mineral assemblages among sampling sites, which must be related to variations in waste composition and in conditions at the level at which the elements are released and where mineral formation takes place.

  5. PMCR-Miner: parallel maximal confident association rules miner algorithm for microarray data set.

    Science.gov (United States)

    Zakaria, Wael; Kotb, Yasser; Ghaleb, Fayed F M

    2015-01-01

    The MCR-Miner algorithm is aimed to mine all maximal high confident association rules form the microarray up/down-expressed genes data set. This paper introduces two new algorithms: IMCR-Miner and PMCR-Miner. The IMCR-Miner algorithm is an extension of the MCR-Miner algorithm with some improvements. These improvements implement a novel way to store the samples of each gene into a list of unsigned integers in order to benefit using the bitwise operations. In addition, the IMCR-Miner algorithm overcomes the drawbacks faced by the MCR-Miner algorithm by setting some restrictions to ignore repeated comparisons. The PMCR-Miner algorithm is a parallel version of the new proposed IMCR-Miner algorithm. The PMCR-Miner algorithm is based on shared-memory systems and task parallelism, where no time is needed in the process of sharing and combining data between processors. The experimental results on real microarray data sets show that the PMCR-Miner algorithm is more efficient and scalable than the counterparts.

  6. Mineral content in teeth with Deciduous Molar Hypomineralisation (DMH)

    NARCIS (Netherlands)

    Elfrink, M.E.C.; ten Cate, J.M.; van Ruijven, L.J.; Veerkamp, J.S.J.

    2013-01-01

    Objectives We report the mineral (hydroxyapatite) density of sound and opaque areas in DMH molars with sound parts of (carious) deciduous teeth serving as controls. Methods Twenty-nine extracted second primary molars obtained from 15 children were studied. Thirteen of these molars were DMH molars

  7. TUCS/phosphate mineralization of actinides

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K.L. [Argonne National Lab., IL (United States)

    1997-10-01

    This program has as its objective the development of a new technology that combines cation exchange and mineralization to reduce the concentration of heavy metals (in particular actinides) in groundwaters. The treatment regimen must be compatible with the groundwater and soil, potentially using groundwater/soil components to aid in the immobilization process. The delivery system (probably a water-soluble chelating agent) should first concentrate the radionuclides then release the precipitating anion, which forms thermodynamically stable mineral phases, either with the target metal ions alone or in combination with matrix cations. This approach should generate thermodynamically stable mineral phases resistant to weathering. The chelating agent should decompose spontaneously with time, release the mineralizing agent, and leave a residue that does not interfere with mineral formation. For the actinides, the ideal compound probably will release phosphate, as actinide phosphate mineral phases are among the least soluble species for these metals. The most promising means of delivering the precipitant would be to use a water-soluble, hydrolytically unstable complexant that functions in the initial stages as a cation exchanger to concentrate the metal ions. As it decomposes, the chelating agent releases phosphate to foster formation of crystalline mineral phases. Because it involves only the application of inexpensive reagents, the method of phosphate mineralization promises to be an economical alternative for in situ immobilization of radionuclides (actinides in particular). The method relies on the inherent (thermodynamic) stability of actinide mineral phases.

  8. Proceedings: Twenty years of energy policy: Looking toward the twenty-first century

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    In 1973, immediately following the Arab Oil Embargo, the Energy Resources Center, University of Illinois at Chicago initiated an innovative annual public service program called the Illinois Energy Conference. The objective was to provide a public forum each year to address an energy or environmental issue critical to the state, region and nation. Twenty years have passed since that inaugural program, and during that period we have covered a broad spectrum of issues including energy conservation nuclear power, Illinois coal, energy policy options, natural gas, alternative fuels, new energy technologies, utility deregulation and the National Energy Strategy.

  9. Industrial mineral powder production in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The recent annual output of major industrial mineral powders in the mainland of China has been more than 100 million t, accompanied by active development of such supporting technology as comminution, classification, separation/purification, and surface modification. In particular, the present paper reviews technologies for preparing ultra-fine particles involving dry and wet processing, modification and composition, calcination of kaolin clay, and processing of spherical/acerous industrial minerals.

  10. Changes in differently processed soya bean (Glycine max.) and lima bean (Phaseolus lunatus) with particular reference to their chemical composition and their mineral and some inherent anti-nutritional constituents.

    Science.gov (United States)

    Aletor, V A; Ojo, O I

    1989-01-01

    The effects of 3 processing techniques: cooking, roasting and autoclaving on the proximate chemical composition, the mineral content and some inherent toxic factors of soya and lima beans were investigated. The processing techniques generally reduced the crude fibre levels and enhanced the extractable fat in the soya and lima beans. The coefficients of variability for crude fibre and ether extract due to the processing techniques of soya and lima beans were 20.9%, 16.0% and 22.3%, 38.1%, respectively. In parallel with decreased ash content in the cooked bean samples, there was a decrease in the K, Mg, Na and P levels relative to the raw bean and also relative to the other processing techniques. Mineral contents of the autoclaved bean samples were generally similar to those of the raw (unprocessed) samples. Under the processing conditions, roasting caused the highest reduction in thioglucoside content (59%) in soya bean while cooking caused the highest reduction in lima bean (78%). Trypsin inhibitor activity (TIA) ranged between 0.59 mg/g sample in the cooked soya bean and 11.6 mg/g sample in the raw bean while the corresponding values for lima bean ranged between 0.59 and 6.3 mg/g sample. Cooking and roasting caused over 90% reduction of TIA, while autoclaving caused 64-69% reduction in both bean samples. Under the assay conditions, haemagglutinating activity was not detected in the cooked and autoclaved soya and lima beans. The need to prevent both functional and nutritional damage to food proteins and other nutrients, resulting from excessive heating, was discussed.

  11. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Science.gov (United States)

    2010-10-01

    ... patents, and mineral leasing within National Forest Wilderness. 19.8 Section 19.8 Public Lands: Interior... § 19.8 Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest... locations, mineral patents, and mineral leasing within National Forest Wilderness are contained in parts...

  12. Textures and mineral compositions of the Xinjie layered intrusion, SW China: Implications for the origin of magnetite and fractionation process of Fe-Ti-rich basaltic magmas

    Directory of Open Access Journals (Sweden)

    Huan Dong

    2013-09-01

    Full Text Available The Xinjie layered intrusion in the Panxi region, SW China, hosts both Fe-Ti oxide and platinum-group element (PGE sulfide mineralization. The intrusion can be divided, from the base upward, into Units I, II and III, in terms of mineral assemblages. Units I and II are mainly composed of wehrlite and clinopyroxenite, whereas Unit III is mainly composed of gabbro. PGE sulfide-rich layers mainly occur in Unit I, whereas thick Fe-Ti oxide-rich layers mainly occur in Unit III. An ilmenite-rich layer occurs at the top of Unit I. Fe-Ti oxides include magnetite and ilmenite. Small amounts of cumulus and intercumulus magnetite occur in Units I and II. Cumulus magnetite grains are commonly euhedral and enclosed within olivine and clinopyroxene. They have high Cr2O3 contents ranging from 6.02 to 22.5 wt.%, indicating that they are likely an early crystallized phase from magmas. Intercumulus magnetite that usually displays ilmenite exsolution occupies the interstices between cumulus olivine crystals and coexists with interstitial clinopyroxene and plagioclase. Intercumulus magnetite has Cr2O3 ranging from 1.65 to 6.18 wt.%, lower than cumulus magnetite. The intercumulus magnetite may have crystallized from the trapped liquid. Large amounts of magnetite in Unit III contains Cr2O3 (<0.28 wt.% much lower than magnetite in Units I and II. The magnetite in Unit III is proposed to be accumulated from a Fe-Ti-rich melt. The Fe-Ti-rich melt is estimated to contain 35.9 wt.% of SiO2, 26.9 wt.% of FeOt, 8.2 wt.% of TiO2, 13.2 wt.% of CaO, 8.3 wt.% of MgO, 5.5 wt.% of Al2O3 and 1.0 wt.% of P2O5. The composition is comparable with the Fe-rich melts in the Skaergaard and Sept Iles intrusions. Paired non-reactive microstructures, granophyre pockets and ilmenite-rich intergrowths, are representative of Si-rich melt and Fe-Ti-rich melt, and are the direct evidence for the existence of an immiscible Fe-Ti-rich melt that formed from an evolved ferro-basaltic magma.

  13. Geochemical constraints on the presence of clay minerals in the Burns formation, Meridiani Planum, Mars

    Science.gov (United States)

    Cino, C. D.; Dehouck, E.; McLennan, S. M.

    2017-01-01

    Burns formation sandstones, deposited by aeolian processes and preserved at Meridiani Planum, Mars, contain abundant sulfate minerals. These sedimentary rocks are thought to be representative of a sulfate-rich geological epoch during late Noachian - early Hesperian time that followed an earlier clay-rich epoch. Twenty Burns formation targets, abraded by the Rock Abrasion Tool (RAT) and for which alpha-particle X-ray spectrometry (APXS) and Mössbauer spectroscopy data are available, were selected for geochemical modeling. A linear unmixing modeling approach was employed. Mineralogical constituents quantitatively constrained by Mössbauer and Mini-TES spectroscopy and interpreted to be chemically precipitated from aqueous fluids during deposition and/or early diagenesis were subtracted from the bulk chemistry. Resulting residual chemical compositions, interpreted to be dominated by detrital siliciclastic components and representing ∼21-35% of the rocks, were then geochemically evaluated to constrain the potential for the presence of clay minerals or their poorly-crystalline or non-crystalline precursors/chemical equivalents. Calculations incorporated a robust estimate of the uncertainties in mineral abundances. On Al2O3 - (CaO+Na2O) - K2O (A-CN-K) and Al2O3 - (CaO+Na2O+K2O) - (FeOtotal+MgO) (A-CNK-FM) molar ternary diagrams, removal of chemical constituents resulted in a shift from igneous-like compositions to compositions consistent with secondary mineral assemblages containing significant aluminous clay mineral components. All of the residual compositions are corundum-normative, further supportive of the presence of highly aluminous phases. On the A-CNK-FM diagram, clay minerals plotting closest to the residual field are natural montmorillonites but could also represent mixtures of various Mg/Fe-rich phyllosilicates, such as nontronite or saponite, and other more Al-rich minerals such as Al-montmorillonite, kaolinite or illite. Depending on the age of clay

  14. A world of minerals in your mobile device

    Science.gov (United States)

    Jenness, Jane E.; Ober, Joyce A.; Wilkins, Aleeza M.; Gambogi, Joseph

    2016-09-15

    Mobile phones and other high-technology communications devices could not exist without mineral commodities. More than one-half of all components in a mobile device—including its electronics, display, battery, speakers, and more—are made from mined and semiprocessed materials (mineral commodities). Some mineral commodities can be recovered as byproducts during the production and processing of other commodities. As an example, bauxite is mined for its aluminum content, but gallium is recovered during the aluminum production process. The images show the ore minerals (sources) of some mineral commodities that are used to make components of a mobile device. On the reverse side, the map and table depict the major source countries producing these mineral commodities along with how these commodities are used in mobile devices. For more information on minerals, visit http://minerals.usgs.gov.

  15. The Surface Groups and Active Site of Fibrous Mineral Materials

    Institute of Scientific and Technical Information of China (English)

    DONG Fa-qin; WAN Pu; FENG Qi-ming; SONG Gong-bao; PENG Tong-jiang; LI Ping; LI Guo-wu

    2004-01-01

    The exposed and transformed groups of fibrous brucite,wollastonite,chrysotile asbestos,sepiolite,palygorskite,clinoptilolite,crocidolite and diatomaceous earth mineral materials are analyzed by IR spectra after acid and alikali etching,strong mechanical and polarity molecular interaction.The results show the active sites concentrate on the ends in stick mineral materials and on the defect or hole edge in pipe mineral materials.The inside active site of mineral materials plays a main role in small molecular substance.The shape of minerals influence their distribution and density of active site.The strong mechanical impulsion and weak chemical force change the active site feature of minerals,the powder process enables minerals exposed more surface group and more combined types.The surface processing with the small polarity molecular or the brand of middle molecular may produce ionation and new coordinate bond,and change the active properties and level of original mineral materials.

  16. Twenty hanging Dolls and a Lynching:

    DEFF Research Database (Denmark)

    Risør, Helene

    2010-01-01

    paradoxical entanglement with the enactments of citizenship and state-citizen relations, the article argues that people's attempts to remain safe constitute a permanent process of making visible and defacing (following Michael Taussig's notion of defacement) dangerousness and criminal subjects vis...

  17. Twenty Years of Diagnosis and the DSM.

    Science.gov (United States)

    Seligman, Linda

    1999-01-01

    The process of diagnosing mental disorders and the use of the Diagnostic and Statistical Manual of Mental Disorders (DSM) have been increasingly important for counselors. This article provides information on the hallmarks of this shift. Reviews and discusses the changes form the third and fourth editions of the DSM. Offers predictions as to future…

  18. Design And Preliminary Testing of a Hammer Mill with End-Suction Lift Capability Suitable for Commercial Processing of Grains and Solid Minerals in Nigeria

    Directory of Open Access Journals (Sweden)

    Ebunilo P. O.

    2010-06-01

    Full Text Available A hammer mill with an end-suction lift capability has been designed, fabricated and tested. The tests were carried out by comparing the product of a conventional hammer mill with that of the new hammer mill with end suction lift capability. The preliminary test results obtained using grains show that the efficiency of a conventional hammer mill and its ability to produce an output of specific size of 400m-600m for both maize and cowpeas is low when compared with the output of the new hammer mill. The new hammer mill, which is a partially closed system while in operation and utilizes suction power, virtually eliminates environmental pollution usually associated with the operation of conventional hammer mills and can be used to mill commonly occurring Nigerian grains like millet, sorghum, maize, cowpeas, guinea-corn and soya beans into flour and also for pulverizing locally occurring solid minerals like clays into powder. This would diversify storage options for the grains, deepen and widen the available food choices for all Nigerians and enhance food security and rural development.

  19. Revisión de los principales modelos para aplicar técnicas de Minería de Procesos (Review of models for applying process mining techniques

    Directory of Open Access Journals (Sweden)

    Arturo Orellana García

    2016-03-01

    Full Text Available Spanish abstract La minería de procesos constituye una alternativa novedosa para mejorar los procesos en una variedad de dominios de aplicación. Tiene como objetivo extraer información a partir de los datos almacenados en los registros de trazas de los sistemas de información, en busca de errores, inconsistencias, vulnerabilidades y variabilidad en los procesos que se ejecutan. Las técnicas de minería de procesos se utilizan en múltiples sectores, como la industria, los servicios web, la inteligencia de negocios y la salud. Sin embargo, para aplicar estas técnicas existen varios modelos a seguir y poca información sobre cual aplicar, al no contar con un análisis comparativo entre estos. La investigación se centró en recopilar información sobre los principales modelos propuestos por autores de referencia mundial en el tema de minería de procesos para aplicar técnicas en el descubrimiento, chequeo de conformidad y mejoramiento de los procesos. Se realiza un análisis de los mismos en función de seleccionar los elementos y características útiles para su aplicación en el entorno hospitalario. La actual investigación contribuye al desarrollo de un modelo para la detección y análisis de variabilidad en procesos hospitalarios utilizando técnicas de minería de procesos. Permite a los investigadores tener de forma centralizada, los criterios para decidir qué modelo utilizar, o qué fases emplear de uno o más modelos. English abstract Process mining is a novel alternative to improve processes in a variety of application domains. It aims to extract information from data stored in records of traces from information systems, looking for errors, inconsistencies, vulnerabilities and variability in processes that are executing. The process mining techniques are used in multiple sectors such as industry, web services, business intelligence and health. However, to apply these techniques there are several models and little information on

  20. Magnetic mineral characterization close to the Yingxiu-Beichuan fault surface rupture zone of the Wenchuan earthquake (Mw 7.9, 2008) and its implication for earthquake slip processes

    Science.gov (United States)

    Liu, Dongliang; Li, Haibing; Lee, Teh-Quei; Sun, Zhiming; Liu, Jiang; Han, Liang; Chevalier, Marie-Luce

    2016-01-01

    The 2008 Mw 7.9 Wenchuan Earthquake produced two major rupture zones: one in the Yingxiu-Beichuan fault zone (YBF) and another in the Anxian-Guanxian fault zone (AGF). A shallow trench was dug in Bajiaomiao village, Dujiangyan, Sichuan Province, which experienced a ∼4.3 m vertical offset during this large earthquake. The hanging wall of the YBF in this trench includes fault gouge and breccia. Optical microscope observations and X-ray diffraction (XRD) measurements show obvious differences between the fault gouge and breccia. Moreover, rock magnetism measurements were collected and include mass magnetic susceptibility (MS), Isothermal Remnant Magnetization (IRM), Saturation Isothermal Remnant Magnetization (SIRM), high-temperature thermo-magnetism (K-T) and magnetic hysteresis loops. Several cm-thick magnetic mineral anomalies are observed close to the Wenchuan Earthquake surface rupture zone of the YBF. Magnetite and Fe-sulfide are the main magnetic carrier materials for the fault rocks close to the surface rupture zone, including 3 cm-thick fault gouge and 3 cm-thick fault breccia, while the other fault breccia, further from the surface rupture zone, contains the paramagnetic minerals. The possible magnetic change is attributed to newly-formed magnetite from paramagnetic minerals at high temperatures (>500 °C) during the large earthquake, implying that the YBF has ever experienced high-temperature thermal pressurization earthquake slip dynamics. Moreover, the YBF has also experienced high-temperature frictional melting earthquake slip dynamics, constrained by the multiple vein pseudotachylite. These high-temperature earthquake slip processes may be responsible for the high dip angle thrust characteristic of the YBF.

  1. Study on Non-Collision Mineralizing Mechanism of Froth Cyclone

    Institute of Scientific and Technical Information of China (English)

    董平; 许占贤; 周晓玲

    2002-01-01

    On the basis of the mineralizing mechanism of froth cyclone, this paper expounds that the froth cyclone flotation process is accomplished in a limited centrifugal field. The main feature of air bubble mineralizing in the froth cyclone is a synthetic mineralizing process, of which the non-collision mineralization of minute air bubble separated out dominates, supplemented with the collision mineralization. Moreover, this paper points out that the hydrophobic separated out and centrifugal force strengthen the selectivity of fine coal particle, accelerate the flotation speed and improve the slime recovery.

  2. An overview of hydrodynamic studies of mineralization

    Directory of Open Access Journals (Sweden)

    Guoxiang Chi

    2011-07-01

    Full Text Available Fluid flow is an integral part of hydrothermal mineralization, and its analysis and characterization constitute an important part of a mineralization model. The hydrodynamic study of mineralization deals with analyzing the driving forces, fluid pressure regimes, fluid flow rate and direction, and their relationships with localization of mineralization. This paper reviews the principles and methods of hydrodynamic studies of mineralization, and discusses their significance and limitations for ore deposit studies and mineral exploration. The driving forces of fluid flow may be related to fluid overpressure, topographic relief, tectonic deformation, and fluid density change due to heating or salinity variation, depending on specific geologic environments and mineralization processes. The study methods may be classified into three types, megascopic (field observations, microscopic analyses, and numerical modeling. Megascopic features indicative of significantly overpressured (especially lithostatic or supralithostatic fluid systems include horizontal veins, sand injection dikes, and hydraulic breccias. Microscopic studies, especially microthermometry of fluid inclusions and combined stress analysis and microthermometry of fluid inclusion planes (FIPs can provide important information about fluid temperature, pressure, and fluid-structural relationships, thus constraining fluid flow models. Numerical modeling can be carried out to solve partial differential equations governing fluid flow, heat transfer, rock deformation and chemical reactions, in order to simulate the distribution of fluid pressure, temperature, fluid flow rate and direction, and mineral precipitation or dissolution in 2D or 3D space and through time. The results of hydrodynamic studies of mineralization can enhance our understanding of the formation processes of hydrothermal deposits, and can be used directly or indirectly in mineral exploration.

  3. Optimization of process parameters for extrusion cooking of low amylose rice flour blended with seeded banana and carambola pomace for development of minerals and fiber rich breakfast cereal.

    Science.gov (United States)

    Borah, Anjan; Lata Mahanta, Charu; Kalita, Dipankar

    2016-01-01

    The low-amylose rice flour, seeded banana (Musa balbisiana, ABB) and carambola (Averrhoa carambola L.) pomace blends were extruded to prepare ready to eat breakfast cereal in a single-screw extruder. Response surface methodology using a central composite design was used to evaluate effect of independent variables, namely blend ratio (80:10:10 - 60:30:10 of low-amylose rice flour, seeded banana and carambola pomace), screw speed (200 - 400 rpm), barrel temperature (90 - 130 (°)C) and feed moisture content (9 - 21 g/100 g, wet basis) on product responses. Quadratic polynomial equations were also obtained by multiple regression analysis. The predicted models were adequate based on lack-of-fit test and coefficient of determination obtained. The feed moisture content had critical effect on all response variables. The compromised optimal conditions obtained by numerical integration for development of extrudates were: screw speed of 350 rpm, barrel temperature of 120 (°)C, feed moisture content of 12 g/100 g and 65:25:10 of blend ratio of feed. In the optimized condition low-amylose rice blend is found to have better physicochemical properties (water absorption index of 481.79 g/100 g; water solubility index of 44.13 g/100 g) and dietary fiber content of 21.35 g/100 g respectively. The developed breakfast cereal showed considerable amount of minerals (Mg and K) and overall acceptability was found to be 7.8.

  4. Experiment Study on Mineral Processing of Phosphorus Ore in Turaif Saudi Arabia%沙特图赖夫磷矿选矿试验研究

    Institute of Scientific and Technical Information of China (English)

    余力; 刘全军; 宋建文; 高扬

    2016-01-01

    There is 19.18% P2O5 and 7.31% MgO in the phosphorus ore from Turaif Saudi Arabia, which belong to the silicon calcium carbonate minerals. Beneifciation experiments were conducted on the ore to obtain the high quality of phosphorus concentrate with low grade magnesium. The results indicated that the series collector of CYH can achieve the separation of phosphorus and magnesium. At the grinding ifneness of 85.64% passing 0.074 mm, dolomite reverse lfotation with mixed acid of phosphoric acid and sulfuric acid as depressor, and CYH-001 as the collector, by the closed-circuit lfow test, it obtained the phosphorus concentrate of theP2O5 grade 32.15% and the recovery rate 72.36%, and the MgO grade 0.77%.%沙特图赖夫磷矿P2O5品位19.18%,MgO品位7.31%,属硅钙质碳酸盐矿,为获得含镁较低的高品位磷精矿,对其进行选矿试验研究。结果表明:CYH系列捕收剂能更好地实现磷、镁分离。在磨矿细度为-0.074 mm含量占85.64%的条件下,以磷酸与硫酸组成的混合酸为磷矿物抑制剂,CYH-001为捕收剂反浮选白云石,通过闭路试验可获得磷精矿P2O5品位32.15%,回收率72.36%;MgO品位0.77%。

  5. Mineral Fiber Toxicology

    Science.gov (United States)

    The chemical and physical properties of different forms of mineral fibers impact biopersistence and pathology in the lung. Fiber chemistry, length, aspect ratio, surface area and dose are critical factors determining mineral fiber-associated health effects including cancer and as...

  6. Mineral commodity summaries 2017

    Science.gov (United States)

    Ober, Joyce A.

    2017-01-31

    This report is the earliest Government publication to furnish estimates covering 2016 nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for more than 90 individual minerals and materials.

  7. Marine Mineral Exploration

    DEFF Research Database (Denmark)

    The past 20 years have seen extensive marine exploration work by the major industrialized countries. Studies have, in part, been concentrated on Pacific manganese nodule occurrences and on massive sulfides on mid-oceanic ridges. An international jurisdictional framework of the sea-bed mineral...... in EEZ areas are fairly unknown; many areas need detailed mapping and mineral exploration, and the majority of coastal or island states with large EEZ areas have little experience in exploration for marine hard minerals. This book describes the systematic steps in marine mineral exploration....... Such exploration requires knowledge of mineral deposits and models of their formation, of geophysical and geochemical exploration methods, and of data evaluation and interpretation methods. These topics are described in detail by an international group of authors. A short description is also given of marine...

  8. Twenty-second symposium (international) on combustion

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The following research areas were discussed at the symposium: coal combustion: carbon burnout, pyrolysis, furnaces, laboratory-scale combustion, and fluidized bed combustion; combustion-generated particulates: soot inception, growth, and soot formation in diffusion flames; engine combustion; turbulent combustion: flames in vortices, fractals and cellular automations, nonpremixed flames, premixed flames, premixed flame structure, and lifted flames; reaction kinetics: hydrocarbon oxidation, free radical chemistry, unsaturated species, aromatics, and nitrogen compounds/pollutant formation; combustion generated NO/sub x/ and SO/sub x/; fires: flame spread, radiation, characterization, and unsteady flames; Laminar flames: structure, opposed-flow combustion, shape, propagation/extinction, and inhibition, oscillations, microgravity; ignition; detonations; dusts; propellants; diagnostics; combustion of drops, sprays, and dispersions, and slurries. Individual projects are processed separately for the data bases. (CBS)

  9. Biomimetic Mineralization of Recombinamer-Based Hydrogels toward Controlled Morphologies and High Mineral Density.

    Science.gov (United States)

    Li, Yuping; Chen, Xi; Fok, Alex; Rodriguez-Cabello, Jose Carlos; Aparicio, Conrado

    2015-11-25

    The use of insoluble organic matrices as a structural template for the bottom-up fabrication of organic-inorganic nanocomposites is a powerful way to build a variety of advanced materials with defined and controlled morphologies and superior mechanical properties. Calcium phosphate mineralization in polymeric hydrogels is receiving significant attention in terms of obtaining biomimetic hierarchical structures with unique mechanical properties and understanding the mechanisms of the biomineralization process. However, integration of organic matrices with hydroxyapatite nanocrystals, different in morphology and composition, has not been well-achieved yet at nanoscale. In this study, we synthesized thermoresponsive hydrogels, composed of elastin-like recombinamers (ELRs), to template mineralization of hydroxyapatite nanocrystals using a biomimetic polymer-induced liquid-precursor (PILP) mineralization process. Different from conventional mineralization where minerals were deposited on the surface of organic matrices, they were infiltrated into the frameworks of ELR matrices, preserving their microporous structure. After 14 days of mineralization, an average of 78 μm mineralization depth was achieved. Mineral density up to 1.9 g/cm(3) was found after 28 days of mineralization, which is comparable to natural bone and dentin. In the dry state, the elastic modulus and hardness of the mineralized hydrogels were 20.3 ± 1.7 and 0.93 ± 0.07 GPa, respectively. After hydration, they were reduced to 4.50 ± 0.55 and 0.10 ± 0.03 GPa, respectively. These values were lower but still on the same order of magnitude as those of natural hard tissues. The results indicated that inorganic-organic hybrid biomaterials with controlled morphologies can be achieved using organic templates of ELRs. Notably, the chemical and physical properties of ELRs can be tuned, which might help elucidate the mechanisms by which living organisms regulate the mineralization process.

  10. Vitamin D endocrinology of bone mineralization.

    Science.gov (United States)

    van Driel, Marjolein; van Leeuwen, Johannes P T M

    2017-09-15

    Bone is a dynamic tissue that is strongly influenced by endocrine factors to restore the balance between bone resorption and bone formation. Bone formation involves the mineralization of the extracellular matrix formed by osteoblasts. In this process the role of vitamin D (1α,25(OH)2D3) is both direct and indirect. The direct effects are enabled via the Vitamin D Receptor (VDR); the outcome is dependent on the presence of other factors as well as origin of the osteoblasts, treatment procedures and species differences. Vitamin D stimulates mineralization of human osteoblasts but is often found inhibitory for mineralization of murine osteoblasts. In this review we will overview the current knowledge of the role of the vitamin D endocrine system in controlling the mineralization process in bone. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Mineral facilities of Europe

    Science.gov (United States)

    Almanzar, Francisco; Baker, Michael S.; Elias, Nurudeen; Guzman, Eric

    2010-01-01

    This map displays over 1,700 records of mineral facilities within the countries of Europe and western Eurasia. Each record represents one commodity and one facility type at a single geographic location. Facility types include mines, oil and gas fields, and plants, such as refineries, smelters, and mills. Common commodities of interest include aluminum, cement, coal, copper, gold, iron and steel, lead, nickel, petroleum, salt, silver, and zinc. Records include attributes, such as commodity, country, location, company name, facility type and capacity (if applicable), and latitude and longitude geographical coordinates (in both degrees-minutes-seconds and decimal degrees). The data shown on this map and in table 1 were compiled from multiple sources, including (1) the most recently available data from the U.S. Geological Survey (USGS) Minerals Yearbook (Europe and Central Eurasia volume), (2) mineral statistics and information from the USGS Minerals Information Web site (http://minerals.usgs.gov/minerals/pubs/country/europe.html), and (3) data collected by the USGS minerals information country specialists from sources, such as statistical publications of individual countries, annual reports and press releases of operating companies, and trade journals. Data reflect the most recently published table of industry structure for each country at the time of this publication. Additional information is available from the country specialists listed in table 2.

  12. The Five Cs of Digital Curation: Supporting Twenty-First-Century Teaching and Learning

    Science.gov (United States)

    Deschaine, Mark E.; Sharma, Sue Ann

    2015-01-01

    Digital curation is a process that allows university professors to adapt and adopt resources from multidisciplinary fields to meet the educational needs of twenty-first-century learners. Looking through the lens of new media literacy studies (Vasquez, Harste, & Albers, 2010) and new literacies studies (Gee, 2010), we propose that university…

  13. Control of Vertebrate Skeletal Mineralization by Polyphosphates

    Science.gov (United States)

    Omelon, Sidney; Georgiou, John; Henneman, Zachary J.; Wise, Lisa M.; Sukhu, Balram; Hunt, Tanya; Wynnyckyj, Chrystia; Holmyard, Douglas; Bielecki, Ryszard; Grynpas, Marc D.

    2009-01-01

    calcium lowers the relative apatite saturation, preventing formation of apatite crystals. Identified in situ within resorbing bone and mineralizing cartilage by the fluorescent reporter DAPI (4′,6-diamidino-2-phenylindole), polyphosphate formation prevents apatite crystal precipitation while accumulating high local concentrations of total calcium and phosphate. When mineralization is required, tissue non-specific alkaline phosphatase, an enzyme associated with skeletal and cartilage mineralization, cleaves orthophosphates from polyphosphates. The hydrolytic degradation of polyphosphates in the calcium-polyphosphate complex increases orthophosphate and calcium concentrations and thereby favors apatite mineral formation. The correlation of alkaline phosphatase with this process may be explained by the destruction of polyphosphates in calcifying cartilage and areas of bone formation. Conclusions/Significance We hypothesize that polyphosphate formation and hydrolytic degradation constitute a simple mechanism for phosphate accumulation and enzymatic control of biological apatite saturation. This enzymatic control of calcified tissue mineralization may have permitted the development of a phosphate-based, mineralized endoskeleton that can be continually remodeled. PMID:19492083

  14. Research on Mineral Processing-metallurgy Combination Technology for an Oxidized Gold Ore in Gansu%甘肃某氧化型金矿石选冶技术研究

    Institute of Scientific and Technical Information of China (English)

    毛益林; 陈晓青; 杨进忠; 王秀芬

    2015-01-01

    甘肃某氧化型金矿石金含量为2.25 g/t,伴生银可综合回收。金主要以独立金矿物形式存在,大部分被载金脉石矿物石英所包裹,少部分以微细粒的形式嵌布在黄铁矿、磁黄铁矿、闪锌矿、黄铜矿和方铅矿等矿物的裂隙中。为高效开发利用该矿石资源,对其进行了选冶联合试验研究。结果表明:在磨矿细度为-0.074 mm占73.00%条件下,经1粗1精2扫浮选、浮选尾矿重选的闭路流程可获得金品位74.2 g/t、回收率91.28%的混合金精矿。混合金精矿经石灰预处理后,经氰化钠浸出,获得了金浸出率为96.52%、金总回收率为88.10%的指标。试验结果对同类型金矿石的选矿回收具有借鉴意义。%The oxidized gold ore in Gansu contains 2. 25 g/t gold and associated silver can be comprehensively recov-ered. Gold mainly exists in form of independent mineral,most gold ore were wrapped in gangue minerals,like quartz,few others was inlayed in the cracks of pyrite,magnetic pyrite,sphalerite,chalcopyrite and galena with the form of fine particles. In order to high efficiently utilize the resource,mineral processing-metallurgy combination experimental research was carried out based on process mineralogy. The results indicate that the mixed concentration with gold grade and recovery of 74. 2 g/t and 91. 28%can be obtained at the grinding fineness of 73. 00% passing 0. 074 mm,via one roughing-one cleaning-two scavenging floatation operation,and gravity separation for floatation tailings. Gold leaching rate of 96. 52% and total recovery of 88. 10% was ob-tained by lime pretreatment with mixed concentrate and then leaching by sodium cyanide. The experimental results can provide technology basis for beneficiation of the ore in same type.

  15. Mineral transformations during the dissolution of uranium ore minerals by dissimilatory metal-reducing bacteria

    Science.gov (United States)

    Glasauer, S.; Weidler, P.; Fakra, S.; Tyliszczak, T.; Shuh, D.

    2011-12-01

    Carnotite minerals [X2(UO2)2(VO4)2]; X = K, Ca, Ba, Mn, Na, Cu or Pb] form the major ore of uranium in the Colorado Plateau. These deposits are highly oxidized and contain U(VI) and V(IV). The biotransformation of U(VI) bound in carnotite by bacteria during dissimilatory metal reduction presents a complex puzzle in mineral chemistry. Both U(VI) and V(V) can be respired by metal reducing bacteria, and the mineral structure can change depending on the associated counterion. We incubated anaerobic cultures of S. putrefaciens CN32 with natural carnotite minerals from southeastern Utah in a nutrient-limited defined medium. Strain CN32 is a gram negative bacterium and a terrestrial isolate from New Mexico. The mineral and metal transformations were compared to a system that contained similar concentrations of soluble U(VI) and V(V). Electron (SEM, TEM) microscopies and x-ray spectromicroscopy (STXM) were used in conjunction with XRD to track mineral changes, and bacterial survival was monitored throughout the incubations. Slow rates of metal reduction over 10 months for the treatment with carnotite minerals revealed distinct biotic and abiotic processes, providing insight on mineral transformation and bacteria-metal interactions. The bacteria existed as small flocs or individual cells attached to the mineral phase, but did not adsorb soluble U or V, and accumulated very little of the biominerals. Reduction of mineral V(V) necessarily led to a dismantling of the carnotite structure. Bioreduction of V(V) by CN32 contributed small but profound changes to the mineral system, resulting in new minerals. Abiotic cation exchange within the carnotite group minerals induced the rearrangement of the mineral structures, leading to further mineral transformation. In contrast, bacteria survival was poor for treatments with soluble U(VI) and V(V), although both metals were reduced completely and formed solid UO2 and VO2; we also detected V(III). For these treatments, the bacteria

  16. Efficient mineralization of antibiotic ciprofloxacin in acid aqueous medium by a novel photoelectro-Fenton process using a microwave discharge electrodeless lamp irradiation.

    Science.gov (United States)

    Wang, Aimin; Zhang, Yanyu; Zhong, Huihui; Chen, Yu; Tian, Xiujun; Li, Desheng; Li, Jiuyi

    2017-08-26

    In this study, a novel photoelectro-Fenton (PEF) process using microwave discharge electrodeless lamp (MDEL) as a UV irradiation source was developed for the removal of antibiotic ciprofloxacin (CIP) in water. Comparative degradation of 200mgL(-1) CIP was studied by direct MDEL photolysis, anodic oxidation (AO), AO in presence of electrogenerated H2O2 (AO-H2O2), AO-H2O2 under MDEL irradiation (MDEL-AO-H2O2), electro-Fenton (EF) and MDEL-PEF processes. Higher oxidation power was found in the sequence: MDEL photolysis removal in MDEL-PEF process were examined, and the optimal conditions were ascertained. The releases of three inorganic ions (F(-), NH4(+) and NO3(-)) and two carboxylic acids (oxalic and formic acids) were qualified. Seven aromatic intermediates mainly generated from hydroxylation, dealkylation and defluorination of CIP were detected by UPLC-QTOF-MS/MS technology. Therefore, plausible degradation sequences for CIP degradation in MDEL-PEF process including all detected products were proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Mineral resources of Antarctica

    Science.gov (United States)

    Compiled and edited by Wright, Nancy A.; Williams, Paul L.

    1974-01-01

    Although the existence of mineral deposits in Antarctica is highly probable, the chances of finding them are quite small. Minerals have been found there in great variety but only as occurrences. Manganese nodules, water (as ice), geothermal energy, coal, petroleum, and natural gas are potential resources that could perhaps be exploited in the future. On the basis of known mineral occurrences in Antarctica and relationships between geologic provinces of Antarctica and those of neighboring Gondwana continents, the best discovery probability for a base-metal deposit in any part of Antarctica is in the Andean orogen; it is estimated to be 0.075 (75 chances in 1,000).

  18. Bioleaching of serpentine group mineral by fungus Talaromyces flavus: application for mineral carbonation

    Science.gov (United States)

    Li, Z.; Lianwen, L.; Zhao, L.; Teng, H.

    2011-12-01

    Many studies of serpentine group mineral dissolution for mineral carbonation have been published in recent years. However, most of them focus mainly on either physical and chemical processes or on bacterial function, rather than fungal involvement in the bioleaching of serpentine group mineral. Due to the excessive costs of the magnesium dissolution process, finding a lower energy consumption method will be meaningful. A fungal strain Talaromyces flavus was isolated from serpentinic rock of Donghai (China). No study of its bioleaching ability is currently available. It is thus of great significance to explore the impact of T. flavus on the dissolution of serpentine group mineral. Serpentine rock-inhabiting fungi belonging to Acremonium, Alternaria, Aspergillus, Botryotinia, Cladosporium, Clavicipitaceae, Cosmospora, Fusarium, Monascus, Paecilomyces, Penicillium, Talaromyces, Trichoderma were isolated. These strains were chosen on the basis of resistance to magnesium and nickel characterized in terms of minimum inhibiting concentration (MIC). Specifically, the strain Talaromyces flavus has a high tolerance to both magnesium (1 mol/L) and nickel (10 mM/L), and we examine its bioleaching ability on serpentine group mineral. Contact and separation experiments (cut-off 8 000-14 000 Da), as well as three control experiments, were set up for 30 days. At least three repeated tests were performed for each individual experiment. The results of our experiments demonstrate that the bioleaching ability of T. flavus towards serpentine group mineral is evident. 39.39 wt% of magnesium was extracted from lizardite during the bioleaching period in the contact experiment, which showed a dissolution rate at about a constant 0.126 mM/d before reaching equilibrium in 13 days. The amount of solubilized Mg from chrysotile and antigorite were respectively 37.79 wt% and 29.78 wt% in the contact experiment. These results make clear the influence of mineral structure on mineral bioleaching

  19. Twenty Years of Systems Engineering on the Cassini-Huygens Mission

    Science.gov (United States)

    Manor-Chapman, Emily

    2013-01-01

    Over the past twenty years, the Cassini-Huygens Mission has successfully utilized systems engineering to develop and execute a challenging prime mission and two mission extensions. Systems engineering was not only essential in designing the mission, but as knowledge of the system was gained during cruise and science operations, it was critical in evolving operational strategies and processes. This paper discusses systems engineering successes, challenges, and lessons learned on the Cassini-Huygens Mission gathered from a thorough study of mission plans and developed scenarios, and interviews with key project leaders across its twenty-year history.

  20. Border Crossing in Contemporary Brazilian Culture: Global Perspectives from the Twenty-First Century Literary Scene

    Directory of Open Access Journals (Sweden)

    Cimara Valim de Melo

    2016-06-01

    Full Text Available Abstract: This paper investigates the process of internationalisation of Brazilian literature in the twenty-first century from the perspective of the publishing market. For this, we analyse how Brazil has responded to globalisation and what effects of cultural globalisation can be seen in the Brazilian literary scene, focusing on the novel. Observing the movement of the novelists throughout the globe, the reception of Brazilian literature in the United Kingdom and the relations between art and the literary market in Brazil, we intend to provoke some reflections on Brazilian cultural history in the light of the twenty-first century.

  1. Border Crossing in Contemporary Brazilian Culture: Global Perspectives from the Twenty-First Century Literary Scene

    Directory of Open Access Journals (Sweden)

    Cimara Valim de Melo

    2016-06-01

    Full Text Available Abstract: This paper investigates the process of internationalisation of Brazilian literature in the twenty-first century from the perspective of the publishing market. For this, we analyse how Brazil has responded to globalisation and what effects of cultural globalisation can be seen in the Brazilian literary scene, focusing on the novel. Observing the movement of the novelists throughout the globe, the reception of Brazilian literature in the United Kingdom and the relations between art and the literary market in Brazil, we intend to provoke some reflections on Brazilian cultural history in the light of the twenty-first century.

  2. Generation process of FeS and its inhibition mechanism on iron mineral reduction in selective direct reduction of laterite nickel ore

    Institute of Scientific and Technical Information of China (English)

    Zhi-guo Liu; Ti-chang Sun; Xiao-ping Wang; En-xia Gao

    2015-01-01

    Numerous studies have demonstrated that Na2SO4 can significantly inhibit the reduction of iron oxide in the selective reduction process of laterite nickel ore. FeS generated in the process plays an important role in selective reduction, but the generation process of FeS and its inhibition mechanism on iron reduction are not clear. To figure this out, X-ray diffraction and scanning electron microscopy analyses were conducted to study the roasted ore. The results show that when Na2SO4 is added in the roasting, the FeO content in the roasted ore in-creases accompanied by the emergence of FeS phase. Further analysis indicates that Na2S formed by the reaction of Na2SO4 with CO reacts with SiO2 at the FeO surface to generate FeS and Na2Si2O5. As a result, a thin film forms on the surface of FeO, hindering the contact be-tween reducing gas and FeO. Therefore, the reduction of iron is depressed, and the FeO content in the roasted ore increases.

  3. Yangzhou’s Famous Twenty-fourth Bridge

    Institute of Scientific and Technical Information of China (English)

    1992-01-01

    “LOOMING green moun-tains and runningstreams;grass does notwither and fall,though the autumnhas come to an end in the south.The bright moon arises overTwenty-fourth Bridge.Where doyou teach pure-jade Yangzhouwomen to play music on bambooflutes?”This poem by Du Mu(803-c.852),a famous poet of thelate Tang Dynasty,is well remem-bered today It made Yangzhou’sTwenty-fourth Bridge Known to la-ter generations.Of many ancientpoems about Twenty-fourth Bridge

  4. [Synthetic mineral fibers].

    Science.gov (United States)

    Boillat, M A

    1999-03-27

    The group of man-made mineral fibres includes slagwool, glasswool, rockwool, glass filaments and microfibres, as well as refractory ceramic fibres. The toxicity of mineral fibres is determined by several factors such as the diameter (ceramic fibres. A slightly elevated standard mortality ratio for lung cancer has been documented in large cohorts of workers (USA, Europe and Canada) exposed to man-made mineral fibres, especially in the early technological phase. It is not possible to determine from these data whether the risk of lung cancer is due to the man-made mineral fibres themselves, in particular due to the lack of data on smoking habits. No increased risk of mesothelioma has been demonstrated in these cohorts. Epidemiological data are insufficient at this time concerning neoplastic diseases in refractory ceramic fibres.

  5. sequenceMiner algorithm

    Data.gov (United States)

    National Aeronautics and Space Administration — Detecting and describing anomalies in large repositories of discrete symbol sequences. sequenceMiner has been open-sourced! Download the file below to try it out....

  6. Vitamins and Minerals

    Science.gov (United States)

    ... minerals your body needs. But if you're skipping meals, dieting, or if you're concerned that ... Kids For Parents MORE ON THIS TOPIC Healthy Breakfast Planner Nutrition & Fitness Center Vitamin D Figuring Out ...

  7. Authigenic minerals: Biologically influenced and induced organomineralization

    Science.gov (United States)

    Dupraz, Christophe

    2016-04-01

    Organominerals are minerals precipitated by interactions with organic matter without enzymatic control. Organomineralization of authigenic carbonate minerals depends on two key components: (1) the "carbonate alkalinity engine" impacting the calcium carbonate saturation index and (2) the organic matrix comprised of extracellular organic matter (EOM), which provides a template for carbonate nucleation. The alkalinity engine can be "intrinsic" when microbial metabolisms increase supersaturation or lower the kinetic barrier of precipitation, or "extrinsic" when the physicochemical environment creates the conditions for mineral formation. The organic matrix produced by various communities within the microbial mats is known to influence nucleation, morphology and mineralogy of minerals through binding of cations. By playing with these two key components, three types of authigenic minerals can be formed: (1) a purely physicochemical precipitation on an abiotic substrate, (2) a precipitation "influenced" by the presence of an organic matrix but resulting from a physicochemical forcing (environmentally driven), or (3) a "microbially-induced" precipitation, in which both supersaturation and organic matrix are resulting from microbial activity. In this keynote, we will review important processes involved in the precipitation of authigenic carbonate minerals in modern microbial mats and open the discussion on the potential use of authigenic carbonate minerals as biosignatures in the fossil record.

  8. Mechanism of mineral formation in bone.

    Science.gov (United States)

    Anderson, H C

    1989-03-01

    The mechanism of mineral formation in bone is seen best where active new bone formation is occurring, e.g., in newly forming subperiosteal bone of the embryo, in the growing bone of young animals, and in healing rickets where the calcification process in osteoid is reactivated. A large body of ultrastructural evidence, using conventional and anhydrous methods for tissue preparation, has shown convincingly that extracellular matrix vesicles are present at or near the mineralization front in all of the above, and that these vesicles are the initial site of apatite mineral deposition. Thus bone resembles growth plate cartilage, predentin, and turkey tendon in having calcification initiated by matrix vesicles. Once the calcification cascade is begun, matrix vesicles are no longer needed to support mineralization and are consumed by the advancing mineralization front in which performed crystals serve as nuclei for the formation of new crystals. The rate of crystal proliferation is promoted by the availability of Ca2+, PO4(3-), and the presence of collagen, and retarded by naturally occurring inhibitors of mineralization such as proteoglycans and several noncollagenous calcium-binding proteins of bone including bone-Gla protein (osteocalcin), phosphoproteins, osteonectin, and alpha-2HS-glycoproteins. New electron microscopic immunocytochemical findings in our laboratory suggest that the origin of alkaline phosphatase-positive bone matrix vesicles is polarized to the mineral-facing side of osteoblasts and may be concentrated near the intercellular junctions of human embryonic osteoblasts.

  9. Mathematical Model for the Mineralization of Bone

    Science.gov (United States)

    Martin, Bruce

    1994-01-01

    A mathematical model is presented for the transport and precipitation of mineral in refilling osteons. One goal of this model was to explain calcification 'halos,' in which the bone near the haversian canal is more highly mineralized than the more peripheral lamellae, which have been mineralizing longer. It was assumed that the precipitation rate of mineral is proportional to the difference between the local concentration of calcium ions and an equilibrium concentration and that the transport of ions is by either diffusion or some other concentration gradient-dependent process. Transport of ions was assumed to be slowed by the accumulation of mineral in the matrix along the transport path. ne model also mimics bone apposition, slowing of apposition during refilling, and mineralization lag time. It was found that simple diffusion cannot account for the transport of calcium ions into mineralizing bone, because the diffusion coefficient is two orders of magnitude too low. If a more rapid concentration gradient-driven means of transport exists, the model demonstrates that osteonal geometry and variable rate of refilling work together to produce calcification halos, as well as the primary and secondary calcification effect reported in the literature.

  10. Metals, minerals and microbes: geomicrobiology and bioremediation.

    Science.gov (United States)

    Gadd, Geoffrey Michael

    2010-03-01

    Microbes play key geoactive roles in the biosphere, particularly in the areas of element biotransformations and biogeochemical cycling, metal and mineral transformations, decomposition, bioweathering, and soil and sediment formation. All kinds of microbes, including prokaryotes and eukaryotes and their symbiotic associations with each other and 'higher organisms', can contribute actively to geological phenomena, and central to many such geomicrobial processes are transformations of metals and minerals. Microbes have a variety of properties that can effect changes in metal speciation, toxicity and mobility, as well as mineral formation or mineral dissolution or deterioration. Such mechanisms are important components of natural biogeochemical cycles for metals as well as associated elements in biomass, soil, rocks and minerals, e.g. sulfur and phosphorus, and metalloids, actinides and metal radionuclides. Apart from being important in natural biosphere processes, metal and mineral transformations can have beneficial or detrimental consequences in a human context. Bioremediation is the application of biological systems to the clean-up of organic and inorganic pollution, with bacteria and fungi being the most important organisms for reclamation, immobilization or detoxification of metallic and radionuclide pollutants. Some biominerals or metallic elements deposited by microbes have catalytic and other properties in nanoparticle, crystalline or colloidal forms, and these are relevant to the development of novel biomaterials for technological and antimicrobial purposes. On the negative side, metal and mineral transformations by microbes may result in spoilage and destruction of natural and synthetic materials, rock and mineral-based building materials (e.g. concrete), acid mine drainage and associated metal pollution, biocorrosion of metals, alloys and related substances, and adverse effects on radionuclide speciation, mobility and containment, all with immense social

  11. Study on Developing Safety Infrastructure for Mineral Processing Waste (NORM Waste) and Contamination Monitoring at the TINT Rare Earth Research & Development Center, Khlong 5, Pathumthani, Thailand

    Science.gov (United States)

    Yaanant, N.; Kasemtanasak, V.; Pattanasub, A.; O-manee, A.; Khaweerat, S.; Pruantonsai, P.; Akharawutchayanon, T.; Nuanjan, P.; Punbut, S.; Srimork, P.; Prasertchiewchan, N.

    2017-06-01

    The objective of this study is to prepare all technical and administrative actions leading to the release of the disused radiological facilities from regulatory control and safe management of radioactive waste. In the first phase, the study covers: the preliminary site characterization, waste characterization, the preparation for authorization of the foreseen strategy and activities. The first phase study shows that several areas of the TINT’s Rare Earth Research & Development Center are contaminated, such as the U/Th extraction, monazite processing and NORM residues storage.

  12. Twenty-Seventh Symposium (International) on Combustion. Volume 1

    Science.gov (United States)

    1998-01-01

    pollutant emissions on human driving the development of highly efficient low- health range from respiratory diseases (e.g., child- emission combustion...Systems (N. 101. Stein, S. E., Walker, J. A., Suryan, M. M., and Fahr , Peters and B. Rogg, eds.), Lecture Notes in Physics, A., in Twenty-Third Symposium...M. M., and Fahr , A., and Kawano, H., Int. j. Chem. Kinet. 21:643-666 in Twenty-Third Symposium (International) on Com- (1989). bustion, The

  13. Minerals Yearbook, volume II, Area Reports—Domestic

    Science.gov (United States)

    ,

    2017-01-01

    The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

  14. Minerals Yearbook, volume III, Area Reports—International

    Science.gov (United States)

    ,

    2017-01-01

    The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

  15. 云南某氧化银矿选矿试验研究%Experimental Study on Mineral Processing Technology for Silver Ore in Yunnan

    Institute of Scientific and Technical Information of China (English)

    缑明亮; 武俊杰; 杨柳; 薛刚; 白新悦

    2014-01-01

    采用浮选+全泥氰化工艺对云南省某银矿石进行提银选矿试验研究。矿石中银多金属复硫盐经浮选富集得到银精粉;浮选尾矿再全泥氰化提银。浮选作业所得银精粉品位5761.54 g/t,回收率21.91%;浮选尾矿全泥氰化浸渣品位19.28 g/t,浸出率78.85%。综合回收率84.12%。银多金属复硫盐是影响浸出率的关键因素,预先将其有效浮选,有利于提高银氰化浸出率。%Some experimental studies have been done on the technical flow and all slime cyanidation for separation of silver ore in Yunnan province. The silver concentrate resulting from silver polymetallic sulfate by flotation contained an amount of silver at 5761.54 g/t with a recovery of 21.91%. The flotation tailings were leached out by all slime cyanidation to produce a concentrate containing 19.28 g/t Ag with a recovery of 78.85%. The total recovery rate was 84.12%. Silver sulfate was the one of key factors affecting the leach of silver in all slime cyanidation process. The flotation to extract firstly silver sulfate facilitated leaching of silver in the following cyanidation process.

  16. 40 CFR 436.60 - Applicability; description of the asphaltic mineral subcategory.

    Science.gov (United States)

    2010-07-01

    ... asphaltic mineral subcategory. 436.60 Section 436.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY Asphaltic Mineral Subcategory § 436.60 Applicability; description of the asphaltic mineral subcategory....

  17. Mineral mixtures from solid salt residues for lambs

    Directory of Open Access Journals (Sweden)

    Daniel Bomfim Manera

    2014-09-01

    Full Text Available The objective of this study was to evaluate water, mineral, feed and nutrient voluntary intakes, in addition to dry matter and nutrient digestibility and the nitrogen balance of lambs fed three mineral supplements. The first treatment consisted of solid salt residue (SSR from an aquaculture tank; the second contained SSR from desalination waste; and the third treatment was control, which corresponded to the supplementation of a commercial mineral supplement. The study lasted 20 days, the first 15 of which were used for animals to adapt to the pens and diets, and the last five days were used for data collection. Twenty-four castrated male lambs with a body weight of 19.72±2.52 kg were utilized in the experiment. The mineral supplements evaluated did not affect the intake and digestibility of the dry matter and nutrients, the water and mineral-salt intake or nitrogen balance. Mineral supplements produced from the SSR from aquaculture tanks and from the desalination waste did not reduce feed, nutrient and water intakes or nutrient digestibility, which suggests that these raw materials can be used in the elaboration of mineral mixtures for lambs.

  18. The mineral economy of Brazil--Economia mineral do Brasil

    Science.gov (United States)

    Gurmendi, Alfredo C.; Barboza, Frederico Lopes; Thorman, Charles H.

    1999-01-01

    This study depicts the Brazilian government structure, mineral legislation and investment policy, taxation, foreign investment policies, environmental laws and regulations, and conditions in which the mineral industry operates. The report underlines Brazil's large and diversified mineral endowment. A total of 37 mineral commodities, or groups of closely related commodities, is discussed. An overview of the geologic setting of the major mineral deposits is presented. This report is presented in English and Portuguese in pdf format.

  19. Mineral mining machines

    Energy Technology Data Exchange (ETDEWEB)

    Mc Gaw, B.H.

    1984-01-01

    A machine for mining minerals is patented. It is a cutter loader with a drum actuating element of the worm type equipped with a multitude of cutting teeth reinforced with tungsten carbide. A feature of the patented machine is that all of the cutting teeth and holders on the drum have the identical design. This is achieved through selecting a slant angle for the cutting teeth which is the mean between the slant angle of the conventional radial teeth and the slant angle of the advance teeth. This, in turn, is provided thanks to the corresponding slant of the holders relative to the drum and (or) the slant of the cutting part of the teeth relative to their stems. Thus, the advance teeth projecting beyond the surface of the drum on the face side and providing upper and lateral clearances have the same angle of attack as the radial teeth, that is, from 20 to 35 degrees. A series of modifications of the cutting teeth is patented. One of the designs allows the cutting tooth to occupy a varying position relative to the drum, from the conventional vertical to an inverted, axially projecting position. In the last case the tooth in the extraction process provides the upper and lateral clearances for the drum on the face side. Among the different modifications of the cutting teeth, a design is proposed which provides for the presence of a stem which is shaped like a truncated cone. This particular stem is designed for use jointly with a wedge which unfastens the teeth and is placed in a holder. The latter is completed in a transverse slot thanks to which the rear end of the stem is compressed, which simplifies replacement of a tooth. Channels are provided in the patented machine for feeding water to the worm spiral, the holders and the cutting teeth themselves in order to deal with dust.

  20. Mineral Commodity Profiles -- Rubidium

    Science.gov (United States)

    Butterman, W.C.; Reese, R.G.

    2003-01-01

    Overview -- Rubidium is a soft, ductile, silvery-white metal that melts at 39.3 ?C. One of the alkali metals, it is positioned in group 1 (or IA) of the periodic table between potassium and cesium. Naturally occurring rubidium is slightly radioactive. Rubidium is an extremely reactive metal--it ignites spontaneously in the presence of air and decomposes water explosively, igniting the liberated hydrogen. Because of its reactivity, the metal and several of its compounds are hazardous materials, and must be stored and transported in isolation from possible reactants. Although rubidium is more abundant in the earth?s crust than copper, lead, or zinc, it forms no minerals of its own, and is, or has been, produced in small quantities as a byproduct of the processing of cesium and lithium ores taken from a few small deposits in Canada, Namibia, and Zambia. In the United States, the metal and its compounds are produced from imported raw materials by at least one company, the Cabot Corporation (Cabot, 2003). Rubidium is used interchangeably or together with cesium in many uses. Its principal application is in specialty glasses used in fiber optic telecommunication systems. Rubidium?s photoemissive properties have led to its use in night-vision devices, photoelectric cells, and photomultiplier tubes. It has several uses in medical science, such as in positron emission tomographic (PET) imaging, the treatment of epilepsy, and the ultracentrifugal separation of nucleic acids and viruses. A dozen or more other uses are known, which include use as a cocatalyst for several organic reactions and in frequency reference oscillators for telecommunications network synchronization. The market for rubidium is extremely small, amounting to 1 to 2 metric tons per year (t/yr) in the United States. World resources are vast compared with demand.

  1. Population dynamics and damage caused by the leaf miner Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae), on seven potato processing varieties grown in temperate environment

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, R.; Carmona, D.; Vincini, A.M.; Monterubbianesi, G. [Universidad Nacional de Mar del Plata (UNMDP), BA (Argentina). Facultad de Ciencias Agrarias. Unidad Integrada EEA Balcarce], e-mail: dcarmona@balcarce.inta.gov.ar; Caldiz, D. [McCain Argentina SA, Balcarce, BA (Argentina). Agronomy Area], e-mail: dcaldiz@mccain.com.ar

    2010-01-15

    The leafminer Liriomyza huidobrensis Blanchard is considered a key pest for potatoes in Argentina. Population dynamics and leaf damage caused by the leafminer on seven selected potato processing varieties were assessed at Balcarce during the 2002 and 2003 growing seasons. Adult population dynamic was monitored using yellow sticky traps, while leaf damage (punctures and mines) was assessed using a damage index scale from low to severe. Liriomyza huidobrensis adults were present throughout the growing season and the population increased along crop development. The same was true for all varieties regarding larval damage, being low on early crop stages and severe late in the season. Varieties were grouped in two different categories according to damage scale index. Shepody, Kennebec, Frital and Innovator showed a higher damage index when compared with Santana, Ranger Russet and Russet Burbank, which exhibited a lower damage. Moreover, it could be assumed that damage was related to the foliage greenness, with light green colored varieties (Shepody, Kennebec, Frital and Innovator) being more attractive and affected by L. huidobrensis. (author)

  2. 紫木节高岭土选矿试验研究%Experimental Research of Mineral Processing on Purple Kibushi Kaolin

    Institute of Scientific and Technical Information of China (English)

    张凌燕; 张格; 王琪; 陆康

    2015-01-01

    内蒙古鄂尔多斯煤系高岭土,因含有较多腐殖质、炭质而呈紫褐色,又称紫木节高岭土。以鄂尔多斯紫木节高岭土为研究对象,对其进行除铁增白试验研究。采用“捣浆-磁选-漂白”工艺流程,可使高岭土煅烧白度由59.49%提高到85.87%,Fe2O3含量从1.38%降到0.74%,达到搪瓷工业一级高岭土(TT-1)的标准。%Inner Mongolia Erdos coal kaolin, because it contains more humus and carbonaceous which make it show the purple-brown, it also called purple kibushi kaolin. The Erdos purple kibushi kaolin was determined as the object of study, and it’s iron removal and bleaching experiments were studied. The use of “chopped-magnetic-bleaching” process, allows Erdos purple kibushi kaolincalcined whiteness increase from 59.49% to 85.87%, the content of Fe2O3 down from 1.38%to 0.74%, and it reaches the ifrst standard of enamel industry.

  3. Sources of organic trace minerals in diets for weaned piglets

    Directory of Open Access Journals (Sweden)

    Gabriela de Mello

    2012-08-01

    Full Text Available One hundred and twenty six piglets from a commercial genetic strain weaned at 21 days of age (6.11±0.42 kg were used to evaluate the effects of supplementation levels of organic sources of trace minerals in the diets of weaned piglets on performance, occurrence of diarrhea, excretion of copper and zinc in the feces, and hematological parameters. A completely randomized block design was adopted, composed of six treatments (diets containing 100% of inorganic trace minerals premix at 3.00 kg/T; diets containing 0, 25, 50, 75 or 100% of organic trace minerals premix, equivalent to 0; 0.75; 1.50; 2.25 or 3.00 kg/T, respectively, seven replicates and three animals per plot. During the experimental period (from 21 to 63 days of age, the increasing levels of organic trace minerals premix in the diets determined a quadratic effect on daily weight gain (DWG, feed conversion (FC, percentage of hematocrit (Ht, hemoglobin (Hb, mean corpuscular hemoglobin (MCH, mean corpuscular volume (MCV, platelets (Pt, and a linear increase of Cu and Zn concentrations in feces. The comparison of means between the treatment with inorganic trace minerals premix and the other treatments showed that piglets fed diets without trace minerals premix had lower values of DWG, Ht, Hb, MCH, MCV, Pt and the worst FC value of piglets fed diets containing 25% of organic trace minerals premix presented lower values of Ht and Hb, in comparison with those fed diets with 100% of inorganic trace minerals premix. Inorganic trace minerals premix can be substituted by organic trace minerals premix at a lower level of inclusion in diets for weaned piglets.

  4. Measuring the Hardness of Minerals

    Science.gov (United States)

    Bushby, Jessica

    2005-01-01

    The author discusses Moh's hardness scale, a comparative scale for minerals, whereby the softest mineral (talc) is placed at 1 and the hardest mineral (diamond) is placed at 10, with all other minerals ordered in between, according to their hardness. Development history of the scale is outlined, as well as a description of how the scale is used…

  5. Mineral Processing Experimental Study on A Gold Mine from Gansu%甘肃某金矿选矿试验研究

    Institute of Scientific and Technical Information of China (English)

    张远宁; 李福兰

    2016-01-01

    甘肃某金矿,金主要是以独立自然金,少量银金矿赋存,与黄铁矿、方铅矿、闪锌矿等硫化矿伴生。采用单一浮选的原则工艺流程就可以获得合格的金精矿,将原矿磨至⁃0.074 mm占75%,经两次粗选、一次扫选产出尾矿,两次精选产出金精矿的工艺流程。添加碳酸钠、丁基黄药和2#油三种药剂。闭路试验获得了金精矿金品位178.85 g/t、金回收率93.95%的较好选矿指标。试验指标良好,为现场生产提供了技术依据。%Gold in a gold mine from Gansu Province was mainly independent native gold, with a small amount of silver gold associated with pyrite, galena and sphalerite. Qualified gold concentrate can be obtained by simple flotation process. The ore was ground to 75% ⁃0.074 mm, followed with two stages of roughing, one scavenging, and two stages of concentrating. So⁃dium carbonate, butyl xanthate and pine oil were used in the flotation. Grade of the gold concentrate form closed circuit test was 178.85 g / t, with a recovery rate of 93.95%. This test index was good, which can provide the technical basis for the field production.

  6. Trace elements and mineral composition of waste produced in the process of combustion of solid fuels in individual household furnaces in the Upper Silesian Industrial Region (Poland

    Directory of Open Access Journals (Sweden)

    Smołka-Danielowska Danuta

    2015-12-01

    Full Text Available This study presents preliminary research results, with regard to the concentration of chosen trace elements (Mn, Cr, Tl, Ni, Cu, Zn, As, Cd, Ba, Pb in waste, which was produced in the process of combustion of solid fuels (hard coal and flotation concentrate of bituminous coal in individual household furnaces in Poland (in the Upper Silesian Industrial Region. 27 samples of ash, 4 samples of hard coal and 2 samples of flotation concentrate of bituminous coal were prepared for the research. Methods such as: ICP-MS, X-ray diffraction by means of the powder method and scanning electron microscopy were used during the research. In the ash samples obtained from the combustion of hard coal, the highest average concentrations were: Mn (1477.7 ppm, Ba (1336.4 ppm and Zn (599.7 ppm. In the samples obtained from the combustion of flotation concentrate of bituminous coal, the highest average concentrations was stated for: Zn (762.4 ppm, Mn (668.5 ppm, Pb (552.1 ppm and Ba (211.7 ppm. Crystalline components were determined by used the X-ray diffraction method and the samples of ash obtained from the combustion of hard coal contained: anhydrite, gypsum, hematite, magnetite, quartz, calcite, mullite, periclase, kaolinite, dolomite, pyrite, sphalerite, galena and feldspars (albite-anorthite. The samples of ash obtained from the combustion of flotation concentrate of bituminous coal contain: pyrite, quartz, potassium feldspar, muscovite and kaolinite. The scanning electron microscope analysis enabled the identification of the chemical composition of single ash grains and determined their morphology (aluminosilicate forms, substance PbS and ZnS, oxides of Ni, Cu and Mn, monazite, xenotime.

  7. Comparative study of cost-benefit integrated system of water spary with industrial ventilation and bag filters in a minerals processing company

    Directory of Open Access Journals (Sweden)

    Morteza Babaei

    2016-06-01

    Full Text Available Introduction: Control of fugitative dust from mining process and application of an appropriate and economical system for dust collecting is essential. The goal of this study was cost-benefit analysis of an integrated systems and compare to bag filter in a crushing plant of a mining company. Methods: A local exhaust ventilation system for capture of emitted particlees, a water spray for dust suppresion at sources and parallel Stairmand model cyclones as dust colletor were designed and installed based on the standards and guidelines. Then, efficiency of wetting and industrial ventilation system for control of ambient dust personal exposure and environmental emission have evaluated as integrated and alone. Finally, cost-benefit analysis of this system was compared to bag filter. Results: The efficiency of this system for control personal exposure repairable particles and emitted dust to ambient air was 87% and 95% for plant 1 and 88% and 95% for plant 2, respectively. The concentration of emitted emitted dust from stack to environment were 121.28 mg/m3 and 112/68 mg/m3 for plant 1 and 2, respectively. The capital, operational and maintence costs of this option was 217 and 0.992 billion rials lower than bag filter. Also, annuall collected dust by cyclones was worth 518 million rial. Conclusion: According to results, integrated system had a significant impact on emitted dust in workplace and environment. The economical analysis domonstrated 73% and 80% savings in capital and operational costs compared to bag filter. Total costs of implented project will be compensated at 220 day with recovered dusts, therefore, in the same condition, it can be suggested as the favourable and economical solution.

  8. Effects of germination and high hydrostatic pressure processing on mineral elements, amino acids and antioxidants in vitro bioaccessibility, as well as starch digestibility in brown rice (Oryza sativa L.).

    Science.gov (United States)

    Xia, Qiang; Wang, Liping; Xu, Congcong; Mei, Jun; Li, Yunfei

    2017-01-01

    The effects of germination and high hydrostatic pressure (HHP) processing on the in vitro bioaccessibility of mineral elements, amino acids (AAs), antioxidants and starch in brown rice (BR) were investigated. Germinated BR (GBR) was obtained by incubating at 37°C for 36h and then subjected to HHP treatments at 0.1, 100, 300 and 500MPa for 10min. The in vitro bioaccessibility of calcium and copper was increased by 12.59-52.17% and 2.87-23.06% after HHP, respectively, but bioaccessible iron was decreased. In addition, HHP significantly improved individual AAs, particularly indispensable AAs and gama-aminobutyric acid, as well as bioaccessible total antioxidant activities and starch resistance to enzymatic hydrolysis. However, germination greatly increased starch digestibility. Atomic force microscopy characterization suggested an obvious structural change in bran fraction at pressures above 300MPa. These results can help to understand the effects of germination and HHP technologies on nutrients bioaccessibility and develop appropriate processing conditions. Copyright © 2016. Published by Elsevier Ltd.

  9. Analysis of Mineralization System and Prediction of New-Type Ore Deposits

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mineralization system is of great importance to the discovery of new-type ore deposits. ① The understanding of the relationship among various ore deposit types within a mineralization system in a region can help us to locate the unknown ore deposit types from the known ore deposit types, evidence that has been proved in the mineral prospecting history of ore belts in the middle and lower reaches of the Yangtze River, China. ② The understanding of the spatial structure of a mineralization system, especially of the vertical zonation, is helpful for the discovery of the concealed ore deposit types. ③ Clarifying the temporal structure of a mineralization system, including the iteration relationship between the mineral deposit types in the mineralization, leads to the location of the missing mineralization chains from the known mineralization chains (mineral deposit type), a method often proved to be effective in the magmatic-hydrothermal mineralization system. ④ Clarifying the factors restraining the diversity of mineral deposit types in mineralization system leads to the discovery of the potential of new-type mineral deposits in relevant region. ⑤ Studying new mineralization setting and new ore-forming processes leads to discovery of new-type mineral deposit. More probabilities of discovery of new-type mineral deposits are present in biogenic mineralization system, deep-sea mineralization system, low-temperature mineralization system, tectonic mineralization system and superimposed mineralization system.

  10. Extraterrestrial magnetic minerals

    Science.gov (United States)

    Pechersky, D. M.; Markov, G. P.; Tsel'movich, V. A.; Sharonova, Z. V.

    2012-07-01

    Thermomagnetic and microprobe analyses are carried out and a set of magnetic characteristics are measured for 25 meteorites and 3 tektites from the collections of the Vernadsky Geological Museum of the Russian Academy of Sciences and Museum of Natural History of the North-East Interdisciplinary Science Research Institute, Far Eastern Branch of the Russian Academy of Sciences. It is found that, notwithstanding their type, all the meteorites contain the same magnetic minerals and only differ by concentrations of these minerals. Kamacite with less than 10% nickel is the main magnetic mineral in the studied samples. Pure iron, taenite, and schreibersite are less frequent; nickel, various iron spinels, Fe-Al alloys, etc., are very rare. These minerals are normally absent in the crusts of the Earth and other planets. The studied meteorites are more likely parts of the cores and lower mantles of the meteoritic parent bodies (the planets). Uniformity in the magnetic properties of the meteorites and the types of their thermomagnetic (MT) curves is violated by secondary alterations of the meteorites in the terrestrial environment. The sediments demonstrate the same monotony as the meteorites: kamacite is likely the only extraterrestrial magnetic mineral, which is abundant in sediments and associated with cosmic dust. The compositional similarity of kamacite in iron meteorites and in cosmic dust is due to their common source; the degree of fragmentation of the material of the parent body is the only difference.

  11. A High-Resolution Multitechniques Approach to Characterize Bio-Organo-Mineral Associations Within Rock Samples: Tracking Biological vs Abiotic Processes? Towards a Better Understanding of the Deep Carbon Cycle.

    Science.gov (United States)

    Pisapia, C.

    2015-12-01

    Among all elements, carbon plays one of the major roles for the sustainability of life on Earth. Past considerations of the carbon cycle have mainly focused on surface processes occurring at the atmosphere, oceans and shallow crustal environments. By contrast, little is known about the Deep Carbon cycle whereas both geochemical and biological processes may induce organic carbon production and/or consumption at depth. Indeed, the nowadays-recognized capability of geochemical processes such as serpentinization to generate abiotic organic compounds as well as the existence of a potentially important intraterrestrial life raises questions about the limit of biotic/abiotic carbon on Earth's deep interior and how it impacts global biogeochemical cycles. It is then mandatory to increase our knowledge on the nature and extent of carbon reservoirs along with their sources, sinks and fluxes in the subsurface. This implies to be able to finely characterize organomineral associations within crustal rocks although it might be hampered by the scarceness and heterogeneous micrometric spatial distribution of organic molecules in natural rocks. We then developed an in situ analytical strategy based on the combination of high-resolution techniques to track organic molecules at the pore level in natural rocks and to determine their biological or abiotic origin. We associated classical high-resolution techniques and synchrotron-based imaging techniques in order to characterize their nature and localization (SEM/TEM, coupled CLSM/Raman spectroscopy, Tof-SIMS) along with their 3D-distribution relatively to mineral phases (S-FTIR, S-DeepUV, XANES, Biphoton microscopy). The effectiveness of this approach to shed light on the speciation and nature of carbon in subsurface environments will be illustrated through the study of (i) subsurface ecosystems and abiotic organic carbon within ultramafic rocks of the oceanic lithosphere as putative analogs for the nature and functioning of primitive

  12. THE USE OF FLUORIDE CONTAINING MINERAL WATER IN WORT PRODUCTION

    OpenAIRE

    Gunka Yonkova; Vanja Zhivkova; Andriana Surleva

    2011-01-01

    The present work aims to study the quality of wort produced using fluoride containing mineral water. The results show that the mineral water has a negative impact on the enzymatic destruction of starch, proteins, color intensity and pH of the wort. The changes of pH during mashing process using tap and mineral water was studied. The lower acidity of wort obtained using mineral water didn’t change during the brewing process. The fluoride content of beer is lower than 5 mg.L-1 when wort is prod...

  13. On Mineral Retrosynthesis of a Complex Biogenic Scaffold

    Directory of Open Access Journals (Sweden)

    Ashit Rao

    2017-03-01

    Full Text Available Synergistic relations between organic molecules and mineral precursors regulate biogenic mineralization. Given the remarkable material properties of the egg shell as a biogenic ceramic, it serves as an important model to elucidate biomineral growth. With established roles of complex anionic biopolymers and a heterogeneous organic scaffold in egg shell mineralization, the present study explores the regulation over mineralization attained by applying synthetic polymeric counterparts (polyethylene glycol, poly(acrylic acid, poly(aspartic acid and poly(4-styrenesulfonic acid-co-maleic acid as additives during remineralization of decalcified eggshell membranes. By applying Mg2+ ions as a co-additive species, mineral retrosynthesis is achieved in a manner that modulates the polymorph and structure of mineral products. Notable features of the mineralization process include distinct local wettability of the biogenic organic scaffold by mineral precursors and mineralization-induced membrane actuation. Overall, the form, structure and polymorph of the mineralization products are synergistically affected by the additive and the content of Mg2+ ions. We also revisit the physicochemical nature of the biomineral scaffold and demonstrate the distinct spatial distribution of anionic biomolecules associated with the scaffold-mineral interface, as well as highlight the hydrogel-like properties of mammillae-associated macromolecules.

  14. Thin Ice Films at Mineral Surfaces.

    Science.gov (United States)

    Yeşilbaş, Merve; Boily, Jean-François

    2016-07-21

    Ice films formed at mineral surfaces are of widespread occurrence in nature and are involved in numerous atmospheric and terrestrial processes. In this study, we studied thin ice films at surfaces of 19 synthetic and natural mineral samples of varied structure and composition. These thin films were formed by sublimation of thicker hexagonal ice overlayers mostly produced by freezing wet pastes of mineral particles at -10 and -50 °C. Vibration spectroscopy revealed that thin ice films contained smaller populations of strongly hydrogen-bonded water molecules than in hexagonal ice and liquid water. Thin ice films at the surfaces of the majority of minerals considered in this work [i.e., metal (oxy)(hydr)oxides, phyllosilicates, silicates, volcanic ash, Arizona Test Dust] produced intense O-H stretching bands at ∼3400 cm(-1), attenuated bands at ∼3200 cm(-1), and liquid-water-like bending band at ∼1640 cm(-1) irrespective of structure and composition. Illite, a nonexpandable phyllosilicate, is the only mineral that stabilized a form of ice that was strongly resilient to sublimation in temperatures as low as -50 °C. As mineral-bound thin ice films are the substrates upon which ice grows from water vapor or aqueous solutions, this study provides new constraints from which their natural occurrences can be understood.

  15. 从某铜多金属选厂尾矿中综合回收钨的试验研究%Experimental Research on Multipurpose Utilization of Tungsten from a Certain Copper Polymetallic Mineral Processing Plant Tailings

    Institute of Scientific and Technical Information of China (English)

    赵淑兰; 方晓红; 贾凤梅; 秦丽

    2014-01-01

    The content of tungsten in tailings of a certain copper polymetallic mineral processing plant in Inner Mongolia is WO 3 0 .40%, since the fine particle size , complex components of sul-fide, uneven distribution of tungsten content and dissemination with each other in selected tailings , the original recovery process is not suitable , leading to recovery of tungsten is low in production .In order to improve the recovery of tungsten , the joint process of pre -throwing tailings by centrifugal concentrator , desulphurizing by floatation , gravity separating by shaker and high intensity magnetic separation is used to recover fine grain tungsten , obtained a wolfram products concentrate with 70 . 58%WO3 ,58.53%of recovery.The separation results is better , effectively recovered the tailings resources .%内蒙某铜多金属选厂尾矿中钨含量WO30.40%,由于入选尾矿粒度变细、硫化矿组分复杂、含量分布不均且互相嵌连包含,矿山原有回收工艺已不适合,导致生产中钨的回收率偏低。为了提高钨的回收率,采用离心选矿机预先抛尾-浮选脱硫-重选-强磁选回收细粒钨的联合工艺流程,获得了WO3品位70.58%、回收率58.53%的钨精矿,选别效果较好,有效回收了钨资源。

  16. U.S. Geological Survey mineral databases; MRDS and MAS/MILS

    Science.gov (United States)

    McFaul, E.J.; Mason, G.T.; Ferguson, W.B.; Lipin, B.R.

    2000-01-01

    These two CD-ROM's contain the latest version of the Mineral Resources Data System (MRDS) database and the Minerals Availability System/Minerals Industry Location System (MAS/MILS) database for coverage of North America and the world outside North America. The records in the MRDS database each contain almost 200 data fields describing metallic and nonmetallic mineral resources, deposits, and commodities. The records in the MAS/MILS database each contain almost 100 data fields describing mines and mineral processing plans.

  17. Nanofiltration renovation of mineral water

    Directory of Open Access Journals (Sweden)

    Bodzek Michał

    2017-06-01

    Full Text Available There is often a need to improve the taste of mineral water by reducing the sulphate ion content. It was found that for such an effect, nanofiltration (NF process can be used. In the case, the proposed formula was assumed obtaining a mineral water with reduction of H2S and SO42- content through the following processes: stripping - UF/MF or rapid fi ltration - nanofiltration - mixing with raw water or filtration through calcium bed. The paper shows the results of the tests, with use of mineral waters and nanofiltration. Commercial nanofiltration membranes NF-270 Dow Filmtec and NF-DK GE Infrastructure Water&Process Technologies were applied. NF was carried out for mixed water from both water intakes (1 and 2, recovery of 50%, at transmembrane pressure of 0.8-1.2 MPa in the dead-end fi ltration mode. In addition, the permeate obtained in NF was filtered through a column fi lled with 1.0-3.0 mm limestone rock, in order to improve the composition of mineral water. The tested mineral water is the sulphate-chloride-sodium-calcium-magnesium in nature and contains 991 mg/L of SO42- and 2398 mg/L of TDS, while the permeate after NF showed the chloride - sodium hydrogeochemical type (TDS: 780-1470 mg/L, sulfate 10-202.7 mg/L, calcium 23-39.7 mg/L, magnesium 11-28 mg/L. As a result of water treatment in the NF process, high reduction of SO42- ions was obtained (79-98.7%, while the TDS was reduced in 51-64%. Because the process of NF allows for relatively high reduction of bivalent ions, a significant reduction in calcium ion content (84-88% and magnesium (84-89% has been also obtained. Monovalent ions were reduced to a lesser extent, i.e. sodium in 46% and bicarbonates in 39-64.1%. Despite obtaining the positive effect of the sulphate ions content reduction, the NF process significantly changed the mineralogy composition of water. The permeate filtration (DK-NF membrane on the CaCO3 deposit led to a correction of the hydrogeochemical type of water from

  18. Design and Realization of Mineral Feeding SCADA System

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The grinding process in concentration plants of the metallurgical industry is of great importantce.. A mineral feeding SCADA system in the grinding process was designed with the idea of integrating management and control functions. A detailed design and realization method of control and supervisory control levels in the system was introduced. At the control level, with an algorithm of a separate integrated PID, four mineral feeding machines are run in turn. The supervisory control level can generate process flow graphs, statistical report forms, historical trends and at the same time, it has the functions of alarm, system administration, user login, etc. After the mineral SCADA system has been started, the mineral feeding is very stable, the workstation completely supervises and controls the entire process of mineral feeding, and at the same time historical data is shown and questions can be answered conveniently. The system runs well in the MeiShan Concentration Plant of the Shanghai Bao Shan Steel Group.

  19. Mineralization of fossil wood

    NARCIS (Netherlands)

    Buurman, P.

    1972-01-01

    Several pieces of fossil wood have been analyzed with X-ray diffraction and were grouped on the basis of mineralogical composition. Various mineralizations were studied in thin sections and by means of the scanning electron microscope. Wood-opals appear to show a structure preservation that points t

  20. Clay Mineral: Radiological Characterization

    Science.gov (United States)

    Cotomácio, J. G.; Silva, P. S. C.; Mazzilli, B. P.

    2008-08-01

    Since the early days, clays have been used for therapeutic purposes. Nowadays, most minerals applied as anti-inflammatory, pharmaceutics and cosmetic are the clay minerals that are used as the active ingredient or, as the excipient, in formulations. Although their large use, few information is available in literature on the content of the radionuclide concentrations of uranium and thorium natural series and 40K in these clay minerals. The objective of this work is to determine the concentrations of 238U, 232Th, 226Ra, 228Ra, 210Pb and 40K in commercial samples of clay minerals used for pharmaceutical or cosmetic purposes. Two kinds of clays samples were obtained in pharmacies, named green clay and white clay. Measurement for the determination of 238U and 232Th activity concentration was made by alpha spectrometry and gamma spectrometry was used for 226Ra, 228Ra, 210Pb and 40K determination. Some physical-chemical parameters were also determined as organic carbon and pH. The average activity concentration obtained was 906±340 Bq kg-1 for 40K, 40±9 Bq kg-1 for 226Ra, 75±9 Bq kg-1 for 228Ra, 197±38 Bq kg-1 for 210Pb, 51±26 Bq kg-1 for 238U and 55±24 Bq kg-1 for 232Th, considering both kinds of clay.

  1. Mixtures and mineral reactions

    Energy Technology Data Exchange (ETDEWEB)

    Saxena, S.; Ganguly, J.

    1987-01-01

    Considerable progress has been made in our understanding of the physicochemical evolution of natural rocks through systematic analysis of the compositional properties and phase relations of their mineral assemblages. This book brings together concepts of classical thermodynamics, solution models, and atomic ordering and interactions that constitute a basis of such analysis, with examples of application to subsolidus petrological problems.

  2. 镜铁山周边某微细粒磁铁矿选矿工艺研究%Mineral Processing Technology for Microfine Magnetite from Mines Adjacent to Jingtieshan Deposit

    Institute of Scientific and Technical Information of China (English)

    王永刚; 杨云虎

    2016-01-01

    对酒钢镜铁山周边某微细粒磁铁矿进行了选矿工艺研究。采用Na2 CO3+NaOH调整矿浆pH值为11,以六偏磷酸钠分散矿浆,添加腐植酸钠进行选择性絮凝磁选,可获得铁精矿品位63.31%、回收率79.45%,精矿品位比常规磁选提高了1.77个百分点,回收率提高了3.36个百分点。%Mineral processing technology for microfine magnetite from mines around Jingtieshan in Jiu Steel Group was studied. With Na2 CO3 and NaOH to regulate pulp pH as 11, hexametaphosphate to disperse slurry, sodium humate to selectively flocculate magnetite for magnetic separation, iron concentrate grading 63. 31% Fe at 79. 45% recovery was finally obtained, indicating up by 1. 77 percentage points in the grade and 3. 36 percentage points in the recovery, compared with the conventional magnetic separation.

  3. Experimental Research on the Mineral Processing Technology for Treating an Antimony Ore in Shangnan,Shanxi%陕西商南某锑矿选矿试验研究

    Institute of Scientific and Technical Information of China (English)

    孙阳; 王红梅; 李素玮; 王建斌

    2009-01-01

    根据矿石性质进行了锑硫分离回收有价元素锑的选矿试验研究.结果表明:采用糊精抑制黄铁矿,可达到锑硫分离的目的;采用混合型捕收剂,既提高了锑精矿的品位(51.76%),又保证了锑精矿的回收率(76.08%).%According to the ore properties,an experimental research on mineral processing technology for separating antimony from sulfur and recovering valuable elements was performed. The results showed that by using dextrin as the depressant of pyrite,the purpose of separating antimony from sulfur can be satisfactorily reached. When a combined collector is adopted,this kind of reagent can not only increase the grade of antimony concentrate(51.76%),but also ensure higher recovery of antimony concentrate(76.08%).

  4. The Need for Accurate Geometric and Radiometric Corrections of Drone-Borne Hyperspectral Data for Mineral Exploration: MEPHySTo—A Toolbox for Pre-Processing Drone-Borne Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Sandra Jakob

    2017-01-01

    Full Text Available Drone-borne hyperspectral imaging is a new and promising technique for fast and precise acquisition, as well as delivery of high-resolution hyperspectral data to a large variety of end-users. Drones can overcome the scale gap between field and air-borne remote sensing, thus providing high-resolution and multi-temporal data. They are easy to use, flexible and deliver data within cm-scale resolution. So far, however, drone-borne imagery has prominently and successfully been almost solely used in precision agriculture and photogrammetry. Drone technology currently mainly relies on structure-from-motion photogrammetry, aerial photography and agricultural monitoring. Recently, a few hyperspectral sensors became available for drones, but complex geometric and radiometric effects complicate their use for geology-related studies. Using two examples, we first show that precise corrections are required for any geological mapping. We then present a processing toolbox for frame-based hyperspectral imaging systems adapted for the complex correction of drone-borne hyperspectral imagery. The toolbox performs sensor- and platform-specific geometric distortion corrections. Furthermore, a topographic correction step is implemented to correct for rough terrain surfaces. We recommend the c-factor-algorithm for geological applications. To our knowledge, we demonstrate for the first time the applicability of the corrected dataset for lithological mapping and mineral exploration.

  5. Study on degradation law of remaining xanthate in mineral processing waste water%选矿废水中残余黄药降解规律的试验研究

    Institute of Scientific and Technical Information of China (English)

    翁建浩; 王睿; 黄道玉

    2001-01-01

    为探索选矿废水中残余黄药降解规律,进行了不同pH值、不同起始浓度的黄药水溶液的自然曝晒试验;并进行了温度、光照对黄药水溶液降解影响的研究试验。结果表明:pH4.5、较高温度以及紫外光照射对黄药降解十分有利。%In order to exploring degradation law of remaining xanthate in mineral processing waste water, natural solarization tests of xanthate solution with different pH value and different initiation density were carried out. The tests with different temperature and light also were carried out. It was shown that in the condition of pH4.5, high temperature and ultraviolet lighting were beneficial to the xanthate degradation.

  6. LEACHABILITY OF METALS FROM MINERAL PROCESSING WASTE

    Science.gov (United States)

    This report was submitted by the University of Cincinnati (UC) in fulfillment of Contract No. 68-C7-0057 under the sponsorship of the United States Environmental Protection Agency (EPA). This report covers a period from August 2000 through November 2001; laboratory work was com...

  7. Mineral concentrate from processed manure as fertiliser

    NARCIS (Netherlands)

    Velthof, G.L.

    2015-01-01

    Mestverwerking is een optie om de benutting van nutriënten in mest te verhogen. Mineralenconcentraat, een geconcentreerde oplossing van stikstof (N) en kalium (K), is een van de producten die kan worden geproduceerd via mestverwerking. Het mineralenconcentraat wordt geproduceerd door middel van omge

  8. Aggregate and Mineral Resources - Industrial Mineral Mining Operations

    Data.gov (United States)

    NSGIC Education | GIS Inventory — An Industrial Mineral Mining Operation is a DEP primary facility type related to the Industrial Mineral Mining Program. The sub-facility types are listed below:Deep...

  9. Aggregate and Mineral Resources - Industrial Mineral Mining Operations

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — An Industrial Mineral Mining Operation is a DEP primary facility type related to the Industrial Mineral Mining Program. The sub-facility types are listed below:Deep...

  10. Cyanobacteria as Biocatalysts for Carbonate Mineralization

    Directory of Open Access Journals (Sweden)

    Christer Jansson

    2012-10-01

    Full Text Available Microbial carbonate mineralization is widespread in nature and among microorganisms, and of vast ecological and geological importance. However, our understanding of the mechanisms that trigger and control processes such as calcification, i.e., mineralization of CO2 to calcium carbonate (CaCO3, is limited and literature on cyanobacterial calcification is oftentimes bewildering and occasionally controversial. In cyanobacteria, calcification may be intimately associated with the carbon dioxide-(CO2 concentrating mechanism (CCM, a biochemical system that allows the cells to raise the concentration of CO2 at the site of the carboxylating enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco up to 1000-fold over that in the surrounding medium. A comprehensive understanding of biologically induced carbonate mineralization is important for our ability to assess its role in past, present, and future carbon cycling, interpret paleontological data, and for evaluating the process as a means for biological carbon capture and storage (CCS. In this review we summarize and discuss the metabolic, physiological and structural features of cyanobacteria that may be involved in the reactions leading to mineral formation and precipitation, present a conceptual model of cyanobacterial calcification, and, finally, suggest practical applications for cyanobacterial carbonate mineralization.

  11. Uranium Recovery from Uranium Mineral Bio-Heap Residues with Microbial Column Leaching Process%微生物柱浸法从铀矿石堆浸尾渣中回收铀的研究

    Institute of Scientific and Technical Information of China (English)

    李江; 刘亚洁; 车江华; 饶军

    2012-01-01

    Column bio-leaching tests under different spraying conditions on the uranium mineral bio-heap residues were conducted with bio-heap leaching process. The uranium content of the residues was 0. 014%. The results show that the leaching rate is 50% after a leaching period of four months with ratio of liquid to solid of L 74 and one spray for two-days, while the leaching rate is 28- 6% with ratio of liquid to solid of 0. 94 and one spray for four-days. This leaching process with small and interval spray has the advantages of low cost, efficient uranium recovery from the bio-heap residues and less environmental pollution.%对广东某铀矿微生物堆浸后品位为0.014%的尾渣进行了不同喷淋条件下的微生物柱浸试验.结果表明,浸出周期4个月,在2天喷淋1次条件下,液固比为1.74,渣计浸出率50%;在4天喷淋1次条件下,液固比为0.94,渣计浸出率28.6%.小喷淋量、间歇式喷淋的微生物浸出工艺,成本低,能有效回收堆浸尾渣中的铀资源,同时减少环境污染.

  12. 内蒙古某低品位银多金属硫化矿选矿工艺试验研究%Study on mineral processing technology for a low grade silver polymetallic sulfide ore from Inner Mongolia

    Institute of Scientific and Technical Information of China (English)

    周兵仔; 刘建远

    2015-01-01

    In this paper,the mineral processing studyhas been carried out for solvingtechnological problems of a silver polymetallic sulfide ore from Inner Mongolia.A novel processing technology has beendeveloped to recover copper and lead by bulk-flotation and separation,followed by zinc-flotation using non-toxic reagent.Saleablecopper concentrate,lead concentrate and zinc concentrate products have been obtained respectively.50.39 percent of Cu,70.08 percent of Pb and 79.09 percent of Zn have been recovered.The total recovery of Ag in copper and lead concentrates was 65.47 percent.The study achieved the purpose of the comprehensive recovery of valuable metals in the ore and provided the technical support for further development of this mine.%针对内蒙古某低品位银多金属硫化矿,应用无毒浮选药剂,采用铜铅混选分离-再选锌浮选工艺流程,产出了可供销售的铜精矿、铅精矿和锌精矿产品,并取得了铜回收率50.39%、铅回收率70.08%、锌回收率79.09%、银在铜精矿和铅精矿中总回收率为65.47%的指标,达到了全面回收矿石中有价金属的目的,为该矿山的进一步开发提供了技术支持。

  13. Atomic Force Microscopy of the fungi-mineral interface: applications in mineral dissolution, weathering and biogeochemistry.

    Science.gov (United States)

    McMaster, Terence J

    2012-08-01

    The interaction between mycorrhizal fungi and minerals is of fundamental importance in affecting the geochemical carbon cycle and CO(2) concentration in the atmosphere, alongside roles in soil creation and the release of nutrients. The symbiosis between the fungi and the plant, supported by photosynthesis in the host plant, has as one of its key features the interfacial zone where mineral and fungi come into contact. At this interface, the organism exudes a complex mixture of organic acids, chelating molecules, protons, and extracellular polysaccharide. In this review, examples will be given of recent Atomic Force Microscopy experiments to monitor the colonization of phyllosilicate minerals in sterile controlled microcosm environments containing only tree seedlings, mineral chips and mycorrhizal fungi. The surface activity of the colonizing fungal hyphae is extensive and complex. In complementary experiments involving exposure of minerals surfaces to single organic acids, it has been possible to monitor dissolution at the unit cell level and to extract activation energies for specific dissolution processes, for example 49 kJ mol(-1) for 100 mM oxalic acid acting upon a biotite sample. The link between these simpler model experiments and the whole microcosm studies is illustrated partly by observations of fungal-colonized mineral surfaces from microcosms after careful removal of the organism and biolayer. These mineral surfaces give clear indications of basal plane modification and fungal weathering. Copyright © 2012. Published by Elsevier Ltd.

  14. Twenty-Sixth Symposium (International) on Combustion, Volume 1.

    Science.gov (United States)

    1997-04-01

    Fundamental Aspects of Combustion, Oxford University Press, New York, 1993, p. 81. 12. Ross, H. D., Miller, F. J., Schiller, D. N., and Sirig- nano , W...Mech. 48:547-591 (1971). 2. Lazaro , B. J. and Lasheras, J. C, Phys. Fluids 1:1035 (1989). 3. Kiger, K. T. and Lasheras, J. C, Twenty-Fifth Sympo

  15. Proceedings of the Twenty Second Nordic Seminar on Computational Mechanics

    DEFF Research Database (Denmark)

    This book contains the proceedings of the Twenty Second Nordic Seminar on Computational Mechanics (NSCM22), taking event 22-23 October 2009 at Aalborg University, Denmark. The papers presented at the Optimization Seminar in Honour of Niels Olhoff, held 21 October 2009 at Aalborg University, Denmark...

  16. The Work Place of the Early Twenty-First Century.

    Science.gov (United States)

    Brown, James M.

    1991-01-01

    Major issues affecting the workplace of the twenty-first century include productivity growth, globalization, resistance to change, worker alienation, and telecommunications. Opposing views of technology are that (1) it will improve the economy and create jobs or (2) the majority of new jobs will not require high skills. (SK)

  17. Educators Guide to Free Filmstrips. Twenty-Third Edition.

    Science.gov (United States)

    Horkheimer, Mary Foley, Comp.; Diffor, John C., Comp.

    A total of 453 titles of filmstrips, slide sets, and sets of transparencies available free of charge to educators are listed in this guide. More than 20,000 separate frames are offered from 95 sources. Twenty of the filmstrips may be retained permanently by the borrower. The films cover topics in the fields of accident prevention, aerospace…

  18. Membership, Belonging, and Identity in the Twenty-First Century

    Science.gov (United States)

    Motteram, Gary

    2016-01-01

    This article takes a case study approach to exploring membership, belonging, and identity amongst English language teachers in the twenty-first century. It explores findings from two membership surveys conducted for the International Association of Teachers of English as a Foreign Language (IATEFL), and considers the impact of recommendations…

  19. Tall Fescue for the Twenty-first Century

    Science.gov (United States)

    Tall Fescue for the Twenty-first Century is a comprehensive monograph by experts from around the world about the science of tall fescue [Lolium arundinaceum (Schreb.) Darbysh. = Schedonorus arundinaceus (Schreb.) Dumort., formerly Fes¬tuca arundinacea Schreb. var. arundinacea] and its applications. ...

  20. Powering into the twenty-first century [Singapore Power Limited

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1997-07-01

    To meet the challenges of the twenty-first century power industry, Singapore Power was incorporated as a commercial entity in October 1995. As the leading energy company in Singapore, SP continues to invest heavily in infrastructure development to improve its service efficiency and reliability, and to maintain its reputation as one of the world`s best power suppliers. (UK)

  1. Afterword: Victorian Sculpture for the Twenty-First Century

    Directory of Open Access Journals (Sweden)

    David J. Getsy

    2016-06-01

    Full Text Available Commenting on the directions proposed by this issue of '19', the afterword discusses the broad trends in twenty-first century studies of Victorian sculpture and the opportunity for debate arising from the first attempt at a comprehensive exhibition.

  2. Membership, Belonging, and Identity in the Twenty-First Century

    Science.gov (United States)

    Motteram, Gary

    2016-01-01

    This article takes a case study approach to exploring membership, belonging, and identity amongst English language teachers in the twenty-first century. It explores findings from two membership surveys conducted for the International Association of Teachers of English as a Foreign Language (IATEFL), and considers the impact of recommendations…

  3. Blended Instruction: The Roaring Twenties Meets Coursesites.com

    Science.gov (United States)

    Waldron, Diane L.

    2014-01-01

    The action research study described in this report outlines the design and implementation of a unit of blended instruction in a traditional high school English classroom. Twenty technical high school students in an 11th grade Honors English class engaged in a variety of internet-based activities in conjunction with traditional learning activities…

  4. Twenty-One: a baseline for multilingual multimedia retrieval

    NARCIS (Netherlands)

    Jong, de Franciska; Hiemstra, Djoerd; Jong, de Franciska; Netter, Klaus

    1998-01-01

    In this paper we will give a short overview of the ideas underpinning the demonstrator developed within the EU-funded project Twenty-One; this system provides for the disclosure of information in a heterogeneous document environment that includes documents of different types and languages. As part o

  5. Twenty years of physics at MAMI -What did it mean?

    Energy Technology Data Exchange (ETDEWEB)

    Mecking, B.A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2006-05-15

    The development over the last twenty years of the physics program and the experimental facilities at the Mainz Microtron MAMI will be reviewed. Ground-breaking contributions have been made to the development of experimental techniques and to our understanding of the structure of nucleons and nuclei. (orig.)

  6. The Presidential Platform on Twenty-First Century Education Goals

    Science.gov (United States)

    Tichnor-Wagner, Ariel; Socol, Allison Rose

    2016-01-01

    As social and economic problems change, so do the goals of education reformers. This content analysis of presidential debates transcripts, state of the union addresses, and education budgets from 2000 to 2015 reveals the ways in which presidents and presidential candidates have framed education goals thus far in the twenty-first century. Using…

  7. Twenty years of physics at MAMI --What did it mean?

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard Mecking

    2006-06-01

    The development over the last twenty years of the physics program and the experimental facilities at the Mainz Microtron MAMI will be reviewed. Ground-breaking contributions have been made to the development of experimental techniques and to our understanding of the structure of nucleons and nuclei.

  8. The Work Place of the Early Twenty-First Century.

    Science.gov (United States)

    Brown, James M.

    1991-01-01

    Major issues affecting the workplace of the twenty-first century include productivity growth, globalization, resistance to change, worker alienation, and telecommunications. Opposing views of technology are that (1) it will improve the economy and create jobs or (2) the majority of new jobs will not require high skills. (SK)

  9. Twenty-One: a baseline for multilingual multimedia retrieval

    NARCIS (Netherlands)

    Unknown, [Unknown; Hiemstra, Djoerd; de Jong, Franciska M.G.; Netter, Klaus

    1998-01-01

    In this paper we will give a short overview of the ideas underpinning the demonstrator developed within the EU-funded project Twenty-One; this system provides for the disclosure of information in a heterogeneous document environment that includes documents of different types and languages. As part o

  10. Digital earth applications in the twenty-first century

    NARCIS (Netherlands)

    de By, R.A.; Georgiadou, P.Y.

    2014-01-01

    In these early years of the twenty-first century, we must look at how the truly cross-cutting information technology supports other innovations, and how it will fundamentally change the information positions of government, private sector and the scientific domain as well as the citizen. In those

  11. Adsorption of RNA on mineral surfaces and mineral precipitates

    Science.gov (United States)

    Biondi, Elisa; Furukawa, Yoshihiro; Kawai, Jun

    2017-01-01

    The prebiotic significance of laboratory experiments that study the interactions between oligomeric RNA and mineral species is difficult to know. Natural exemplars of specific minerals can differ widely depending on their provenance. While laboratory-generated samples of synthetic minerals can have controlled compositions, they are often viewed as "unnatural". Here, we show how trends in the interaction of RNA with natural mineral specimens, synthetic mineral specimens, and co-precipitated pairs of synthetic minerals, can make a persuasive case that the observed interactions reflect the composition of the minerals themselves, rather than their being simply examples of large molecules associating nonspecifically with large surfaces. Using this approach, we have discovered Periodic Table trends in the binding of oligomeric RNA to alkaline earth carbonate minerals and alkaline earth sulfate minerals, where those trends are the same when measured in natural and synthetic minerals. They are also validated by comparison of co-precipitated synthetic minerals. We also show differential binding of RNA to polymorphic forms of calcium carbonate, and the stabilization of bound RNA on aragonite. These have relevance to the prebiotic stabilization of RNA, where such carbonate minerals are expected to have been abundant, as they appear to be today on Mars.

  12. Carbon and nitrogen mineralization are decoupled in organo-mineral fractions

    Science.gov (United States)

    Bimüller, Carolin; Mueller, Carsten W.; von Lützow, Margit; Kreyling, Olivia; Kölbl, Angelika; Haug, Stephan; Schloter, Michael; Kögel-Knabner, Ingrid

    2015-04-01

    characterizing soil fractions where organic matter is mainly stabilized by spatial inaccessibility and by organo-mineral interactions. The specific interactions of both carbon and nitrogen containing components with the mineral matrix strongly modulate the mineralization dynamics, leading to a decoupling of these processes.

  13. [MICROBIAL DESTRUCTION MINERAL (OIL) MOTOR OIL].

    Science.gov (United States)

    Homenko, L A; Nogina, T M

    2015-01-01

    In a review information is presented about composition of mineral motor oils and their negative impact on the environment and the ability of microorganisms, in particular actinobacteria, to assimilate hydrocarbon oil components. The role of bacteria is described in the process of cleaning up polluted environments motor oils and the prospect of their use in biotechnology, environmental clean-up of these pollutants.

  14. Organic matter mineralization in marine systems

    NARCIS (Netherlands)

    Middelburg, J.J.; Vlug, T.; Van der Nat, F.J.

    1993-01-01

    Many of the reactions and biogeochemical processes that occur in the marine environment are related directly or indirectly to the mineralization of organic matter. Decomposition of organic matter is responsible for the recycling of essential nutrients, for the oxygen balance of the ocean and its sed

  15. Organic matter mineralization in marine systems

    NARCIS (Netherlands)

    Middelburg, J.J.; Vlug, T.; Van der Nat, F.J.

    1993-01-01

    Many of the reactions and biogeochemical processes that occur in the marine environment are related directly or indirectly to the mineralization of organic matter. Decomposition of organic matter is responsible for the recycling of essential nutrients, for the oxygen balance of the ocean and its

  16. Mineral scale management. Part II, Fundamental chemistry

    Science.gov (United States)

    Alan W. Rudie; Peter W. Hart

    2006-01-01

    The mineral scale that deposits in digesters and bleach plants is formed by a chemical precipitation process.As such, it is accurately modeled using the solubility product equilibrium constant. Although solubility product identifies the primary conditions that must be met for a scale problem to exist, the acid-base equilibria of the scaling anions often control where...

  17. Marine minerals: The Indian perspective

    Digital Repository Service at National Institute of Oceanography (India)

    Gujar, A.R.; Nath, B.N.; Banerjee, R.

    The sea floor of the continental margins of India is covered by a wide variety of terrigenous, biogenous, and chemogenous mineral deposits. Terrigenous heavy mineral placers containing ilmenite, magnetite, monazite, zircon, and rutile are reported...

  18. Unmixing of spectrally similar minerals

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2009-01-01

    Full Text Available -bearing oxide/hydroxide/sulfate minerals in complex mixtures be obtained using hyperspectral data? Debba (CSIR) Unmixing of spectrally similar minerals MERAKA 2009 3 / 18 Method of spectral unmixing Old method: problem Linear Spectral Mixture Analysis (LSMA...

  19. Agricultural Minerals Operations - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer includes agricultural minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  20. Construction Minerals Operations - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer includes construction minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  1. Mineral commodity profiles: nitrogen

    Science.gov (United States)

    Kramer, Deborah A.

    2004-01-01

    Overview -- Nitrogen (N) is an essential element of life and a part of all animal and plant proteins. As a part of the DNA and RNA molecules, nitrogen is an essential constituent of each individual's genetic blueprint. As an essential element in the chlorophyll molecule, nitrogen is vital to a plant's ability to photosynthesize. Some crop plants, such as alfalfa, peas, peanuts, and soybeans, can convert atmospheric nitrogen into a usable form by a process referred to as 'fixation.' Most of the nitrogen that is available for crop production, however, comes from decomposing animal and plant waste or from commercially produced fertilizers. Commercial fertilizers contain nitrogen in the form of ammonium and/or nitrate or in a form that is quickly converted to the ammonium or nitrate form once the fertilizer is applied to the soil. Ammonia is generally the source of nitrogen in fertilizers. Anhydrous ammonia is commercially produced by reacting nitrogen with hydrogen under high temperatures and pressures. The source of nitrogen is the atmosphere, which is almost 80 percent nitrogen. Hydrogen is derived from a variety of raw materials, which include water, and crude oil, coal, and natural gas hydrocarbons. Nitrogen-based fertilizers are produced from ammonia feedstocks through a variety of chemical processes. Small quantities of nitrates are produced from mineral resources principally in Chile. In 2002, anhydrous ammonia and other nitrogen materials were produced in more than 70 countries. Global ammonia production was 108 million metric tons (Mt) of contained nitrogen. With 28 percent of this total, China was the largest producer of ammonia. Asia contributed 46 percent of total world ammonia production, and countries of the former U.S.S.R. represented 13 percent. North America also produced 13 percent of the total; Western Europe, 9 percent; the Middle East, 7 percent; Central America and South America, 5 percent; Eastern Europe, 3 percent; and Africa and Oceania

  2. Geoelectrical Signatures Of Microbial Stimulated Mineralization

    Science.gov (United States)

    Personna, Y. R.; Ntarlagiannis, D.; Slater, L.; O Brien, M.; Hubbard, S.; Williams, K. H.

    2007-05-01

    Bioremediation techniques are commonly utilized to address soil and groundwater contamination due to acid- mine drainage, industrial sources, and government nuclear weapon programs. One critical component of these efforts is the real time, spatially accurate monitoring of the remediation processes. For this reason non-invasive high resolution geophysical methods have been employed in the recent years to elucidate system transformations occurring during bioremediation. In our study, we performed laboratory column experiments to investigate the geoelectrical response of microbe-mediated iron sulfide (FeS) precipitation accompanying stimulated sulfate-reduction; a bioremediation technique currently utilized for the sequestration of heavy metals in the subsurface. In order to monitor the biomineralization process, we used two geoelectrical methods - induced polarization (IP) and self-potential (SP) - in conjunction with conventional geochemical measurements. The IP data showed significant anomalies associated with ongoing FeS mineralization accompanying microbial activity. The magnitude of the IP response can be considered a proxy for the mass of minerals accumulating in the pore space and may provide insight into the aggregation state of the mineralization. Additionally, strong SP anomalies developed during the mineralization as a result of the continuous redox state changes following the microbial induced mineral formation. Visibly black precipitates accumulated with the column indicating FeS precipitation, and high H2S content confirmed the observed geochemical and geophysical data. Overall, the results suggest that the IP and SP methods can be used to monitor the progress of the microbial induced mineralization process associated with the precipitation of insoluble metal sulfides, and indirectly monitor the microbial activity within the subsurface. These methods can be valuable tools to increase the efficiency of bioremediation techniques.

  3. Understanding Contamination; Twenty Years of Simulating Radiological Contamination

    Energy Technology Data Exchange (ETDEWEB)

    Emily Snyder; John Drake; Ryan James

    2012-02-01

    A wide variety of simulated contamination methods have been developed by researchers to reproducibly test radiological decontamination methods. Some twenty years ago a method of non-radioactive contamination simulation was proposed at the Idaho National Laboratory (INL) that mimicked the character of radioactive cesium and zirconium contamination on stainless steel. It involved baking the contamination into the surface of the stainless steel in order to 'fix' it into a tenacious, tightly bound oxide layer. This type of contamination was particularly applicable to nuclear processing facilities (and nuclear reactors) where oxide growth and exchange of radioactive materials within the oxide layer became the predominant model for material/contaminant interaction. Additional simulation methods and their empirically derived basis (from a nuclear fuel reprocessing facility) are discussed. In the last ten years the INL, working with the Defense Advanced Research Projects Agency (DARPA) and the National Homeland Security Research Center (NHSRC), has continued to develop contamination simulation methodologies. The most notable of these newer methodologies was developed to compare the efficacy of different decontamination technologies against radiological dispersal device (RDD, 'dirty bomb') type of contamination. There are many different scenarios for how RDD contamination may be spread, but the most commonly used one at the INL involves the dispersal of an aqueous solution containing radioactive Cs-137. This method was chosen during the DARPA projects and has continued through the NHSRC series of decontamination trials and also gives a tenacious 'fixed' contamination. Much has been learned about the interaction of cesium contamination with building materials, particularly concrete, throughout these tests. The effects of porosity, cation-exchange capacity of the material and the amount of dirt and debris on the surface are very important factors

  4. Optimization method for quantitative calculation of clay minerals in soil

    Indian Academy of Sciences (India)

    Libo Hao; Qiaoqiao Wei; Yuyan Zhao; Zilong Lu; Xinyun Zhao

    2015-04-01

    Determination of types and amounts for clay minerals in soil are important in environmental, agricultural, and geological investigations. Many reliable methods have been established to identify clay mineral types. However, no reliable method for quantitative analysis of clay minerals has been established so far. In this study, an attempt was made to propose an optimization method for the quantitative determination of clay minerals in soil based on bulk chemical composition data. The fundamental principles and processes of the calculation are elucidated. Some samples were used for reliability verification of the method and the results prove the simplicity and efficacy of the approach.

  5. Discussion on Nontraditional Mineral Resources

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, the authors introduce the concept of nontraditional mineral resources, and pro pose the major system of nontraditional mineral resources, including nontraditional resources, research methods, mining and mineral economics. Then the authors conclude that the research on nontraditional mineral resources is not only significant to satisfication the human needs in the 21st century, but also important to the development of the present geological theory.

  6. Mapping the Mineral Resource Base for Mineral Carbon-Dioxide Sequestration in the Conterminous United States

    Science.gov (United States)

    Krevor, S.C.; Graves, C.R.; Van Gosen, B. S.; McCafferty, A.E.

    2009-01-01

    This database provides information on the occurrence of ultramafic rocks in the conterminous United States that are suitable for sequestering captured carbon dioxide in mineral form, also known as mineral carbon-dioxide sequestration. Mineral carbon-dioxide sequestration is a proposed greenhouse gas mitigation technology whereby carbon dioxide (CO2) is disposed of by reacting it with calcium or magnesium silicate minerals to form a solid magnesium or calcium carbonate product. The technology offers a large capacity to permanently store CO2 in an environmentally benign form via a process that takes little effort to verify or monitor after disposal. These characteristics are unique among its peers in greenhouse gas disposal technologies. The 2005 Intergovernmental Panel on Climate Change report on Carbon Dioxide Capture and Storage suggested that a major gap in mineral CO2 sequestration is locating the magnesium-silicate bedrock available to sequester the carbon dioxide. It is generally known that silicate minerals with high concentrations of magnesium are suitable for mineral carbonation. However, no assessment has been made in the United States that details their geographical distribution and extent, nor has anyone evaluated their potential for use in mineral carbonation. Researchers at Columbia University and the U.S. Geological Survey have developed a digital geologic database of ultramafic rocks in the conterminous United States. Data were compiled from varied-scale geologic maps of magnesium-silicate ultramafic rocks. The focus of our national-scale map is entirely on ultramafic rock types, which typically consist primarily of olivine- and serpentine-rich rocks. These rock types are potentially suitable as source material for mineral CO2 sequestration.

  7. Aggregates from mineral wastes

    Directory of Open Access Journals (Sweden)

    Baic Ireneusz

    2016-01-01

    Full Text Available The problem concerning the growing demand for natural aggregates and the need to limit costs, including transportation from remote deposits, cause the increase in growth of interest in aggregates from mineral wastes as well as in technologies of their production and recovery. The paper presents the issue related to the group of aggregates other than natural. A common name is proposed for such material: “alternative aggregates”. The name seems to be fully justified due to adequacy of this term because of this raw materials origin and role, in comparison to the meaning of natural aggregates based on gravel and sand as well as crushed stones. The paper presents characteristics of the market and basic application of aggregates produced from mineral wastes, generated in the mining, power and metallurgical industries as well as material from demolished objects.

  8. Rock and mineral magnetism

    CERN Document Server

    O’Reilly, W

    1984-01-01

    The past two decades have witnessed a revolution in the earth sciences. The quantitative, instrument-based measurements and physical models of. geophysics, together with advances in technology, have radically transformed the way in which the Earth, and especially its crust, is described. The study of the magnetism of the rocks of the Earth's crust has played a major part in this transformation. Rocks, or more specifically their constituent magnetic minerals, can be regarded as a measuring instrument provided by nature, which can be employed in the service of the earth sciences. Thus magnetic minerals are a recording magnetometer; a goniometer or protractor, recording the directions of flows, fields and forces; a clock; a recording thermometer; a position recorder; astrain gauge; an instrument for geo­ logical surveying; a tracer in climatology and hydrology; a tool in petrology. No instrument is linear, or free from noise and systematic errors, and the performance of nature's instrument must be assessed and ...

  9. Iodine mineral waters

    Directory of Open Access Journals (Sweden)

    Iluta Alexandru

    2011-11-01

    Full Text Available Iodine mineral waters are found especially in sub-Carpathian region, also in regions with Salif deposits. Waters are currently used iodine in drinking cure for chaps and Basedow. Are also indicated in balneology. Iodine water containing at least 1 mg L, there is pure iodine is usually given the nature of other types of mineral waters further: sodium chlorinated water (Bazna (50-70 mg iodine / l, Baile Govora (50 - 70 mg / l, Bălţăteşti (4-5 mg / l, salted Monteoru (30 mg / l, mine water mixed alkaline chlorination, sulphate, which are indicated for crenoterapie (hypo or isotonic to the bathrooms Olăneşti or Călimăneşti-Căciulata.

  10. Mineral CO2 sequestration by steel slag carbonation

    NARCIS (Netherlands)

    Huijgen, W.J.J.; Comans, R.N.J.

    2005-01-01

    Mineral CO2 sequestration, i.e., carbonation of alkaline silicate Ca/Mg minerals, analogous to natural weathering processes, is a possible technology for the reduction of carbon dioxide emissions to the atmosphere. In this paper, alkaline Ca-rich industrial residues are presented as a possible feeds

  11. Surface characterization of bacterial cells relevant to the mineral industry

    NARCIS (Netherlands)

    Sharma, PK; Rao, KH

    2005-01-01

    Bacteria belonging to the Acidithiobacilli group are widely used in the mineral processing industry in bioleaching and biobeneficiation operations. Paenibacillus polymyxa has also found application in biobeneficiation studies. Microbial adhesion to mineral surface is an essential step,for both biobe

  12. Coastal placer minerals

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Gujar, A.R.

    by mechanical concentration and natural gravity separation of mineral particles derived from weathered rocks. The formation of placers requires factors such as: climate, source rock, weathering, transport, deposition, concentration, high specific gravity... and transport of the rocks. For example, in cold and glaciated regions, there would be limited physical weathering and less concentration and more dispersion of the weathered material and placers would not FE AT U R E FE AT U R E A RT IC LE form...

  13. Mineral metabolism in cats

    OpenAIRE

    Pineda Martos, Carmen María

    2014-01-01

    The present Doctoral Thesis wa metabolism in the feline species. Through a series of studies, the relationship between calcium metabolism and the main hormones involved in it has been determined metabolism during the juvenile stage of growing cats effects linked to feeding calculolytic diets on feline mineral metabolism. The first part of the work was aimed the quantification of intact (I-PTH) and whole PTH) and to characterize the dynamics of PTH secretion, including ...

  14. Dynamic Model of Mineralization Enrichment and Its Applications

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper studies the chaos dynamic mechanism of the migration, enrichment and mineralization of elements in the crust. The research shows that the interaction of the nonlinear process in the geological environment is an essential factor for the uneven distribution of elements and the mineralization in the crust, determining the element contents and the fractal structure of the distribution of the large- and small-sized mineral deposits. The logistic map is a better mathematical model describing the behavior of the chaos dynamic. The parameter μ, i.e. , the mineralizing potential, is employed to divide the region into non-mineralization region or mineralization region.The value of the parameterμ in model (3) with true data (in Xinjiang Au tomatio region, China) is obtained with the statistical method. The forecasting results are generally in accordance with those obtained with other methods, for example, with the characteristic analysis.

  15. Physicochemical characterization of mineral deposits in human ligamenta flava.

    Science.gov (United States)

    Orzechowska, Sylwia; Wróbel, Andrzej; Kozieł, Marcin; Łasocha, Wiesław; Rokita, Eugeniusz

    2017-04-07

    The aim of our study was the detailed characterization of calcium deposits in ligamenta flava. The use of microcomputed tomography allowed extending the routine medical investigations to characterize mineral grains in the microscopic scale. A possible connection between spinal stenosis and ligament mineralization was investigated. The studies were carried out on 24 surgically removed ligamentum flavum samples divided into control and stenosis groups. Physicochemical characterization of the inorganic material was performed using X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy. The minerals were present in 14 of 24 ligament samples, both in stenosis and control groups. The inorganic substance constitutes on average ~0.1% of the sample volume. The minerals are scattered in the soft tissue matrix without any regular pattern. It was confirmed that minerals possess an internal structure and consist of the organic material and small inorganic grains mixture. The physicochemical analyses show that the predominant crystalline phase was hydroxyapatite (HAP). In the stenosis group calcium pyrophosphate dehydrate (CPPD) was identified. Both structures were never present in a single sample. Two different crystal structures suggest two independent processes of mineralization. The formation of CPPD may be treated as a more intense process since CPPD minerals are characterized by bigger values of the structural parameters and higher density than HAP deposits. The formation of HAP minerals is a soft tissue degeneration process that begins, in some cases, at early age or may not occur at all. Various density and volume of mineral grains indicate that the mineralization process does not occur in a constant environment and proceeds with various speeds. The formation of minerals in ligamenta flava is not directly associated with diagnosed spinal canal stenosis.

  16. Polymer-mediated mesoscale mineralization

    Institute of Scientific and Technical Information of China (English)

    CHEN ShaoFeng; YU ShuHong

    2009-01-01

    Polymer-controlled mineralization in aqueous solution or in a mixed solvent media, as well as its com-bination with the interface of air-water can lead to the formation of minerals with unique structures and morphologies, which sheds light on the possibility to mimic the detailed structures of the natural min-erals.

  17. Definitions of Health Terms: Minerals

    Science.gov (United States)

    ... this page: https://medlineplus.gov/definitions/mineralsdefinitions.html Definitions of Health Terms : Minerals To use the sharing features on ... of the minerals that you need. Find more definitions on Fitness | General Health | Minerals | Nutrition | Vitamins Antioxidants Antioxidants are substances that ...

  18. Refractory Minerals in Henan Province

    Institute of Scientific and Technical Information of China (English)

    JIN Qinguo; LI Jing; LIU Jiehua; LIU Yanjun

    2004-01-01

    Henan province is very rich in refractory minerals of many varieties including silica, dolomite, graphite,pearlite, sepiolite, olivine, and sillimanite group minerals, besides the abundant reserves of fireclay and bauxite,which lay a good foundation for the development of the refractories industry of the province. The paper introduces the reserves, distribution and character of the refractory minerals in Henan province.

  19. RESEARCH OF PROVIDING INFRASTRUCTURE OF MINERAL FERTILIZERS TO AGRICULTURAL CONSUMERS

    Directory of Open Access Journals (Sweden)

    Philatov S. K.

    2015-04-01

    Full Text Available Currently, for producers of mineral fertilizers one of the main tasks is the process of creating a supply chain of mineral fertilizers delivery to agricultural consumers, running on a «Just-in-time» way. The effective operation of such a supply chain has to be influenced by many factors, including: the technology of agricultural production, seasonality of agricultural work, the structure of the distribution channel of mineral fertilizers, the geographical features of consumers, the availability of appropriate infrastructure, etc. Critical elements of the infrastructure are warehouses and equipment for storage of mineral fertilizers, as well as the road network. For example, farms in the Rostov region were analyzed for the infrastructure necessary for the successful supply of mineral fertilizer agricultural consumers. It was found that the capacity of warehouses and facilities for the storage of mineral fertilizers and distribution of cultivated areas between agricultural enterprises of different size are diametrically opposed. The process of delivery of mineral fertilizers need to be developed taking into account the shortage or complete lack of storage capacity for their storage, especially for small enterprises. The existing road network, with paved allows us to deliver of mineral fertilizers virtually all consumers by road transport. This dictates the feasibility of delivery of mineral fertilizers to consumers by road transport in soft containers (Big Bags, allowing the storage in the open air

  20. Proceedings of the 36. annual meeting of the Canadian Mineral Processors

    Energy Technology Data Exchange (ETDEWEB)

    Abols, J. [Gekko Systems, Vancouver, BC (Canada)] (comp.)

    2004-07-01

    This conference provided an opportunity for professionals and students in the metallurgical and minerals processing industries to gain insight into how metallurgical projects can be successfully designed, engineered and commissioned. It provides information on mineral deposits, ore controls, mineralogy, geochemistry, mineral processing and beneficiation. The presentations covered a wide range of issues regarding mineral processing such as plant operations and improvements, process control and simulation, industrial minerals, applied mineralogy, effluent treatment and new technology and predictive tools. This conference featured 38 presentations, of which 4 have been indexed separately for inclusion in this database. refs., tabs., figs.