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Sample records for accompanying mineral crystal

  1. 30 CFR 250.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What mineral resource conservation information must accompany the DPP or DOCD? 250.246 Section 250.246 Mineral Resources MINERALS MANAGEMENT SERVICE... Coordination Documents (docd) § 250.246 What mineral resource conservation information must accompany the...

  2. CRYSTAL CHEMISTRY OF HYDROUS MINERALS

    SciTech Connect

    Y. ZHAO; ET AL

    2001-02-01

    Hydrogen has long been appreciated for its role in geological processes of the Earth's crust. However, its role in Earth's deep interior has been neglected in most geophysical thinking. Yet it is now believed that most of our planet's hydrogen may be locked up in high pressure phases of hydrous silicate minerals within the Earth's mantle. This rocky interior (approximately 7/8 of Earth's volume) is conjectured to contain 1-2 orders of magnitude more water than the more obvious oceans (the ''hydrosphere'') and atmosphere. This project is aimed at using the capability of neutron scattering from hydrogen to study the crystal chemistry and stability of hydrogen-bearing minerals at high pressures and temperatures. At the most basic level this is a study of the atomic position and hydrogen bond itself. We have conducted experimental runs on hydrous minerals under high pressure and high temperature conditions. The crystallographic structure of hydrous minerals at extreme conditions and its structural stability, and hydrogen bond at high P-T conditions are the fundamental questions to be addressed. The behavior of the hydrous minerals in the deep interior of the Earth has been discussed.

  3. Crystals: animal, vegetable or mineral?

    PubMed Central

    Hyde, Stephen T.

    2015-01-01

    The morphologies of biological materials, from body shapes to membranes within cells, are typically curvaceous and flexible, in contrast to the angular, facetted shapes of inorganic matter. An alternative dichotomy has it that biomolecules typically assemble into aperiodic structures in vivo, in contrast to inorganic crystals. This paper explores the evolution of our understanding of structures across the spectrum of materials, from living to inanimate, driven by those naive beliefs, with particular focus on the development of crystallography in materials science and biology. The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries. Our current understanding, driven largely by detailed exploration of biomolecular structures at the sub-cellular level initiated by Bernal and Astbury in the 1930s, and more recent explorations of sterile soft matter, makes it clear that this is a false dichotomy. For example, liquid crystals and other soft materials are common to both living and inanimate materials. The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter. In addition to the philosophical relevance of this perspective, there are important ramifications for science. For example, the debates surrounding extra-terrestrial life, the oldest terrestrial fossils and consequent dating of the emergence of life on the Earth rests to some degree on prejudices inferred from the supposed dichotomy between life-forms and the rest. PMID:26464788

  4. Experimental dynamic metamorphism of mineral single crystals

    USGS Publications Warehouse

    Kirby, S.H.; Stern, L.A.

    1993-01-01

    This paper is a review of some of the rich and varied interactions between non-hydrostatic stress and phase transformations or mineral reactions, drawn mainly from results of experiments done on mineral single crystals in our laboratory or our co-authors. The state of stress and inelastic deformation can enter explicitly into the equilibrium phase relations and kinetics of mineral reactions. Alternatively, phase transformations can have prominent effects on theology and on the nature of inelastic deformation. Our examples represent five types of structural phase changes, each of which is distinguished by particular mechanical effects. In increasing structural complexity, these include: (1) displacive phase transformations involving no bond-breaking, which may produce anomalous brittle behavior. A primary example is the a-?? quartz transition which shows anomalously low fracture strength and tertiary creep behavior near the transition temperature; (2) martensitic-like transformations involving transformation strains dominated by shear deformation. Examples include the orthoenstatite ??? clinoenstatite and w u ??rtzite ??? sphalerite transformations; (3) coherent exsolution or precipitation of a mineral solute from a supersaturated solid-solution, with anisotropy of precipitation and creep rates produced under nonhydrostatic stress. Examples include exsolution of corundum from MgO ?? nAl2O3 spinels and Ca-clinopyroxene from orthopyroxene; (4) order-disorder transformations that are believed to cause anomalous plastic yield strengthening, such as MgO - nAl2O3 spinels; and (5) near-surface devolatilization of hydrous silicate single-crystals that produces a fundamental brittleness thought to be connected with dehydration at microcracks at temperatures well below nominal macroscopic dehydration temperatures. As none of these interactions between single-crystal phase transformations and non-hydrostatic stress is understood in detail, this paper serves as a challenge to

  5. Inverse Slip Accompanying Twinning and Detwinning during Cyclic Loading of Magnesium Single Crystal

    DOE PAGES

    Yu, Qin; Wang, Jian; Jiang, Yanyao

    2013-01-01

    In situ , observation of twinning and detwinning in magnesium single crystals during tension-compression cyclic loading was made using optical microscopy. A quantitative analysis of plastic strain indicates that twinning and detwinning experience two stages, low and high work hardening de-twinning, and pure re-twinning and fresh twinning combined with retwinning. Slip is always activated. For the first time, inverse slip accompanying with pure retwinning and high work hardening detwinning was experimentally identified, which provides insights in better understanding of the activity of twining, detwinning, and slips.

  6. The emission of atoms and molecules accompanying fracture of single-crystal MgO

    NASA Technical Reports Server (NTRS)

    Dickinson, J. T.; Jensen, L. C.; Mckay, M. R.; Freund, F.

    1986-01-01

    The emission of particles due to deformation and fracture of materials has been investigated. The emission of electrons (exoelectron emission), ions, neutral species, photons (triboluminescence), as well as long wavelength electromagnetic radiation was observed; collectively these emissions are referred to as fractoemission. This paper describes measurements of the neutral emission accompanying the fracture of single-crystal MgO. Masses detected are tentatively assigned to the emission of H2, CH4, H2O, CO, O2, CO2, and atomic Mg. Other hydrocarbons are also observed. The time dependencies of some of these emissions relative to fracture are presented for two different loading conditions.

  7. 30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What mineral resource conservation information... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

  8. 30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What mineral resource conservation information... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

  9. 30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What mineral resource conservation information... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

  10. 30 CFR 250.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... information, as applicable, must accompany your DPP or DOCD: (a) Technology and reservoir engineering practices and procedures. A description of the technology and reservoir engineering practices and procedures... you will use to ensure optimum recovery of oil and gas or sulphur. (c) Reservoir development....

  11. Automated mineral identification algorithm using optical properties of crystals

    NASA Astrophysics Data System (ADS)

    Aligholi, Saeed; Khajavi, Reza; Razmara, Morteza

    2015-12-01

    A method has been developed to automatically characterize the type of mineral phases by means of digital image analysis using optical properties of crystals. The method relies on microscope automation, digital image acquisition, image processing and analysis. Two hundred series of digital images were taken from 45 standard thin sections using a digital camera mounted on a conventional microscope and then transmitted to a computer. CIELab color space is selected for the processing, in order to effectively employ its well-defined color difference metric for introducing appropriate color-based feature. Seven basic optical properties of minerals (A. color; B. pleochroism; C. interference color; D. birefringence; E. opacity; F. isotropy; G. extinction angle) are redefined. The Local Binary Pattern (LBP) operator and modeling texture is integrated in the Mineral Identification (MI) scheme to identify homogeneous regions in microscopic images of minerals. The accuracy of mineral identification using the method was %99, %98, %96 and %95 for biotite, hornblende, quartz and calcite minerals, respectively. The method is applicable to other minerals and phases for which individual optical properties of crystals do not provide enough discrimination between the relevant phases. On the basis of this research, it can be concluded that if the CIELab color space and the local binary pattern (LBP) are applied, it is possible to recognize the mineral samples with the accuracy of more than 98%.

  12. Mineral resource of the month: cultured quartz crystal

    USGS Publications Warehouse

    ,

    2008-01-01

    The article presents information on cultured quartz crystals, a mineral used in mobile phones, computers, clocks and other devices controlled by digital circuits. Cultured quartz, which is synthetically produced in large pressurized vessels known as autoclaves, is useful in electronic circuits for precise filtration, frequency control and timing for consumer and military use. Several ingredients are used in producing cultured quartz, including seed crystals, lascas, a solution of sodium hydroxide or sodium carbonate, lithium salts and deionized water.

  13. Phylogenetic significance of composition and crystal morphology of magnetosome minerals

    PubMed Central

    Pósfai, Mihály; Lefèvre, Christopher T.; Trubitsyn, Denis; Bazylinski, Dennis A.; Frankel, Richard B.

    2013-01-01

    Magnetotactic bacteria (MTB) biomineralize magnetosomes, nano-scale crystals of magnetite or greigite in membrane enclosures that comprise a permanent magnetic dipole in each cell. MTB control the mineral composition, habit, size, and crystallographic orientation of the magnetosomes, as well as their arrangement within the cell. Studies involving magnetosomes that contain mineral and biological phases require multidisciplinary efforts. Here we use crystallographic, genomic and phylogenetic perspectives to review the correlations between magnetosome mineral habits and the phylogenetic affiliations of MTB, and show that these correlations have important implications for the evolution of magnetosome synthesis, and thus magnetotaxis. PMID:24324461

  14. The Alaskan mineral resource assessment program; background information to accompany folio of geologic and mineral resource maps of the Nabesna Quadrangle, Alaska

    USGS Publications Warehouse

    Richter, Donald H.; Albert, N.R.D.; Barnes, D.F.; Griscom, Andrew; Marsh, S.P.; Singer, D.A.

    1975-01-01

    The Nabesna quadrangle in south-central Alaska is the first of the l:250,000-scale Alaskan quadrangles to be investigated by an interdisciplinary research team in order to furnish a mineral resource assessment of the State. The assessment of the 17,600-km 2 16,800-mi21 quadrangle is based on field and laboratory investigations of the geology, geochemistry, geophysics, and satellite imagery. The results of the investigations are published as a folio of maps, diagrams, and accompanying discussions. This report provides background information on the investigations and integrates the published components of the resource assessment. A comprehensive bibliography cites both specific and general references to the geology and mineral deposits of the Nabesna quadrangle.

  15. Investigation and analysis of asbestos fibers and accompanying minerals in biological materials.

    PubMed

    Le Bouffant, L

    1974-12-01

    A method is described for isolating asbestos fibers contained in biological tissues. It consists in incinerating the biological material in activated oxygen at 150 degrees C, and attacking the ash by 1N HC1 for 18 hr. The residue is then filtered on a membrane covered with a carbon film. Electron microscope examination of the deposit makes it possible to determine fiber concentrations when the weight or volume of primary material is known, and to make size analyses. By x-ray diffraction, the mineralogical nature of the asbestos is determined by comparison with an aluminum reference diagram. For x-ray diffraction, a micromethod is used, with an ash sample of about 10 mug. These techniques are used for identifying and counting asbestos fibers in small fragments of lungs or other organs. It was found that asbestos fibers generally go along with other minerals which may be abundant. Most fibers found in lung are less than 5 mum long. Counts on lungs of asbestos workers give concentrations often greater than 10(7) particles per gram of dry tissue. The evolution of inhaled chrysotile seems to be different from that of amphiboles. In the case of pleural mesothelioma, a comparison of fibers within the tumor with fibers in the adjacent parenchyma shows only slight differences in the particle sizes, but marked differences in their nature, with a chrysotile enrichment in the pleural zone. Pleural plaques were analyzed in the same way. After decalcification, many small sized asbestos fibers were found. The same technique is now being used for determining ingested particles. A great number of observations concerning fiber counts, their nature and sizes, and the presence of various clays minerals will be necessary to establish the role of the different factors in the formation of lesions caused by the inhalation or the ingestion of asbestos fibers.

  16. Manganese oxide minerals: Crystal structures and economic and environmental significance

    PubMed Central

    Post, Jeffrey E.

    1999-01-01

    Manganese oxide minerals have been used for thousands of years—by the ancients for pigments and to clarify glass, and today as ores of Mn metal, catalysts, and battery material. More than 30 Mn oxide minerals occur in a wide variety of geological settings. They are major components of Mn nodules that pave huge areas of the ocean floor and bottoms of many fresh-water lakes. Mn oxide minerals are ubiquitous in soils and sediments and participate in a variety of chemical reactions that affect groundwater and bulk soil composition. Their typical occurrence as fine-grained mixtures makes it difficult to study their atomic structures and crystal chemistries. In recent years, however, investigations using transmission electron microscopy and powder x-ray and neutron diffraction methods have provided important new insights into the structures and properties of these materials. The crystal structures for todorokite and birnessite, two of the more common Mn oxide minerals in terrestrial deposits and ocean nodules, were determined by using powder x-ray diffraction data and the Rietveld refinement method. Because of the large tunnels in todorokite and related structures there is considerable interest in the use of these materials and synthetic analogues as catalysts and cation exchange agents. Birnessite-group minerals have layer structures and readily undergo oxidation reduction and cation-exchange reactions and play a major role in controlling groundwater chemistry. PMID:10097056

  17. Natural pseudowollastonite: Crystal structure, associated minerals, and geological context

    NASA Astrophysics Data System (ADS)

    Seryotkin, Yurii V.; Sokol, Ella V.; Kokh, Svetlana N.

    2012-03-01

    Pseudowollastonite, an extremely rare constituent of ultrahigh-temperature combustion metamorphic and igneous rocks, has been found as a rock-forming mineral in Ca-rich paralava veins of Nabi Musa fossil mud volcano (Dead Sea area). Pseudowollastonite-bearing paralavas are the products of combustion metamorphism associated with spontaneous burning of methane. The melt began to crystallize at 1480-1500 °C about the ambient pressure. Pseudowollastonite enters two mineral assemblages: (1) rankinite, larnite, nagelschmidtite, wollastonite (1T), gehlenite-rich melilite, Ti-rich andradite, cuspidine, and fluorapatite; (2) parawollastonite (2M), wollastonite (1T), gehlenite-rich melilite, Ti-rich andradite, fluorellestadite. In this study we present the first single-crystal structure determination of natural pseudowollastonite. Pseudowollastonite from Nabi Musa dome is stoichiometric CaSiO3 and belongs to the most widespread four-layer polytype: a = 6.83556(10) Å, b = 11.86962(18) Å, c = 19.6255(3) Å, β = 90.6805(13)°, V = 1592.21(4) Å3, space group C2/c. We argue that pseudowollastonite is so scarce in nature because its formation requires joint action of several uncommon factors: availability of hot melts of T > 1200 °C that bear free calcium but are poor in Mg and Fe (mostly as Fe3 +) and their crystallization in the shallow crust followed by quenching.

  18. Crystal structure control of aluminized clay minerals on the mobility of caesium in contaminated soil environments

    NASA Astrophysics Data System (ADS)

    Dzene, Liva; Ferrage, Eric; Viennet, Jean-Christophe; Tertre, Emmanuel; Hubert, Fabien

    2017-02-01

    Radioactive caesium pollution resulting from Fukushima Dai-ichi and Chernobyl nuclear plant accidents involves strong interactions between Cs+ and clays, especially vermiculite-type minerals. In acidic soil environments, such as in Fukushima area, vermiculite is subjected to weathering processes, resulting in aluminization. The crystal structure of aluminized clays and its implications for Cs+ mobility in soils remain poorly understood due to the mixture of these minerals with other clays and organic matter. We performed acidic weathering of a vermiculite to mimic the aluminization process in soils. Combination of structure analysis and Cs+ extractability measurements show that the increase of aluminization is accompanied by an increase in Cs+ mobility. Crystal structure model for aluminized vermiculite is based on the interstratification of unaltered vermiculite layers and aluminized layers within the same particle. Cs+ in vermiculite layers is poorly mobile, while the extractability of Cs+ is greatly enhanced in aluminized layers. The overall reactivity of the weathered clay (cation exchange capacity, Cs+ mobility) is then governed by the relative abundance of the two types of layers. The proposed layer model for aluminized vermiculite with two coexisting populations of caesium is of prime importance for predicting the fate of caesium in contaminated soil environments.

  19. Crystal structure control of aluminized clay minerals on the mobility of caesium in contaminated soil environments

    PubMed Central

    Dzene, Liva; Ferrage, Eric; Viennet, Jean-Christophe; Tertre, Emmanuel; Hubert, Fabien

    2017-01-01

    Radioactive caesium pollution resulting from Fukushima Dai-ichi and Chernobyl nuclear plant accidents involves strong interactions between Cs+ and clays, especially vermiculite-type minerals. In acidic soil environments, such as in Fukushima area, vermiculite is subjected to weathering processes, resulting in aluminization. The crystal structure of aluminized clays and its implications for Cs+ mobility in soils remain poorly understood due to the mixture of these minerals with other clays and organic matter. We performed acidic weathering of a vermiculite to mimic the aluminization process in soils. Combination of structure analysis and Cs+ extractability measurements show that the increase of aluminization is accompanied by an increase in Cs+ mobility. Crystal structure model for aluminized vermiculite is based on the interstratification of unaltered vermiculite layers and aluminized layers within the same particle. Cs+ in vermiculite layers is poorly mobile, while the extractability of Cs+ is greatly enhanced in aluminized layers. The overall reactivity of the weathered clay (cation exchange capacity, Cs+ mobility) is then governed by the relative abundance of the two types of layers. The proposed layer model for aluminized vermiculite with two coexisting populations of caesium is of prime importance for predicting the fate of caesium in contaminated soil environments. PMID:28233805

  20. Crystal structure control of aluminized clay minerals on the mobility of caesium in contaminated soil environments.

    PubMed

    Dzene, Liva; Ferrage, Eric; Viennet, Jean-Christophe; Tertre, Emmanuel; Hubert, Fabien

    2017-02-24

    Radioactive caesium pollution resulting from Fukushima Dai-ichi and Chernobyl nuclear plant accidents involves strong interactions between Cs(+) and clays, especially vermiculite-type minerals. In acidic soil environments, such as in Fukushima area, vermiculite is subjected to weathering processes, resulting in aluminization. The crystal structure of aluminized clays and its implications for Cs(+) mobility in soils remain poorly understood due to the mixture of these minerals with other clays and organic matter. We performed acidic weathering of a vermiculite to mimic the aluminization process in soils. Combination of structure analysis and Cs(+) extractability measurements show that the increase of aluminization is accompanied by an increase in Cs(+) mobility. Crystal structure model for aluminized vermiculite is based on the interstratification of unaltered vermiculite layers and aluminized layers within the same particle. Cs(+) in vermiculite layers is poorly mobile, while the extractability of Cs(+) is greatly enhanced in aluminized layers. The overall reactivity of the weathered clay (cation exchange capacity, Cs(+) mobility) is then governed by the relative abundance of the two types of layers. The proposed layer model for aluminized vermiculite with two coexisting populations of caesium is of prime importance for predicting the fate of caesium in contaminated soil environments.

  1. The effects of Raman scattering accompanied by the soliton excitation occurring in molecular crystals

    NASA Astrophysics Data System (ADS)

    Pang, X. F.

    2001-06-01

    A theoretical research is made for the effects of Raman scattering caused by the soliton excitation occurring in the organic molecular crystals, e.g., acetanilide, on the basis of vibration model of amide-I. The energy gap between the soliton state and the vibron state have been found by partial diagonalized method in second quantized representation, which is 18.1-33 cm -1. This result is approximately consistent with the red shift value obtained from the experiments, 16 cm -1. The differential cross-section of the Raman scattering, arising from the soliton excitation, has also been obtained. Finally, we derive some properties of the Raman scattering in such a case. This result establishes spectral signatures of the soliton in the molecular crystals, which may be observed in the experiment.

  2. The Alaska Mineral Resource Assessment Program; background information to accompany geologic and mineral-resource maps of the Cordova and Middleton Island quadrangles, southern Alaska

    USGS Publications Warehouse

    Winkler, Gary R.; Plafker, George; Goldfarb, R.J.; Case, J.E.

    1992-01-01

    report summarizes recent results of integrated geological, geochemical, and geophysical field and laboratory studies conducted by the U.S. Geological Survey in the Cordova and Middleton Island 1?x3 ? quadrangles of coastal southern Alaska. Published open-file reports and maps accompanied by descriptive and interpretative texts, tables, diagrams, and pertinent references provide background information for a mineral-resource assessment of the two quadrangles. Mines in the Cordova and Middleton Island quadrangles produced copper and byproduct gold and silver in the first three decades of the 20th century. The quadrangles may contain potentially significant undiscovered resources of precious and base metals (gold, silver, copper, zinc, and lead) in veins and massive sulfide deposits hosted by Cretaceous and Paleogene sedimentary and volcanic rocks. Resources of manganese also may be present in the Paleogene rocks; uranium resources may be present in Eocene granitic rocks; and placer gold may be present in beach sands near the mouth of the Copper River, in alluvial sands within the canyons of the Copper River, and in smaller alluvial deposits underlain by rocks of the Valdez Group. Significant coal resources are present in the Bering River area, but difficult access and structural complexities have discouraged development. Investigation of numerous oil and gas seeps near Katalla in the eastern part of the area led to the discovery of a small, shallow field from which oil was produced between 1902 and 1933. The field has been inactive since, and subsequent exploration and drilling onshore near Katalla in the 1960's and offshore near Middleton Island on the outer continental shelf in the 1970's and 1980's was not successful.

  3. Crystal-Chemical Analysis Martian Minerals in Gale Crater

    NASA Technical Reports Server (NTRS)

    Morrison, S. M.; Downs, R. T.; Blake, D. F.; Bish, D. L.; Ming, D. W.; Morris, R. V.; Yen, A. S.; Chipera, S. J.; Treiman, A. H.; Vaniman, D. T.; Gellert, R.; Achilles, C. N..; Rampe, E. B.; Bristow, T. F.; Crisp, J. A.; Sarrazin, P. C.; Farmer, J. D.; DesMarais, D. J.; Grotzinger, J. P.; Stolper, E. M.; Morookian, J. M.; Wilson, M. A.; Spanovich, N.; Anderson, R. C.

    2015-01-01

    The CheMin instrument on the Mars Science Laboratory rover Curiosity performed X-ray diffraction analyses on scooped soil at Rocknest and on drilled rock fines at Yellowknife Bay (John Klein and Cumberland samples), The Kimberley (Windjana sample), and Pahrump (Confidence Hills sample) in Gale crater, Mars. Samples were analyzed with the Rietveld method to determine the unit-cell parameters and abundance of each observed crystalline phase. Unit-cell parameters were used to estimate compositions of the major crystalline phases using crystal-chemical techniques. These phases include olivine, plagioclase and clinopyroxene minerals. Comparison of the CheMin sample unit-cell parameters with those in the literature provides an estimate of the chemical compositions of the major crystalline phases. Preliminary unit-cell parameters, abundances and compositions of crystalline phases found in Rocknest and Yellowknife Bay samples were reported in. Further instrument calibration, development of 2D-to- 1D pattern conversion corrections, and refinement of corrected data allows presentation of improved compositions for the above samples.

  4. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resource maps of the Ajo and Lukeville 1 degree x 2 degrees quadrangles, Arizona

    USGS Publications Warehouse

    Gray, Floyd; Tosdal, R.M.; Peterson, J.A.; Cox, D.P.; Miller, R.J.; Klein, D.P.; Theobald, P.K.; Haxel, G.B.; Grubensky, M.J.; Raines, G.L.; Barton, H.N.; Singer, D.A.; Eppinger, R.G.

    1992-01-01

    Encompassing about 21,000 km 2 in southwestern Arizona, the Ajo and Lukeville 1 ? by 2 ? quadrangles have been the subject of mineral resource investigations utilizing field and laboratory studies in the disciplines of geology, geochemistry, geophysics, and Landsat imagery. The results of these studies are published as a folio of maps, figures, and tables, with accompanying discussions. Past mineral production has been limited to copper from the Ajo Mining District. In addition to copper, the quadrangles contain potentially significant resources of gold and silver; a few other commodities, including molybdenum and evaporites, may also exist in the area as appreciable resources. This circular provides background information on the mineral deposits and on the investigations and integrates the information presented in the folio. The bibliography cites references to the geology, geochemistry, geophysics, and mineral deposits of the two quadrangles.

  5. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Walker Lake 1 degree x 2 degrees Quadrangle, California and Nevada

    USGS Publications Warehouse

    Stewart, John Harris; Chaffee, M.A.; Dohrenwend, J.C.; John, D.A.; Kistler, R.W.; Kleinhampl, F.J.; Menzie, W.D.; Plouff, Donald; Rowan, L.C.; Silberling, Norman J.

    1984-01-01

    The Walker Lake 1? by 2? quadrangle in eastern California and western Nevada was studied by an interdisciplinary research team to appraise its mineral resources. The appraisal is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The selected bibliography lists selected references to the geology, geochemistry, geophysics, and mineral deposits of the Walker Lake 1? by 2? quadrangle.

  6. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Tonopah 1 by 2 degree Quadrangle, Nevada

    USGS Publications Warehouse

    John, David A.; Nash, J.T.; Plouff, Donald; Whitebread, D.H.

    1991-01-01

    The Tonopah 1 ? by 2 ? quadrangle in south-central Nevada was studied by an interdisciplinary research team to appraise its mineral resources. The appraisal is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The selected bibliography lists references to the geology, geochemistry, geophysics, and mineral deposits of the Tonopah 1 ? by 2 ? quadrangle.

  7. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resource maps of the Choteau 1 degree x 2 degrees Quadrangle, Montana

    USGS Publications Warehouse

    Earhart, Robert L.; Grimes, David J.; Leinz, Reinhard W.; Kleinkopf, M. Dean

    1981-01-01

    The Choteau l? x 2? quadrangle in northwest Montana was studied by an interdisciplinary research team in order to appraise its mineral resource and hydrocarbon potential The appraisal is based on field and laboratory investigations of the geology, geochemistry, and geophysics. The results of the investigations are published as a folio of maps, figures, tables, and accompanying discussions. This circular provides background information on the investigations and integrates the published components of the resource appraisal. A comprehensive bibliography cites both specific and general references to the geology, geochemistry, geophysics, and mineral deposits of the Choteau l? x 2? quadrangle.

  8. The Conterminous United States Mineral Assessment Project; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Reno 1 by 2 degree Quadrangle, Nevada and California

    USGS Publications Warehouse

    John, David A.; Stewart, John H.; Hendricks, J.D.; Rowan, L.C.; Plouff, Donald

    1992-01-01

    The Reno 1 ? by 2 ? quadrangle in west-central Nevada was studied by an interdisciplinary research team to appraise its mineral resources. The assessment is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, reports, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The selected bibliography lists references to the geology, geochemistry, geophysics, and mineral deposits of the Reno 1 ? by 2 ? quadrangle.

  9. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Medford 1 degree x 2 degrees Quadrangle, Oregon and California

    USGS Publications Warehouse

    Smith, James G.; Blakely, R.J.; Johnson, M.G.; Page, N.J.; Peterson, J.A.; Singer, D.A.; Whittington, C.L.

    1986-01-01

    The Medford 1 ? by 2 ? quadrangle in southern Oregon and northern California was studied by an interdisciplinary research team to appraise its mineral resources. The appraisal is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The bibliography lists selected references to the geology, geochemistry, geophysics, and mineral deposits of the Medford 1 ? by 2 ? quadrangle.

  10. The Alaskan mineral resource assessment program; background information to accompany folio of geologic and mineral resource maps of the Ambler River Quadrangle, Alaska

    USGS Publications Warehouse

    Mayfield, Charles F.; Tailleur, I.L.; Albert, N.R.; Ellersieck, Inyo; Grybeck, Donald; Hackett, S.W.

    1983-01-01

    The Ambler River quadrangle, consisting of 14,290 km2 (5,520 mi2) in northwest Alaska, was investigated by an interdisciplinary research team for the purpose of assessing the mineral resource potential of the quadrangle. This report provides background information for a folio of maps on the geology, reconnaissance geochemistry, aeromagnetics, Landsat imagery, and mineral resource evaluation of the quadrangle. A summary of the geologic history, radiometric dates, and fossil localities and a comprehensive bibliography are also included. The quadrangle contains jade reserves, now being mined, and potentially significant resources of copper, zinc, lead, and silver.

  11. Mineral crystal alignment in mineralized fracture callus determined by 3D small-angle X-ray scattering

    NASA Astrophysics Data System (ADS)

    Liu, Yifei; Manjubala, Inderchand; Roschger, Paul; Schell, Hanna; Duda, Georg N.; Fratzl, Peter

    2010-10-01

    Callus tissue formed during bone fracture healing is a mixture of different tissue types as revealed by histological analysis. But the structural characteristics of mineral crystals within the healing callus are not well known. Since two-dimensional (2D) scanning small-angle X-ray scattering (sSAXS) patterns showed that the size and orientation of callus crystals vary both spatially and temporally [1] and 2D electron microscopic analysis implies an anisotropic property of the callus morphology, the mineral crystals within the callus are also expected to vary in size and orientation in 3D. Three-dimensional small-angle X-ray scattering (3D SAXS), which combines 2D SAXS patterns collected at different angles of sample tilting, has been previously applied to investigate bone minerals in horse radius [2] and oim/oim mouse femur/tibia [3]. We implement a similar 3D SAXS method but with a different way of data analysis to gather information on the mineral alignment in fracture callus. With the proposed accurate yet fast assessment of 3D SAXS information, it was shown that the plate shaped mineral particles in the healing callus were aligned in groups with their predominant orientations occurring as a fiber texture.

  12. Effect of hydrazine based deproteination protocol on bone mineral crystal structure.

    PubMed

    Karampas, I A; Orkoula, M G; Kontoyannis, C G

    2012-05-01

    In several bone deproteination protocols the chemical agent used for protein cleavage is hydrazine. The effect of hydrazine deproteination method on the crystal size and crystallinity of the bone mineral was studied. Bovine bones were subjected to this protocol and the crystal size and crystallinity of the remaining bone mineral were determined by X-ray Diffraction (XRD), by measuring the width at the half of the maximum intensity of the (002) reflection. It was found that hydrazine deproteination induces noteworthy increase of crystal size and crystallinity. The effect was enhanced by increasing hydrazine temperature from 25 to 55°C. Furthermore, infrared spectroscopy revealed that hydrazine facilitates the removal of carbonate and acid phosphate ions from bone mineral. It is proposed that the mechanism of modification of crystal size and crystallinity lies on the removal of these ions thus, resulting in crystal re-organization.

  13. The Alaskan Mineral Resource Assessment Program; background information to accompany folio of geologic and mineral resource maps of the Circle quadrangle, Alaska

    USGS Publications Warehouse

    Foster, Helen Laura; Menzie, W.D.; Cady, J.W.; Simpson, S.L.; Aleinikoff, J.N.; Wilson, F.H.; Tripp, R.B.

    1987-01-01

    The geology, geochemistry, geophysics, and Landsat imagery of the Circle quadrangle were investigated by an interdisciplinary research team for the purpose of assessing the mineral potential of the area. The quadrangle covers approximately 15,765 km2 in east-central Alaska; most of it is included in the mountainous Yukon-Tanana Upland physiographic division, but the northernmost part is in the low-lying Yukon Flats section. The Circle mining district, in the east-central part of the quadrangle, has been a major producing area of placer gold since its discovery in 1893. For descriptive purposes, the Circle quadrangle is divided into three areas: the northwest Circle quadrangle, the area north of the Tintina fault zone, and the area south of the Tintina fault zone. The Tintina fault zone extends northwesterly through the northern part of the quadrangle. The northwest Circle quadrangle contains mostly folded and faulted, slightly metamorphosed sedimentary rocks that are intruded by Tertiary granitic plutons. In the northern part of the area north of the Tintina fault zone (Little Crazy Mountains and northern east Crazy Mountains), the rocks consist primarily of the gabbro and basalt of the Circle Volcanics and minor associated chert, graywacke, and limestone. Elsewhere in this area (south of the Circle Volcanics and in the western Crazy Mountains), the rocks are mostly slightly metamorphosed Paleozoic sedimentary rocks that have been folded and faulted. Rocks in the largest part of the quadrangle, the area south of the Tintina fault zone, consist largely of pelitic rocks that are regionally metamorphosed to greenschist and amphibolite facies. Felsic plutons, mostly Tertiary in age, occur throughout the area. The metamorphic rocks are separated from sedimentary rocks on the northwest by thrust faulting. The aeromagnetic and gravity data show clear differences between the areas north and south of the Tintina fault zone. The metamorphic terrane to the south has low

  14. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic, geochemical, remote sensing, and mineral resources maps of the Butte 1 degree x 2 degrees Quadrangle, Montana

    USGS Publications Warehouse

    Elliott, James E.; Trautwein, C.M.; Wallace, C.A.; Lee, G.K.; Rowan, L.C.; Hanna, W.F.

    1993-01-01

    The Butte 1?x2 ? quadrangle in west-central Montana was investigated as part of the U.S. Geological Survey's Conterminous United States Mineral Assessment Program (CUSMAP). These investigations included geologic mapping, geochemical surveys, gravity and aeromagnetic surveys, examinations of mineral deposits, and specialized geochronologic and remote-sensing studies. The data collected during these studies were compiled, combined with available published and unpublished data, analyzed, and used in a mineral-resource assessment of the quadrangle. The results, including data, interpretations, and mineral-resource assessments for nine types of mineral deposits, are published separately as a folio of maps. These maps are accompanied by figures, tables, and explanatory text. This circular provides background information on the Butte quadrangle, summarizes the studies and published maps, and lists a selected bibliography of references pertinent to the geology, geochemistry, geophysics, and mineral resources of the quadrangle. The Butte quadrangle, which includes the world-famous Butte mining district, has a long history of mineral production. Many mining districts within the quadrangle have produced large quantities of many commodities; the most important in dollar value of production were copper, gold, silver, lead, zinc, manganese, molybdenum, and phosphate. At present, mines at several locations produce copper, molybdenum, gold, silver, lead, zinc, and phosphate. Exploration, mainly for gold, has indicated the presence of other mineral deposits that may be exploited in the future. The results of the investigations by the U.S. Geological Survey indicate that many areas of the quadrangle are highly favorable for the occurrence of additional undiscovered resources of gold, silver, copper, molybdenum, tungsten, and other metals in several deposit types.

  15. The Alaskan Mineral Resource Assessment Program; background information to accompany folio of geologic and mineral resource maps of the Big Delta Quadrangle, Alaska

    USGS Publications Warehouse

    Foster, Helen Laura; Albert, N.R.D.; Griscom, Andrew; Hessin, T.D.; Menzie, W.D.; Turner, D.L.; Wilson, F.H.

    1979-01-01

    The geology, geochemistry, geophysics, and Landsat imagery of the Big Delta quadrangle, 16,335 km 2 in the Yukon-Tanana Upland of east-central Alaska, were investigated, and maps and reports were prepared by an interdisciplinary research team for the purpose of assessing the mineral potential. The quadrangle is dominantly a complex terrane of greenschist- to amphibolitefacies metamorphic rocks that have been intruded by Mesozoic and Tertiary dioritic to granitic rocks and are overlain by Tertiary sedimentary and volcanic rocks. Serpentinized peridotite and associated greenstone, graywacke, and chert crop out in some places. The quadrangle is bisected by the northeastward-trending Shaw Creek fault, which, on the basis of aeromagnetic interpretation and geologic data, is postulated to have left-lateral offset of as much as 48 km. On the northwest side of the Shaw Creek fault, metamorphic rock units have a northwesterly regional trend, and the oldest rocks could be Precambrian in age. Gneiss and schist in the southwestern part of the quadrangle are derived from both igneous and sedimentary protoliths, some of which may be as old as Precambrian. Other rock units, which include calcareous schist and thin-layered marble, black quartzite, semischist, and cataclastic rocks, are considered to be of probable Paleozoic age, although no fossils have yet been found in these rocks. Radiolarians and conodonts in chert associated with greenstone and ultramafic rocks indicate that the chert is of Permian age. Potassium-argon ages on igneous rocks of the Big Delta quadrangle fall into two groups: those with biotite, muscovite, hornblende, and sanidine ages between 50 to 69 m.y.; and those with biotite, hornblende, and sanidine ages between 88 to 105 m.y. The younger of these two groups appears to indicate the time of a plutonic event marked by intrusion of mostly small, isolated plutons, including hypabyssal stocks, and the eruption of silicic volcanic rocks. Most of the plutons are

  16. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic, geochemical, geophysical, remote sensing, and mineral resource maps of the Wallace 1 degree x 2 degrees Quadrangle, Montana and Idaho

    USGS Publications Warehouse

    Harrison, Jack Edward; Leach, David L.; Kleinkopf, M. Dean; Long, Carl L.; Rowan, Larry C.; Marvin, Richard F.

    1986-01-01

    The Wallace 1? x 2 quadrangle in Montana and Idaho was studied by an interdisciplinary research team that included geologists, geochemists, and geophysicists, as well as specialists in isotopic dating and remote sensing. The basic data resulting from these studies, as well as the final metallic mineral resource assessments, are published as a folio of maps, figures, tables, and accompanying discussions. This circular provides background information on the studies and lists the published components of the resource appraisal. An extensive bibliography lists both specific and general references that apply to this geoscience study of the quadrangle.

  17. The use of mineral crystals as bio-markers in the search for life on Mars

    NASA Technical Reports Server (NTRS)

    Schwartz, D. E.; Mancinelli, R. L.; Kaneshiro, E. S.

    1992-01-01

    It is proposed that minerals resulting from biologically controlled mineralization processes be utilized as biomarkers because of their favorable qualities. Universal signatures of life (biomarkers) are discussed in terms of their terrestrial forms and hypothetical Martian counterparts including organics, suites of specific inorganic and organic compounds, and isotopic ratios. It is emphasized that minerals produced under biologic control have morphological and isotopic compositions that are not found in their abiotic counterparts. Other biomarkers are not necessarily indicative of biological origin and are therefore unreliable resources for scientific study. Mineral crystals are also stable over long geological periods, and the minerals from Martian fluvial features can therefore be employed to search for fossils and biomarkers of early biological activity.

  18. Minerals

    MedlinePlus

    Minerals are important for your body to stay healthy. Your body uses minerals for many different jobs, including keeping your bones, muscles, heart, and brain working properly. Minerals are also important for making enzymes and hormones. ...

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

    PubMed

    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 < 4, 0.445 mass % of PO4(3-), inorganic impurities presence), dissolved substrates (magnesium and ammonium chlorides) and solution alkalising the environment of struvite MgNH4PO4·6H2O reaction crystallization process. Research ran in constant temperature 298 K assuming stoichiometric proportions of substrates or 20% excess of magnesium ions. Influence of pH (8.5-10) and mean residence time (900-3600 s) on product size distribution, its chemical composition, crystals shape, size-homogeneity and process kinetics was identified. Crystals of mean size ca. 25-37 μm and homogeneity CV 70-83% were produced. The largest crystals, of acceptable homogeneity, were produced using 20% excess of magnesium ions, pH 9 and mean residence time 3600 s. Under these conditions nucleation rate did not exceed 9 × 10(7) 1/(s m(3)) according to SIG (Size Independent Growth) MSMPR kinetic model. Linear crystal growth rate was 4.27 × 10(-9) m/s. Excess of magnesium ions influenced struvite reaction crystallization process yield advantageously. Concentration of 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.

  20. Evaluating Young Volcanism at Baitoushan Volcano: Insights From Single Mineral Crystal Sr and Pb Isotope Analyses

    NASA Astrophysics Data System (ADS)

    Rodgers, S. L.; Ramos, F. C.; Gill, J. B.

    2008-12-01

    Baitoushan volcano, located along the North-Korea/China border, generated one of the largest caldera- forming rhyolitic eruptions in the northern hemisphere in the last 2000 years. In addition to a large ~1000AD comendite eruption, a pantellerite eruption occurred at ~0AD which left a small pumice deposit. We have evaluated the isotopic signatures of single mineral crystals and pumice fragments from this pantellerite to evaluate the sources, petrogenetic history, timing, and residence of highly alkaline rhyolitic magma at Baitoushan. Single mineral isotope characteristics of this pantellerite are complex. Rb/Sr analyses of whole pumice fragments suggest a pantellerite residence age of ~348ky, similar to residence ages determined for Long Valley Caldera and Valles Caldera. Individual potassium feldspar and clinopyroxene crystals have similarly variable and overlapping 87Sr/86Sr signatures that are different than those of host pumice fragments but similar to crystals erupted in the ~1000AD comendite. These same crystals define a linear trend in 207Pb/204Pb vs 206Pb/204Pb that suggests mixing between host pumice and a second currently unidentified endmember. Results, however, unequivocally demonstrate mixing and undermine any residence age associated with Rb/Sr isotope systematics of pumice fragments. Overall Sr and Pb isotope systematics reflect variable signatures as compared to all other recent eruptive products at Baitoushan and suggest highly variable processes involved in melt production and that select minerals may be shared between different eruptions spanning a 2000 to 4000 year time period.

  1. Crystal chemistry of hydroxyl and water in silicate minerals. Final technical report

    SciTech Connect

    Smyth, J.R.

    1998-06-01

    This was a project to investigate the crystal chemistry of OH and H{sub 2}O substitution in silicate minerals by use of X-ray and neutron diffraction methods combined with IR spectroscopy and to interpret and generalize the results using an electrostatic model for these mineral structures. Using these data together with published H position data electrostatic parameters for H sites were calculated from a simple electrostatic model. The data were then used to refine the model for incorporation of H into the wadsleyite structure. This has led to recent work on the synthesis and characterization of hydrous wadsleyites.

  2. Mineral chemistry of the Tissint meteorite: Indications of two-stage crystallization in a closed system

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Baziotis, Ioannis P.; Asimow, Paul D.; Bodnar, Robert J.; Taylor, Lawrence A.

    2016-12-01

    The Tissint meteorite is a geochemically depleted, olivine-phyric shergottite. Olivine megacrysts contain 300-600 μm cores with uniform Mg# ( 80 ± 1) followed by concentric zones of Fe-enrichment toward the rims. We applied a number of tests to distinguish the relationship of these megacrysts to the host rock. Major and trace element compositions of the Mg-rich core in olivine are in equilibrium with the bulk rock, within uncertainty, and rare earth element abundances of melt inclusions in Mg-rich olivines reported in the literature are similar to those of the bulk rock. Moreover, the P Kα intensity maps of two large olivine grains show no resorption between the uniform core and the rim. Taken together, these lines of evidence suggest the olivine megacrysts are phenocrysts. Among depleted olivine-phyric shergottites, Tissint is the first one that acts mostly as a closed system with olivine megacrysts being the phenocrysts. The texture and mineral chemistry of Tissint indicate a crystallization sequence of: olivine (Mg# 80 ± 1) → olivine (Mg# 76) + chromite → olivine (Mg# 74) + Ti-chromite → olivine (Mg# 74-63) + pyroxene (Mg# 76-65) + Cr-ulvöspinel → olivine (Mg# 63-35) + pyroxene (Mg# 65-60) + plagioclase, followed by late-stage ilmenite and phosphate. The crystallization of the Tissint meteorite likely occurred in two stages: uniform olivine cores likely crystallized under equilibrium conditions; and a fractional crystallization sequence that formed the rest of the rock. The two-stage crystallization without crystal settling is simulated using MELTS and the Tissint bulk composition, and can broadly reproduce the crystallization sequence and mineral chemistry measured in the Tissint samples. The transition between equilibrium and fractional crystallization is associated with a dramatic increase in cooling rate and might have been driven by an acceleration in the ascent rate or by encounter with a steep thermal gradient in the Martian crust.

  3. Electron and positive ion emission accompanying fracture of Wint-o-Green Lifesavers and single-crystal sucrose

    SciTech Connect

    Dickinson, J.T.; Brix, L.B.; Jensen, L.C.

    1984-04-26

    It is a well-known fact that, when Wint-o-Green Lifesavers (Lifesaver is a registered trademark of Lifesaver, Inc.) are broken in air, one observes intense triboluminescence. Measurements of the emission of electrons and positive ions from the fracture of these Lifesavers under vacuum, as well as from single-crystal sucrose are reported herein. The emission of photons and radio waves during fracture under vacuum is also presented for sucrose, indicating the occurrence of a gaseous discharge in the crack tip during crack growth. Comparisons of the various emission curves are presented and discussed in terms of stress-induced charge separation.

  4. Morphological Analysis of White Cement Clinker Minerals: Discussion on the Crystallization-Related Defects

    PubMed Central

    Benmohamed, Mohamed; Alouani, Rabah; Jmayai, Amel; Ben Haj Amara, Abdesslem; Ben Rhaiem, Hafsia

    2016-01-01

    The paper deals with a formation of artificial rock (clinker). Temperature plays the capital role in the manufacturing process. So, it is useful to analyze a poor clinker to identify the different phases and defects associated with their crystallization. X-ray fluorescence spectroscopy was used to determine the clinker's chemical composition. The amounts of the mineralogical phases are measured by quantitative XRD analysis (Rietveld). Scanning electron microscopy (SEM) was used to characterize the main phases of white Portland cement clinker and the defects associated with the formation of clinker mineral elements. The results of a study which focused on the identification of white clinker minerals and defects detected in these noncomplying clinkers such as fluctuation of the amount of the main phases (alite (C3S) and belite (C2S)), excess of the free lime, occurrence of C3S polymorphs, and occurrence of moderately-crystallized structures are presented in this paper. PMID:27313617

  5. From crystal to glass-like thermal conductivity in crystalline minerals.

    PubMed

    Bouyrie, Y; Candolfi, C; Pailhès, S; Koza, M M; Malaman, B; Dauscher, A; Tobola, J; Boisron, O; Saviot, L; Lenoir, B

    2015-08-14

    The ability of some materials with a perfectly ordered crystal structure to mimic the heat conduction of amorphous solids is a remarkable physical property that finds applications in numerous areas of materials science, for example, in the search for more efficient thermoelectric materials that enable to directly convert heat into electricity. Here, we unveil the mechanism in which glass-like thermal conductivity emerges in tetrahedrites, a family of natural minerals extensively studied in geology and, more recently, in thermoelectricity. By investigating the lattice dynamics of two tetrahedrites of very close compositions (Cu12Sb2Te2S13 and Cu10Te4S13) but with opposite glasslike and crystal thermal transport by means of powder and single-crystal inelastic neutron scattering, we demonstrate that the former originates from the peculiar chemical environment of the copper atoms giving rise to a strongly anharmonic excess of vibrational states.

  6. Dynamics of mineral crystallization from precipitated slab-derived fluid phase: first in situ synchrotron X-ray measurements

    NASA Astrophysics Data System (ADS)

    Malaspina, Nadia; Alvaro, Matteo; Campione, Marcello; Wilhelm, Heribert; Nestola, Fabrizio

    2015-03-01

    Remnants of the fluid phase at ultrahigh pressure (UHP) in subduction environments may be preserved as primary multiphase inclusions in UHP minerals. The mode of crystallization of daughter minerals during precipitation within the inclusion and/or the mechanism of interaction between the fluid at supercritical conditions and the host mineral are still poorly understood from a crystallographic point of view. A case study is represented by garnet-orthopyroxenites from the Maowu Ultramafic Complex (China) deriving from harzburgite precursors metasomatized at ~4 GPa, 750 °C by a silica- and incompatible trace element-rich fluid phase. This metasomatism produced poikilitic orthopyroxene and inclusion-rich garnet porphyroblasts. Solid multiphase primary inclusions in garnet display a size within a few tens of micrometres and negative crystal shapes. Infilling minerals (spinel: 10-20 vol%; amphibole, chlorite, talc, mica: 80-90 vol%) occur with constant volume proportions and derive from trapped solute-rich aqueous fluids. To constrain the possible mode of precipitation of daughter minerals, we performed for the first time a single-crystal X-ray diffraction experiment by synchrotron radiation at Diamond Light Source. In combination with electron probe microanalyses, this measurement allowed the unique identification of each mineral phase and reciprocal orientations. We demonstrated the epitaxial relationship between spinel and garnet and between some hydrous minerals. Such information is discussed in relation to the physico-chemical aspects of nucleation and growth, shedding light on the mode of mineral crystallization from a fluid phase trapped at supercritical conditions.

  7. Biomimetic calcium phosphate crystal mineralization on electrospun cellulose-based scaffolds.

    PubMed

    Rodríguez, Katia; Renneckar, Scott; Gatenholm, Paul

    2011-03-01

    Novel cellulose based-scaffolds were studied for their ability to nucleate bioactive calcium phosphate crystals for future bone healing applications. Cellulose-based scaffolds were produced by electrospinning cellulose acetate (CA) dissolved in a mixture of acetone/dimethylacetamide (DMAc). The resulting nonwoven CA mats containing fibrils with diameters in the range of 200 nm to 1.5 μm were saponified by NaOH/ethanol for varying times to produce regenerated cellulose scaffolds. Biomimetic crystal growth nucleated from the fiber surface was studied as a function of surface chemistry. Regenerated cellulose scaffolds of varying treatments were soaked in simulated body fluid (SBF) solution. Scaffolds that were treated with CaCl(2), a mixture of carboxymethyl cellulose (CMC) and CaCl(2), and NaOH and CaCl(2), were analyzed using X-ray photoelectron spectroscopy, X-ray powder diffraction, and scanning electron microscopy to understand the growth of bioactive calcium phosphate (Ca-P) crystals as a function of surface treatment. The crystal structure of the nucleated Ca-P crystals had a diffraction pattern similar to that of hydroxyapatite, the mineralized component of bone. The study shows that the scaffold surface chemistry can be manipulated, providing numerous routes to engineer cellulosic substrates for the requirements of scaffolding.

  8. Crystallization of urine mineral components may depend on the chemical nature of Proteus endotoxin polysaccharides.

    PubMed

    Torzewska, Agnieszka; Staczek, Paweł; Rózalski, Antoni

    2003-06-01

    Formation of infectious urinary calculi is the most common complication accompanying urinary tract infections by members of the genus Proteus. The major factor involved in stone formation is the urease produced by these bacteria, which causes local supersaturation and crystallization of magnesium and calcium phosphates as carbonate apatite [Ca(10)(PO(4))(6).CO(3)] and struvite (MgNH(4)PO(4).6H(2)O), respectively. This effect may also be enhanced by bacterial polysaccharides. Macromolecules of such kind contain negatively charged residues that are able to bind Ca(2+) and Mg(2+), leading to the accumulation of these ions around bacterial cells and acceleration of the crystallization process. The levels of Ca(2+) and Mg(2+) ions bound by whole Proteus cells were measured, as well as the chemical nature of isolated LPS polysaccharides, and the intensity of the in vitro crystallization process was compared in a synthetic urine. The results suggest that the sugar composition of Proteus LPS may either enhance or inhibit the crystallization of struvite and apatite, depending on its chemical structure and ability to bind cations. This points to the increased importance of endotoxin in urinary tract infections.

  9. The Alaska Mineral Resource Assessment Program; background information to accompany folio of geologic and resource maps of the Ugashik, Bristol Bay, and western part of Karluk quadrangles, Alaska

    USGS Publications Warehouse

    Detterman, Robert L.; Case, J.E.; Church, S.E.; Frisken, J.G.; Wilson, F.H.; Yount, M.E.

    1990-01-01

    The Ugashik, Bristol Bay, and western part of Karluk quadrangles (1:250,000) are a part of the Alaska Peninsula in southwestern Alaska. This circular, in conjunction with a companion folio of MF-series maps, two I-series geologic maps, and three bulletins, represents the results of integrated field and laboratory studies on the geology, geophysics, geochemistry, paleontology, geochronology, and mineral resources of the quadrangles. These studies were undertaken to provide a modern assessment of the mineral and energy resources of the quadrangles. Each map contains descriptive text, explanatory material, tables, diagrams, and pertinent references. This circular provides background information for the mineral resource assessment map (MF-1539-1) and integrates the component M F- and I-series maps. A comprehensive bibliography cites both specific and general references relevant to the geology and resources of the quadrangles.

  10. Crystal structure of ilyukhinite, a new mineral of the eudialyte group

    NASA Astrophysics Data System (ADS)

    Rastsvetaeva, R. K.; Rozenberg, K. A.; Chukanov, N. V.; Aksenov, S. M.

    2017-01-01

    The crystal structure of ilyukhinite, a new mineral of the eudialyte group, is studied by X-ray diffraction. The mineral found in pegmatite bodies of the Kukisvumchorr Mountain (Khibiny alkaline complex) is characterized by low sodium content, high degree of hydration, and predominance of manganese over iron. The trigonal cell has the following parameters: a = 14.1695(6) and c = 31.026(1) Å; space group R3m. The structure is refined to final R = 0.046 in the anisotropic approximation of atomic displacements using 1527 F > 3σ F. The idealized formula of ilyukhinite ( Z = 3) is written as (H3O,Na)14Ca6Mn2Zr3Si26O72(OH)2 · 3H2O. The new mineral differs from other representatives of the eudialyte group by the predominance of both oxonium in the N positions of extra-framework cations and manganese in the M2 position centering the tetragonal pyramid.

  11. ContaMiner and ContaBase: a webserver and database for early identification of unwantedly crystallized protein contaminants

    PubMed Central

    Hungler, Arnaud; Momin, Afaque; Diederichs, Kay; Arold, Stefan, T.

    2016-01-01

    Solving the phase problem in protein X-ray crystallography relies heavily on the identity of the crystallized protein, especially when molecular replacement (MR) methods are used. Yet, it is not uncommon that a contaminant crystallizes instead of the protein of interest. Such contaminants may be proteins from the expression host organism, protein fusion tags or proteins added during the purification steps. Many contaminants co-purify easily, crystallize and give good diffraction data. Identification of contaminant crystals may take time, since the presence of the contaminant is unexpected and its identity unknown. A webserver (ContaMiner) and a contaminant database (ContaBase) have been established, to allow fast MR-based screening of crystallographic data against currently 62 known contaminants. The web-based ContaMiner (available at http://strube.cbrc.kaust.edu.sa/contaminer/) currently produces results in 5 min to 4 h. The program is also available in a github repository and can be installed locally. ContaMiner enables screening of novel crystals at synchrotron beamlines, and it would be valuable as a routine safety check for ‘crystallization and preliminary X-ray analysis’ publications. Thus, in addition to potentially saving X-ray crystallographers much time and effort, ContaMiner might considerably lower the risk of publishing erroneous data. PMID:27980519

  12. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic and mineral resource maps of the Silver City 1 degree x 2 degrees Quadrangle, New Mexico and Arizona

    USGS Publications Warehouse

    Richter, Donald H.; Houser, B.B.; Watts, K.C.; Klein, D.P.; Sharp, W.N.; Drewes, Harald; Hedlund, D.C.; Raines, G.L.; Hassemer, J.R.

    1987-01-01

    The Silver City 1 ? x 2 ? quadrangle, consisting of about 20,650 km2 in southwestern New Mexico and southeastern Arizona, has been investigated by a multidisciplinary research team for the purpose of assessing its mineral resource potential. The results of this investigation are in a folio of 21 maps that contain detailed information on the geology, geochemistry, geophysics, mineral deposits, and potential mineral resources of the quadrangle. This Circular provides background information on the various studies and integrates the component maps. It contains an extensive selected bibliography pertinent to the geology and mineral deposits of the quadrangle. The quadrangle has produced more than $3.5 billion in mineral products since about 1850 and contains significant resources of gold, silver, copper, molybdenum, lead, zinc, iron, manganese-iron, zeolite minerals, and possibly tin and tungsten.

  13. Rare earth elements in minerals of the ALHA77005 shergottite and implications for its parent magma and crystallization history

    NASA Technical Reports Server (NTRS)

    Lundberg, Laura L.; Crozaz, Ghislaine; Mcsween, Harry Y., Jr.

    1990-01-01

    Analyses of mineral REE and selected minor and trace elements were carried out on individual grains of pyroxenes, whitlockite, maskelynite, and olivine of the Antarctic shergottite ALHA77005, and the results are used to interpret its parent magma and crystallization history. The results of mineral compositions and textural observations suggest that ALHA77005 is a cumulate with about half cumulus material (olivine + chromite) and half postcumulus phases. Most of the REEs in ALHA77005 reside in whitlockite whose modal concentration is about 1 percent. Mineral REE data support previous suggestions that plagioclase and whitlockite crystallized late, and that low-Ca pyroxene initiated crystallization before high-Ca pyroxene. The REE patterns for the intercumulus liquid, calculated from distribution coefficients for ALHA77005 pyroxene, plagioclase, and whitlockite, are in very good agreement and are similar to that of Shergotty.

  14. Incorporation of Np(V) and U(VI) in Carbonate and Sulfate Minerals Crystallized from Aqueous Solution

    SciTech Connect

    Balboni, Enrica; Morrison, Jessica M.; Wang, Zheming; Engelhard, Mark H.; Burns, Peter C.

    2015-02-15

    The neptunyl Np(V)O2 + and uranyl U(VI)O2 2+ ions are soluble in groundwater, although their interaction with minerals in the subsurface may impact their mobility. One mechanism for the immobilization of actinyl ions in the subsurface is coprecipitation in low-temperature minerals that form naturally, or that are induced to form as part of a remediation strategy. Important differences in the crystal-chemical behavior of the Np(V) neptunyl and U(VI) uranyl ions suggest their behavior towards incorporation into growing crystals may differ significantly. Using a selection of low temperature minerals synthesized in aqueous systems under ambient conditions, this study examines the factors that impact the structural incorporation of the Np(V) neptunyl and U(VI) uranyl ions in carbonate and sulfate minerals.

  15. Nonclassical crystallization in vivo et in vitro (II): Nanogranular features in biomimetic minerals disclose a general colloid-mediated crystal growth mechanism.

    PubMed

    Rodríguez-Navarro, Carlos; Ruiz-Agudo, Encarnación; Harris, Joe; Wolf, Stephan E

    2016-11-01

    Recent research has shown that biominerals and their biomimetics (i) typically form via an amorphous precursor phase, and (ii) commonly display a nanogranular texture. Apparently, these two key features are closely related, underlining the fact that the formation of biominerals and their biomimetics does not necessarily follow classical crystallization routes, and leaves a characteristic nanotextural imprint which may help to disclose their origins and formation mechanisms. Here we present a general overview of the current theories and models of nonclassical crystallization and their applicability for the advance of our current understanding of biomineralization and biomimetic mineralization. We pay particular attention to the link between nonclassical crystallization routes and the resulting nanogranular textures of biomimetic CaCO3 mineral structures. After a general introductory section, we present an overview of classical nucleation and crystal growth theories and their limitations. Then, we introduce the Ostwald's step rule as a general framework to explain nonclassical crystallization. Subsequently, we describe nonclassical crystallization routes involving stable prenucleation clusters, dense liquid and solid amorphous precursor phases, as well as current nonclassical crystal growth models. The latter include oriented attachment, mesocrystallization and the new model based on the colloidal growth of crystals via attachment of amorphous nanoparticles. Biomimetic examples of nanostructured CaCO3 minerals formed via these nonclassical routes are presented which help us to show that colloid-mediated crystal growth can be regarded as a wide-spread growth mechanism. Implications of these observations for the advance in the current understanding on the formation of biomimetic materials and biominerals are finally outlined.

  16. Isotopic Zonation Within Sulfate Evaporite Mineral Crystals Reveal Quantitative Paleoenvironment Details

    NASA Astrophysics Data System (ADS)

    Coleman, M.; Rhorssen, M.; Mielke, R. E.

    2008-12-01

    Isotopic variations measured within a single crystal of hydrated magnesium sulfate are greater than 30 permil for delta 2-H, almost 10 permil for δ18O in water of hydration; and greater than 3 permil in sulfate oxygen. These results are interpreted to indicate the relative humidity of the system during evaporation (15 to 20 percent in this test case) and constrain the volume of water involved. The theoretical basis of this system is the isotopic fractionation between the species in solution and those precipitated as evaporite salts. Precipitation preferentially accumulates more of the heavy isotopes of sulfur and oxygen in mineral sulfate, relative to sulfate in solution. During the course of mineral growth this leads to successive depletion of the respective heavier isotopes in the residual brine reflected in a parallel trend in successive precipitates or even in successive zones within a single crystal. The change in isotopic composition at any one time during the process, relative to the initial value, can be described by an isotopic version of the Rayleigh Fractionation equation, depending only on the extent of the completion of the process and the relevant fractionation factor. Evaporation preferentially removes isotopically lighter hydrogen and oxygen leading to successive extents of enrichment in the respective heavier isotopes in the residual water. However, the relative effects on hydrogen and oxygen isotopes differs as function of relative humidity [1]. ALL OF THESE CHANGES ARE PRESERVED IN THE MINERAL ISOTOPE COMPOSITIONS. We precipitated barium sulfate from epsomite or gypsum samples, which was reduced at 1450°C in the presence of graphite and glassy carbon in a Finnigan TC/EA to produce CO for O isotopic analysis in a Finnigan 253 mass spectrometer, while a separate subsample was oxidized to SO2 in a Costech Elemental Analyzer. However, to make progress with this approach we needed to make a large number of measurements of hydration water and so we

  17. Crystal chemical characteristics and physical properties of ferrous minerals as the basis for the formation of functional materials

    NASA Astrophysics Data System (ADS)

    Shmakova, A.; Kanev, B.; Gömze, A. L.; Kotova, O.

    2017-02-01

    Crystal chemical characteristics and physical properties of ferrous minerals can be criteria for search and evaluation of mineral (natural) raw for the production of functional materials. Special attention will be given to new experimental methods of transformation of minerals at different methods of influence. As a probe to identify the relationship between the actual crystalline structure of the mineral and its technological properties we used the oxidation - reduction reactions of iron ore-forming minerals. We will show that the inexpensive and affordable methods of influence at ore and technological products result in the observed Fe2+— Fe3+ charge transfer, which result in the increase of the conversion degree of the structure and change of magnetic properties of the substance.

  18. Crystallization of belite–melilite clinker minerals in the presence of liquid phase

    SciTech Connect

    Kurokawa, Daisuke; Yoshida, Hideto; Fukuda, Koichiro

    2014-06-01

    Crystallization of belite–melilite clinker minerals was studied from the view point of a high temperature equilibrium. Ca{sub 2}SiO{sub 4}–Ca{sub 2}Al{sub 2}SiO{sub 7} and Ca{sub 2}SiO{sub 4}–Ca{sub 2}AlFeSiO{sub 7} clinkers were synthesized at 1330 °C–1650 °C. The constituent phases were determined by X-ray powder diffractometry and optical microscopy. Chemical compositions of the individual clinker minerals were determined using an electron probe microanalyzer. We established the two types of P{sub 2}O{sub 5}-bearing pseudobinary phase diagrams in the systems Ca{sub 2}SiO{sub 4}–Ca{sub 2}Al{sub 2}SiO{sub 7} at 1505 °C–1650 °C and Ca{sub 2}SiO{sub 4}–Ca{sub 2}(Al,Fe){sub 2}SiO{sub 7} at 1330 °C–1550 °C. In the latter system, the liquid phase appeared at 1390 °C, which is approximately 150 °C lower than the temperature of liquid formation in the former system. The melilite phenocrysts larger than 50 μm were observed not only in the slowly cooled Ca{sub 2}SiO{sub 4}–Ca{sub 2}(Al,Fe){sub 2}SiO{sub 7} clinker but also in commercial belite–melilite clinkers. These crystals would be nucleated and grown from a liquid phase which was formed at relatively low temperatures.

  19. Mineral inclusions in garnet crystals and their application in studies of high and ultrahigh pressure rocks

    NASA Astrophysics Data System (ADS)

    Perchuk, Alexei

    2010-05-01

    Mineral inclusions in crystals like garnet, zircon or clinopyroxene play a key role in identifying ultrahigh-pressure (UHP) metamorphic rocks and in deciphering their metamorphic (P) - temperature (T) history. In this contribution, we address the questions related to the modification of garnet interiors mediated by H2O and/or CO2 fluids released either from the mineral inclusions or from the exterior source. The data presented are based on experimental studies of eclogitic garnets containing various mineral inclusions and on petrologic studies of natural rocks from several HP and UHP complexes. An experimental study on eclogitic garnets with different min¬eral inclusions (including hydrous phases and carbonates) from several subduction-related complexes reveals considerable modification of garnet interiors at temperatures of 700-1100˚C and a pressure of 3-4 GPa, representative of different diamond-bearing metamorphic UHP terranes. Epidote, amphibole, and chlorite inclusions in the garnets underwent dehydration melting over the entire experimental PT range. In the presence of aqueous fluids, carbonate minerals in the inclusions began to melt at 800 °C and 3 GPa. Melting gave rise to new garnet, with the composition controlled by the chemistry of the primary inclusions and by PT run conditions. Garnet either grew directly from the melt or formed by metasomatic replacement of host garnet walls, leaving residual melt at the substitution front in the latter case. Partial melting of inclusions decreased the mechanical strength of the garnet host and led to local shearing. The following diagnostic criteria for melt in metamorphic garnet may be formulated on the basis of the experimental study: (1) (sub-) euhedral garnet grows within the inclusion and/or xenomorphic garnet replaces the garnet host; (2) newly formed garnet is characterized by a composition different from the garnet host; (3) the inclusion surface is features characteristic wedge-shaped ledges or radial

  20. Orientation and optical properties of methylene blue crystal for better understanding of interactions with clay mineral surface

    NASA Astrophysics Data System (ADS)

    Milošević, Maja; Logar, Mihovil

    2013-04-01

    The properties of cationic dye Methylene blue (MB) adsorbed on diferent surfaces have been investigated intensively over the years and various models for the orientation of its cations have been proposed (Hang and Brindley, 1970; Bujdak et al., 2003; Li and Zare, 2004; Marr III et al., 1973; Bujdak, 2006).The main objective of this work is to investigate and determine orientation and optical properties of metylene blue crystal upon its crystallization on a glass slate and to use those findings in better understanding of interactions with clay minerals. Cationic dyes have very high affinity for clay surfaces and those interactions are easily detected, therefore these dyes are used to determine several properties of clay surfaces (morphology, layer charge, CEC). For this study, we have selected a group of MB crystal and carried out XRD analysis, polarized absorption spectra measurement (400 - 900 nm) and determination of optical properties (pleochroism, determination of twining and extinction angle) using polarizing microscope. Methylene blue crystals are exhibiting mostly needle like habitus with huge difference in width - length ratio. According to X-ray diffraction it is quite obvious that the y (b) axis is perpendicular to the crystal surface. The x (a) and z (c) axis lie in the crystal plane (010). Crystals exhibit prominent dichroism: from blue (E || elong.) to colorless. In accordance with current interpretation of MB spectra peaks at 647 and 570 nm can be assigned as dimer aggregation and peaks at 475 and 406 nm as higher level of aggregation. All of them exhibit pronounced polarization dependence. The group of peaks at lower energy (700 to 900 nm) do not show significant polarization dependence and they correspond to the J - aggregates. Peak at around 800 nm have been noticed as fluorescence active. In dependence with thickness of the crystals and vibration direction we have observed presence of polysynthetic twinning which can be compared with polysynthetic

  1. Various intensity of Proteus mirabilis-induced crystallization resulting from the changes in the mineral composition of urine.

    PubMed

    Torzewska, Agnieszka; Różalski, Antoni

    2015-01-01

    Infectious urolithiasis is a result of recurrent and chronic urinary tract infections caused by urease-positive bacteria, especially Proteus mirabilis. The main role in the development of this kind of stones is played by bacterial factors such as urease and extracellular polysaccharides, but urinary tract environment also contributes to this process. We used an in vitro model to establish how the changes in the basic minerals concentrations affect the intensity of crystallization which occurs in urine. In each experiment crystallization was induced by an addition of P. mirabilis to artificial urine with a precisely defined chemical composition. Crystallization intensity was determined using the spectrophotometric microdilution method and the chemical composition of formed crystals was established by atomic absorption spectroscopy and colorimetric methods. Increasing the concentration of all crystals forming ions such as Mg(2+), Ca(2+) and phosphate strongly intensified the process of crystallization, whereas reducing the amount of these components below the proper physiological concentration did not affect its intensity. The inhibitory influence of citrate on calcium and magnesium phosphate crystallization and competitive actions of calcium and oxalate ions on struvite crystals formation were not confirmed. In the case of infectious stones the chemical composition of urine plays an important role, which creates a necessity to support the treatment by developing a model of proper diet.

  2. Mineral-resource assessments in Alaska; background information to accompany maps and reports about the geology and undiscovered-mineral-resource potential of the Mount Katmai Quadrangle and adjacent parts of the Naknek and Afognak quadrangles, Alaska Peninsula

    USGS Publications Warehouse

    Riehle, J.R.; Church, S.E.; Detterman, R.L.; Miller, J.W.

    1994-01-01

    Geologic and geochemical field studies were carded out from 1983 to 1987 in the Mount Katmai l?x2 ? quadrangle and adjoining region, at the northeast end of the Alaska Peninsula. The region is nearly entirely within Katmai National Park and Preserve and has had almost no mineral production, so prior to this study there were few data by which to assess the mineral potential of the region. This report describes the folio of publications that have resulted from the study: geologic maps, geochemical results, fossil identifications, radiometric rock ages, and an assessment of the undiscovered-mineral-resource potential of the region. The Katmai region is inferred to potentially have three types of undiscovered mineral deposits: porphyry copper (molybdenum), precious-metal vein, and hot-springs gold. These deposit types occur elsewhere on the Alaska Peninsula in similar geologic units. Evidence suggesting their occurrence in the Katmai region is the presence of trace amounts of metals typically associated with these kinds of deposits in bedrock of certain tracts and in sediments of streams draining those tracts. Magma to provide heat, fractures to provide pathways for mineralizing fluids, and altered rock are required by genetic models of these deposit types. Such features do occur in the Katmai tracts. Confirmation of any mineral deposit in the Katmai region requires detailed follow-up sampling and acquisition of subsurface information, which is beyond the scope of this study. However, producing porphyry deposits are unknown elsewhere on the Alaska Peninsula in similar rocks, so if any such deposits occur in the Katmai region, they are likely to be few in number. Conversely, vein deposits are typically small in size so there may be several of such deposits. The properties and thermal history of the sedimentary rocks that could serve as reservoirs for oil or gas are unfavorable in adjacent regions. Thus the potential of the Katmai region for producible quantities of

  3. Refinement of collagen-mineral interaction: a possible role for osteocalcin in apatite crystal nucleation, growth and development.

    PubMed

    Chen, Ling; Jacquet, Robin; Lowder, Elizabeth; Landis, William J

    2015-02-01

    Mineralization of vertebrate tissues such as bone, dentin, cementum, and calcifying tendon involves type I collagen, which has been proposed as a template for calcium and phosphate ion binding and subsequent nucleation of apatite crystals. Type I collagen thereby has been suggested to be responsible for the deposition of apatite mineral without the need for non-collagenous proteins or other extracellular matrix molecules. Based on studies in vitro, non-collagenous proteins, including osteocalcin and bone sialoprotein, are thought to mediate vertebrate mineralization associated with type I collagen. These proteins, as possibly related to mineral deposition, have not been definitively localized in vivo. The present study has reexamined their localization in the leg tendons of avian turkeys, a representative model of vertebrate mineralization. Immunocytochemistry of osteocalcin demonstrates its presence at the surface of, outside and within type I collagen while that of bone sialoprotein appears to be localized at the surface of or outside type I collagen. The association between osteocalcin and type I collagen structure is revealed optimally when calcium ions are added to the antibody solution in the methodology. In this manner, osteocalcin is found specifically located along the a4-1, b1, c2 and d bands defining in part the hole and overlap zones within type I collagen. From these data, while type I collagen itself may be considered a stereochemical guide for intrafibrillar mineral nucleation and subsequent deposition, osteocalcin bound to type I collagen may also possibly mediate nucleation, growth and development of platelet-shaped apatite crystals. Bone sialoprotein and osteocalcin as well, each immunolocalized at the surface of or outside type I collagen, may affect mineral deposition in these portions of the avian tendon.

  4. Crystallization of the CaCO3 mineral in the presence of the protein ovalbumin

    NASA Astrophysics Data System (ADS)

    Schwahn, Dietmar; Balz, Mathias; Tremel, Wolfgang

    2004-07-01

    The kinetics of CaCO3 mineralization was studied by SANS in a 0.1M aqueous CaCl2 solution in the presence of the protein ovalbumin found in chicken eggs. As the scattering from the protein and the mineral was observed within different Q regimes the evolution of the protein and mineral could be followed independently. It is observed that ovalbumin denaturates during the first 3h and leads to a strong enhancement of mineralization.

  5. Mathematical model to analyze the dissolution behavior of metastable crystals or amorphous drug accompanied with a solid-liquid interface reaction.

    PubMed

    Hirai, Daiki; Iwao, Yasunori; Kimura, Shin-Ichiro; Noguchi, Shuji; Itai, Shigeru

    2017-02-21

    Metastable crystals and the amorphous state of poorly water-soluble drugs in solid dispersions (SDs), are subject to a solid-liquid interface reaction upon exposure to a solvent. The dissolution behavior during the solid-liquid interface reaction often shows that the concentration of drugs is supersaturated, with a high initial drug concentration compared with the solubility of stable crystals but finally approaching the latter solubility with time. However, a method for measuring the precipitation rate of stable crystals and/or the potential solubility of metastable crystals or amorphous drugs has not been established. In this study, a novel mathematical model that can represent the dissolution behavior of the solid-liquid interface reaction for metastable crystals or amorphous drug was developed and its validity was evaluated. The theory for this model was based on the Noyes-Whitney equation and assumes that the precipitation of stable crystals at the solid-liquid interface occurs through a first-order reaction. Moreover, two models were developed, one assuming that the surface area of the drug remains constant because of the presence of excess drug in the bulk and the other that the surface area changes in time-dependency because of agglomeration of the drug. SDs of Ibuprofen (IB)/polyvinylpyrrolidone (PVP) were prepared and their dissolution behaviors under non-sink conditions were fitted by the models to evaluate improvements in solubility. The model assuming time-dependent surface area showed good agreement with experimental values. Furthermore, by applying the model to the dissolution profile, parameters such as the precipitation rate and the potential solubility of the amorphous drug were successfully calculated. In addition, it was shown that the improvement in solubility with supersaturation was able to be evaluated quantitatively using this model. Therefore, this mathematical model would be a useful tool to quantitatively determine the supersaturation

  6. Development of a Single-Crystal Mineral Elasticity Database and Applications to Crustal and Upper Mantle Mineralogy

    NASA Astrophysics Data System (ADS)

    Duffy, T. S.

    2013-12-01

    The single-crystal elastic stiffness tensor fully characterizes the anisotropic elastic response of minerals. An understanding of how such elastic properties vary with pressure, temperature, structure, and composition are needed to interpret seismic data for the Earth. Additionally, elastic moduli are important for understanding many solid-state phenomena including mechanical stability, interatomic interactions, material strength, compressibility, and phase transition mechanisms. A database of single-crystal elastic properties of minerals and related phases is being assembled. This dataset currently incorporates over 400 sets of elastic constant measurements on more than 270 separate phases. In addition to compiling the individual elastic stiffnesses, the database also allows calculation of a variety of additional properties including anisotropy factors, bulk and linear compressibilities, and stability criteria, as well as evaluation of aggregate properties including bounds and averages of bulk, shear, Young's modulus, Poisson's ratio and elastic wave speeds. Extensions of the database to include high pressure and high temperature data as well as theoretical calculations are being planned. Examples of application of this database to geophysical problems will be highlighted. Specific applications to be discussed include: 1) variation of elastic anisotropy with pressure for mantle and crustal minerals; 2) evaluation of elasticity data for pyroxenes revealing major structural and chemical controls on elasticity as well as remaining ambiguities and uncertainties.

  7. The intrinsically disordered C-RING biomineralization protein, AP7, creates protein phases that introduce nanopatterning and nanoporosities into mineral crystals.

    PubMed

    Chang, Eric P; Russ, Jennie A; Verch, Andreas; Kröger, Roland; Estroff, Lara A; Evans, John Spencer

    2014-07-15

    We report an interesting process whereby the formation of nanoparticle assemblies on and nanoporosities within calcite crystals is directed by an intrinsically disordered C-RING mollusk shell nacre protein, AP7. Under mineralization conditions, AP7 forms protein phases that direct the nucleation of ordered calcite nanoparticles via a repetitive protein phase deposition process onto calcite crystals. These organized nanoparticles are separated by gaps or spaces that become incorporated into the forming bulk crystal as nanoporosities. This is an unusual example of organized nanoparticle biosynthesis and mineral modification directed by a C-RING protein phase.

  8. The Intrinsically Disordered C-RING Biomineralization Protein, AP7, Creates Protein Phases That Introduce Nanopatterning and Nanoporosities into Mineral Crystals

    PubMed Central

    2015-01-01

    We report an interesting process whereby the formation of nanoparticle assemblies on and nanoporosities within calcite crystals is directed by an intrinsically disordered C-RING mollusk shell nacre protein, AP7. Under mineralization conditions, AP7 forms protein phases that direct the nucleation of ordered calcite nanoparticles via a repetitive protein phase deposition process onto calcite crystals. These organized nanoparticles are separated by gaps or spaces that become incorporated into the forming bulk crystal as nanoporosities. This is an unusual example of organized nanoparticle biosynthesis and mineral modification directed by a C-RING protein phase. PMID:24977921

  9. Incorporation of Np(V) and U(VI) in carbonate and sulfate minerals crystallized from aqueous solution

    NASA Astrophysics Data System (ADS)

    Balboni, Enrica; Morrison, Jessica M.; Wang, Zheming; Engelhard, Mark H.; Burns, Peter C.

    2015-02-01

    The neptunyl Np(V)O2+ and uranyl U(VI)O22+ ions are soluble in groundwater, although their interaction with minerals in the subsurface may impact their mobility. One mechanism for the immobilization of actinyl ions in the subsurface is co-precipitation in low-temperature minerals that form naturally, or that are induced to form as part of a remediation strategy. Important differences in the crystal-chemical behavior of the Np(V) neptunyl and U(VI) uranyl ions suggest their behavior towards incorporation into growing crystals may differ significantly. Using a selection of low-temperature minerals synthesized in aqueous systems under ambient conditions, this study examines the factors that impact the structural incorporation of the Np(V) neptunyl and U(VI) uranyl ions in carbonate and sulfate minerals. Calcite (CaCO3), aragonite (CaCO3), gypsum (CaSO4·2H2O), strontianite (SrCO3), cerussite (PbCO3), celestine (SrSO4), and anglesite (PbSO4) were synthesized from aqueous solutions containing either 400-1000 ppm of U(VI) or Np(V) relative to the divalent cation present in the system. The synthetic products were investigated by inductively coupled plasma mass spectrometry, luminescence and time resolved luminescence spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. Amongst the carbonate minerals, calcite significantly favors Np(V) incorporation over U(VI). U(VI) and Np(V) are incorporated in aragonite and strontianite in similar amounts, whereas cerussite did not incorporate either U(VI) or Np(V) under the synthesis conditions. The sulfate minerals weakly interact with the actinyl ions, relative to the carbonate minerals. Incorporation of U(VI) and Np(V) in celestine was observed at the level of a few tens of ppm; anglesite and gypsum did not incorporate detectable U(VI) or Np(V). Luminescence spectra of the uranyl incorporated in aragonite and strontianite are consistent with a uranyl unit coordinated by three bidentate CO32- groups

  10. The strength of a calcified tissue depends in part on the molecular structure and organization of its constituent mineral crystals in their organic matrix

    NASA Technical Reports Server (NTRS)

    Landis, W. J.

    1995-01-01

    High-voltage electron-microscopic tomographic (3D) studies of the ultrastructural interaction between mineral and organic matrix in a variety of calcified tissues reveal different crystal structural and organizational features in association with their respective organic matrices. In brittle or weak pathologic or ectopic calcifications, including examples of osteogenesis imperfecta, calciphylaxis, calcergy, and dermatomyositis, hydroxyapatite crystals occur in various sizes and shapes and are oriented and aligned with respect to collagen in a manner which is distinct from that found in normal calcified tissues. A model of collagen-mineral interaction is proposed which may account for the observed crystal structures and organization. The results indicate that the ultimate strength, support, and other mechanical properties provided by a calcified tissue are dependent in part upon the molecular structure and arrangement of its constituent mineral crystals within their organic matrix.

  11. Dynamics of mineral crystallization at inclusion-garnet interface from precipitated slab-derived fluid phase: first in-situ synchrotron x-ray measurements

    NASA Astrophysics Data System (ADS)

    Malaspina, Nadia; Alvaro, Matteo; Campione, Marcello; Nestola, Fabrizio

    2015-04-01

    Remnants of the fluid phase at ultrahigh pressure (UHP) in subduction environments may be preserved as primary multiphase inclusions in UHP minerals. These inclusions are frequently hosted by minerals stable at mantle depths, such as garnet, and show the same textural features as fluid inclusions. The mineral infillings of the solid multiphase inclusions are generally assumed to have crystallized by precipitation from the solute load of dense supercritical fluids equilibrating with the host rock. Notwithstanding the validity of this assumption, the mode of crystallization of daughter minerals during precipitation within the inclusion and/or the mechanism of interaction between the fluid at supercritical conditions and the host mineral are still poorly understood from a crystallographic point of view. A case study is represented by garnet orthopyroxenites from the Maowu Ultramafic Complex (China) deriving from harzburgite precursors metasomatised at ~ 4 GPa, 750 °C by a silica- and incompatible trace element-rich fluid phase. This metasomatism produced poikilitic orthopyroxene and inclusion-rich garnet porphyroblasts. Solid multiphase primary inclusions in garnet display a size within a few tens of micrometers and negative crystal shapes. Infilling minerals (spinel: 10-20 vol.%; amphibole, chlorite, talc, mica: 80- 90 vol.%) occur with constant volume ratios and derive from trapped solute-rich aqueous fluids. To constrain the possible mode of precipitation of daughter minerals, we performed for the first time a single-crystal X-ray diffraction experiment by means of Synchrotron Radiation at DLS-Diamond Light Source. In combination with electron probe microanalyses, this measurement allowed the unique identification of each mineral phase and their reciprocal orientations. We demonstrated the epitaxial relationship between spinel and garnet and between some hydrous minerals. Epitaxy drives a first-stage nucleation of spinel under near-to-equilibrium conditions

  12. Crystal and molecular structure and spectroscopic behavior of isotypic synthetic analogs of the oxalate minerals stepanovite and zhemchuzhnikovite

    NASA Astrophysics Data System (ADS)

    Piro, Oscar E.; Echeverría, Gustavo A.; González-Baró, Ana C.; Baran, Enrique J.

    2016-04-01

    The crystal structure of synthetic stepanovite, Na[Mg(H2O)6][Fe(C2O4)3]·3H2O, and zhemchuzhnikovite, Na[Mg(H2O)6][Al0.55Fe0.45(C2O4)3]·3H2O, has been determined by single-crystal X-ray diffraction methods. The compounds are isotypic to each other and to the previously reported Na[Mg(H2O)6][M(C2O4)3]·3H2O (M: Cr, Al). They crystallize in the trigonal P3 c1 space group with Z = 6 molecules per unit cell and (hexagonal axes) a = 17.0483(4), c = 12.4218(4) Å for the iron compound, and a = 16.8852(5), c = 12.5368(5) Å for the Al/Fe solid solution. Comparison of our crystallographic results with previous X-ray diffraction and chemical data of type stepanovite and zhemchuzhnikovite minerals provides compelling evidence that these natural materials possess the same crystal and molecular structure as their synthetic counterparts. It is shown that the originally reported unit cell for stepanovite represents a pronounced sub-cell and that the correct unit cell and space group are based on weak superstructure reflections. The infrared and Raman spectra of both synthetic analogs were also recorded and are briefly discussed.

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

    NASA Astrophysics Data System (ADS)

    Nielsen, T. F.; Bernstein, S.

    2009-12-01

    density and densities of melt and liquidus phases suggest plag to have neutral buoyancy (floating), whereas all other phases would sink. The repeated successions are suggested to be the result of repeated “self-stratification” in the mush zone at the crystallization front, characterized by separation of px and plag leaving a transitional zone enriched in Fe-rich melt. In this melt, crystallization of mt led to S-saturation and formation of immiscible sulfide globules (30µm) in which PGE-minerals crystallize. During solidification, residual or immiscible Si-rich melt and volatiles rose from the transitional zone and took Au, Ag, Pt, Te, As, Pb, Sb, Sn, a.o. along to the main magma above and at late stage to granophyric veins. The Fe-enriched gabbros in the transitional zone are commonly accepted as average gabbros, but are in the Triple Group mixes of cumulus phases and evolved Fe-rich melt and should be used with care in the modeling of lines of liquid descent.

  14. Deducing growth mechanisms for minerals from the shapes of crystal size distributions

    USGS Publications Warehouse

    Eberl, D.D.; Drits, V.A.; Srodon, J.

    1998-01-01

    Crystal size distributions (CSDs) of natural and synthetic samples are observed to have several distinct and different shapes. We have simulated these CSDs using three simple equations: the Law of Proportionate Effect (LPE), a mass balance equation, and equations for Ostwald ripening. The following crystal growth mechanisms are simulated using these equations and their modifications: (1) continuous nucleation and growth in an open system, during which crystals nucleate at either a constant, decaying, or accelerating nucleation rate, and then grow according to the LPE; (2) surface-controlled growth in an open system, during which crystals grow with an essentially unlimited supply of nutrients according to the LPE; (3) supply-controlled growth in an open system, during which crystals grow with a specified, limited supply of nutrients according to the LPE; (4) supply- or surface-controlled Ostwald ripening in a closed system, during which the relative rate of crystal dissolution and growth is controlled by differences in specific surface area and by diffusion rate; and (5) supply-controlled random ripening in a closed system, during which the rate of crystal dissolution and growth is random with respect to specific surface area. Each of these mechanisms affects the shapes of CSDs. For example, mechanism (1) above with a constant nucleation rate yields asymptotically-shaped CSDs for which the variance of the natural logarithms of the crystal sizes (??2) increases exponentially with the mean of the natural logarithms of the sizes (??). Mechanism (2) yields lognormally-shaped CSDs, for which ??2 increases linearly with ??, whereas mechanisms (3) and (5) do not change the shapes of CSDs, with ??2 remaining constant with increasing ??. During supply-controlled Ostwald ripening (4), initial lognormally-shaped CSDs become more symmetric, with ??2 decreasing with increasing ??. Thus, crystal growth mechanisms often can be deduced by noting trends in ?? versus ??2 of CSDs for

  15. Measuring water adsorption on mineral surfaces in air, CO2, and supercritical CO2 with a quartz-crystal microbalance

    NASA Astrophysics Data System (ADS)

    Bryan, C. R.; Wells, R. K.; Burton, P. D.; Heath, J. E.; Dewers, T. A.; Wang, Y.

    2011-12-01

    Carbon sequestration via underground storage in geologic formations is a proposed approach for reducing industrial CO2 emissions. However, current models for carbon injection and long-term storage of supercritical CO2 (scCO2) do not consider the development and stability of adsorbed water films at the scCO2-hydrophilic mineral interface. The thickness and properties of the water films control the surface tension and wettability of the mineral surface, and on the core scale, affect rock permeability, saturation, and capillary properties. The film thickness is strongly dependent upon the activity of water in the supercritical fluid, which will change as initially anhydrous scCO2 absorbs water from formation brine. As described in a companion paper by the coauthors, the thickness of the adsorbed water layer is controlled by the disjoining pressure; structural and van der Waals components dominate at low water activity, while electrostatic forces become more important with increasing film thickness (higher water activities). As scCO2 water activity and water layer thickness increase, concomitant changes in mineral surface properties and reservoir/caprock hydrologic properties will affect the mobility of the aqueous phase and of scCO2. Moreover, the development of a water layer may be critical to mineral dissolution reactions in scCO2. Here, we describe the use of a quartz-crystal microbalance (QCM) to monitor adsorption of water by mineral surfaces. QCMs utilize a piezoelectrically-stimulated quartz wafer to measure adsorbed or deposited mass via changes in vibrational frequency. When used to measure the mass of adsorbed liquid films, the frequency response of the crystal must be corrected for the viscoelastic, rather than elastic, response of the adsorbed layer. Results are presented for adsorption to silica in N2 and CO2 at one bar, and in scCO2. Additional data are presented for water uptake by clays deposited on a QCM wafer. In this case, water uptake occurs by the

  16. Depth-Sensing Indentation on REBa2Cu3O7-δ Single Crystals Obtained from Xenotime Mineral

    NASA Astrophysics Data System (ADS)

    Serbena, Francisco Carlos; Foerster, Carlos Eugênio; Jurelo, Alcione Roberto; Mikowski, Alexandre; Júnior, Pedro Rodrigues; Carubelli, Célia Regina; Lepienski, Carlos Maurício

    2012-12-01

    A natural mixture of heavy rare-earth oxides extracted from xenotime mineral have been used to prepare large single crystals of the high-temperature REBa2Cu3O7-δ superconductor, grown using the CuO-BaO self-flux method. Its mechanical properties along the ab-plane were characterized using instrumented indentation. Hardness and elastic moduli were measured by the Oliver and Pharr method, which yielded 7.4 ± 0.2 GPa and the range 135-175 GPa at small depths, respectively. Increased loads promote the nucleation of lateral cracks, which reduce hardness and measured elastic modulus, as indicated by instrumented indentation at higher loads. The indentation fracture toughness, estimated by measuring the radial crack length from cube corner indentations at various loads, was found to be 0.8 ± 0.2 MPa m1/2. The observed slip systems of REBa2Cu3O7-δ single crystals were [100](001) and [010](001), the same as for YBa2Cu3O7-δ single crystals. The initial stages of deformation and fracture in the indentation process were investigated. The hardness and elastic modulus are not strongly modified by the crystallographic orientation in the ab-plane. This was interpreted in terms of resolved shear stresses in the active slip systems. Evidence of cracking along the {100} and {110} planes on the ab-plane was observed. In conclusion, the mechanical properties of REBa2Cu3O7-δ single crystals prepared from xenotime are equivalent to those of YBa2Cu3O7-δ single crystals from conventional rare-earth oxides.

  17. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic, geophysical, geochemical, mineral-occurrence, mineral-resource potential, and mineral-production maps of the Charlotte 1 degree x 2 degrees Quadrangle, North Carolina and South Carolina

    USGS Publications Warehouse

    Gair, Jacob Eugene; Goldsmith, Richard; Daniels, D.L.; Griffitts, W.R.; DeYoung, J.H.; Lee, M.P.

    1986-01-01

    This Circular and the folio of separately published maps described herein are part of a series of reports compiled under the Conterminous United States Mineral Assessment Program ICUSMAP). The folio on the Charlotte 1 degree ? 2 degree quadrangle, North Carolina and South Carolina, includes (1) a geologic map; (2) four geophysical maps; (3) geochemical maps for metamorphic heavy minerals, copper, lead and artifacts, zinc, gold, tin, beryllium, niobium, tungsten, molybdenum, titanium, cobalt, lithium, barium, antimony-arsenic-bismuth-cadmium, thorium-cerium-monazite, and limonite; (4) mineral-occurrence maps for kyanite-sillimanite-lithium-mica-feldspar-copper-lead-zinc, gold-quartz-barite-fluorite, iron-thorium-tin-niobium, and construction materials-gemstones; (5) mineral-resource potential maps for copper-lead-zinc-combined base metals, gold, tin-tungsten, beryllium-molybdenum-niobium, lithium-kyanite- sillimanitebarite, thorium (monazite)-uranium, and construction materials; and (6) mineral-production maps. The Charlotte quadrangle is mainly within the Piedmont physiographic province and extends from near the Coastal Plain on the southeast into the Blue Ridge province on the northwest for a short distance. Parts of six lithotectonic belts are present--the Blue Ridge, the Inner Piedmont, the Kings Mountain belt, the Charlotte belt, the Carolina slate belt, and the Wadesboro basin. Igneous, metamorphic, and sedimentary rocks are present and range in age from Proterozoic to Mesozoic; alluvial sediments of Quaternary age occur along rivers and larger streams. Rocks of the Blue Ridge include Middle Proterozoic granitoid gneiss intruded by Late Proterozoic granite; Late Proterozoic paragneiss, schist, and other metasedimentary and metavolcaniclastic rocks (Ashe and Grandfather Mountain Formations); Late Proterozoic and Early Cambrian metasedimentary rocks (Chilhowee Group); and Early Cambrian sedimentary rocks (Shady Dolomite). Paleozoic granites intrude the

  18. Rocks and Minerals.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Provides background information on rocks and minerals, including the unique characteristics of each. Teaching activities on rock-hunting and identification, mineral configurations, mystery minerals, and growing crystals are provided. Reproducible worksheets are included for two of the activities. (TW)

  19. The use of mineral crystals as bio-markers in the search for life on Mars.

    PubMed

    Schwartz, D E; Mancinelli, R L; Kaneshiro, E S

    1992-01-01

    Photographs that depict presumed fluvial features on the martian surface have led geologists to hypothesize that water flowed across the early martian terrain. From this, it has been further hypothesized that the surface and atmospheric conditions on early Mars were similar to those on early Earth. Because the oldest fossil evidence of life on Earth dates back to this early period, at least 3.5 billion years ago, the possibility exists that the early Martian environment could have also been conducive to the origin of life. To investigate this possibility, universal signatures or bio-markers indicative of past (or present) biological activity must be identified for use in the search for life on Mars. Several potentially applicable biomarkers have been identified and include: organics (e.g., specific classes of lipids and hopanes), suites of specific inorganic and organic compounds, as well as the isotopic ratios of C, N, and S. Unfortunately, all of these bio-markers may be of biologic or abiotic origin; these origins are often difficult to distinguish. Thus, the discovery of any one of these compounds alone is not a bio-marker. Because minerals produced under biologic control have distinctive crystallographies, morphologies, and isotopic ratios that distinguishable from abiotically produced minerals with the same chemical composition, and are stable through geologic time, we propose the use of minerals resulting from biologically controlled mineralization processes as bio-markers.

  20. Description and crystal structure of nyholmite, a new mineral related to hureaulite, from Broken Hill, New South Wales, Australia

    SciTech Connect

    Elliott, P.; Turner, P.; Jensen, P.; Kolitsch, U.; Pring, A.

    2010-08-12

    Nyholmite, Cd{sub 3}Zn{sub 2}(AsO{sub 3}OH){sub 2}(AsO{sub 4}){sub 2} {center_dot} 4H{sub 2}O, from the Block 14 Opencut, Broken Hill, New South Wales, Australia, is a new Cd-Zn arsenate species, isostructural with the minerals of the hureaulite group. The mineral occurs in a quartz-garnet-arsenopyrite matrix as white globules, tufted aggregates of fibrous crystals and radiating hemispheres of thin, colourless, bladed crystals. Associated minerals are goldquarryite, lavendulan-sampleite, scorodite-strengite and gypsum. Individual crystals are up to 0.2 mm in length and 0.05 mm across. The mineral is transparent to translucent with a vitreous lustre. It is brittle with an uneven fracture and a white streak. The Mohs hardness is 3-3.5 and the calculated density is 4.23 g cm{sup -3} for the empirical formula. Electron microprobe analyses yielded CdO 34.58, ZnO 9.72, MnO 3.59, CuO 3.39, Al{sub 2}O{sub 3} 0.20, CaO 0.16, PbO 0.37, As{sub 2}O{sub 5} 34.55, P{sub 2}O{sub 5} 6.29 totalling 92.85 wt.%. The empirical formula, based on 20 oxygen atoms, is Ca{sub 0.03}Pb{sub 0.02} Cd{sub 2.80}Al{sub 0.04}Zn{sub 1.24}-Cu{sub 0.44}Mn{sub 0.53}[(AsO{sub 4}){sub 3.13}(PO{sub 4}){sub 0.92}]{Sigma}{sub 4.05}H{sub 1.91} {center_dot} 3.79H{sub 2}O. Nyholmite is monoclinic, C2/c, a = 18.062(4) {angstrom}, b = 9.341(2) {angstrom}, c = 9.844(2) {angstrom}, {beta} = 96.17(3){sup o}, V = 1651.2(6) {angstrom}{sup 3} (single-crystal data, at 123 K). The six strongest lines in the X-ray powder diffraction pattern are [d({angstrom}),I,(hkl)]: 8.985,30,(200); 8.283, 85,(110); 6.169,25,(111); 4.878,25,(002); 3.234,100,(222, 420); 3.079,65,(222, 511); 2.976,45,(113). The crystal structure was solved by Patterson methods and refined using 2045 observed reflections to R1(F) = 3.73%. The structure is characterized by a kinked, five-membered chain of edge-sharing M{phi}{sub 6} ({phi} = unspecified anion) octahedra, or pentamer, that extends in the a direction. The pentamers link by sharing corners to

  1. Crystal-field-driven redox reactions: How common minerals split H2O and CO2 into reduced H2 and C plus oxygen

    NASA Technical Reports Server (NTRS)

    Freund, F.; Batllo, F.; Leroy, R. C.; Lersky, S.; Masuda, M. M.; Chang, S.

    1991-01-01

    It is difficult to prove the presence of molecular H2 and reduced C in minerals containing dissolved H2 and CO2. A technique was developed which unambiguously shows that minerals grown in viciously reducing environments contain peroxy in their crystal structures. The peroxy represent interstitial oxygen atoms left behind when the solute H2O and/or CO2 split off H2 and C as a result of internal redox reactions, driven by the crystal field. The observation of peroxy affirms the presence of H2 and reduced C. It shows that the solid state is indeed an unusual reaction medium.

  2. A new mineral species rossovskyite, (Fe3+,Ta)(Nb,Ti)O4: crystal chemistry and physical properties

    NASA Astrophysics Data System (ADS)

    Konovalenko, Sergey I.; Ananyev, Sergey A.; Chukanov, Nikita V.; Rastsvetaeva, Ramiza K.; Aksenov, Sergey M.; Baeva, Anna A.; Gainov, Ramil R.; Vagizov, Farit G.; Lopatin, Oleg N.; Nebera, Tatiana S.

    2015-11-01

    A new mineral rossovskyite named after L.N. Rossovsky was discovered in granite pegmatites of the Bulgut occurrence, Altai Mts., Western Mongolia. Associated minerals are microcline, muscovite, quartz, albite, garnet of the almandine-spessartine series, beryl, apatite, triplite, zircon, pyrite, yttrobetafite-(Y) and schorl. Rossovskyite forms flattened anhedral grains up to 6 × 6 × 2 cm. The color of the mineral is black, and the streak is black as well. The luster is semi-metallic, dull. Mohs hardness is 6. No cleavage or parting is observed. Rossovskyite is brittle, with uneven fracture. The density measured by the hydrostatic weighing method is 6.06 g/cm2, and the density calculated from the empirical formula is 6.302 g/cm3. Rossovskyite is biaxial, and the color in reflection is gray to dark gray. The IR spectrum contains strong band at 567 cm-1 (with shoulders at 500 and 600 cm-1) corresponding to cation-oxygen stretching vibrations and weak bands at 1093 and 1185 cm-1 assigned as overtones. The reflection spectrum in visible range is obtained. According to the Mössbauer spectrum, the ratio Fe2+:Fe3+ is 35.6:64.4. The chemical composition is as follows (electron microprobe, Fe apportioned between FeO and Fe2O3 based on Mössbauer data, wt%): MnO 1.68, FeO 5.92, Fe2O3 14.66, TiO2 7.69, Nb2O5 26.59, Ta2O5 37.51, WO3 5.61, total 99.66. The empirical formula calculated on four O atoms is: {{Mn}}_{0.06}^{2 + } {{Fe}}_{0.21}^{2 + } {{Fe}}_{0.47}^{3 + } Ti0.25Nb0.51Ta0.43W0.06O4. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is monoclinic, space group P2/ c, a = 4.668(1), b = 5.659(1), c = 5.061(1) Å, β = 90.21(1)º; V = 133.70(4) Å3, Z = 2. Topologically, the structure of rossovskyite is analogous to that of wolframite-group minerals. The crystal-chemical formula of rossovskyite is [(Fe3+, Fe2+, Mn)0.57Ta0.32Nb0.11][Nb0.40Ti0.25Fe0.18Ta0.11W0.06]O4. The strongest lines of the powder X-ray diffraction pattern

  3. The effect of crystal plasticity and mineral stability on the rheological properties of magma during spine extrusion at Unzen, Japan

    NASA Astrophysics Data System (ADS)

    Wallace, Paul A.; Kendrick, Jackie E.; Lavallée, Yan; Ashworth, James D.; Mariani, Elisabetta; von Aulock, Felix W.; Coats, Rebecca; Miwa, Takahiro

    2016-04-01

    and microlites, with biotite displaying the greatest evidence of strain accommodation. This permanent strain is induced when the shear stress exceeds a critical point on an orientated lattice plane, resulting in a misorientation of the internal lattice. Crystal-plastic behaviour may thus act as a strain marker for the viscous-brittle transition during ascent. In the highly sheared zone, the rims of both hydrous minerals (hornblende and biotite) and plagioclase show a reaction with the melt suggesting disequilibrium conditions - a feature not as evident in the undeformed magmatic core of the spine. The narrow localisation of the disequilibrium textures suggest that the increased effects of gas flow in the permeable shear zone and/or thermal input due to strain localisation may be contributing factors affecting mineral stability during magma transport. These deformation microstructures that occur in the shallow conduit, especially during ascent of highly viscous magma, can lead to permeability anisotropy which can significantly alter degassing efficiency and control the explosivity of an eruption. For this reason a thorough petrological/rheological understanding of these deformation processes is vital in constraining the complexities associated with on-going eruptions and shifts from effusive to explosive activity.

  4. Evolutionary crystal structure prediction: discovering new minerals in the deep Earth.

    NASA Astrophysics Data System (ADS)

    Oganov, A. R.; Glass, C. W.

    2006-12-01

    Experimental determination of crystal structures at high pressure is often extremely difficult; given this and the strengths of quantum-mechanical simulations, theory presents an attractive tool to investigate matter at extreme conditions. However, crystal structure prediction on the basis of just the chemical formula has long been considered a formidable or even insoluble problem. Solving it would enable structural studies of planetary materials at extreme conditions [1,2] and probe changing chemistry at high pressure, solve structures where experimental data are insufficient, and design new materials entirely on the computer (once the structure is known, it is relatively easy to predict many of its properties e.g., [3]). Recently, we addressed this problem and devised a new method based on an ab initio evolutionary algorithm, which we implemented in the USPEX code (Universal Structure Predictor: Evolutionary Xtallography, [4-6]). USPEX uses ab initio free energy as evaluation function and features local optimization and spatial heredity, as well as further operators such as mutation and permutation. At given P-T conditions, USPEX finds the stable structure and a set of robust metastable structures, using no experimental information except the chemical composition. This method has been widely tested and applied to solve a number of important problems. In this talk I will discuss some of the applications of this method to a number of interesting materials at high pressure (C, O, S, MgSiO3, CO2, CaCO3, MgCO3). 1. Oganov A.R. & Ono S. (2004). Theoretical and experimental evidence for a post-perovskite phase of MgSiO3 in Earth's D" layer. Nature 430, 445-448. 2. Oganov A.R., Ono S. (2005). The high pressure phase of alumina and implications for Earth's D" layer. Proc. Natl. Acad. Sci. 102, 10828-10831. 3. Oganov A.R., Brodholt J.P., Price G.D. (2001). The elastic constants of MgSiO3 perovskite at pressures and temperatures of the Earth's mantle. Nature 411, 934-937. 4

  5. Filaments in Carbonaceous Meteorites: Mineral Crystals, Modern Bio-Contaminants or Indigenous Microfossils of Trichomic Prokaryotes?

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Borisyak, A. A.

    2011-01-01

    Environmental (ESEM) and Field Emission Scanning Electron Microscopy (FESEM) investigations have resulted in the detection of a large number of complex filaments in a variety of carbonaceous meteorites. Many of the filaments were observed to be clearly embedded the rock matrix of freshly fractured interior surfaces of the meteorites. The high resolution images obtained combined with tilt and rotation of the stage provide 3-dimensional morphological and morphometric data for the filaments. Calibrated Energy Dispersive X-ray Spectroscopy (EDS) and 2-D elemental X-ray maps have provided information on the chemical compositions of the filaments and the minerals of the associated meteorite rock matrix. These observations are used to evaluate diverse hypotheses regarding the possible abiotic or biogenic nature of the filaments found embedded in these meteorites.

  6. Mineral chemistry, crystallization conditions and geodynamic implications of the Oligo-Miocene granitoids in the Biga Peninsula, Northwest Turkey

    NASA Astrophysics Data System (ADS)

    Aysal, Namık

    2015-06-01

    Widespread plutonic rocks in NW Turkey occur within the southward-younging and overlapping magmatic belts across the Aegean region. Post-collisional magmatism is represented by a series of granitoidic intrusions and volcanic successions. K-Ar and U-Pb LA-ICP-MS zircon dating of the Kazdağ and Yenice plutons yielded ages between 20.5 ± 0.5 Ma and 27.89 ± 0.17 Ma (Late Oligocene-Early Miocene). The granitoid samples are high-K calc-alkaline and metaluminous to slightly peraluminous. The 87Sr/86Sr values for the granitoids, enclaves and leucocratic rocks range between 0.705168 and 0.708357. The initial 143Nd/144Nd ratios calculated for the crystallization ages of ca. 23-27 Ma are between 0.512425 and 0.512614, and the εNd values vary from -3.5 to 0.2. The Nd TDM model ages range between 0.73 and 1.13 Ga. These samples are enriched in LILEs and LREE and depleted in HFSEs with negative Eu anomalies, indicating that the melts were derived from an enriched lithospheric mantle modified by subducted slab-derived melts. Energy constrained-assimilation and fractional crystallization (EC-AFC) modelling indicates that fractional crystallization and crustal assimilation modified the parent magma's composition during its residence in the upper crust. The mineral chemistry of amphiboles, pyroxenes, biotites and feldspars is used to constrain the pressure (P), temperature (T), oxygen fugacity (logƒO2) and water contents (H2Omelt) during the crystallization of the magmas in the studied granitoids. The clinopyroxene temperatures are in the range of 823-910 ± 45 °C. The amphibole temperatures for the studied plutonic rocks are in the range of 707-926 °C (mean = 798 ± 45 °C), and the crystallization depths are estimated to be in the interval of 1.02-10.2 km. The NW Anatolian plutonic rocks can be considered to have been equilibrated at the oxygen fugacities of calcic amphiboles (logƒO2) between -8.99 and -13.96 bars (mean = -12.11 bar) and H2Omelt contents between 1.63% and

  7. Mineral chemical compositions of late Cretaceous volcanic rocks in the Giresun area, NE Turkey: Implications for the crystallization conditions

    NASA Astrophysics Data System (ADS)

    Oǧuz, Simge; Aydin, Faruk; Uysal, İbrahim; Şen, Cüneyt

    2016-04-01

    This contribution contains phenocryst assemblages and mineral chemical data of late Cretaceous volcanic (LCV) rocks from the south of Görele and Tirebolu areas (Giresun, NE Turkey) in order to investigate their crystallization conditions. The LCV rocks in the study area occur in two different periods (Coniasiyen-Early Santonian and Early-Middle Campanian), which generally consist of alternation of mafic-intermediate (basaltic to andesitic) and felsic rock series (dacitic and rhyolitic) within each period. The basaltic and andesitic rocks in both periods generally exhibit porphyritic to hyalo-microlitic porphyritic texture, and contain phenocrysts of plagioclase and pyroxene, whereas the dacitic and rhyolitic rocks of the volcanic sequence usually show a vitrophyric texture with predominant plagioclase, K-feldspar, quartz and lesser amphibole-biotite phenocrysts. Zoned plagioclase crystals of the mafic and felsic rocks in different volcanic periods are basically different in composition. The compositions of plagioclase in the first-stage mafic rocks range from An52 to An78 whereas those of plagioclase from the first-stage felsic rocks have lower An content varying from An38 to An50. Rim to core profile for the zoned plagioclase of the first-stage mafic rocks show quite abrupt and notable compositional variations whereas that of the first-stage felsic rocks show slight compositional variation, although some of the grains may display reverse zoning. On the other hand, although no zoned plagioclase phenocryst observed in the second-stage mafic rocks, the compositions of microlitic plagioclase show wide range of compositional variation (An45-80). The compositions of zoned plagioclase in the second-stage felsic rocks are more calcic (An65-81) than those of the first-stage felsic rocks, and their rim to core profile display considerable oscillatory zoning. The compositions of pyroxenes in the first- and second-stage mafic-intermediate rocks vary over a wide range from

  8. Crystallizing the function of the magnetosome membrane mineralization protein Mms6

    PubMed Central

    Staniland, Sarah S.; Rawlings, Andrea E.

    2016-01-01

    The literature on the magnetosome membrane (MM) protein, magnetosome membrane specific6 (Mms6), is reviewed. Mms6 is native to magnetotactic bacteria (MTB). These bacteria take up iron from solution and biomineralize magnetite nanoparticles within organelles called magnetosomes. Mms6 is a small protein embedded on the interior of the MM and was discovered tightly associated with the formed mineral. It has been the subject of intensive research as it is seen to control the formation of particles both in vivo and in vitro. Here, we compile, review and discuss the research detailing Mms6’s activity within the cell and in a range of chemical in vitro methods where Mms6 has a marked effect on the composition, size and distribution of synthetic particles, with approximately 21 nm in size for solution precipitations and approximately 90 nm for those formed on surfaces. Furthermore, we review and discuss recent work detailing the structure and function of Mms6. From the evidence, we propose a mechanism for its function as a specific magnetite nucleation protein and summaries the key features for this action: namely, self-assembly to display a charged surface for specific iron binding, with the curvature of the surfaces determining the particle size. We suggest these may aid design of biomimetic additives for future green nanoparticle production. PMID:27284056

  9. Role of magma pressure, tectonic stress and crystallization progress in the emplacement of syntectonic granites. The A-type Estrela Granite Complex (Carajás Mineral Province, Brazil)

    NASA Astrophysics Data System (ADS)

    Barros, C. E. M.; Barbey, P.; Boullier, A. M.

    2001-12-01

    The Archaean, syntectonic, A-type Estrela Granite Complex (Carajás Mineral Province, Brazil) consists of three plutons emplaced in a greenstone sequence under low-pressure conditions (180< P<310 MPa). It is composed mainly of annite-, ferropargasite (±hedenbergite)- and ilmenite-bearing monzogranites. The contact aureole is affected by a subvertical penetrative schistosity conformable with the limits of the plutons. Meso- to microstructures and mineral reactions in the granites indicate that deformation occurred in a continuum from above-solidus to low- T subsolidus conditions. Two distinct planar structures are observed: (i) a concentrical primary foliation (S 0) corresponding to rhythmic, isomodal, phase layering associated with a faint grain shape fabric; it is horizontal in the centre and vertical towards the edges of the plutons; and (ii) a steep to subvertical foliation (S 1) associated with the deformation of S 0 and accompanied with emplacement of synplutonic dykes and veins of leucocratic granites and pegmatites. Emplacement, differentiation and consolidation of the Estrela Granite Complex are considered to result from a continuous evolution under decreasing temperatures in a single-stage strained crust (transpression), with two main periods. (1) The first period is controlled by body forces, and it corresponds to inflation with magma ponding. As long as the rheology is melt dominated, magma pressure is the critical parameter and almost no strain is recorded. With decreasing T, magmas crystallize and differentiate leading to a concentrical magmatic phase layering. The growing magmatic bodies are mechanically decoupled from the country rocks and their evolution depends on internal magma chamber processes. (2) For higher amount of crystallization (residual melt fraction F<0.5), the role of magma pressure becomes insignificant. Establishment of a continuous crystal framework leads to the coupling of plutons with their surroundings, and deformation in

  10. Studies of Quaternary saline lakes-III. Mineral, chemical, and isotopic evidence of salt solution and crystallization processes in Owens Lake, California, 1969-1971

    USGS Publications Warehouse

    Smith, G.I.; Friedman, I.; McLaughlin, R.J.

    1987-01-01

    As a consequence of the 1969-1970 flooding of normally dry Owens Lake, a 2.4-m-deep lake formed and 20% of the 2-m-thick salt bed dissolved in it. Its desiccation began August 1969, and salts started crystallizing September 1970, ending August 1971. Mineralogic, brine-composition, and stable-isotope data plus field observations showed that while the evolving brine composition established the general crystallization timetable and range of primary and secondary mineral assemblages, it was the daily, monthly, and seasonal temperature changes that controlled the details of timing and mineralogy during this depositional process. Deuterium analyses of lake brine, interstitial brine, and hydrated saline phases helped confirm the sequence of mineral crystallizations and transformations, and they documented the sources and temperatures of waters involved in the reactions. Salts first crystallized as floating rafts on the lake surface. Natron and mirabilite, salts whose solubilities decrease greatly with lowering temperatures, crystallized late at night in winter, when surface-water temperatures reached their minima; trona, nahcolite, burkeite, and halite, salts with solubilities less sensitive to temperature, crystallized during the afternoon in summer, when surface salinities reached their maxima. However, different temperatures were generally associated with crystallization (at the surface) and accumulation (on the lake floor) because short-term temperature changes were transmitted to surface and bottom waters at different rates. Consequently, even when solubilities were exceeded at the surface, salts were preserved or not as a function of bottom-water temperatures. Halite, a nearly temperature-insensitive salt, was always preserved. Monitoring the lake-brine chemistry and mineralogy of the accumulating salts shows: (1) An estimated 0.9 ?? 106 tons of CO2 was released to the atmosphere or consumed by the lake's biomass prior to most salt crystallization. (2) After

  11. Aluminium phosphate and phosphate-sulphate minerals in kyanite schists of the Ichetuyskoye area, West Transbaikalia, Russia: crystal chemistry and evolution

    NASA Astrophysics Data System (ADS)

    Izbrodin, Ivan A.; Ripp, German S.; Doroshkevich, Anna G.

    2011-01-01

    Aluminium phosphate and aluminium phosphate-sulphate (APS) minerals occur as disseminated crystals and fine-grained aggregates in kyanite schists near Ichetuyskoye, in the Dzhida basin (West Transbaikal region, Russia). Petrographical, mineralogical and geochemical data suggest a metamorphic evolution through prograde and retrograde stages. Lazulite-scorzalite and trolleite in association with kyanite, quartz, muscovite, paragonite, topaz, rutile, magnetite and hematite formed during the prograde stage. More than 25 minerals identified in schists are genetically related to the retrograde stage. Some phosphates and all of the APS minerals belong to the alunite, beudantite and plumbogummite groups. Electron-microprobe data reveal the presence of wide compositional variations and complex solid-solution series among the members. The main crystal-chemical variations of the APS solid-solution series in the alunite supergroup concern the relative proportions of svanbergite, woodhouseite, goyazite, crandallite, florencite-(Ce) and natroalunite. Chemical analyses of APS minerals indicate extremely high amounts of LREE, Sr, Ba, Ca and Na. In some cases, APS minerals have compositions of Ba and Ca,Ba phosphates- sulphates.

  12. The X-ray crystal structure of Shewanella oneidensis OmcA reveals new insight at the microbe-mineral interface

    SciTech Connect

    Edwards, Marcus; Baiden, Nanakow; Johs, Alexander; Tomanicek, Stephen J.; Liang, Liyuan; Shi, Liang; Fredrickson, Jim K.; Zachara, John M.; Gates, Andrew J.; Butt, Julea N.; Richardson, David; Clarke, Thomas A.

    2014-05-21

    The x-ray crystal structure of Shewanella oneidensis OmcA, an extracellular decaheme cytochrome involved in mineral reduction, was solved to a resolution of 2.7 Å. The four OmcA molecules in the asymmetric unit were arranged so the distance between heme-5 on adjacent OmcA monomers was less than 1 nm, indicative of a transient OmcA dimer capable of intermolecular electron transfer. A previously identified hematite binding motif was identified near heme 10, forming a hydroxylated surface that would bring a heme-10 electron egress site to ~ 1 nm of mineral surface.

  13. Crystal chemistry and application development of uranyl extended structure and nanoscale materials and actinyl ion-substituted mineral phases

    NASA Astrophysics Data System (ADS)

    Wylie, Ernest M.

    The worldwide use of nuclear energy presents both significant advantages and challenges for society. Actinide research seeks to address these challenges and drive advancement in the fields of nuclear science and engineering. Here, key aspects of the fuel cycle are examined from both a fundamental and an applications-based perspective. Hydrothermal, ionothermal, room-temperature evaporation, and liquid diffusion synthesis techniques and single-crystal X-ray diffraction were used to study the structures of 18 uranyl compounds and six actinyl-doped mineral phases. These compounds represent a diverse group ranging from unique molecular clusters to novel and known extended structures isolated from aqueous and ionic liquid media. Ultrafiltration techniques were utilized to separate uranyl peroxide nanoclusters from complex aqueous solutions. Inductively coupled plasma optical emission spectroscopy and mass spectrometry were used to quantify elemental distributions in the feed and permeate solutions while Raman spectroscopy, small-angle X-ray scattering, and electrospray ionization mass spectrometry were used to define the characteristics of the cluster species across a range different solution conditions.

  14. Inferring the effects of compositional boundary layers on crystal nucleation, growth textures, and mineral chemistry in natural volcanic tephras through submicron-resolution imaging

    NASA Astrophysics Data System (ADS)

    Zellmer, Georg; Sakamoto, Naoya; Hwang, Shyh-Lung; Matsuda, Nozomi; Iizuka, Yoshiyuki; Moebis, Anja; Yurimoto, Hisayoshi

    2016-09-01

    Crystal nucleation and growth are first order processes captured in volcanic rocks and record important information about the rates of magmatic processes and chemical evolution of magmas during their ascent and eruption. We have studied glass-rich andesitic tephras from the Central Plateau of the Southern Taupo Volcanic Zone by electron- and ion-microbeam imaging techniques to investigate down to sub-micrometre scale the potential effects of compositional boundary layers (CBLs) of melt around crystals on the nucleation and growth of mineral phases and the chemistry of crystal growth zones. We find that CBLs may influence the types of mineral phases nucleating and growing, and growth textures such as the development of swallowtails. The chemistry of the CBLs also has the capacity to trigger intermittent overgrowths of nanometre-scale bands of different phases in rapidly growing crystals, resulting in what we refer to as cryptic phase zoning. The existence of cryptic phase zoning has implications for the interpretation of microprobe compositional data, and the resulting inferences made on the conditions of magmatic evolution. Identification of cryptic phase zoning may in future lead to more accurate thermobarometric estimates and thus geospeedometric constraints. In future, a more quantitative characterization of CBL formation and its effects on crystal nucleation and growth may contribute to a better understanding of melt rheology and magma ascent processes at the onset of explosive volcanic eruptions, and will likely be of benefit to hazard mitigation efforts.

  15. The Midcontinent Strategic and Critical Minerals Project; summary and background information to accompany folio of maps of the northern Midcontinent area, latitude 36-46 degrees N. and longitude 88-100 degrees W.

    USGS Publications Warehouse

    Pratt, Walden P.

    1995-01-01

    The Midcontinent Strategic and Critical Minerals Project was a broad investigation into the mineral-resource potential of the northern Midcontinent region of the United States. One product of the project is a folio of 10 sets of maps and one set of cross sections, all at a scale of 1:1,000,000, showing several subsurface geologic aspects of the region. This report summarizes the history of the multi-state cooperative project and the general content of the 11 map publications, and gives a visual sense of the scope and content of the folio through page-size samples of each of the map products.

  16. Natural mineral water of the United States: Section in Fourteenth Annual Report of the United States Geological Survey to the Secretary of the Interior, 1892-1893: Part 2 - Accompanying papers

    USGS Publications Warehouse

    Peale, A.C.

    1894-01-01

    Aside from the geological interest attached to the subject of mineral waters the facts that within the limits of the United States there are between 8,000 and 10,000 mineral springs, and that the waters from nearly 300 are annually placed upon the market to the extent of over 21,000,000 gallons, at a valuation of nearly \\$5,000,000, show plainly that the subject is also one of considerable economic importance. That this importance is an increasing one is evident when a comparison of these figures is made with the figures for 1883, the first year they were compiled. The production then was 7,529,423 gallons, with a valuation of \\$1,119,603, and the total number of springs known to be utilized for commercial purposes was only 189.

  17. 30 CFR 250.215 - What hydrogen sulfide (H2S) information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What hydrogen sulfide (H2S) information must accompany the EP? 250.215 Section 250.215 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... Contents of Exploration Plans (ep) § 250.215 What hydrogen sulfide (H2S) information must accompany the...

  18. 30 CFR 250.228 - What administrative information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What administrative information must accompany the EP? 250.228 Section 250.228 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... Contents of Exploration Plans (ep) § 250.228 What administrative information must accompany the EP?...

  19. 30 CFR 250.223 - What mitigation measures information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What mitigation measures information must accompany the EP? 250.223 Section 250.223 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... Contents of Exploration Plans (ep) § 250.223 What mitigation measures information must accompany the EP?...

  20. 30 CFR 250.222 - What lease stipulations information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What lease stipulations information must accompany the EP? 250.222 Section 250.222 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... Contents of Exploration Plans (ep) § 250.222 What lease stipulations information must accompany the EP?...

  1. Crystallization conditions and controls on trace element residence in the main minerals from the Pedra Branca Syenite, Brazil: An electron microprobe and LA-ICPMS study

    NASA Astrophysics Data System (ADS)

    Carvalho, Bruna Borges; Janasi, Valdecir de Assis

    2012-11-01

    Major and trace-element microanalyses of the main minerals from the 610 Ma Pedra Branca Syenite, southeast Brazil, allow inferences on intensive parameters of magmatic crystallization and on the partition of trace-elements among these minerals, with important implications for the petrogenetic evolution of the pluton. Two main syenite types make up the pluton, a quartz-free syenite with tabular alkali feldspar (laminated silica-saturated syenite, LSS, with Na-rich augite + phlogopite + hematite + magnetite + titanite + apatite) and a quartz-bearing syenite (laminated silica-oversaturated syenite, LSO, with scarce corroded plagioclase plus diopside + biotite ± hornblende + ilmenite ± magnetite + titanite + apatite). Both types share a remarkable enrichment in incompatible elements as K, Ba, Sr, P and LREE. Apatite saturation temperatures of ~ 1060-1090 °C are the best estimates of liquidus, whereas the pressure of emplacement, based on Al-in-hornblende barometry, is estimated as 3.3 to 4.8 kbar. Although both units crystallized under oxidizing conditions, oxygen fugacity was probably higher in LSS, as shown by higher mg# of the mafic minerals and higher hematite contents in Hem-Ilmss. In contrast with the Ca-bearing alkali-feldspar from LSO, which hosts most of the whole-rock Sr and Pb, virtually Ca-free alkali-feldspar from LSS hosts ~ 50% of whole-rock Sr and ~ 80% of Pb, the remainder of these elements being shared by apatite, pyroxene and titanite. This contrast reflects a strong crystal-chemical control, whereby a higher proportion of an element with similar ratio and charge (Ca2 +) enhances the residence of Sr and Pb in the M-site of alkali feldspar. The more alkaline character of the LSS magma is inferred to have inhibited zircon saturation; Zr + Hf remained in solution until late in the crystallization, and were mostly accommodated in the structure of Ca-Na pyroxene and titanite, which are one order of magnitude richer in these elements compared to the

  2. Mineralization of the vertebral bodies in Atlantic salmon (Salmo salar L.) is initiated segmentally in the form of hydroxyapatite crystal accretions in the notochord sheath

    PubMed Central

    Wang, Shou; Kryvi, Harald; Grotmol, Sindre; Wargelius, Anna; Krossøy, Christel; Epple, Mattias; Neues, Frank; Furmanek, Tomasz; Totland, Geir K

    2013-01-01

    We performed a sequential morphological and molecular biological study of the development of the vertebral bodies in Atlantic salmon (Salmo salar L.). Mineralization starts in separate bony elements which fuse to form complete segmental rings within the notochord sheath. The nucleation and growth of hydroxyapatite crystals in both the lamellar type II collagen matrix of the notochord sheath and the lamellar type I collagen matrix derived from the sclerotome, were highly similar. In both matrices the hydroxyapatite crystals nucleate and accrete on the surface of the collagen fibrils rather than inside the fibrils, a process that may be controlled by a template imposed by the collagen fibrils. Apatite crystal growth starts with the formation of small plate-like structures, about 5 nm thick, that gradually grow and aggregate to form extensive multi-branched crystal arborizations, resembling dendritic growth. The hydroxyapatite crystals are always oriented parallel to the long axis of the collagen fibrils, and the lamellar collagen matrices provide oriented support for crystal growth. We demonstrate here for the first time by means of synchroton radiation based on X-ray diffraction that the chordacentra contain hydroxyapatite. We employed quantitative real-time PCR to study the expression of key signalling molecule transcripts expressed in the cellular core of the notochord. The results indicate that the notochord not only produces and maintains the notochord sheath but also expresses factors known to regulate skeletogenesis: sonic hedgehog (shh), indian hedgehog homolog b (ihhb), parathyroid hormone 1 receptor (pth1r) and transforming growth factor beta 1 (tgfb1). In conclusion, our study provides evidence for the process of vertebral body development in teleost fishes, which is initially orchestrated by the notochord. PMID:23711083

  3. Crystal preferred orientations of minerals from mantle xenoliths in alkali basaltic rocks form the Catalan Volcanic Zone (NE Spain)

    NASA Astrophysics Data System (ADS)

    Fernández-Roig, Mercè; Galán, Gumer; Mariani, Elisabetta

    2015-04-01

    Mantle xenoliths in alkali basaltic rocks from the Catalan Volcanic Zone, associated with the Neogene-Quaternary rift system in NE Spain, are formed of anhydrous spinel lherzolites and harzburgites with minor olivine websterites. Both peridotites are considered residues of variable degrees of partial melting, later affected by metasomatism, especially the harzburgites. These and the websterites display protogranular microstructures, whereas lherzolites show continuous variation between protogranular, porphyroclastic and equigranular forms. Thermometric data of new xenoliths indicate that protogranular harzburgites, lherzolites and websterites were equilibrated at higher temperatures than porphyroclastic and equigranular lherzolites. Mineral chemistry also indicates lower equilibrium pressure for porphyroclastic and equigranular lherzolites than for the protogranular ones. Crystal preferred orientations (CPOs) of olivine and pyroxenes from these new xenoliths were determined with the EBSD-SEM technique to identify the deformation stages affecting the lithospheric mantle in this zone and to assess the relationships between the deformation fabrics, processes and microstructures. Olivine CPOs in protogranular harzburgites, lherzolites and a pyroxenite display [010]-fiber patterns characterized by a strong point concentration of the [010] axis normal to the foliation and girdle distribution of [100] and [001] axes within the foliation plane. Olivine CPO symmetry in porphyroclastic and equigranular lherzolites varies continuously from [010]-fiber to orthorhombic and [100]-fiber types. The orthorhombic patterns are characterized by scattered maxima of the three axes, which are normal between them. The rare [100]-fiber patterns display strong point concentration of [100] axis, with normal girdle distribution of the other two axes, which are aligned with each other. The patterns of pyroxene CPOs are more dispersed than those of olivine, especially for clinopyroxene, but

  4. The crystal structure and crystal chemistry of fernandinite and corvusite

    USGS Publications Warehouse

    Evans, H.T.; Post, J.E.; Ross, D.R.; Nelen, J.A.

    1994-01-01

    Using type material of fernandinite from Minasragra, Peru, and corvusite from the Jack Claim, La Sal Mountains, Utah, the properties and crystal chemistry of these minerals have been determined by Rietveld analysis of the powder X-ray-diffraction patterns. The crystal structure of both species is isotypic with the V2O5 -type layer first found for ??-Ag0.68V2O5; it consists of chains of VO6 octahedra linked by opposite corners (parallel to b) condensed by edge-sharing to form the layer. The vanadium has average valence 4.8, and the resulting layer-charge is balanced by varying amounts of Ca, Na, and K in the interlayer region accompanied by labile water. This study has confirmed the validity of fernandinite as a unique mineral species. It is closely related to corvusite, from which it is distinguished on the basis of the dominant interlayer cation: Ca for fernandinite, Na for curvusite. -Authors

  5. The Conterminous United States Mineral-Resource Assessment Program; background information to accompany folios of geologic and mineral-resource maps of the Harrison 1 degree x 2 degrees quadrangle, Missouri and Arkansas, and the Joplin 1 degree x 2 degrees quadrangle Kansas and Missouri

    USGS Publications Warehouse

    Pratt, Walden P.

    1997-01-01

    The Harrison 1 deg X 2 deg quadrangle in southwestern Missouri and northwestern Arkansas and the Joplin 1 deg X 2 deg quadrangle in southeastern Kansas and southwestern Missouri were studied under the Conterminous United States Mineral-Resource Assessment Program (CUSMAP). Map publications in the CUSMAP folios included bedrock geology, subsurface geochemistry, geophysics, subsurface stratigraphy and lithofacies, and potential resources of metallic and industrial minerals and coal. This report summarizes the contents of those publications and related studies.

  6. Phlogopite- and clinopyroxene-dominated fractional crystallization of an alkaline primitive melt: petrology and mineral chemistry of the Dariv Igneous Complex, Western Mongolia

    NASA Astrophysics Data System (ADS)

    Bucholz, Claire E.; Jagoutz, Oliver; Schmidt, Max W.; Sambuu, Oyungerel

    2014-04-01

    We present field relationships, petrography, and mineral major and trace element data for the Neoproterozoic Dariv Igneous Complex of the Altaids of Western Mongolia. This unique complex of high-K plutonic rocks is composed of well-exposed, km-scale igneous intrusions of wehrlites, phlogopite wehrlites, apatite-bearing phlogopite clinopyroxenites, monzogabbros, monzodiorites, and clinopyroxene-bearing monzonites, all of which are intruded by late stage lamprophyric and aplitic dikes. The biotite-dominated igneous complex intrudes depleted harzburgitic serpentinite. The observed lithological variability and petrographic observations suggest that the plutonic rocks can be ascribed to a fractionation sequence defined by olivine + clinopyroxene ± Fe-Ti oxides → phlogopite + apatite → K-feldspar + plagioclase → amphibole + quartz. Notably, phlogopite is the dominant hydrous mafic mineral. Petrogenesis of the observed lithologies through a common fractionation sequence is supported by a gradual decrease in the Mg# [molar Mg/(Fetotal + Mg) × 100] of mafic minerals. Crystallization conditions are derived from experimental phase petrology and mineral chemistry. The most primitive ultramafic cumulates crystallized at ≤0.5 GPa and 1,210-1,100 °C and oxygen fugacity ( fO2) of +2-3 ∆FMQ (log units above the fayalite-quartz-magnetite buffer). Trace element modeling using clinopyroxene and apatite rare earth element compositions indicates that the dominant mechanism of differentiation was fractional crystallization. The trace element composition of a parental melt was calculated from primitive clinopyroxene compositions and compares favorably with the compositions of syn-magmatic lamprophyres that crosscut the fractionation sequence. The parental melt composition is highly enriched in Th, U, large ion lithophile elements, and light rare earth elements and has a pronounced negative Nb-Ta depletion, suggestive of an alkaline primitive melt originating from a subduction

  7. The SHAND quaternary system for evaluating the supersilicic or subsilicic crystal-chemistry of eclogite minerals, and potential new UHPM pyroxene and garnet end-members

    NASA Astrophysics Data System (ADS)

    Smith, D. C.

    2006-09-01

    The stoichiometry of pyroxenes {viiiX2+ viY2+ ivZ4+ 2 O6} and garnets {xiiX2+ 3 viY3+ 2 ivZ4+ 3 O12} is re-evaluated by a theoretical crystal-chemical approach that takes into account natural phenomena that do not fit with conventional anhydrous stoichiometric mineralogy: the existence in eclogites of microinclusions of other minerals that may have been exsolved from previous supersilicic or subsilicic UHPM pyroxene or garnet. Different definitions of supersilicic and subsilicic are discussed and the one based on the ability to exsolve SiO2 and leave behind a stoichiometric pyroxene or garnet is recommended for general adoption. The SHAND system (S = Si et al.; H = H; A = Al et al.; N = Na et al.; D = divalents) for projecting multivariate chemical space involving 23 cations and 104 selected natural or potential mineral species on to two essential diagrams (SAND and SHND) is described in full for the first time. Numerous possible chemical exchanges are considered and justified with respect to known mineral phenomena such as cation vacancies, octahedral silicon or protonation. Several new potential end-members are presented, in particular “supersilipyx”, “supersiligar” and “subsiligar”. It is suggested that small quantities of these end-members can be incorporated into UHPM solid-solutions and lead to various exsolution phenomena during eclogite exhumation.

  8. 30 CFR 250.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 250.226 Section 250.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Zone Management Act (CZMA) information must accompany the EP? The following CZMA information...

  9. 30 CFR 250.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 250.245 Section 250.245 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Documents (docd) § 250.245 What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?...

  10. A discussion of isotopic systematics and mineral zoning in the shergottites - Evidence for a 180 m.y. igneous crystallization age

    NASA Technical Reports Server (NTRS)

    Jones, J. H.

    1986-01-01

    The chronologies of the Shergotty, Zagami, ALHA 77005, and EETA 79001 meteorites were reexamined on the basis of shergottites' petrography and mineral chemistry data. Among the various isochrons, the concordant Rb-Sr (about 180 Myr) and U-Th-Pb (about 190 Myr) internal isochrons are interpreted as representing the time of igneous crystallization, while the Rb-Sr, Sm-Nd, and Pb-Pb whole-rock isochrons are interpreted as mixing lines, and are reasonably attributed to igneous processes such as wall-rock assimilation and magma mixing. If the approximated age of less than 200 Myr is correct, the shergottites represent the youngest known extraterrestrial basalts. This conclusion supports the hypothesis that the SNC meteorites are samples of Mars.

  11. Steklite, KAl(SO4)2: A finding at the Tolbachik Volcano, Kamchatka, Russia, validating its status as a mineral species and crystal structure

    NASA Astrophysics Data System (ADS)

    Murashko, M. N.; Pekov, I. V.; Krivovichev, S. V.; Chernyatyeva, A. P.; Yapaskurt, V. O.; Zadov, A. E.; Zelensky, M. E.

    2013-12-01

    Steklite KAl(SO4)2 has been found in sublimates of the Yadovitaya (Poisonous) fumarole at the second cinder cone of the northern breach of the Great Fissure Tolbachik Eruption, Tolbachik volcano, Kamchatka Peninsula, Russia. Steklite was approved as a valid mineral species by the Commission on New Minerals, Nomenclature, and Mineral Classification of the International Mineralogical Association on June 2, 2011 (IMA no. 2011-041). The name steklite is left for this mineral, as it was named by Chesnokov et al. (1995) for its technogenic analog from a burnt dump of coal mine no. 47 at Kopeisk, the Southern Urals, Russia. It is named after the Russian word steklo, meaning glass, in allusion to the visual similarity of its lamellae to thin glass platelets. At Tolbachik, steklite is associated with alumoklyuchevskite, langbeinite, euchlorine, fedotovite, chalcocyanite, hematite, and lyonsite. It occurs as hexagonal or irregular-shaped lamellar crystals with the major form {001} reaching 30 μm in thickness and 0.2 mm (occasionally up to 1 mm) in width. The crystals are frequently split. They are combined into openwork aggregates or thin crusts up to 1.5 × 2.5 cm in area. Steklite is transparent and colorless, with vitreous luster. The cleavage is perfect, parallel to (001). The mineral is brittle. The Mohs' hardness is 2.5. D calc is 2.797 g/cm3. Steklite is optically uniaxial, (-), ω = 1.546(2), ɛ = 1.533(3). The chemical composition (wt %, electron-microprobe data) is as follows: 0.09 Na2O, 18.12 K2O, 0.08 CaO, 0.03 MnO, 2.02 Fe2O3, 18.18 Al2O3, 61.80 SO3. The total is 100.37. The empirical formula calculated on the basis of eight O atoms is: (K0.997Na0.008Ca0.004)Σ1.009(Al0.925Fe{0.066/3+}Mg0.003Mn0.001)Σ0.995S2.01O8. Steklite is trigonal, space group P321, a = 4.7281(3), c = 7.9936(5) Å, V = 154.76(17)Å3, Z =1. The strongest reflections in the X-ray powder diffraction pattern ( d, Å- I[ hkl]) are: 8.02-34[001], 4.085-11[100], 3.649-100[011, 101], 2

  12. Influence of organic ligands on the crystal growth of magnesite (MgCO3) : Mechanistic aspects and implications for the mineral sequestration of CO2

    NASA Astrophysics Data System (ADS)

    Gautier, Q.; Jordan, G.; Bénézeth, P.; Schott, J.

    2010-12-01

    The efficiency of Mg-silicates mineral carbonation processes is limited by the slow dissolution of silicate minerals and subsequent formation of a stable Mg-carbonate phase. It is therefore necessary to enhance the whole process to make it economically and energetically viable. It has recently been suggested that organic ligands, whose ability to significantly enhance the rate of dissolution of silicate minerals is well known, could be used in this purpose (Park et al., 2003). Studies on calcite have shown that most organic ligands have an inhibitory effect on its crystal growth (e.g Reddy & Hoch, 2001). However, their effect has not yet been assessed on Mg-carbonates precipitation, and might be different due to the highly hydrated state of the Mg2+ ion in aqueous solution. We will present results of magnesite crystal growth experiments performed in mixed-flow reactors (MFR) as well as under an Hydrothermal Atomic Force Microscope (HAFM). Three different types of ligands have been chosen for their different chemical properties and chelating effect: Oxalate, Citrate and EDTA. Experiments have been performed at temperatures between 80 and 120°C, alkaline pH, and dissolved CO2 concentration ~ 0.02 mol/L. Chemical speciation was calculated for all experiments, thus allowing to monitor saturation states and to determine magnesite growth rates as a function of solution chemistry. MFR experiments results show that the addition of variable amounts of Oxalate to the solutions leads to a limited decrease of the precipitation rate (up to ~30% decrease with 10-2 M Oxalate). Nonetheless, another set of experiments, performed at constant Oxalate concentration and changing saturation state, revealed an increase of the kinetic constant of magnesite precipitation. Furthermore, HAFM experiments, performed at constant saturation states with Oxalate, Citrate and EDTA, showed an increase of the kinetic constant of the magnesite step advancement rate, which is positively correlated to

  13. 30 CFR 250.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 250.226 Section 250.226 Mineral Resources MINERALS MANAGEMENT SERVICE... and Information Contents of Exploration Plans (ep) § 250.226 What Coastal Zone Management Act...

  14. 30 CFR 250.255 - What decommissioning information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What decommissioning information must accompany the DPP or DOCD? 250.255 Section 250.255 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... Information Contents of Development and Production Plans (dpp) and Development Operations...

  15. 30 CFR 250.254 - What mitigation measures information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What mitigation measures information must accompany the DPP or DOCD? 250.254 Section 250.254 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Information Contents of Development and Production Plans (dpp) and Development Operations...

  16. 30 CFR 250.253 - What lease stipulations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What lease stipulations information must accompany the DPP or DOCD? 250.253 Section 250.253 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Information Contents of Development and Production Plans (dpp) and Development Operations...

  17. 30 CFR 250.262 - What administrative information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What administrative information must accompany the DPP or DOCD? 250.262 Section 250.262 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... Information Contents of Development and Production Plans (dpp) and Development Operations...

  18. A new mineral species ferricoronadite, Pb[Mn6 4+(Fe3+, Mn3+)2]O16: mineralogical characterization, crystal chemistry and physical properties

    NASA Astrophysics Data System (ADS)

    Chukanov, Nikita V.; Aksenov, Sergey M.; Jančev, Simeon; Pekov, Igor V.; Göttlicher, Jörg; Polekhovsky, Yury S.; Rusakov, Vyacheslav S.; Nelyubina, Yuliya V.; Van, Konstantin V.

    2016-07-01

    A new mineral ferricoronadite with the simplified formula Pb(Mn6 4+Fe2 3+)O16 was discovered in the orogenetic zone related to the "Mixed Series" metamorphic complex near the Nežilovo village, Pelagonian massif, Republic of Macedonia. Associated minerals are franklinite, gahnite, hetaerolite, roméite, almeidaite, Mn-analogue of plumboferrite, zincohögbomite analogue with Fe3+ > Al, zincochromite, Zn-bearing talc, Zn-bearing muscovite, baryte, quartz and zircon. Ferricoronadite is a late hydrothermal mineral forming veinlets up to 8 mm thick in granular aggregate predominantly composed by zinc-dominant spinels. The new mineral is opaque, black, with brownish black streak. The luster is strong submetallic to metallic. The micro-indentation hardness is 819 kg/mm2. Distinct cleavage is observed on (100). Ferricoronadite is brittle, with uneven fracture. The density calculated from the empirical formula is 5.538 g/cm3. In reflected light, ferricoronadite is light gray. The reflectance values [ R max/ R min, % ( λ, nm)] are: 28.7/27.8 (470), 27.6/26.6 (546), 27.2/26.1 (589), 26.5/25.5 (650). The IR spectrum shows the absence of H2O and OH groups. According to the Mössbauer spectrum, all iron is trivalent. The Mn K-edge XANES spectroscopy shows that Mn is predominantly tetravalent, with subordinate Mn3+. The chemical composition is (wt%; electron microprobe, Mn apportioned between MnO2 and Mn2O3 based on the charge-balance requirement): BaO 5.16, PbO 24.50, ZnO 0.33, Al2O3 0.50, Mn2O3 9.90, Fe2O3 11.45, TiO2 4.19, MnO2 44.81, total 100.84. The empirical formula based on 8 cations Mn + Fe + Ti + Al + Zn pfu is Pb1.03Ba0.32(Mn 4.85 4+ Fe 1.35 3+ Mn 1.18 3+ Ti0.49Al0.09Zn0.04)Σ8.00O16. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is tetragonal, space group I4/ m, a = 9.9043(7), c = 2.8986(9) Å, V = 284.34(9) Å3, Z = 1. In ferricoronadite, double chains of edge-sharing (Mn, Fe, Ti)-centered octahedra are connected

  19. Crystallization in organo-mineral micro-domains in the crossed-lamellar layer of Nerita undata (Gastropoda, Neritopsina).

    PubMed

    Nouet, Julius; Baronnet, Alain; Howard, Lauren

    2012-02-01

    Crossed-lamellar shell microstructure consists of a sophisticated arrangement of interspersed lamellae, which is very commonly found in Gastropoda or Bivalvia shell layers. Its smallest constitutive microstructural units are usually described as sub-micrometric fibers, or rods, and form very ordered and regular patterns. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) imaging confirms the presence of even smaller building units in the form of organo-mineral granules, and we further investigate their internal structure within aragonite crossed-lamellar internal layer of Nerita undata (Gastropoda, Neritopsina) shell. Their coalescence may have controlled anisotropically the propagation of the crystallographic coherence through this complex microstructure, as suggested by the propagation of the microtwinning pattern between neighboring granules.

  20. Structural characterization of the N-terminal mineral modification domains from the molluscan crystal-modulating biomineralization proteins, AP7 and AP24.

    PubMed

    Wustman, Brandon A; Morse, Daniel E; Evans, John Spencer

    2004-08-05

    The AP7 and AP24 proteins represent a class of mineral-interaction polypeptides that are found in the aragonite-containing nacre layer of mollusk shell (H. rufescens). These proteins have been shown to preferentially interfere with calcium carbonate mineral growth in vitro. It is believed that both proteins play an important role in aragonite polymorph selection in the mollusk shell. Previously, we demonstrated the 1-30 amino acid (AA) N-terminal sequences of AP7 and AP24 represent mineral interaction/modification domains in both proteins, as evidenced by their ability to frustrate calcium carbonate crystal growth at step edge regions. In this present report, using free N-terminal, C(alpha)-amide "capped" synthetic polypeptides representing the 1-30 AA regions of AP7 (AP7-1 polypeptide) and AP24 (AP24-1 polypeptide) and NMR spectroscopy, we confirm that both N-terminal sequences possess putative Ca (II) interaction polyanionic sequence regions (2 x -DD- in AP7-1, -DDDED- in AP24-1) that are random coil-like in structure. However, with regard to the remaining sequences regions, each polypeptide features unique structural differences. AP7-1 possesses an extended beta-strand or polyproline type II-like structure within the A11-M10, S12-V13, and S28-I27 sequence regions, with the remaining sequence regions adopting a random-coil-like structure, a trait common to other polyelectrolyte mineral-associated polypeptide sequences. Conversely, AP24-1 possesses random coil-like structure within A1-S9 and Q14-N16 sequence regions, and evidence for turn-like, bend, or loop conformation within the G10-N13, Q17-N24, and M29-F30 sequence regions, similar to the structures identified within the putative elastomeric proteins Lustrin A and sea urchin spicule matrix proteins. The similarities and differences in AP7 and AP24 N-terminal domain structure are discussed with regard to joint AP7-AP24 protein modification of calcium carbonate growth.

  1. Fluid-rock interaction controlling clay-mineral crystallization in quartz-rich rocks and its influence on the seismicity of the Carboneras fault area (SE Spain)

    NASA Astrophysics Data System (ADS)

    Jimenez-Espinosa, R.; Abad, I.; Jimenez-Millan, J.; Lorite-Herrera, M.

    2009-04-01

    The Carboneras Fault zone is one of the longest fault in the Betic Cordillera (SE Spain) and it would be a good candidate to generate large magnitude earthquakes (Gracia et al., 2006). Seismicity in the region is characterised by low to moderate magnitude events, although large destructive earthquakes have occurred, which reveals significant earthquake and tsunami hazards (Masana et al., 2004). Due to the internal architecture of the fault zone, shear lenses of post-orogenic sediments of Miocene and Pliocene age including marls and sandstones sequences are juxtaposed to the predominant slaty gouges of the Alpine basement. Microcataclasites and gouges of the quartz-rich post-orogenic sediments are also developed as cm- to m-scale bands, allowing the comparison between the deformed materials and their protoliths. Red, yellow and white sandstones and their respective cataclasites can be identified. This communication is concerned with the clay mineral crystallization events in these materials and its possible influence on the seismicity model of the region. The presence of phyllosilicates in fault zones as either neoformed or inherited clays is commonly related with fluid circulation and a mechanically weak fault behaviour (e.g., Wang, 1984). A critical factor for the understanding of the mechanical role of clays in fault rocks is to determine the timing of formation of mineral assemblages and microstructure of fault rocks and protolith. The effects of post-faulting alteration limit inferences about fault behaviour that can be made from exhumed rocks. The Carboneras fault zone provides good opportunities to study mineral processes enhanced by deformation, given that it is located in a region of arid climate and shows outcroppings of quartzitic rocks included in slaty rocks. Combined XRD, optical microscopy and SEM analyses reveal that deformed quartzitic rocks are enriched in phyllosilicates, increasing especially the amount of chlorite. The samples strongly damaged

  2. Crystal-structure refinement of zirconium-rich eudialyte and its place among calcium-poor eudialyte-group minerals

    SciTech Connect

    Aksenov, S. M. Rastsvetaeva, R. K.

    2013-09-15

    The repeated refinement of the crystal structure of zirconium-rich eudialyte based on the X-ray diffraction data set collected earlier revealed new structural features. The trigonal unit-cell parameters are a = 14.222(3) A, c = 30.165(5) A, V = 5283.9 A{sup 3}. The refinement resulted in the reduction of the R factor from 0.045 (2347F > 4{sigma}(F)) to 0.035 (3124F > 3{sigma}(F)). It was found that the ordering of Ca and Fe in six-membered rings leads to the lowering of the symmetry to R3. An excess amount of zirconium (more than three atoms per symmetrically independent unit) is located in the M2 microregion in square and five-vertex polyhedral positions. However, this amount is insufficient to be dominant, and the deficiency of zirconium is compensated for by sodium atoms. Based on the new data, zirconium-rich eudialyte can be assigned to the oneillite subtype, being a zirconium-rich and aluminum variety of raslakite.

  3. Analyzing the Deposition of Titanium Dioxide Nanoparticles at Model Rough Mineral Surfaces Using a Quartz Crystal Microbalance with Dissipation Monitoring

    NASA Astrophysics Data System (ADS)

    Li, Y.; Kananizadeh, N.; Rodenhausen, K. B.; Schubert, M.; Bartelt-Hunt, S.

    2015-12-01

    Titanium dioxide nanoparticles (nTiO2) is the most extensively manufactured engineered materials. nTiO2 from sunscreens was found to enter sediments after released into a lake. nTiO2 may also enter the subsurface via irrigation using effluents from wastewater treatment plants. Interaction of nTiO2 with soils and sediments will largely influence their fate, transport, and ecotoxicity. Measuring the interaction between nTiO2 and natural substrates (e.g. such as sands) is particularly challenging due to highly heterogeneous and rough natural sand surfaces. In this study, an engineered controllable rough surface known as three dimensional nanostructured sculptured columnar thin films (SCTFs) has been used to mimic surface roughness. SCTFs were fabricated by glancing angle deposition (GLAD), a physical vapor deposition technique facilitated by electron beam evaporation. Interaction between nTiO2 and SCTF coated surfaces was investigated using a quartz crystal microbalance with dissipation monitoring (QCM-D). In parallel, a Generalized Ellipsometry (GE) was coupled with the QCM-D to measure the deposition of nTiO2. We found that the typical QCM-D modeling approach, e.g. viscoelastic model, would largely overestimate the mass of deposited nTiO2, because the frequency drops due to particle deposition or water entrapment in rough areas were not differentiated. Here, we demonstrate a new approach to model QCM-D data for nTiO2 deposition on rough surfaces, which couples the viscoelastic model with a model of flow on the non-uniform surface.

  4. Single crystal structure investigations under high-pressure of the mineral cordierite with an improved high-pressure cell

    NASA Astrophysics Data System (ADS)

    Koepke, J.; Schulz, H.

    1986-05-01

    An improved single-crystal high-pressure anvil cell with beryllium-gaskets was used for the investigations of structure and lattice parameters of cordierite which had been heated in an Ar stream at about 1,000° C to remove natural water from its structural channels. The influences of pressure transmitting media were studied by using water as a pressure medium at pressures of 0.3, 0.9, 1.2, and 2.3 GPa and fluorcarbon, a liquid consisting of large molecules, at 2.2 GPa. Water, but not fluorcarbon, is able to enter the channels in the cordierite structure. Large variations in the lattice constants resulted from changing the pressure medium used. A previously supposed discontinuity of the b lattice constant at nearly 0.3 GPa could not be established by the measurements taken so that there is no evidence for a phase transition at this pressure. Possibly the observed tilting of two tetrahedra against each other in this structure could have led to this misinterpretion. When water, but not fluorcarbon, is used as a pressure medium at 2.3 GPa, an additional electron density peak, presumably a water oxygen atom, appears in the channels. The water prevents the channels from shrinking and fixes their width at a value comparable to that of a naturally hydrated cordierite. In one of the silicate-tetrahedra the Si-O bond lengths are compressed almost 1 percent (2.3 GPa). This process may initiate a phase transition at higher pressures.

  5. 30 CFR 550.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 550.245 Section 550.245 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.245 What hydrogen sulfide (H2S) information must accompany the DPP or...

  6. 30 CFR 550.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 550.245 Section 550.245 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.245 What hydrogen sulfide (H2S) information must accompany the DPP or...

  7. 30 CFR 550.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 550.245 Section 550.245 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.245 What hydrogen sulfide (H2S) information must accompany the DPP or...

  8. Comment on "Evaluation of X-ray diffraction methods for determining the crystal growth mechanisms of clay minerals in mudstones, shales and slates," by L. N. Warr and D. R. Peacor

    USGS Publications Warehouse

    Eberl, D.D.; Srodon, J.; Drits, V.A.

    2003-01-01

    A recent paper by Warr and Peacor (2002) suggested that our use of the Bertaut-Warren-Averbach technique (MudMaster computer program) for studying changes in crystallite thickness distributions (CTDs) of clay minerals during diagenesis and very low-grade metamorphism is not reliable because it is dependent on many variables which can not be fully controlled. Furthermore, the authors implied that the measured shapes of CTDs cannot be used with confidence to deduce crystal growth mechanisms and histories for clays, based on our CTD simulation approach (using the Galoper computer program). We disagree with both points, and show that the techniques are powerful, reliable and useful for studying clay mineral alteration in rocks. ?? 2003 Schweiz. Mineral. Petrogr. Ges.

  9. 25 CFR 215.15 - Leases to be accompanied by Form D.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Leases to be accompanied by Form D. 215.15 Section 215.15 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.15 Leases to be accompanied by Form D. Lead and zinc leases...

  10. [Wernicke encephalopathy accompanying linitis plastica].

    PubMed

    Soós, Zsuzsanna; Salamon, Mónika; Oláh, Roland; Czégeni, Anna; Salamon, Ferenc; Folyovich, András; Winkler, Gábor

    2014-01-05

    Wernicke encephalopathy (or Wernicke-Korsakoff encephalopathy) is a rarely diagnosed neurological disorder, which is caused by vitamin B1 deficiency. In the classical form it is characterized by a typical triad (confusion, oculomotor disturbance and ataxia), however, in the majority of the cases only confusion is present. It can be frequently observed in subjects with chronic alcohol consumption, but it may accompany different pathological states of which end stage malignant diseases are the most importants, where confusion may have different backgrounds. The authors present the case of an old male patient with advanced gastric cancer recognised and treated vitamin B1 deficiency, and they draw attention to difficulties of the diagnosis of Wernicke's disease.

  11. 30 CFR 550.215 - What hydrogen sulfide (H2S) information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What hydrogen sulfide (H2S) information must accompany the EP? 550.215 Section 550.215 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... Information Contents of Exploration Plans (ep) § 550.215 What hydrogen sulfide (H2S) information...

  12. 30 CFR 550.215 - What hydrogen sulfide (H2S) information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What hydrogen sulfide (H2S) information must accompany the EP? 550.215 Section 550.215 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... Information Contents of Exploration Plans (ep) § 550.215 What hydrogen sulfide (H2S) information...

  13. 30 CFR 250.215 - What hydrogen sulfide (H2S) information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What hydrogen sulfide (H2S) information must accompany the EP? 250.215 Section 250.215 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION... CONTINENTAL SHELF Plans and Information Contents of Exploration Plans (ep) § 250.215 What hydrogen...

  14. 30 CFR 550.215 - What hydrogen sulfide (H2S) information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What hydrogen sulfide (H2S) information must accompany the EP? 550.215 Section 550.215 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... Information Contents of Exploration Plans (ep) § 550.215 What hydrogen sulfide (H2S) information...

  15. 30 CFR 550.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 550.226 Section 550.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Contents of Exploration Plans (ep) § 550.226 What Coastal Zone Management Act...

  16. 30 CFR 550.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 550.226 Section 550.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Contents of Exploration Plans (ep) § 550.226 What Coastal Zone Management Act...

  17. 30 CFR 550.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 550.226 Section 550.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Contents of Exploration Plans (ep) § 550.226 What Coastal Zone Management Act...

  18. 30 CFR 550.255 - What decommissioning information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What decommissioning information must accompany the DPP or DOCD? 550.255 Section 550.255 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... brief description of how you intend to decommission your wells, platforms, pipelines, and...

  19. 30 CFR 550.255 - What decommissioning information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What decommissioning information must accompany the DPP or DOCD? 550.255 Section 550.255 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... brief description of how you intend to decommission your wells, platforms, pipelines, and...

  20. 30 CFR 550.255 - What decommissioning information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What decommissioning information must accompany the DPP or DOCD? 550.255 Section 550.255 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... brief description of how you intend to decommission your wells, platforms, pipelines, and...

  1. 30 CFR 550.222 - What lease stipulations information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What lease stipulations information must accompany the EP? 550.222 Section 550.222 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... Information Contents of Exploration Plans (ep) § 550.222 What lease stipulations information must...

  2. 30 CFR 550.222 - What lease stipulations information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What lease stipulations information must accompany the EP? 550.222 Section 550.222 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... Information Contents of Exploration Plans (ep) § 550.222 What lease stipulations information must...

  3. Electron microprobe mineral analysis guide

    NASA Technical Reports Server (NTRS)

    Brown, R. W.

    1980-01-01

    Electron microprobe mineral analysis guide is a compilation of X-ray tables and spectra recorded from various mineral matrices. Spectra were obtained using electron microprobe, equipped with LiF geared, curved crystal X-ray spectrometers, utilizing typical analytical operating conditions: 15 Kv acceleration potential, 0.02 microampere sample current as measured on a clinopyroxene standard (CP19). Tables and spectra are presented for the majority of elements, fluorine through uranium, occurring in mineral samples from lunar, meteoritic and terrestrial sources. Tables for each element contain relevant analytical information, i.e., analyzing crystal, X-ray peak, background and relative intensity information, X-ray interferences and a section containing notes on the measurement. Originally intended to cover silicates and oxide minerals the tables and spectra have been expanded to cover other mineral phases. Electron microprobe mineral analysis guide is intended as a spectral base to which additional spectra can be added as the analyst encounters new mineral matrices.

  4. 30 CFR 250.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 250.260 Section 250.260 Mineral Resources MINERALS MANAGEMENT... Operations Coordination Documents (docd) § 250.260 What Coastal Zone Management Act (CZMA) information...

  5. 30 CFR 250.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What biological, physical, and socioeconomic information must accompany the DPP or DOCD? 250.247 Section 250.247 Mineral Resources MINERALS MANAGEMENT... SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

  6. 30 CFR 250.225 - What information on the onshore support facilities you will use must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What information on the onshore support facilities you will use must accompany the EP? 250.225 Section 250.225 Mineral Resources MINERALS MANAGEMENT... SHELF Plans and Information Contents of Exploration Plans (ep) § 250.225 What information on the...

  7. 30 CFR 250.256 - What related facilities and operations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What related facilities and operations information must accompany the DPP or DOCD? 250.256 Section 250.256 Mineral Resources MINERALS MANAGEMENT... SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

  8. Elastic properties of minerals

    SciTech Connect

    Aleksandrov, K.S.; Prodaivoda, G.T.

    1993-09-01

    Investigations of the elastic properties of the main rock-forming minerals were begun by T.V. Ryzhova and K.S. Aleksandrov over 30 years ago on the initiative of B.P. Belikov. At the time, information on the elasticity of single crystals in general, and especially of minerals, was very scanty. In the surveys of that time there was information on the elasticity of 20 or 30 minerals. These, as a rule, did not include the main rock-forming minerals; silicates were represented only by garnets, quartz, topaz, tourmaline, zircon, beryl, and staurolite, which are often found in nature in the form of large and fairly high-quality crystals. Then and even much later it was still necessary to prove a supposition which now seems obvious: The elastic properties of rocks, and hence the velocities of elastic (seismic) waves in the earth`s crust, are primarily determined by the elastic characteristics of the minerals composing these rocks. Proof of this assertion, with rare exceptions of mono-mineralic rocks (marble, quartzite, etc.) cannot be obtained without information on the elasticities of a sufficiently large number of minerals, primarily framework, layer, and chain silicates which constitute the basis of most rocks. This also served as the starting point and main problem of the undertakings of Aleksandrov, Ryzhova, and Belikov - systematic investigations of the elastic properties of minerals and then of various rocks. 108 refs., 7 tabs.

  9. Integrated single crystal laser ablation U/Pb and (U-Th)/He dating of detrital accessory minerals - Proof-of-concept studies of titanites and zircons from the Fish Canyon tuff

    NASA Astrophysics Data System (ADS)

    Horne, Alexandra M.; van Soest, Matthijs C.; Hodges, Kip V.; Tripathy-Lang, Alka; Hourigan, Jeremy K.

    2016-04-01

    Excimer laser technologies enable a rapid and effective approach to simultaneous U/Pb geochronology and (U-Th)/He thermochronology of a wide range of detrital accessory minerals. Here we describe the 'laser ablation double dating' (LADD) method and demonstrate its viability by applying it to zircon and titanite crystals from the well-characterized Fish Canyon tuff. We found that LADD dates for Fish Canyon zircon (206Pb/238U - 28.63 ± 0.11 Ma; (U-Th)/He - 28.38 ± 0.73 Ma) are statistically indistinguishable from those obtained through established, traditional methods of single-crystal dating. The same is true for Fish Canyon titanite LADD dates: 206Pb/238U - 28.08 ± 0.90 Ma; (U-Th)/He - 27.98 ± 0.86 Ma. As anticipated, given that LADD involves the analysis of smaller amounts of material than traditional methods, it yields dates with higher analytical uncertainty. However, this does not substantially reduce the utility of the results for most applications to detrital datasets. An important characteristic of LADD is that it encourages the chemical characterization of crystals by backscattered electron, cathodoluminescence, and/or Raman mapping prior to dating. In addition, by permitting the rapid and robust dating of crystals regardless of the degree of their abrasion during sedimentary transport, the method theoretically should yield dates that are more broadly representative of those of the entire population of detrital crystals in a natural sample.

  10. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  11. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  12. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 2 2014-04-01 2014-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  13. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  14. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  15. An assessment of calcite crystal growth mechanisms based on crystal size distributions

    USGS Publications Warehouse

    Kile, D.E.; Eberl, D.D.; Hoch, A.R.; Reddy, M.M.

    2000-01-01

    Calcite crystal growth experiments were undertaken to test a recently proposed model that relates crystal growth mechanisms to the shapes of crystal size distributions (CSDs). According to this approach, CSDs for minerals have three basic shapes: (1) asymptotic, which is related to a crystal growth mechanism having constant-rate nucleation accompanied by surface-controlled growth; (2) lognormal, which results from decaying-rate nucleation accompanied by surface-controlled growth; and (3) a theoretical, universal, steady-state curve attributed to Ostwald ripening. In addition, there is a fourth crystal growth mechanism that does not have a specific CSD shape, but which preserves the relative shapes of previously formed CSDs. This mechanism is attributed to supply-controlled growth. All three shapes were produced experimentally in the calcite growth experiments by modifying nucleation conditions and solution concentrations. The asymptotic CSD formed when additional reactants were added stepwise to the surface of solutions that were supersaturated with respect to calcite (initial Ω = 20, where Ω = 1 represents saturation), thereby leading to the continuous nucleation and growth of calcite crystals. Lognormal CSDs resulted when reactants were added continuously below the solution surface, via a submerged tube, to similarly supersaturated solutions (initial Ω = 22 to 41), thereby leading to a single nucleation event followed by surface-controlled growth. The Ostwald CSD resulted when concentrated reactants were rapidly mixed, leading initially to high levels of supersaturation (Ω >100), and to the formation and subsequent dissolution of very small nuclei, thereby yielding CSDs having small crystal size variances. The three CSD shapes likely were produced early in the crystallization process, in the nanometer crystal size range, and preserved during subsequent growth. Preservation of the relative shapes of the CSDs indicates that a supply-controlled growth mechanism

  16. Crystal chemical effects on the partitioning of trace elements between mineral and melt - An experimental study of melilite with applications to refractory inclusions from carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Beckett, John R.; Spivack, Arthur J.; Hutcheon, Ian D.; Wasserburg, G. J.; Stolper, Edward M.

    1990-01-01

    Results are presented on the partitioning experiments for trace elements Be, Sc, Ba, La, Ce, and Tm between melilite and melt for a bulk composition relevant to Type B inclusions, using a technique, described by Brody and Flemings (1966), by which distributon coeffecients can be obtained over the entire range of crystallization from trace element analysis of a single zoned crystal. Zoned crystals of melilite were grown during controlled cooling rate experiments, and trace element concentrations were determined by SIMS. At each step in the crystal growth, trace element concentrations in the coexisting melt were determined by mass balance, using stepwise integration of a Rayleigh fractionation equation.

  17. Protein Crystallization

    NASA Technical Reports Server (NTRS)

    Chernov, Alexander A.

    2005-01-01

    Nucleation, growth and perfection of protein crystals will be overviewed along with crystal mechanical properties. The knowledge is based on experiments using optical and force crystals behave similar to inorganic crystals, though with a difference in orders of magnitude in growing parameters. For example, the low incorporation rate of large biomolecules requires up to 100 times larger supersaturation to grow protein, rather than inorganic crystals. Nucleation is often poorly reproducible, partly because of turbulence accompanying the mixing of precipitant with protein solution. Light scattering reveals fluctuations of molecular cluster size, its growth, surface energies and increased clustering as protein ages. Growth most often occurs layer-by-layer resulting in faceted crystals. New molecular layer on crystal face is terminated by a step where molecular incorporation occurs. Quantitative data on the incorporation rate will be discussed. Rounded crystals with molecularly disordered interfaces will be explained. Defects in crystals compromise the x-ray diffraction resolution crucially needed to find the 3D atomic structure of biomolecules. The defects are immobile so that birth defects stay forever. All lattice defects known for inorganics are revealed in protein crystals. Contribution of molecular conformations to lattice disorder is important, but not studied. This contribution may be enhanced by stress field from other defects. Homologous impurities (e.g., dimers, acetylated molecules) are trapped more willingly by a growing crystal than foreign protein impurities. The trapped impurities induce internal stress eliminated in crystals exceeding a critical size (part of mni for ferritin, lysozyme). Lesser impurities are trapped from stagnant, as compared to the flowing, solution. Freezing may induce much more defects unless quickly amorphysizing intracrystalline water.

  18. Crystal chemical constraints on inter-mineral Fe isotope fractionation and implications for Fe isotope disequilibrium in San Carlos mantle xenoliths

    NASA Astrophysics Data System (ADS)

    Macris, Catherine A.; Manning, Craig E.; Young, Edward D.

    2015-04-01

    The origin of variations in iron isotope compositions of mantle minerals is uncertain, and predictions of equilibrium inter-mineral iron isotope fractionation conflict. This hinders interpretation of the petrologic and geochemical implications of Fe isotope data from mantle lithologies. To address this, we present a revised ionic model for predicting equilibrium iron isotope fractionation between mantle minerals and use it to interpret measured inter-mineral iron isotopic fractionation from five distinct mantle xenolith lithologies from San Carlos, Arizona. The samples represent a broad range of modal abundances and include lherzolite, harzburgite, dunite, clinopyroxenite, and websterite. The xenoliths exhibit Fe-isotopic variation between minerals in a single sample, and between samples. In all cases where spinel and olivine coexist, the 57Fe/54Fe of spinel is greater than that of the corresponding olivine, agreeing with expectations for equilibrium fractionation from theory (ionic model), but disagreeing with predictions based on Mössbauer data. The 57Fe/54Fe values of clinopyroxenes from the xenoliths show no clear systematic differences. We interpret this to be a result of varying degrees of metasomatism, perhaps involving interaction with a melt. The spinel peridotite samples (lherzolite, harzburgite, and dunite) are partially melted residual mantle that exhibit a decrease in whole-rock 57Fe/54Fe with increasing olivine abundance. This is consistent with progressive extraction of a 57Fe-rich partial melt. The clinopyroxenite has the highest whole-rock 57Fe/54Fe, consistent with its origin as a cumulate from an unrelated magma possessing elevated 57Fe/54Fe. The websterite sample is transitional to Group II type xenoliths, has the lowest whole-rock 57Fe/54Fe of the investigated samples, and likely experienced a more complex metasomatic history. This study demonstrates that the Fe isotope compositions of San Carlos xenoliths and their component minerals record

  19. Mineral oils

    NASA Technical Reports Server (NTRS)

    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.

  20. The VLab repository of thermodynamics and thermoelastic properties of minerals

    NASA Astrophysics Data System (ADS)

    Da Silveira, P. R.; Sarkar, K.; Wentzcovitch, R. M.; Shukla, G.; Lindemann, W.; Wu, Z.

    2015-12-01

    Thermodynamics and thermoelastic properties of minerals at planetary interior conditions are essential as input for geodynamics simulations and for interpretation of seismic tomography models. Precise experimental determination of these properties at such extreme conditions is very challenging. Therefore, ab initio calculations play an essential role in this context, but at the cost of great computational effort and memory use. Setting up a widely accessible and versatile mineral physics database can relax unnecessary repetition of such computationally intensive calculations. Access to such data facilitates transactional interaction across fields and can advance more quickly insights about deep Earth processes. Hosted by the Minnesota Supercomputing Institute, the Virtual Laboratory for Earth and Planetary Materials (VLab) was designed to develop and promote the theory of planetary materials using distributed, high-throughput quantum calculations. VLab hosts an interactive database of thermodynamics and thermoelastic properties or minerals computed by ab initio. Such properties can be obtained according to user's preference. The database is accompanied by interactive visualization tools, allowing users to repeat and build upon previously published results. Using VLab2015, we have evaluated thermoelastic properties, such as elastic coefficients (Cij), Voigt, Reuss, and Voigt-Reuss-Hill aggregate averages for bulk (K) and shear modulus (G), shear wave velocity (VS), longitudinal wave velocity (Vp), and bulk sound velocity (V0) for several important minerals. Developed web services are general and can be used for crystals of any symmetry. Results can be tabulated, plotted, or downloaded from the VLab website according to user's preference.

  1. Dual mineralization of dicalcium phosphate and hydroxyapatite formation on both sides of porous membrane: Alternating current induces pH-modulated crystal deposition

    NASA Astrophysics Data System (ADS)

    Watanabe, Junji; Akashi, Mitsuru

    2009-09-01

    Dual mineralization on a porous membrane was carried out using an electrochemical approach. The porous membrane was interposed between a pair of glass cells, and calcium chloride (CaCl 2) and sodium hydrogenphosphate (Na 2HPO 4) solutions were separately injected into the cells. After inserting platinum electrodes into the cells, an alternating current with a sine waveform was applied for a given period of time. The resulting membrane was removed from the glass cells and rinsed with ultrapure water. The minerals formed on the membrane were analyzed by using spectroscopic methods such as scanning electron microscopy (SEM), infrared (IR) spectroscopy, and X-ray diffraction (XRD) and identified to be dicalcium phosphate and hydroxyapatite. It was noted that dicalcium phosphate formed on one side of the membrane, while hydroxyapatite was formed on the other side. Thus, dual mineralization could be successfully achieved on both sides of the porous membrane under an alternating current. This process of dual mineralization is very useful for the formation of versatile organic-inorganic hybrids and also for the regulation of the polymorphs on either side of a membrane.

  2. 30 CFR 250.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 250.245 Section 250.245 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Development Operations Coordination Documents (docd) § 250.245 What hydrogen sulfide (H2S) information...

  3. 30 CFR 550.225 - What information on the onshore support facilities you will use must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What information on the onshore support facilities you will use must accompany the EP? 550.225 Section 550.225 Mineral Resources BUREAU OF OCEAN... wastes not specifically addressed in the relevant National Pollution Discharge Elimination System...

  4. 30 CFR 550.225 - What information on the onshore support facilities you will use must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What information on the onshore support facilities you will use must accompany the EP? 550.225 Section 550.225 Mineral Resources BUREAU OF OCEAN... wastes not specifically addressed in the relevant National Pollution Discharge Elimination System...

  5. 30 CFR 250.225 - What information on the onshore support facilities you will use must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What information on the onshore support facilities you will use must accompany the EP? 250.225 Section 250.225 Mineral Resources BUREAU OF OCEAN.... Unusual wastes are those wastes not specifically addressed in the relevant National Pollution...

  6. 30 CFR 550.225 - What information on the onshore support facilities you will use must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What information on the onshore support facilities you will use must accompany the EP? 550.225 Section 550.225 Mineral Resources BUREAU OF OCEAN... wastes not specifically addressed in the relevant National Pollution Discharge Elimination System...

  7. 30 CFR 550.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Operations Coordination Documents (docd) § 550.260 What Coastal Zone Management Act (CZMA) information must... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 550.260 Section 550.260 Mineral Resources BUREAU OF OCEAN...

  8. 30 CFR 250.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 250.260 Section 250.260 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND...

  9. 30 CFR 550.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Operations Coordination Documents (docd) § 550.260 What Coastal Zone Management Act (CZMA) information must... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 550.260 Section 550.260 Mineral Resources BUREAU OF OCEAN...

  10. 30 CFR 550.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Operations Coordination Documents (docd) § 550.260 What Coastal Zone Management Act (CZMA) information must... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 550.260 Section 550.260 Mineral Resources BUREAU OF OCEAN...

  11. 30 CFR 250.224 - What information on support vessels, offshore vehicles, and aircraft you will use must accompany...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What information on support vessels, offshore... information on support vessels, offshore vehicles, and aircraft you will use must accompany the EP?...

  12. Mineral Carbonation Employing Ultramafic Mine Waste

    NASA Astrophysics Data System (ADS)

    Southam, G.; McCutcheon, J.; Power, I. M.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.

    2014-12-01

    Carbonate minerals are an important, stable carbon sink being investigated as a strategy to sequester CO2 produced by human activity. A natural playa (Atlin, BC, CAN) that has demonstrated the ability to microbially-accelerate hydromagnesite formation was used as an experimental model. Growth of microbial mats from Atlin, in a 10 m long flow-through bioreactor catalysed hydromagnesite precipitation under 'natural' conditions. To enhance mineral carbonation, chrysotile from the Clinton Creek Asbestos Mine (YT, CAN) was used as a target substrate for sulphuric acid leaching, releasing as much as 94% of the magnesium into solution via chemical weathering. This magnesium-rich 'feedstock' was used to examine the ability of the microbialites to enhance carbonate mineral precipitation using only atmospheric CO2 as the carbon source. The phototrophic consortium catalysed the precipitation of platy hydromagnesite [Mg5(CO3)4(OH)2·4H2O] accompanied by magnesite [MgCO3], aragonite [CaCO3], and minor dypingite [Mg5(CO3)4(OH)2·5H2O]. Scanning Electron Microscopy-Energy Dispersive Spectroscopy indicated that cell exteriors and extracellular polymeric substances (EPS) served as nucleation sites for carbonate precipitation. In many cases, entire cyanobacteria filaments were entombed in magnesium carbonate coatings, which appeared to contain a framework of EPS. Cell coatings were composed of small crystals, which intuitively resulted from rapid crystal nucleation. Excess nutrient addition generated eutrophic conditions in the bioreactor, resulting in the growth of a pellicle that sealed the bioreactor contents from the atmosphere. The resulting anaerobic conditions induced fermentation and subsequent acid generation, which in turn caused a drop in pH to circumneutral values and a reduction in carbonate precipitation. Monitoring of the water chemistry conditions indicated that a high pH (> 9.4), and relatively high concentrations of magnesium (> 3000 ppm), compared with the natural

  13. Biomineralization: mineral formation by organisms

    NASA Astrophysics Data System (ADS)

    Addadi, Lia; Weiner, Steve

    2014-09-01

    Organisms form many different types of minerals, with diverse shapes and sizes. These minerals fulfill a variety of functions. Inspired by the late H A Lowenstam, Steve Weiner and Lia Addadi have addressed many questions that relate to the mechanisms by which biological organisms produce these mineral phases and how their structures relate to their functions. Addadi and Weiner have explored the manner in which macromolecules extracted from mineralized tissues can interact with some crystal planes and not others, how these macromolecules can be occluded inside the forming crystals residing preferentially on specific crystal planes, and how they can induce one polymorph of calcium carbonate and not another to nucleate. Addadi and Weiner have also identified a novel strategy used by the sea urchin to form its smooth and convoluted mineralized skeletal elements. The strategy involves the initial production by cells of a highly disordered mineral precursor phase in vesicles, and then the export of this so-called amorphous phase to the site of skeletal formation, where it crystallizes. This strategy is now known to be used by many different invertebrate phyla, as well as by vertebrates to build bones and teeth. One of the major current research aims of the Weiner--Addadi group is to understand the biomineralization pathways whereby ions are extracted from the environment, are transported and deposited inside cells within vesicles, how these disordered phases are then transferred to the site of skeletal formation, and finally how the so-called amorphous phase crystallizes. Biology has clearly evolved unique strategies for forming crystalline minerals. Despite more than 300 years of research in this field, many challenging questions still remain unanswered.

  14. Crystallization Pathways in Biomineralization

    NASA Astrophysics Data System (ADS)

    Weiner, Steve; Addadi, Lia

    2011-08-01

    A crystallization pathway describes the movement of ions from their source to the final product. Cells are intimately involved in biological crystallization pathways. In many pathways the cells utilize a unique strategy: They temporarily concentrate ions in intracellular membrane-bound vesicles in the form of a highly disordered solid phase. This phase is then transported to the final mineralization site, where it is destabilized and crystallizes. We present four case studies, each of which demonstrates specific aspects of biological crystallization pathways: seawater uptake by foraminifera, calcite spicule formation by sea urchin larvae, goethite formation in the teeth of limpets, and guanine crystal formation in fish skin and spider cuticles. Three representative crystallization pathways are described, and aspects of the different stages of crystallization are discussed. An in-depth understanding of these complex processes can lead to new ideas for synthetic crystallization processes of interest to materials science.

  15. Volcanic facies and mineral chemistry of Tertiary volcanics in the northern part of the Eastern Pontides, northeast Turkey: implications for pre-eruptive crystallization conditions and magma chamber processes

    NASA Astrophysics Data System (ADS)

    Yücel, Cem; Arslan, Mehmet; Temizel, İrfan; Abdioğlu, Emel

    2014-06-01

    Tertiary volcanics in the northern zone of the Eastern Pontides are characterized by subaerial and shallow-subaqueous facieses, and are divided into three volcanic suites: Eocene aged (1) basalt-trachybasalt-basaltic trachyandesite (BTB) and (2) trachyte-trachyandesite (TT), and Miocene aged (3) basanite-tephrite (BT) suites. Clinopyroxene is a common phase in all three volcanic suites, and has different compositions with Mg# varying from 0.57 to 0.91 in BTB suite and 0.57-0.84 in TT suite to 0.65-0.90 in BT suite. Feldspars in all suites generally exhibit wide range of compositions from sanidine to albite or anorthite and have weak normal and reverse compositional zoning. Olivines in BTB and BT suites have Fo60-92. Hornblendes in BTB, TT and BT suites are commonly magnesio-hastingsite and rare pargasite in composition (Mg#: 0.67-0.90). Brown mica is mainly phlogopite with Mg# ranging from 0.56 to 0.92 in the BTB suite, 0.59-0.84 in the TT suite, and 0.75-0.93 in the BT suite. Analcime is present only in the BT suite rocks. Fe-Ti oxides in all suites are mainly composed of magnetite and titanomagnetite. Textural petrographic and mineral chemical data suggest that magmas had undergone hydrous and anhydrous crystallizations in deep-, mid-, and shallow-crustal magma chambers. Clinopyroxene thermobarometric calculations show that Eocene magma chambers were characterized by temperature ranging from 1,100 to 1,244 °C and pressure ranging from 1.84 to 5.39 kbar. Similarly, the Miocene magma chambers were characterized by temperature ranging from 1,119 to 1,146 °C and pressure ranging from 4.23 to 4.93 kbar. Hornblende thermobarometry, oxygen fugacity, and hygrometer reveal that the crystallization temperature of Eocene volcanics range from 956 to 959 °C at pressure ranging from 6.49 to 6.52 kbar. Eocene volcanics were characterized by water content ranging from 7.83 to 8.57 wt.% and oxygen fugacity of 10-9.36 to 10-9.46 (ΔNNO+2). Miocene volcanics had crystallization

  16. Mineral resource of the month: Vermiculite

    USGS Publications Warehouse

    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.

  17. Clay Minerals

    SciTech Connect

    Mueller, Karl T.; Sanders, Rebecca L.; Washton, Nancy M.

    2014-03-14

    Clay minerals are important components of the environment and are involved or implicated in processes such as the uptake of pollutants and the release of nutrients and as potential platforms for a number of chemical reactions. Owing to their small particle sizes (typically, on the order of microns or smaller) and mixing with a variety of other minerals and soil components, advanced characterization methods are needed to study their structures, dynamics, and reactivities. In this article, we describe the use of solid-state NMR methods to characterize the structures and chemistries of clay minerals. Early one-pulse magic-angle spinning (MAS) NMR studies of 27Al and 29Si have now been enhanced and extended with new studies utilizing advanced methodologies (such as Multiple Quantum MAS) as well as studies of less-sensitive nuclei. In additional work, the issue of reactivity of clay minerals has been addressed, including studies of reactive surface area in the environment. Utilizations of NMR-sensitive nuclides within the clay minerals themselves, and in molecules that react with specific sites on the clay mineral surfaces, have aided in understanding the reactivity of these complex aluminosilicate systems.

  18. Redgillite, Cu[subscript 6](OH)1 0(SO[subscript 4]).2H[subscript 2]O, a new mineral from Caldbeck Fells, Cumbria, England, UK: Description and crystal structure

    SciTech Connect

    Pluth, J.J.; Steele, I.M.; Kampf, A.R.; Green, D.I.

    2008-10-03

    Redgillite, Cu{sub 6}(OH){sub 10}(SO{sub 4}) {center_dot} H{sub 2}O, space group P2{sub 1}/c, a 3.155(3) {angstrom}, b 10.441(8) {angstrom}, c 19.436(16) {angstrom}, {beta} 90.089(13){sup o}, V = 640.2(9) {angstrom}{sup 3}, Z = 2, is a new mineral from Silver Gill, Caldbeck Fells, Cumbria, England. The strongest six lines of the X-ray powder-diffraction pattern [d in {angstrom}, (I) (hkl)] are: 9.72 (90) (002), 7.11 (100) (012), 4.60 (30) (022), 4.068 (20) (023), 2.880 (30) (112,11{bar 2}), 2.318 (50) (131,13{bar 1}). It occurs as translucent to transparent grass-green bladed crystals up to 0.15 mm long with squared-off or tapering terminations; usually in radiating groups. Forms observed are {l_brace}001{r_brace} prominent, {l_brace}010{r_brace} as composite stepped faces, and {l_brace}100{r_brace} irregular. Redgillite has white streak, vitreous lustre and Mohs hardness of {approx}2. Blades are slightly flexible with irregular fracture and exhibit a perfect {l_brace}001{r_brace} cleavage and good {l_brace}100{r_brace} and {l_brace}010{r_brace} cleavages. The measured density (by sink-float) is 3.45(5) g/cm{sup 3}; the calculated density is 3.450 g/cm{sup 3}. The mineral dissolves slowly in dilute HCl. Redgillite is biaxial-negative with {alpha} = 1.693(2), {beta} = 1.721(2), {gamma} = 1.723(2), 2V = 30(2){sup o} (meas.) and 30{sup o} (calc.); dispersion is r > v, medium; pleochroism: Y blue-green > X blue-green > Z yellow-green; orientation: X c, Y = b, Z a. Electron microprobe analyses yielded CuO 68.9, SO{sub 3} 11.6, total 80.5. With water inferred from the structure analysis, the empirical formula is: Cu{sub 5.995}(OH){sub 9.991}(SO{sub 4}){sub 1.003} {center_dot} H{sub 2}O. Redgillite is typically found in thin fractures in partly oxidized sulphides where it is commonly associated with langite and more rarely with malachite, cuprite, connellite and brochantite. The name is for the Red Gill mine, from which the mineral is best known. The crystal structure of

  19. Metastatic Basal cell carcinoma accompanying gorlin syndrome.

    PubMed

    Bilir, Yeliz; Gokce, Erkan; Ozturk, Banu; Deresoy, Faik Alev; Yuksekkaya, Ruken; Yaman, Emel

    2014-01-01

    Gorlin-Goltz syndrome or basal cell nevus syndrome is an autosomal dominant syndrome characterized by skeletal anomalies, numerous cysts observed in the jaw, and multiple basal cell carcinoma of the skin, which may be accompanied by falx cerebri calcification. Basal cell carcinoma is the most commonly skin tumor with slow clinical course and low metastatic potential. Its concomitance with Gorlin syndrome, resulting from a mutation in a tumor suppressor gene, may substantially change morbidity and mortality. A 66-year-old male patient with a history of recurrent basal cell carcinoma was presented with exophthalmus in the left eye and the lesions localized in the left lateral orbita and left zygomatic area. His physical examination revealed hearing loss, gapped teeth, highly arched palate, and frontal prominence. Left orbital mass, cystic masses at frontal and ethmoidal sinuses, and multiple pulmonary nodules were detected at CT scans. Basal cell carcinoma was diagnosed from biopsy of ethmoid sinus. Based on the clinical and typical radiological characteristics (falx cerebri calcification, bifid costa, and odontogenic cysts), the patient was diagnosed with metastatic skin basal cell carcinoma accompanied by Gorlin syndrome. Our case is a basal cell carcinoma with aggressive course accompanying a rarely seen syndrome.

  20. Spatial distribution and compositional variation of APS minerals related to uranium deposits in the Kiggavik-Andrew Lake structural trend, Nunavut, Canada

    NASA Astrophysics Data System (ADS)

    Riegler, Thomas; Quirt, Dave; Beaufort, Daniel

    2016-02-01

    The Kiggavik-Andrew Lake structural trend consists of four mineralized zones, partially outcropping, lying 2 km south of the erosional contact with the unmetamorphosed sandstone and basal conglomerates of the Paleoproterozoic Thelon Formation. The mineralization is controlled by a major E-W fault system associated with illite and sudoite alteration halos developed in the Archean metagraywackes of the Woodburn Lake Group. Aluminum phosphate sulfate (APS) minerals from the alunite group crystallized in association with the clay minerals in the basement alteration halo as well as in the overlying sandstones, which underwent mostly diagenesis. APS minerals are Sr- and S-rich (svanbergite end-member) in the sedimentary cover overlying the unconformity, whereas they are light rare earth elements (LREE)-rich (florencite end-member) in the altered basement rocks below the unconformity. The geochemical signature of each group of APS minerals together with the petrography indicates three distinct generations of APS minerals related to the following: (1) paleoweathering of continental surfaces prior to the basin occurrence, (2) diagenetic processes during the burial history of the lower unit of the Thelon sandstones, and (3) hydrothermal alteration processes which accompanied the uranium deposition in the basement rocks and partially overlap the sedimentary-diagenetic mineral parageneses. In addition, the association of a first generation of APS minerals with both detrital cerium oxide and aluminum oxy-hydroxide highlights the fact that a part of the detrital material of the basal Thelon Formation originated from eroded paleolaterite (allochthonous regolith). The primary rare earth element (REE)-bearing minerals (e.g., monazite, REE carbonates, and allanite) of the host rocks were characterized to identify the potential sources of REE. The REE chemical composition highlights a local re-incorporation of the REE released from the alteration processes in the APS minerals of

  1. Nevadaite, (Cu2+, Al, V3+)6 [Al8 (PO4)8 F8] (OH 2 (H2O)22, a new phosphate mineral species from the Gold Quarry mine, Carlin, Eureka County, Nevada: description and crystal structure

    USGS Publications Warehouse

    Cooper, M.A.; Hawthorne, F.C.; Roberts, Andrew C.; Foord, E.E.; Erd, Richard C.; Evans, H.T.; Jensen, M.C.

    2004-01-01

    Nevadaite, (Cu2+, ???, Al, V3+)6 (PO4)8 F8 (OH)2 (H2O)22, is a new supergene mineral species from the Gold Quarry mine, near Carlin, Eureka County, Nevada, U.S.A. Nevadaite forms radiating clusters to 1 mm of prismatic crystals, locally covering surfaces more that 2 cm across; individual crystals are elongate on [001] with a length:width ratio of > 10:1 and a maximum diameter of ???30 ??m. It also occurs as spherules and druses associated with colorless to purple-black fluellite, colorless wavellite, strengitevariscite, acicular maroon-to-red hewettite, and rare anatase, kazakhstanite, tinticite, leucophosphite, torbernite and tyuyamunite. Nevadaite is pale green to turquoise blue with a pale powder-blue streak and a vitreous luster; it does not fluoresce under ultra-violet light. It has no cleavage, a Mohs hardness of ???3, is brittle with a conchoidal fracture, and has measured and calculated densities of 2.54 and 2.55 g/cm3, respectively. Nevadaite is biaxial negative, with ?? 1.540, ?? 1.548, ?? 1.553, 2V(obs.) = 76??, 2V(calc.) = 76??, pleochroic with X pale greenish blue, Y very pale greenish blue, Z blue, and with absorption Z ??? X > Y and orientation X = c, Y = a, Z = b. Nevadaite is orthorhombic, space group P21mn, a 12.123(2), b 18.999(2), c 4.961(1) A?? , V 1142.8(2) A??3, Z = 1, a:b:c = 0.6391:1:0.2611. The strongest seven lines in the X-ray powder-diffraction pattern [d in A??(I)(hkl)] are: 6.077(10)(200), 5.618(9)(130), 9.535(8)(020), 2.983(6)(241), 3.430(4)(041), 2.661(4)(061 , and 1.844(4)(352). A chemical analysis with an electron microprobe gave P2O5 32.54, Al2O3 27.07, V2O3 4.24, Fe2O3 0.07, CuO 9.24, ZnO 0.11, F 9.22, H2O (calc.) 23.48, OH ??? F -3.88, sum 102.09 wt.%; the valence states of V and Fe, and the amount of H2O, were determined by crystal-structure analysis. The resulting empirical formula on the basis of 63.65 anions (including 21.65 H2O pfu) is (CU2+2.00 Zn0.02 V3+0.98 Fe3+0.01 Al1.15)??4.16 Al8 P7.90 O32 [F8.37 (OH 1.63]??10 (H2O

  2. Industrial Minerals

    ERIC Educational Resources Information Center

    Bradbury, James C.

    1978-01-01

    The past year is seen as not particularly good for industrial minerals and for industry in general. Environmental concerns continued to trouble the industry with unacceptable asbestos concentrations and chlorofluorocarbon effects on ozone. A halting U.S. economy also affected industrial progress. (MA)

  3. Hanawaltite, Hg1+6Hg2+[Cl,(OH)]2O3 - A new mineral from the Clear Creek claim, San Benito County, California: Description and crystal structure

    USGS Publications Warehouse

    Roberts, Andrew C.; Grice, Joel D.; Gault, Robert A.; Criddle, A.J.; Erd, Richard C.

    1996-01-01

    Hanawaltite, ideally Hg1+6Hg2+O3Cl2, is orthorhombic, Pbma (57), with unit-cell parameters refined from powder data: a=11.790(3), b=13.881(4), c=6.450(2) A??, V=1055.7(6) A??3, a:b:c =0.8494:1:0.4647, Z=4. The strongest six lines of the X-ray powder-diffraction pattern [d in A?? (I)(hkl)] are: 5.25 (80)(111), 3.164 (60)(231), 3.053 (100)(041), 2.954 (70)(141), 2.681 (50)(401), and 2.411 (50)(232,341). The mineral is an extremely rare constituent in a small prospect pit near the long-abandoned Clear Creek mercury mine, New Idria district, San Benito County, California. It was found on a single-fracture surface where it is intimately associated with calomel, native mercury, cinnabar, montroydite, and quartz. Individual crystals are subhedral to anhedral, platy to somewhat bladed, and average about 50 ??m in longest dimension. The largest known crystal is approximately 0.3??0.3 mm in size and is striated parallel [001]. Hanawaltite is opaque to translucent (on very thin edges), black to very dark brown-black in color, with a black to dark red-brown streak. Other physical properties include: metallic luster; cleavage {001} good; uneven fracture; brittle; nonfluorescent; H<5; calculated density (for the empirical formula) 9.51 g/cm3. In polished section, hanawaltite is moderately to strongly bireflectant and is pleochroic white (R1) to blue-white (R2). In reflected plane-polarized light, it is white with orange-red internal reflections in very thin grains and at grain margins. The anisotropy is strong with bright metallic blue rotation tints. Measured reflectance values, in air and in oil, are tabulated. Electron-microprobe analysis yielded Hg2O 82.46, HgO 14.27, Cl 3.33, H2O [0.34], sum [100.40], less O=Cl 0.75, total [99.65] wt. %, corresponding to Hg1+6.00H2+1.00[Cl 1.43(OH)0.57]??2.00O3.00, based on O+C1=5. After the crystal structure was determined, the original microprobe value for Hg2O, 96.2, was partitioned in a ratio of 6Hg2O:HgO and (OH) was calculated, such

  4. The Use of Backscattered Electron Imaging and Transmission Electron Microscopy to Assess Bone Architecture and Mineral Loci: Effect of Intermittent Slow-Release Sodium Fluoride Therapy

    NASA Astrophysics Data System (ADS)

    Zerwekh, Joseph E.; Bellotto, Dennis; Prostak, Kenneth S.; Hagler, Herbert K.; Pak, Charles Y. C.

    1996-04-01

    Backscattered electron imaging (BEI) and transmission electron microscopy (TEM) were used to examine the effects of treatment with intermittent slow-release sodium fluoride (SRNaF) and continuous calcium citrate on bone architecture and crystallinity. Examination was performed in nondecalcified biopsies obtained from patients following up to four years of therapy (placebo or SRNaF) and compared to pretreatment biopsies from each patient, as well as to bone from young, normal subjects. BEI images disclosed increased areas of recent bone formation following fluoride administration. There was no evidence of a mineralization defect in any biopsy and both cortical and trabecular architecture remained normal. TEM analysis demonstrated intrafibrillar platelike crystals and extrafibrillar needlelike crystals for both the pre- and post-treatment biopsies as well as for the bone from young normal subjects. There was no evidence of increased crystal size or of an increase in extrafibrillar mineral deposition. These observations suggest that intermittent SRNaF and continuous calcium therapy exerts an anabolic action on the skeleton not accompanied by a mineralization defect or an alteration of bone mineral deposition. The use of BEI and TEM holds promise for the study of the pathophysiology and treatment of metabolic bone diseases.

  5. Mineral bioprocessing

    SciTech Connect

    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.

  6. Crystallization from Gels

    NASA Astrophysics Data System (ADS)

    Narayana Kalkura, S.; Natarajan, Subramanian

    Among the various crystallization techniques, crystallization in gels has found wide applications in the fields of biomineralization and macromolecular crystallization in addition to crystallizing materials having nonlinear optical, ferroelectric, ferromagnetic, and other properties. Furthermore, by using this method it is possible to grow single crystals with very high perfection that are difficult to grow by other techniques. The gel method of crystallization provides an ideal technique to study crystal deposition diseases, which could lead to better understanding of their etiology. This chapter focuses on crystallization in gels of compounds that are responsible for crystal deposition diseases. The introduction is followed by a description of the various gels used, the mechanism of gelling, and the fascinating phenomenon of Liesegang ring formation, along with various gel growth techniques. The importance and scope of study on crystal deposition diseases and the need for crystal growth experiments using gel media are stressed. The various crystal deposition diseases, viz. (1) urolithiasis, (2) gout or arthritis, (3) cholelithiasis and atherosclerosis, and (4) pancreatitis and details regarding the constituents of the crystal deposits responsible for the pathological mineralization are discussed. Brief accounts of the theories of the formation of urinary stones and gallstones and the role of trace elements in urinary stone formation are also given. The crystallization in gels of (1) the urinary stone constituents, viz. calcium oxalate, calcium phosphates, uric acid, cystine, etc., (2) the constituents of the gallstones, viz. cholesterol, calcium carbonate, etc., (3) the major constituent of the pancreatic calculi, viz., calcium carbonate, and (4) cholic acid, a steroidal hormone are presented. The effect of various organic and inorganic ions, trace elements, and extracts from cereals, herbs, and fruits on the crystallization of major urinary stone and gallstone

  7. The ACOSTA accompanying measure A2106.

    PubMed

    Thayer, C; De Moor, G; Van Goor, J

    1994-10-01

    At a time when the informatics and telecommunications industries are looking for new markets to exploit in relation, for example, to the emerging ISDN and broadband communications networks, there is a need to create a broad consensus in Europe by bringing together systematically the relevant industries including telecom service providers, health care providers, insurance organisations, standardisation experts and policy makers. The aim of the ACOSTA (Consensus Formation and Standardisation Promotion) Accompanying Measure is the creation of more general awareness of the relevant environment among all the parties, better specification of common requirements and options taking better account of the real needs of the users, and enlargement of the common market in health care telematics.

  8. The Mechanism of Atomization Accompanying Solid Injection

    NASA Technical Reports Server (NTRS)

    Castleman, R A , Jr

    1933-01-01

    A brief historical and descriptive account of solid injection is followed by a detailed review of the available theoretical and experimental data that seem to throw light on the mechanism of this form of atomization. It is concluded that this evidence indicates that (1) the atomization accompanying solid injection occurs at the surface of the liquid after it issues as a solid stream from the orifice; and (2) that such atomization has a mechanism physically identical with the atomization which takes place in an air stream, both being due merely to the formation, at the gas-liquid interface, of fine ligaments under the influence of the relative motion of gas and liquid, and to their collapse, under the influence of surface tension, to form the drops in the spray.

  9. Sacral Perineural Cyst Accompanying Disc Herniation

    PubMed Central

    Ju, Chang Il; Shin, Ho; Kim, Hyeun Sung

    2009-01-01

    Although most of sacral perineural cysts are asymptomatic, some may produce symptoms. Specific radicular pain may be due to distortion, compression, or stretching of nerve root by a space occupying cyst. We report a rare case of S1 radiculopathy caused by sacral perineural cyst accompanying disc herniation. The patient underwent a microscopic discectomy at L5-S1 level. However, the patient's symptoms did not improved. The hypesthesia persisted, as did the right leg pain. Cyst-subarachnoid shunt was set to decompress nerve root and to equalize the cerebrospinal fluid pressure between the cephalad thecal sac and cyst. Immediately after surgery, the patient had no leg pain. After 6 months, the patient still remained free of leg pain. PMID:19352483

  10. MicroRNA 224 Regulates Ion Transporter Expression in Ameloblasts To Coordinate Enamel Mineralization

    PubMed Central

    Fan, Yi; Zhou, Yachuan; Zhou, Xuedong; Sun, Feifei; Gao, Bo; Wan, Mian; Zhou, Xin; Sun, Jianxun; Xu, Xin; Cheng, Lei; Crane, Janet

    2015-01-01

    Enamel mineralization is accompanied by the release of protons into the extracellular matrix, which is buffered to regulate the pH value in the local microenvironment. The present study aimed to investigate the role of microRNA 224 (miR-224) as a regulator of SLC4A4 and CFTR, encoding the key buffering ion transporters, in modulating enamel mineralization. miR-224 was significantly downregulated as ameloblasts differentiated, in parallel with upregulation of SLC4A4 and CFTR. Overexpression of miR-224 downregulated SLC4A4 and CFTR expression in cultured human epithelial cells. A microRNA luciferase assay confirmed the specific binding of miR-224 to the 3′ untranslated regions (UTRs) of SLC4A4 and CFTR mRNAs, thereby inhibiting protein translation. miR-224 agomir injection in mouse neonatal incisors resulted in normal enamel length and thickness, but with disturbed organization of the prism structure and deficient crystal growth. Moreover, the enamel Ca/P ratio and microhardness were markedly reduced after miR-224 agomir administration. These results demonstrate that miR-224 plays a pivotal role in fine tuning enamel mineralization by modulating SLC4A4 and CFTR to maintain pH homeostasis and support enamel mineralization. PMID:26055330

  11. Mineral induction by immobilized phosphoproteins

    NASA Technical Reports Server (NTRS)

    Saito, T.; Arsenault, A. L.; Yamauchi, M.; Kuboki, Y.; Crenshaw, M. A.

    1997-01-01

    Dentin phosphoproteins are thought to have a primary role in the deposition of mineral on the collagen of dentin. In this study we determined the type of binding between collagen and phosphoproteins necessary for mineral formation onto collagen fibrils and whether the phosphate esters are required. Bovine dentin phosphophoryn or phosvitin from egg yolk were immobilized on reconstituted skin type I collagen fibrils by adsorption or by covalent cross-linking. In some samples the ester phosphate was removed from the covalently cross-linked phosphoproteins by treatment with acid phosphatase. All samples were incubated at 37 degrees C in metastable solutions that do not spontaneously precipitate. Reconstituted collagen fibrils alone did not induce mineral formation. The phosphoproteins adsorbed to the collagen fibrils desorbed when the mineralization medium was added, and mineral was not induced. The mineral induced by the cross-linked phosphoproteins was apatite, and the crystals were confined to the surface of the collagen fibrils. With decreasing medium saturation the time required for mineral induction increased. The interfacial tensions calculated for apatite formation by either phosphoprotein cross-linked to collagen were about the same as that for phosphatidic acid liposomes and hydroxyapatite. This similarity in values indicates that the nucleation potential of these highly phosphorylated surfaces is about the same. It is concluded that phosphoproteins must be irreversibly bound to collagen fibrils for the mineralization of the collagen network in solutions that do not spontaneously precipitate. The phosphate esters of phosphoproteins are required for mineral induction, and the carboxylate groups are not sufficient.

  12. Tin-carrier minerals in metaluminous granites of the western Nanling Range (southern China): Constraints on processes of tin mineralization in oxidized granites

    NASA Astrophysics Data System (ADS)

    Wang, Ru Cheng; Xie, Lei; Chen, Jun; Yu, Apeng; Wang, Lubin; Lu, Jianjun; Zhu, Jinchu

    2013-09-01

    Huashan, Guposhan and Qitianling are three similar and representative metaluminous A-type tin granites in the western Nanling Range, China. They all have a high oxidization state with magnetite as the dominant Fe-Ti oxide. This study presents an understanding of systematic mineralogy of Sn-bearing minerals (biotite, titanite, magnetite and cassiterite) in the three granites. Biotite has an annite composition and both electron-microprobe and LA-ICP-MS analyses indicate trace amounts of tin in biotite (approximately 100-20 ppm). Chloritization of biotite is accompanied by formation of Sn-rich rutile and cassiterite. Titanite has a long history of crystallization from the early-magmatic stage through the late-magmatic stage to the hydrothermal stage. Owing to its solid-solution relationship with malayaite (CaSnSiO5), titanite always contains tin to various extents. Early-magmatic titanite contains about 0.5 wt.% SnO2, while the late-magmatic titanite is markedly enriched in tin (on average 14.8 and 3.4 SnO2 in titanite from the Qitianling and Huashan granites, respectively). Magnetite grains typically display a trellis structure with ilmenite lamellae, where microinclusions of cassiterite (<1 μm in size) are present. This is likely consistent with features of the "oxy-exsolution" process of Sn-bearing titanomagnetite precursor. Cassiterite may be observed as late-magmatic phase, but most commonly appears as an alteration product of other primary minerals. All tin-bearing minerals in the three granites record a complete process of tin mineralization in granite. The features of tin in primary biotite, titanite and magnetite reflect an initial enrichment during the early stage of magmatic crystallization of the Huashan, Guposhan and Qitianling granites. Association of interstitial Sn-titanite and cassiterite suggests further tin enrichment related to fractional crystallization of granitic magmas. Fluids and alteration of primary minerals play an important role in the

  13. 30 CFR 550.261 - What environmental impact analysis (EIA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...), existing offshore and onshore infrastructure (including major sources of supplies, services, energy, and...) information must accompany the DPP or DOCD? 550.261 Section 550.261 Mineral Resources BUREAU OF OCEAN ENERGY... potential impacts; (4) Describe any alternatives to your proposed development and production activities...

  14. 30 CFR 550.261 - What environmental impact analysis (EIA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...), existing offshore and onshore infrastructure (including major sources of supplies, services, energy, and...) information must accompany the DPP or DOCD? 550.261 Section 550.261 Mineral Resources BUREAU OF OCEAN ENERGY... potential impacts; (4) Describe any alternatives to your proposed development and production activities...

  15. 30 CFR 550.261 - What environmental impact analysis (EIA) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...), existing offshore and onshore infrastructure (including major sources of supplies, services, energy, and...) information must accompany the DPP or DOCD? 550.261 Section 550.261 Mineral Resources BUREAU OF OCEAN ENERGY... potential impacts; (4) Describe any alternatives to your proposed development and production activities...

  16. 30 CFR 550.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) information must accompany the EP? 550.214 Section 550.214 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans... adversely affect your proposed drilling operations. (g) High-resolution seismic lines. A copy of the...

  17. 30 CFR 550.256 - What related facilities and operations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... information must accompany the DPP or DOCD? 550.256 Section 550.256 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL... proposed development and production activities: (1) Drilling units; (2) Production platforms; (3)...

  18. 30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) information must accompany the DPP or DOCD? 550.244 Section 550.244 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL... subsurface geologic and manmade features and conditions that may adversely affect your proposed...

  19. 30 CFR 550.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) information must accompany the EP? 550.214 Section 550.214 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans... adversely affect your proposed drilling operations. (g) High-resolution seismic lines. A copy of the...

  20. 30 CFR 550.256 - What related facilities and operations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... information must accompany the DPP or DOCD? 550.256 Section 550.256 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL... proposed development and production activities: (1) Drilling units; (2) Production platforms; (3)...

  1. 30 CFR 550.256 - What related facilities and operations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... information must accompany the DPP or DOCD? 550.256 Section 550.256 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL... proposed development and production activities: (1) Drilling units; (2) Production platforms; (3)...

  2. 30 CFR 550.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) information must accompany the EP? 550.214 Section 550.214 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans... adversely affect your proposed drilling operations. (g) High-resolution seismic lines. A copy of the...

  3. 30 CFR 550.224 - What information on support vessels, offshore vehicles, and aircraft you will use must accompany...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What information on support vessels, offshore... information on support vessels, offshore vehicles, and aircraft you will use must accompany the EP?...

  4. 30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) information must accompany the DPP or DOCD? 550.244 Section 550.244 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL... subsurface geologic and manmade features and conditions that may adversely affect your proposed...

  5. 30 CFR 550.224 - What information on support vessels, offshore vehicles, and aircraft you will use must accompany...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What information on support vessels, offshore... information on support vessels, offshore vehicles, and aircraft you will use must accompany the EP?...

  6. 30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) information must accompany the DPP or DOCD? 550.244 Section 550.244 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL... subsurface geologic and manmade features and conditions that may adversely affect your proposed...

  7. 30 CFR 550.224 - What information on support vessels, offshore vehicles, and aircraft you will use must accompany...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What information on support vessels, offshore... information on support vessels, offshore vehicles, and aircraft you will use must accompany the EP?...

  8. Review: Regional land subsidence accompanying groundwater extraction

    USGS Publications Warehouse

    Galloway, Devin L.; Burbey, Thomas J.

    2011-01-01

    The extraction of groundwater can generate land subsidence by causing the compaction of susceptible aquifer systems, typically unconsolidated alluvial or basin-fill aquifer systems comprising aquifers and aquitards. Various ground-based and remotely sensed methods are used to measure and map subsidence. Many areas of subsidence caused by groundwater pumping have been identified and monitored, and corrective measures to slow or halt subsidence have been devised. Two principal means are used to mitigate subsidence caused by groundwater withdrawal—reduction of groundwater withdrawal, and artificial recharge. Analysis and simulation of aquifer-system compaction follow from the basic relations between head, stress, compressibility, and groundwater flow and are addressed primarily using two approaches—one based on conventional groundwater flow theory and one based on linear poroelasticity theory. Research and development to improve the assessment and analysis of aquifer-system compaction, the accompanying subsidence and potential ground ruptures are needed in the topic areas of the hydromechanical behavior of aquitards, the role of horizontal deformation, the application of differential synthetic aperture radar interferometry, and the regional-scale simulation of coupled groundwater flow and aquifer-system deformation to support resource management and hazard mitigation measures.

  9. Mechanical Surface Waves Accompany Action Potential Propagation

    NASA Astrophysics Data System (ADS)

    Machta, Benjamin; El Hady, Ahmed

    2015-03-01

    The action potential (AP) is the basic mechanism by which information is transmitted along neuronal axons. Although the excitable nature of axons is understood to be primarily electrical, many experimental studies have shown that a mechanical displacement of the axonal membrane co-propagates with the electrical signal. While the experimental evidence for co-propagating mechanical waves is diverse and compelling, there is no consensus for their physical underpinnings. We present a model in which these mechanical displacements arise from the driving of mechanical surface waves, in which potential energy is stored in elastic deformations of the neuronal membrane and cytoskeleton while kinetic energy is stored in the movement of the axoplasmic fluid. In our model these surface waves are driven by the traveling wave of electrical depolarization that characterizes the AP, altering the electrostatic forces across the membrane as it passes. Our model allows us to predict the shape of the displacement that should accompany any traveling wave of voltage, including the well-characterized AP. We expect our model to serve as a framework for understanding the physical origins and possible functional roles of these AWs in neurobiology. See Arxiv/1407.7600

  10. Photolysis Accompanying Peptide Absorption in Proteins

    PubMed Central

    Wilson, W. David; Foster, Joseph F.

    1972-01-01

    Exposure of proteins and polypeptides to ultraviolet radiation below 240 nm produces peptide cleavage which may or may not be accompanied by observable changes in conformation and optical rotary dispersion (ORD) properties, depending on the stability of the secondary and tertiary structure of the macromolecule under the experimental conditions. Helical and coiled forms of poly-L-glutamic acid undergo degradation at similar rates but only the helical form shows a significant change in rotatory properties. The helical form of poly-L-lysine, but neither the coiled nor β forms, shows a change in [α]233 on irradiation at 233 nm. β-Lactoglobulin shows essentially no change in [α]233 on irradiation in either dilute salt solution or 4 M urea at room temperature; however, in 4 M urea at 56°C a large change occurs. A model is developed which shows that studies of the effect of radiation on ORD properties may be useful in providing information on possible intermediate steps in protein denaturation. The method is illustrated with results on bovine plasma albumin. A quantum yield, 4.3 × 10-3 moles/einstein, was obtained for peptide cleavage in this protein at 225 nm. These studies, based on gel electrophoresis, also showed that the fragments produced are essentially random, suggesting that transfer of energy from aromatic residues is not an important contributor to the peptide photolysis. Possible errors which could arise in ORD and other studies involving intense ultraviolet radiation are considered. PMID:5063838

  11. Elastic Properties of Mantle Minerals

    NASA Astrophysics Data System (ADS)

    Duffy, T. S.; Stan, C. V.

    2012-12-01

    The most direct information about the interior structure of the Earth comes from seismic wave velocities. Interpretation of seismic data requires an understanding of how sound velocities and elastic properties of minerals vary with pressure, temperature, crystal structure, and composition as well as the role of anelasticity, melts, etc. More generally, elastic moduli are important for understanding many solid-state phenomena including mechanical stability, interatomic interactions, material strength, compressibility, and phase transition mechanisms. The database of mineral elasticity measurements has been growing rapidly in recent years. In this work, we report initial results of an ongoing survey of our current knowledge of mineral elasticity at both ambient conditions and high pressures and temperatures. The analysis is selective, emphasizing single crystal measurements but also incorporating polycrystalline measurements and volume compression data as appropriate. The goal is to synthesize our current understanding of mineral elasticity in terms of structure and composition, and to identify the major remaining needs for experimental and theoretical work. Clinopyroxenes (Cpx) provide an example of our approach. A wide range of clinopyroxene compositions are found geologically and Mg-, Ca-, and Na-rich clinopyroxenes are expected to be important components in the upper mantle. The single-crystal elastic properties of a number of endmember Cpx compositions have been measured and these exhibit a range of ~25% in shear velocity. Those with monovalent cations (spodumene, jadeite) in the M2 site exhibit the highest velocities while Fe-rich (hendenbergit, acmite) compositions have the lowest velocities. The effects on velocity due to a wide range of chemical substitutions can be defined, but there are important discrepancies and omissions in the database. New measurements of omphacites, intermediate diopside-hedenbergite compositions, aegerine/acmite, augite, etc. are

  12. Mineral of the month: garnet

    USGS Publications Warehouse

    Olson, Donald

    2005-01-01

    Garnet is the general name given to a group of complex silicate minerals, all with isometric crystal structure, similar properties and chemical compositions. Garnet occurs in every color of the spectrum except blue, but it is most commonly red, purple, brown and green. Garnet necklaces dating from the Bronze Age have been found in graves and also among the ornaments adorning the oldest Egyptian mummies.

  13. 16 CFR 1500.125 - Labeling requirements for accompanying literature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Labeling requirements for accompanying literature. 1500.125 Section 1500.125 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL... REGULATIONS § 1500.125 Labeling requirements for accompanying literature. When any accompanying...

  14. Compressibility changes accompanying conformational transitions of apomyoglobin.

    PubMed

    Taulier, Nicolas; Beletskaya, Irina V; Chalikian, Tigran V

    2005-11-01

    We used high-precision density and ultrasonic velocity measurements to characterize the native (N), molten globule (MG), and unfolded (U) conformations of apomyoglobin. The molten globule states that were studied in this work include the MG(pH4)(NaCl) state observed at pH 4 and 20 mM NaCl, the MG(pH4)(NaTCA) state observed at pH 4 and 20 mM sodium trichloracetate (NaTCA), the MG(pH2)(NaCl) state observed at pH 2 and 200 mM NaCl, and the MG(pH2)(NaTCA) state observed at pH 2 and 20 mM NaTCA. We used our densimetric and acoustic data to evaluate changes in adiabatic compressibility associated with the acid- or salt-induced N-to-MG, MG-to-U, MG-to-MG, and U-to-MG transitions of the protein. The N-to-MG(pH4)(NaCl) and N-to-MG(pH4)(NaTCA) transitions are accompanied by decreases in compressibility of -(3.0 +/- 0.6) x 10(-6) and -(2.0 +/- 0.6) x 10(-6) cm3 g(-1)bar(-1), respectively. The N-to-MG(pH2)(NaCl) and N-to-MG(pH2)(NaTCA) transitions are associated with compressibility changes of -(4.9 +/- 1.1) x 10(-6) and (0.7 +/- 0.9) x 10(-6) cm3 g(-1) bar(-1), respectively. We interpret these data in terms of the degree of unfolding of the various molten globule forms of apomyoglobin. In general, our compressibility data reveal significant disparities between the various equilibrium molten globule states of apomyoglobin while also quantitatively characterizing each of these states. Volumetric insights provided by our data facilitate gaining a better understanding of the folding pathways, intermediates, and kinetics of apomyoglobin folding.

  15. The American Museum of Natural History Mineral Library for Spectroscopic Standards

    NASA Astrophysics Data System (ADS)

    Nissinboim, A.; Ebel, D. S.; Harlow, G. E.; Boesenberg, J. S.; Sherman, K. M.; Lewis, E. R.; Brusentsova, T. N.; Peale, R. E.; Lisse, C. M.; Hibbitts, C. A.

    2010-03-01

    Minerals from the AMNH collections are highly characterized (crystal XRD, EMPA), powdered <2 µm, reanalyzed (SEM, powder XRD), and transmission IR spectra analyzed for Herschel PACS. Library minerals will also serve reflectance spectra needs.

  16. Crystalline-state reaction of cobaloxime complexes accompanying conformational change1

    NASA Astrophysics Data System (ADS)

    Sasada, Yoshio; Ohashi, Yuji

    1985-01-01

    In the crystals of some cobaloxime complexes, racemization of chiral group bonded to Co proceeds by X-ray irradiation without degradation of crystallinity. Racemization of methoxycarbonylethyl (mce) group has been examined for five cobaloxime complexes with different base as the second axial ligand, three of which did not give any indication of the reaction. Their crystal structures well explain the inactivity. Every stage of the change in the reactive crystals (base 4-chloropyridine, I; pyridine, II) has been revealed by X-ray analysis. In I, the mce groups suffer configurational and conformational changes at high temperature cooperatively. In II, rapid desolvation at room temperature is accompanied by conformational change of mce, and at 343 K random inversion occurs.

  17. Kinetics of gypsum nucleation and crystal growth from Dead Sea brine

    NASA Astrophysics Data System (ADS)

    Reznik, Itay J.; Gavrieli, Ittai; Ganor, Jiwchar

    2009-10-01

    The Dead Sea brine is supersaturated with respect to gypsum ( Ω = 1.42). Laboratory experiments and evaluation of historical data show that gypsum nucleation and crystal growth kinetics from Dead Sea brine are both slower in comparison with solutions at a similar degree of supersaturation. The slow kinetics of gypsum precipitation in the Dead Sea brine is mainly attributed to the low solubility of gypsum which is due to the high Ca 2+/SO 42- molar ratio (115), high salinity (˜280 g/kg) and to Na + inhibition. Experiments with various clay minerals (montmorillonite, kaolinite) indicate that these minerals do not serve as crystallization seeds. In contrast, calcite and aragonite which contain traces of gypsum impurities do prompt precipitation of gypsum but at a considerable slower rate than with pure gypsum. This implies that transportation inflow of clay minerals, calcite and local crystallization of minerals in the Dead Sea does not prompt significant heterogeneous precipitation of gypsum. Based on historical analyses of the Dead Sea, it is shown that over the last decades, as inflows to the lake decreased and its salinity increased, gypsum continuously precipitated from the brine. The increasing salinity and Ca 2+/SO 42- ratio, which results from the precipitation of gypsum, lead to even slower kinetics of nucleation and crystal growth, which resulted in an increasing degree of supersaturation with respect to gypsum. Therefore, we predict that as the salinity of the Dead Sea brine continues to increase (accompanied by Dead Sea water level decline), although gypsum will continuously precipitate, the degree of supersaturation will increase furthermore due to progressively slower kinetics.

  18. Cu-Zn slags from Røros (Norway): a case study of rapid cooling and crystal nucleation

    NASA Astrophysics Data System (ADS)

    Warchulski, Rafał; Szopa, Krzysztof

    2014-09-01

    The mining town of Røros located in central Norway was established in 1644 and it is known of historical mining industry related to copper. Røros was designated as an UNESCO World Heritage Site in 1980 on the base of mining culture represented by, e.g., unique wooden architecture. Slag pieces are composed of three parts differing in glass to crystallites ratio. Røros slags are composed of olivine- and pyroxene- group minerals accompanied by sulphides, with glass in the interstices. Temperature gradient and volatiles content were determined as the main factor influencing crystallization process in this material

  19. Cu-Zn Slags from R⊘ros (Norway): A Case Study of Rapid Cooling and Crystal Nucleation

    NASA Astrophysics Data System (ADS)

    Warchulski, Rafał; Szopa, Krzysztof

    2014-09-01

    The mining town of R⊘ros located in central Norway was established in 1644 and it is known of historical mining industry related to copper. R⊘ros was designated as an UNESCO World Heritage Site in 1980 on the base of mining culture represented by, e.g., unique wooden architecture. Slag pieces are composed of three parts differing in glass to crystallites ratio. R⊘ros slags are composed of olivine- and pyroxene- group minerals accompanied by sulphides, with glass in the interstices. Temperature gradient and volatiles content were determined as the main factor influencing crystallization process in this material.

  20. Phase Transition Mechanisms in the Mineral Titanite CaTiOSiO4 Under High Pressure - a X-ray Single Crystal Study Between 7 GPa and 10 GPa

    NASA Astrophysics Data System (ADS)

    Rath, S.; Kunz, M.; Miletich, R.

    2001-12-01

    The monoclinic mineral titanite is a common accessory in many acid and intermediate igneous rock, gneises, mica shists and amphiboles. The structure of titanite is characterized by corner-linked chains of TiO6 -octahedra parallel to [100] connected via isolated SiO4 -tetrahedra. CaO7 polyhedra build chains along [101]. The octahedral Ti atoms show typical out-of-center distortions. Its behavior under high pressure can give information about the driving forces of the phase transition in ABOCO4 silicates. The behavior of titanite under high pressure has been studied up to 7 GPa and 850oK with powder diffraction, respectively [1], [2], [3] and several phase transitions were found. The structure remains monoclinic but changes from P21/a to A2/a at 3.6 GPa. Here we present evidence for a new A2/a P-1 phase transition at 10.5 GPa. At this pressure the cell metric decreased to the following values: a= 6.829(4) Å , b= 8.594(2) Å , c= 6.352(1) Å, α = 90.18(2)° , β = 112.78(2)° , γ = 89.70(2)° and V= 343.7(2) Å3. Structure refinement results of high-pressure X-ray single crystal studies at pressures from 7 to 10 GPa will be presented. In addition, we compare the titanite results to the phase transition in the topological identical malayaite CaSnSiO_4 at 5 GPa, where a similar phase transition has previously been observed [4]. [1] Angel, R.J.; Kunz, M.; Miletich, R.; Woodland, A.B.; Koch, M. and Xirouchakis, D. (1999); High-pressure phase transition in CaTiOSiO_4 titanite; Phase Transitions, 68, 533 - 543 [2] Bismayer, U.; Zhang, M.; Groat, L.A.; Salje, E.K.H and Meyer, H.-W. (1999); The \\beta - \\gamma Phase Transition in Titanite and the Isosymmetric Analogue in Malayaite; Phase Transitions, 68, 545 - 556 [3] Kunz, M., Arlt, T. and Stolz, J. (2000): In situ powder diffraction of titanite (CaTiSiO_4) at high pressure and high temperature, American Mineralogist, 85, 1465 - 1473 [4] Rath, St, Kunz, M. and Miletich, R. (2001) Pressure induced phase transition in

  1. Tatarinovite Ca3Al(SO4)[B(OH)4](OH)6 · 12H2O, a new ettringite-group mineral from the Bazhenovskoe deposit, Middle Urals, Russia, and its crystal structure

    NASA Astrophysics Data System (ADS)

    Chukanov, N. V.; Kasatkin, A. V.; Zubkova, N. V.; Britvin, S. N.; Pautov, L. A.; Pekov, I. V.; Varlamov, D. A.; Bychkova, Ya. V.; Loskutov, A. B.; Novgorodova, E. A.

    2016-12-01

    A new mineral, tatarinovite, ideally Ca3Al(SO4)[B(OH)4](OH)6 · 12H2O, has been found in cavities of rhodingites at the Bazhenovskoe chrysotile asbestos deposit, Middle Urals, Russia. It occurs (1) colorless, with vitreous luster, bipyramidal crystals up to 1 mm across in cavities within massive diopside, in association with xonotlite, clinochlore, pectolite and calcite, and (2) as white granular aggregates up to 5 mm in size on grossular with pectolite, diopside, calcite, and xonotlite. The Mohs hardness is 3; perfect cleavage on (100) is observed. D meas = 1.79(1), D calc = 1.777 g/cm3. Tatarinovite is optically uniaxial (+), ω = 1.475(2), ɛ = 1.496(2). The IR spectrum contains characteristic bands of SO4 2-, CO3 2-, B(OH)4 -, B(OH)3, Al(OH)6 3-, Si(OH)6 2-, OH-, and H2O. The chemical composition of tatarinovite (wt %; ICP-AES; H2O was determined by the Alimarin method; CO2 was determined by selective sorption on askarite) is as follows: 27.40 CaO, 4.06 B2O3, 6.34 A12O3, 0.03 Fe2O3, 2.43 SiO2, 8.48 SO3, 4.2 CO2, 46.1 H2O, total is 99.04. The empirical formula (calculated on the basis of 3Ca apfu) is H31.41Ca3.00(Al0.76Si0.25)Σ1.01 · (B0.72S0.65C0.59)Σ1.96O24.55. Tatarinovite is hexagonal, space gr. P63, a = 11.1110(4) Å, c = 10.6294(6) Å, V = 1136.44(9) A3, Z = 2. Its crystal chemical formula is Ca3(Al0.70Si0.30) · {[SO4]0.34[B(OH)4]0.33[CO3]0.24}{[SO4]0.30[B(OH)4]0.34[CO3]0.30[B(OH)3]0.06}(OH5·73O0.27) · 12H2O. The strongest reflections of the powder X-ray diffraction pattern [ d, Å ( I, %) ( hkl)] are 9.63 (100) (100), 5.556 (30) (110), 4.654 (14) (102), 3.841 (21) (112), 3.441 (12) (211), 2.746 (10) (302), 2.538 (12) (213). Tatarinovite was named in memory of the Russian geologist and petrologist Pavel Mikhailovich Tatarinov (1895-1976), a well-known specialist in chrysotile asbestos deposits. Type specimens have been deposited at the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow.

  2. Influence of the mineral staggering on the elastic properties of the mineralized collagen fibril in lamellar bone.

    PubMed

    Vercher-Martínez, Ana; Giner, Eugenio; Arango, Camila; Fuenmayor, F Javier

    2015-02-01

    In this work, a three-dimensional finite element model of the staggered distribution of the mineral within the mineralized collagen fibril has been developed to characterize the lamellar bone elastic behavior at the sub-micro length scale. Minerals have been assumed to be embedded in a collagen matrix, and different degrees of mineralization have been considered allowing the growth of platelet-shaped minerals both in the axial and the transverse directions of the fibril, through the variation of the lateral space between platelets. We provide numerical values and trends for all the elastic constants of the mineralized collagen fibril as a function of the volume fraction of mineral. In our results, we verify the high influence of the mineral overlapping on the mechanical response of the fibril and we highlight that the lateral distance between crystals is relevant to the mechanical behavior of the fibril and not only the mineral overlapping in the axial direction.

  3. Mineralized aplite—pegmatite at Jabal Sa'id, Hijaz region, Kingdom of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Hackett, Damien

    The Jabal Sa'id aplite—pegmatite, located at 23°49'03″N, 40°56'30″E, is part of the Jabal Hadb ash Sharar granite complex and resulted from emplacement of a residual volatile-rich fraction of alkali granite magma dominantly above a chilled carapace. Mineralization is layered, with four peak grades in layers 20-25 m wide, one of which may represent a mineral resource with greater potential than the aplite—pegmatite as a whole. The grades of all elements, except Zr, increase towards the upper part of the body. Chemical composition is extremely variable. Major-oxide data confirm previously determined geochemical characteristics and genetic relationships that suggested this body is an apogranite. However, the abundant new data also show that differences between the aplite—pegmatite and cognate alkali microgranite are not as great as previously reported, except for Na 2O which is extremely depleted in the apogranite. REE data support suggested genetic relationships and indicate that feldspar fractionation was important during crystallization. They also show that the content of HREE is comparatively constant throughout the aplite—pegmatite, and that variations in total REE content are caused by variations in the content of LREE. Bastnaesite and synchysite-(Y) are the principal rare-earth-element minerals, and are accompanied by monazite and synchesite; pyrochlore and thorite are also important ore minerals. Other elements concentrated in the aplite—pegmatite, such as Ta, Sn and U, occur only in solid solution in these minerals. The grain size of the ore minerals is commonly in the range 0.02-0.2 mm, and the grain size of gangue minerals, quartz, microcline and lesser amounts of aegirine and arfvedsonite, is typically in the range 1.0-4.0 mm. The ore minerals occur typically along gangue mineral boundaries. Zoning within the body permits calculation of high- and low-grade reserves which correspond to the upper and lower part of the apogranite.

  4. Mineral spirits poisoning

    MedlinePlus

    Mineral spirits are liquid chemicals used to thin paint and as a degreaser. Mineral spirits poisoning occurs ... be found in: Mineral spirits ( Stoddard solvent ) Some paints Some floor and furniture waxes and polishes Some ...

  5. Citrate bridges between mineral platelets in bone.

    PubMed

    Davies, Erika; Müller, Karin H; Wong, Wai Ching; Pickard, Chris J; Reid, David G; Skepper, Jeremy N; Duer, Melinda J

    2014-04-08

    We provide evidence that citrate anions bridge between mineral platelets in bone and hypothesize that their presence acts to maintain separate platelets with disordered regions between them rather than gradual transformations into larger, more ordered blocks of mineral. To assess this hypothesis, we take as a model for a citrate bridging between layers of calcium phosphate mineral a double salt octacalcium phosphate citrate (OCP-citrate). We use a combination of multinuclear solid-state NMR spectroscopy, powder X-ray diffraction, and first principles electronic structure calculations to propose a quantitative structure for this material, in which citrate anions reside in a hydrated layer, bridging between apatitic layers. To assess the relevance of such a structure in native bone mineral, we present for the first time, to our knowledge, (17)O NMR data on bone and compare them with (17)O NMR data for OCP-citrate and other calcium phosphate minerals relevant to bone. The proposed structural model that we deduce from this work for bone mineral is a layered structure with thin apatitic platelets sandwiched between OCP-citrate-like hydrated layers. Such a structure can explain a number of known structural features of bone mineral: the thin, plate-like morphology of mature bone mineral crystals, the presence of significant quantities of strongly bound water molecules, and the relatively high concentration of hydrogen phosphate as well as the maintenance of a disordered region between mineral platelets.

  6. Predicting complex mineral structures using genetic algorithms.

    PubMed

    Mohn, Chris E; Kob, Walter

    2015-10-28

    We show that symmetry-adapted genetic algorithms are capable of finding the ground state of a range of complex crystalline phases including layered- and incommensurate super-structures. This opens the way for the atomistic prediction of complex crystal structures of functional materials and mineral phases.

  7. 9 CFR 93.508 - Articles accompanying swine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Articles accompanying swine. 93.508 Section 93.508 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Swine § 93.508 Articles accompanying swine. No...

  8. 9 CFR 93.508 - Articles accompanying swine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Articles accompanying swine. 93.508 Section 93.508 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Swine § 93.508 Articles accompanying swine. No...

  9. 9 CFR 93.508 - Articles accompanying swine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Articles accompanying swine. 93.508 Section 93.508 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Swine § 93.508 Articles accompanying swine. No...

  10. 9 CFR 93.508 - Articles accompanying swine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Articles accompanying swine. 93.508 Section 93.508 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Swine § 93.508 Articles accompanying swine. No...

  11. 9 CFR 93.508 - Articles accompanying swine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Articles accompanying swine. 93.508 Section 93.508 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Swine § 93.508 Articles accompanying swine. No...

  12. 9 CFR 93.307 - Articles accompanying horses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Articles accompanying horses. 93.307... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses § 93.307 Articles accompanying horses. No..., blankets, or other things used for or about horses governed by the regulations this part, shall be...

  13. 9 CFR 93.307 - Articles accompanying horses.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Articles accompanying horses. 93.307... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses § 93.307 Articles accompanying horses. No..., blankets, or other things used for or about horses governed by the regulations this part, shall be...

  14. 9 CFR 93.307 - Articles accompanying horses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Articles accompanying horses. 93.307... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses § 93.307 Articles accompanying horses. No..., blankets, or other things used for or about horses governed by the regulations this part, shall be...

  15. 9 CFR 93.307 - Articles accompanying horses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Articles accompanying horses. 93.307... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses § 93.307 Articles accompanying horses. No..., blankets, or other things used for or about horses governed by the regulations this part, shall be...

  16. 9 CFR 93.307 - Articles accompanying horses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Articles accompanying horses. 93.307... FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses § 93.307 Articles accompanying horses. No..., blankets, or other things used for or about horses governed by the regulations this part, shall be...

  17. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  18. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  19. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  20. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  1. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  2. 49 CFR 591.6 - Documents accompanying declarations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pursuant to § 591.5(j) shall be accompanied by the following documentation: (1) A declaration made pursuant to § 591.5(j)(1)(i), (ii), (iv), or (v) and (j)(2)(i) shall be accompanied by a letter from the Administrator authorizing importation pursuant to § 591.5(j)(1)(i), (ii), (iv), or (v) and (j)(2)(i). Any...

  3. 49 CFR 591.6 - Documents accompanying declarations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... pursuant to § 591.5(j) shall be accompanied by the following documentation: (1) A declaration made pursuant to § 591.5(j)(1)(i), (ii), (iv), or (v) and (j)(2)(i) shall be accompanied by a letter from the Administrator authorizing importation pursuant to § 591.5(j)(1)(i), (ii), (iv), or (v) and (j)(2)(i). Any...

  4. Control of Vertebrate Skeletal Mineralization by Polyphosphates

    PubMed Central

    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

  5. Vitamins and Minerals

    MedlinePlus

    ... and Minerals? What Do Vitamins and Minerals Do? Fuel for Growth Common Concerns en español Vitaminas y minerales Breakfast cereals advertise that they're packed with vitamins and minerals. Sports drinks claim they can rev up your flagging energy with a jolt of vitamins or minerals (sorry, ...

  6. Minerals in our environment

    USGS Publications Warehouse

    Weathers, Judy; Galloway, John; Frank, Dave

    2000-01-01

    Minerals are found everywhere in our daily lives. This poster depicts numerous items found throughout a home, and the mineral(s) or mineral resources used in the ingredients of, or construction/manufacturing of those items. Designed for K-8 Teachers this poster can be scaled and is printable at 36" x 60" and legible at 11" x 17" in size.

  7. Liquid Crystals in Education--The Basics

    ERIC Educational Resources Information Center

    Cepic, Mojca

    2012-01-01

    The introduction of teaching about liquid crystals is discussed from several points of view: the rationale why to teach them, the basics about liquid crystals or what the teacher should teach about them, the fundamental pre-knowledge of students required, the set of experiments accompanying the teaching and the brief report on the already…

  8. Biologically controlled minerals as potential indicators of life

    NASA Technical Reports Server (NTRS)

    Schwartz, D. E.; Mancinelli, R. L.; Kaneshiro, E.

    1991-01-01

    Minerals can be produced and deposited either by abiotic or biologic means. Regardless of their origin, mineral crystals reflect the environment conditions (e.g., temperature, pressure, chemical composition, and redox potential) present during crystal formation. Biologically-produced mineral crystals are grown or reworked under the control of their host organism and reflect an environment different from the abiotic environment. In addition, minerals of either biologic or abiotic origin have great longevities. For these reasons, biologically produced minerals have been proposed as biomarkers. Biomarkers are key morphological, chemical, and isotopic signatures of living systems that can be used to determine if life processes have occurred. Studies of biologically controlled minerals produced by the protist, Paramecium tetraurelia, were initiated since techniques have already been developed to culture them and isolate their crystalline material, and methods are already in place to analyze this material. Two direct crystalline phases were identified. One phase, whose chemical composition is high in Mg, was identified as struvite. The second phase, whose chemical composition is high in Ca, has not been previously found occurring naturally and may be considered a newly discovered material. Analyses are underway to determine the characteristics of these minerals in order to compare them with characteristics of these minerals in order to compare them with characteristics of minerals formed abiotically, but with the same chemical composition.

  9. Shaping Crystal-Crystal Phase Transitions

    NASA Astrophysics Data System (ADS)

    Du, Xiyu; van Anders, Greg; Dshemuchadse, Julia; Glotzer, Sharon

    Previous computational and experimental studies have shown self-assembled structure depends strongly on building block shape. New synthesis techniques have led to building blocks with reconfigurable shape and it has been demonstrated that building block reconfiguration can induce bulk structural reconfiguration. However, we do not understand systematically how this transition happens as a function of building block shape. Using a recently developed ``digital alchemy'' framework, we study the thermodynamics of shape-driven crystal-crystal transitions. We find examples of shape-driven bulk reconfiguration that are accompanied by first-order phase transitions, and bulk reconfiguration that occurs without any thermodynamic phase transition. Our results suggest that for well-chosen shapes and structures, there exist facile means of bulk reconfiguration, and that shape-driven bulk reconfiguration provides a viable mechanism for developing functional materials.

  10. Crystal structure of the mineral (Na,Ca,K){sub 2}(Ca,Na){sub 4}(Mg,Fe){sub 5}(Mg,Fe,Ti){sub 5}[Si{sub 12}Al{sub 4}O{sub 44}](F,O){sub 4}: a triclinic representative of the amphibole family

    SciTech Connect

    Rastsvetaeva, R. K. Aksenov, S. M.

    2012-05-15

    A mineral belonging to the amphibole family found at the Rothenberg paleovolcano (Eifel, Germany) was studied by single-crystal X-ray diffraction. The triclinic pseudomonoclinic unit-cell parameters are a = 5.3113(1) Angstrom-Sign , b = 18.0457(3) Angstrom-Sign ; c = 9.8684(2) Angstrom-Sign , {alpha} = 90.016(2) Degree-Sign , {beta} = 105.543(4) Degree-Sign , {gamma} = 89.985(2) Degree-Sign . The structure was solved by direct methods in sp. gr. P1 and refined to the R factor of 2.7% based on 6432 reflections with |F| > 3{sigma}(F) taking into account twinning. The mineral with the idealized formula (Na,Ca,K){sub 2}(Ca,Na){sub 4}(Mg,Fe){sub 5}(Mg,Fe,Ti){sub 5}[Si{sub 12}Al{sub 4}O{sub 44}](F,O){sub 4} has some symmetry and structural features that distinguish it from other minerals of this family.

  11. Crystal Meth

    MedlinePlus

    ... from Other Parents Stories of Hope Crystal meth Crystal meth Story of Hope by giovanni January 3, ... about my drug addiction having to deal with Crystal meth. I am now in recovery and fighting ...

  12. Crystal Meth

    MedlinePlus

    ... Navigation Home / Stories of Hope / Crystal meth Crystal meth Story Of Hope By giovanni January 3rd, 2013 ... my drug addiction having to deal with Crystal meth. I am now in recovery and fighting my ...

  13. Crystal Creations.

    ERIC Educational Resources Information Center

    Whipple, Nona; Whitmore, Sherry

    1989-01-01

    Presents a many-faceted learning approach to the study of crystals. Provides instructions for performing activities including crystal growth and patterns, creating miniature simulations of crystal-containing rock formations, charcoal and sponge gardens, and snowflakes. (RT)

  14. Magnetite-apatite mineralization in Khanlogh iron deposit, northwest of Neyshaboor, NE Iran

    NASA Astrophysics Data System (ADS)

    Najafzadeh Tehrani, Parvin; Asghar Calagari, Ali; Velasco Roldan, Francisco; Simmonds, Vartan; Siahcheshm, Kamal

    2016-04-01

    Khanlogh iron deposit lies on Sabzehvar-Ghoochan Cenozoic magmatic belt in northwest of Neyshaboor, NE Iran. The lithologic units in this area include a series of sub-volcanic intrusive rocks like diorite porphyry, quartz-diorite porphyry, and micro-granodiorite of Oligocene age. Mineralization in this area occurred as veins, dissemination, and open space filling in brecciated zones within the host sub-volcanic intrusive bodies. Three distinct types of mineral associations can be distinguished, (1) diopside-magnetite, (2) magnetite-apatite, and (3) apatite-calcite. Microscopic examinations along with SEM and EPMA studies demonstrated that magnetite is the most common ore mineral occurring as solitary crystals. The euhedral magnetite crystals are accompanied by lamellar destabilized ilmenite and granular fluorapatite in magnetite-apatite ores. The results of EPMA revealed that the lamellar ilmenite, relative to host magnetite crystal, is notably enriched in MgO and MnO (average of 3.3 and 2.6 wt%, respectively; n=5), whereas magnetite is slighter enriched in Ti (TiO2 around 1.8 wt%) being average of MgO, MnO and V2O3 of 0.6wt%, 0.2wt%, and 0.6 wt% (respectively; n=20). Minerals such as chlorapatite, calcite, and chalcedony are also present in the magnetite-apatite ores. The samples from apatite-calcite ores contain coarse crystals of apatite and rhomboedral calcite. The plot of the EPMA data of Khanlogh iron ore samples on diagram of TiO2-V2O5 (Hou et al, 2011) illustrated that the data points lies between the well-known Kiruna and El Laco (Chile) iron deposits. The magnetite crystals in the sub-volcanic host rocks were possibly formed by immiscible iron oxide fluids during magmatic stage. However, the magnetite and apatite existing in the veins and breccia zones may have developed by high temperature hydrothermal fluids. Studies done by Purtov and Kotelnikova (1993) proved that the proportion of Ti in magnetite is related to fluoride complex in the hydrothermal

  15. Moon's Pink Mineral

    NASA Astrophysics Data System (ADS)

    Martel, L. M. V.; Taylor, G. J.

    2014-12-01

    Since the 2010 remote-sensing discovery of lunar regolith rich in Mg-Al spinel on the rims and central peaks of impact craters and inner rings of basins on the Moon, researchers have been designing experiments to better understand the origin and formation history of spinel-rich rocks and what they mean for the construction of the lunar crust. The newly detected rock type is referred to as pink spinel anorthosite, or PSA, due to high plagioclase and low abundance (<5%) of mafic minerals such as olivine and pyroxene. Two recent studies tested specific hypotheses of PSA production on the Moon. Juliane Gross (American Museum of Natural History and the Lunar and Planetary Institute, LPI) and colleagues at the LPI, University of Hawaii, and NASA Johnson Space Center conducted experiments to model the crystallization of spinel in impact melts from impact events. Tabb Prissel (Brown University) and colleagues from Brown conducted experiments to model a plutonic formation of spinel from magma-wallrock interactions. In each study, comparisons of the remote sensing data with Apollo lunar samples or lunar meteorites were crucial for testing the PSA formation hypotheses with the experimental results. Definitive answers aren't in yet. PSA could form from impact melting of the right target rocks. Equally likely is PSA formation by reaction of basaltic magma and crust. One big unknown is the effect space weathering has in determining the amount of spinel in the PSA..

  16. Complex radiation-thermal history of Kaidun meteorite on data of track study of silicate minerals

    NASA Technical Reports Server (NTRS)

    Kashkarov, L. L.; Korotkova, N. N.; Skripnik, A. YA.

    1993-01-01

    The results of track study of approximately 80 individual silicate mineral crystals (ol, px, plag) picked out from Kaidun meteorite are presented. A wide range of observed rho(sub VH) value distributions indicate the complex irradiation history of Kaidun minerals. In one anortite crystal having two track groups with different parameters the pre-accretion irradiation traces were observed in all probability.

  17. 31 CFR 538.511 - Accompanied baggage authorized.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the United States directly or indirectly from Sudan are authorized to import into the United States... Sudan are authorized to export from the United States accompanied baggage normally incident to...

  18. 31 CFR 538.511 - Accompanied baggage authorized.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the United States directly or indirectly from Sudan are authorized to import into the United States... Sudan are authorized to export from the United States accompanied baggage normally incident to...

  19. 31 CFR 538.511 - Accompanied baggage authorized.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the United States directly or indirectly from Sudan are authorized to import into the United States... Sudan are authorized to export from the United States accompanied baggage normally incident to...

  20. 31 CFR 538.511 - Accompanied baggage authorized.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the United States directly or indirectly from Sudan are authorized to import into the United States... Sudan are authorized to export from the United States accompanied baggage normally incident to...

  1. 31 CFR 538.511 - Accompanied baggage authorized.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the United States directly or indirectly from Sudan are authorized to import into the United States... Sudan are authorized to export from the United States accompanied baggage normally incident to...

  2. 31 CFR 560.507 - Accompanied baggage authorized.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the United States directly or indirectly from Iran are authorized to import into the United States... Iran are authorized to export from the United States accompanied baggage normally incident to...

  3. 31 CFR 560.507 - Accompanied baggage authorized.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the United States directly or indirectly from Iran are authorized to import into the United States... Iran are authorized to export from the United States accompanied baggage normally incident to...

  4. 31 CFR 560.507 - Accompanied baggage authorized.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the United States directly or indirectly from Iran are authorized to import into the United States... Iran are authorized to export from the United States accompanied baggage normally incident to...

  5. Map accompanies a series of letters regarding modifications to the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Map accompanies a series of letters regarding modifications to the Aurora shops written during the later portion of 1878. Aurora shop scale 50 - 1' - Chicago, Burlington & Quincy Railroad, Roundhouse & Shops, Broadway & Spring Streets, Aurora, Kane County, IL

  6. Separation of Singing Voice from Music Accompaniment for Monaural Recordings

    DTIC Science & Technology

    2005-09-01

    Directory: pub/tech-report/2005 File in pdf format: TR61.pdf Separation of Singing Voice from Music Accompaniment for Monaural Recordings Yipeng Li...Abstract Separating singing voice from music accompaniment is very useful in many applications, such as lyrics recognition and alignment, singer...identification, and music information retrieval. Although speech separation has been extensively studied for decades, singing voice separation has been little

  7. SINGLE CRYSTAL NEUTRON DIFFRACTION.

    SciTech Connect

    KOETZLE,T.F.

    2001-03-13

    Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for information on magnetic scattering of neutrons see Unit 14.3. Instruments for single-crystal diffraction (single-crystal diffractometers or SCDs) are generally available at the major neutron scattering center facilities. Beam time on many of these instruments is available through a proposal mechanism. A listing of neutron SCD instruments and their corresponding facility contacts is included in an appendix accompanying this unit.

  8. CALCOSPHERULITES* ISOLATED FROM THE MINERALIZATION FRONT OF BONE INDUCE THE MINERALIZATION OF TYPE I COLLAGEN

    PubMed Central

    Midura, Ronald J.; Vasanji, Amit; Su, Xiaowei; Wang, Aimin; Midura, Sharon B.; Gorski, Jeff P.

    2007-01-01

    Previous work has suggested that “calcospherulites” actively participate in the mineralization of developing and healing bone. This study sought to directly test this hypothesis by developing a method to isolate calcospherulites and analyzing their capacity to seed mineralization of fibrillar collagen. The periosteal surface of juvenile rat tibial diaphysis was enriched in spherulites of ~0.5-micron diameter exhibiting a Ca/P ratio of 1.3. Their identity as calcospherulites was confirmed by their uptake of calcein at the tibial mineralization front 24 h following in vivo injection. Periosteum was dissected and unmineralized osteoid removed by collagenase in order to expose calcospherulites. Calcein-labeled calcospherulites were then released from the mineralization front by dispase digestion and isolated via fluorescence flow sorting. X-ray diffraction analysis revealed they contained apatite crystals (c-axis length of 17.5 ± 0.2 nm), though their Ca/P ratio of 1.3 is lower than that of hydroxyapatite. Much of their non-mineral phosphorous content was removed by ice-cold ethanol, elevating their Ca/P ratio to 1.6, suggesting the presence of phospholipids. Western blot analyses showed the presence of bone matrix proteins and type I collagen in these preparations. Incubating isolated calcospherulites in collagen hydrogels demonstrated that they could seed a mineralization reaction on type I collagen fibers in vitro. Ultrastructural analyses revealed crystals on the collagen fibers that were distributed rather uniformly along the fiber lengths. Furthermore, crystals were observed at distances well away from the observed calcospherulites. Our results directly support an active role for calcospherulites in inducing the mineralization of type I collagen fibers at the mineralization front of bone. PMID:17936099

  9. Mineral Resource Team 2010 Activities Summary

    DTIC Science & Technology

    2011-01-29

    sills of granite porphyry and aplite. Thus, the volcanic rocks comprise the roof of a very large intrusive igneous complex. Moreover, the volcanic...Deposit: Copper ores associated with intrusive igneous rocks , and the fluids that accompany them, during magmatic emplacement and crystallization...quartzite, paragneiss, and small intrusive igneous rocks . Findings from the USGS field report on those locations are summarized below, with additional

  10. Macromolecular recognition directs calcium ions to coccolith mineralization sites.

    PubMed

    Gal, Assaf; Wirth, Richard; Kopka, Joachim; Fratzl, Peter; Faivre, Damien; Scheffel, André

    2016-08-05

    Many organisms form elaborate mineralized structures, constituted of highly organized arrangements of crystals and organic macromolecules. The localization of crystals within these structures is presumably determined by the interaction of nucleating macromolecules with the mineral phase. Here we show that, preceding nucleation, a specific interaction between soluble organic molecules and an organic backbone structure directs mineral components to specific sites. This strategy underlies the formation of coccoliths, which are highly ordered arrangements of calcite crystals produced by marine microalgae. On combining the insoluble organic coccolith scaffold with coccolith-associated soluble macromolecules in vitro, we found a massive accretion of calcium ions at the sites where the crystals form in vivo. The in vitro process exhibits profound similarities to the initial stages of coccolith biogenesis in vivo.

  11. Fungal degradation of calcium-, lead- and silicon-bearing minerals.

    PubMed

    Adeyemi, Ademola O; Gadd, Geoffrey M

    2005-06-01

    The aim of this study was to examine nutritional influence on the ability of selected filamentous fungi to mediate biogenic weathering of the minerals, apatite, galena and obsidian in order to provide further understanding of the roles of fungi as biogeochemical agents, particularly in relation to the cycling of metals and associated elements found in minerals. The impact of three organic acid producing fungi (Aspergillus niger, Serpula himantioides and Trametes versicolor) on apatite, galena and obsidian was examined in the absence and presence of a carbon and energy source (glucose). Manifestation of fungal weathering included corrosion of mineral surfaces, modification of the mineral substrate through transformation into secondary minerals (i.e. crystal formation) and hyphal penetration of the mineral substrate. Physicochemical interactions of fungal metabolites, e.g. H+ and organic acids, with the minerals are thought to be the primary driving forces responsible. All experimental fungi were capable of mineral surface colonization in the absence and presence of glucose but corrosion of the mineral surface and secondary mineral formation were affected by glucose availability. Only S. himantioides and T. versicolor were able to corrode apatite in the absence of glucose but none of the fungi were capable of doing so with the other minerals. In addition, crystal formation with galena was entirely dependent on the availability of glucose. Penetration of the mineral substrates by fungal hyphae occurred but this did not follow any particular pattern. Although the presence of glucose in the media appeared to influence positively the mineral penetrating abilities of the fungi, the results obtained also showed that some geochemical change(s) might occur under nutrient-limited conditions. It was, however, unclear whether the hyphae actively penetrated the minerals or were growing into pre-existing pores or cracks.

  12. Bartering for Minerals.

    ERIC Educational Resources Information Center

    May, Kathie

    2002-01-01

    Presents an activity in which students are assigned occupations that rely on specific minerals. To obtain the needed minerals, students learn how to trade services and commodities. Includes details on preparation, modeling behaviors, and printed materials. (DDR)

  13. Mineral Spirits Purification Process.

    DTIC Science & Technology

    the mineral spirits to decompose 1,2- propanediol dinitrate and remove hydrogen cyandide and other gaseous decomposition produces, and then distill the mineral spirits from the remaining contaminants.

  14. New mineral occurrences and mineralization processes: Wuda coal-fire gas vents of Inner Mongolia

    SciTech Connect

    Stracher, G.B.; Prakash, A.; Schroeder, P.; McCormack, J.; Zhang, X.M.; Van Dijk, P.; Blake, D.

    2005-12-01

    Five unique mineral assemblages that include the sulfates millosevichite, alunogen, anhydrite, tschermigite, coquimbite, voltaite, and godovikovite, as well as the halide salammoniac and an unidentified phase, according to X-ray diffraction and EDS data, were found as encrustations on quartzofeldspathic sand and sandstone adjacent to coal-fire gas vents associated with underground coal fires in the Wuda coalfield of Inner Mongolia. The mineral assemblage of alunogen, coquimbite, voltaite, and the unidentified phase collected front the same gas vent, is documented for the first time. Observations suggest that the sulfates millosevichite, alunogen, coquimbite, voltaite, godovikovite, and the unidentified phase, crystallized in response to a complex sequence of processes that include condensation, hydrothermal alteration, crystallization from solution, fluctuating vent temperatures, boiling, and dehydration reactions, whereas the halide salammoniac crystallized during the sublimation of coal-fire gas. Tschermigite and anhydrite formed by the reaction of coal-fire gas with quartzofelds pathic rock or by hydrothermal alteration of this rock and crystallization from an acid-rich aqueous solution. These minerals have potentially important environmental significance and may be vectors for the transmission of toxins. Coal fires also provide insight for the recognition in the geologic record of preserved mineral assemblages that are diagnostic of ancient fires.

  15. Mineralization of Calcium Carbonate on Multifunctional Peptide Assembly Acting as Mineral Source Supplier and Template.

    PubMed

    Murai, Kazuki; Kinoshita, Takatoshi; Nagata, Kenji; Higuchi, Masahiro

    2016-09-13

    Crystal phase and morphology of biominerals may be precisely regulated by controlled nucleation and selective crystal growth through biomineralization on organic templates such as a protein. We herein propose new control factors of selective crystal growth by the biomineralization process. In this study, a designed β-sheet Ac-VHVEVS-CONH2 peptide was used as a multifunctional template that acted as mineral source supplier and having crystal phase control ability of calcium carbonate (CaCO3) during a self-supplied mineralization. The peptides formed three-dimensional nanofiber networks composed of assembled bilayer β-sheets. The assembly hydrolyzed urea molecules to one carbonate anion and two ammonium cations owing to a charge relay effect between His and Ser residues under mild conditions. CaCO3 was selectively mineralized on the peptide assembly using the generated carbonate anions on the template. Morphology of the obtained CaCO3 was fiber-like structure, similar to that of the peptide template. The mineralized CaCO3 on the peptide template had aragonite phase. This implies that CaCO3 nuclei, generated using the carbonate anions produced by the hydrolysis of urea on the surface of the peptide assembly, preferentially grew into aragonite phase, the growth axis of which aligned parallel to the direction of the β-sheet fiber axis.

  16. Possible uranium mineralization, Mineral Mountains, Utah

    USGS Publications Warehouse

    Miller, W. Roger; McHugh, John B.; Ficklin, Walter H.

    1979-01-01

    The Mineral Mountains block in west-central Utah is a horst whose core stands structurally high relative to all nearby basin-and-range fault blocks. Rocks of the Mineral Mountains range from Precambrian to Quaternary in age, but mostly consist of Tertiary granitic rocks. The range lies with the Wah Wah-Tusher mineral belt. Lead, silver, gold, and tungsten have been mined commercially. During a geochemical survey conducted in the summer of 1978, 30 water samples and 29 stream-sediment samples were collected from the Mineral Mountains area. The interpretation of simple plots of uranium concentrations and the results of a Q-mode factor analysis indicate that potential exists for uranium mineral deposits within the Mineral Mountains. The most favorable areas are in the granitic pluton near its contacts with sedimentary and metamorphic rocks. The most likely source of the uranium anomalies is uraninite-bearing epigenic veins along faults and fractures within the pluton. Three hypothetical models are proposed to account for the uranium mineralization.

  17. Minerals leasing for landowners

    SciTech Connect

    Not Available

    1983-01-01

    This report delineates the provisions of the legal codes of the 13 Southeastern states relating to minerals leasing. The introduction explains land ownership and land leasing in terms of mineral rights, and describes the basic elements which a lease conveyance must contain to be valid. A checklist gives the terms which must be included in all mineral leases.

  18. Phase equilibria study of pseudobrookite type minerals

    NASA Technical Reports Server (NTRS)

    Friel, J. J.

    1974-01-01

    Pseudobrookite, is found in volcanic rocks, and the mineral armalcolite ((Fe,Mg)Ti2O5) found in the Apollo 11 and subsequent lunar samples seems to be unique to the moon. In plutonic rocks on the earth, ilmenite and rutile were found with what appears to be an equilibrium liquidus texture, while on the moon armalcolite often appears to be the primary liquidus phase among Ti-oxides. This suggests that total pressure may be a factor in the formation of these minerals, and a knowledge of the phase relations in this system yields information about the pressure under which a given magma crystallized.

  19. Crystal growth of calcium phosphates - epitaxial considerations

    NASA Astrophysics Data System (ADS)

    Koutsoukos, P. G.; Nancollas, G. H.

    1981-05-01

    The growth of one crystalline phase on the surface of another that offers a good crystal lattice match, may be important in environmental, physiological and pathological mineralization processes. The epitaxial relationships and kinetics of growth of hydroxyapatite on crystals of dicalcium phosphate dihydrate, calcium fluoride and calcite have been studied at sustained low supersaturation with respect to hydroxyapatite. At the very low supersaturations, the crystallization of hydroxyapatite takes place without the formation of precursor phases. The experimental results are in agreement with theoretical predictions for epitaxial growth, while the kinetics of hydroxyapatite crystallization on the foreign substrates is the same as that for the growth of hydroxyapatite on synthetic hydroxyapatite crystals.

  20. Lineament analysis of mineral areas of interest in Afghanistan

    USGS Publications Warehouse

    Hubbard, Bernard E.; Mack, Thomas J.; Thompson, Allyson L.

    2012-01-01

    The purpose of this report and accompanying GIS data is to provide lineament maps that give one indication of areas that warrant further investigation for optimal bedrock water-well placement within 24 target areas for mineral resources (Peters and others, 2011). These data may also support the identification of faults related to modern seismic hazards (for example, Wheeler and others, 2005; Ruleman and others, 2007), as well as support studies attempting to understand the relationship between tectonic and structural controls on hydrothermal fluid flow, subsequent mineralization, and water-quality issues near mined and unmined mineral deposits (for example, Eppinger and others, 2007).

  1. Magmatic Processes and Systems Deduced from Single Crystals

    NASA Astrophysics Data System (ADS)

    Davidson, J.; Bezard, R. C.; Morgan, D. J.; Ginibre, C.

    2014-12-01

    When crystals grow in liquids the composition of their outermost layer will reflect that of the host with which they are in equilibrium and will therefore record the liquid composition, pressure and temperature.. Following separation from their sources, magmas differentiate. This change in liquid composition is driven largely by crystallisation in response to cooling or decompression. Other open system processes such as mixing and contamination are common. These can lead to abrupt changes in trace element and isotopic composition, accompanied by petrographic features, such as dissolution surfaces or zones of melt inclusions. Where such careful mineral-scale studies have been performed, the prevalence of open system processes is clear. In many cases these are shown by core-rim isotopic variations. Crystal-scale compositional variations in the context of whole rock compositions and petrography have allowed us to show crustal assimilation even from regions of supposedly oceanic crust such as the Lesser Antilles. In tandem with tracking magma evolution, core-rim analyses of appropriate crystals have also provided diffusion profiles which reflect timescales of magmatic processes. A key point, long recognised by Bruce Marsh, is that in situ geochemical data should be considered in a petrographic context in order to gain the most (and most credible) insights on the workings of magma systems from hand specimen to whole volcano/pluton scales: The petrographic microscope is not dead yet Identification of magmatic processes from in situ scrutiny allows us to synthesise the architectures and inner workings of magma systems. The evidence for interaction among magmas in many systems is compelling and suggests that many exist as stacked dike-sill arrangements with wall-rock focussed crystal growth and mush zones. These are consistent with many of the systematics suggested some time ago by Bruce Marsh

  2. Crystal structure of the NaCa(Fe{sup 2+}, Al, Mn){sub 5}[Si{sub 8}O{sub 19}(OH)](OH){sub 7} {center_dot} 5H{sub 2}O mineral: A new representative of the palygorskite group

    SciTech Connect

    Rastsvetaeva, R. K. Aksenov, S. M.; Verin, I. A.

    2012-01-15

    A specimen of a new representative of the palygorskite-sepiolite family from Aris phonolite (Namibia) is studied by single-crystal X-ray diffraction. The parameters of the triclinic (pseudomonoclinic) unit cell are as follows: a = 5.2527(2) Angstrom-Sign , b = 17.901(1) Angstrom-Sign , c = 13.727(1) Angstrom-Sign , {alpha} = 90.018(3) Degree-Sign , {beta} = 97.278(4) Degree-Sign , and {gamma} = 89.952(3) Degree-Sign . The structure is solved by the direct methods in space group P1-bar and refined to R = 5.5% for 4168 |F| > 7{sigma}(F) with consideration for twinning by the plane perpendicular to y (the ratio of the twin components is 0.52: 0.48). The crystal chemical formula (Z = 1) is (Na{sub 1.6}K{sub 0.2}Ca{sub 0.2})[Ca{sub 2}(Fe{sub 3.6}{sup 2+}Al{sub 1.6}Mn{sub 0.8})(OH){sub 9}(H{sub 2}O){sub 2}][(Fe{sub 3.9}{sup 2+}Ti{sub 0.1})(OH){sub 5} (H{sub 2}O){sub 2}][Si{sub 16}O{sub 38}(OH){sub 2}] {center_dot} 6H{sub 2}O, where the compositions of two ribbons of octahedra and a layer of Si tetrahedra are enclosed in brackets. A number of specific chemical, symmetrical, and structural features distinguish this mineral from other minerals of this family, in particular, from tuperssuatsiaite and kalifersite, which are iron-containing representatives with close unit cell parameters.

  3. Mineral particles, mineral fibers, and lung cancer

    SciTech Connect

    Churg, A.; Wiggs, B.

    1985-08-01

    The total fibrous and nonfibrous mineral content of the lung has been analyzed in a series of 14 men with lung cancer but no history of occupational dust exposure, and in a series of 14 control men matched for age, smoking history, and general occupational class. The lung cancer patients had an average of 525 +/- 369 X 10(6) exogenous mineral particles and 17.4 +/- 19.6 X 10(6) exogenous mineral fibers/g dry lung, while the controls had averages of 261 +/- 175 mineral particles and 4.7 +/- 3.2 X 10(6) mineral fibers/g dry lung. These differences are statistically significant for both particles and fibers. Kaolinite, talc, mica, feldspars, and crystalline silica comprised the majority of particles of both groups. Approximately 90% of the particles were smaller than 2 micron in diameter and approximately 60% smaller than 1 micron. In both groups, patients who had smoked more than 35 pack years had greater numbers of particles than patients who had smoked less than 35 pack years. It is concluded that, in this study, lungs from patients with lung cancer had statistically greater numbers of mineral particles and fibers than lungs from controls, and that smoking influences total long-term retention of particles from all sources.

  4. Integrated Spectroscopic Studies of Anhydrous Sulfate Minerals

    NASA Technical Reports Server (NTRS)

    Lane, M. D.; Bishop, J. L.; Dyar, M. D.; Cloutis, E.; Forray, F. L.; Hiroi, T.

    2005-01-01

    Sulfates have been identified in Martian soils and bedrock and are emerging as an important indicator for aqueous activity on Mars. Sulfate minerals can form in a variety of low-temperature (evaporitic; chemical-weathering) and high-temperature (volcanic/fumarolic; hydrothermal) environments and their formational environments can range from alkaline to acidic. Although sulfates generally form in the presence of water, not all sulfates are hydrous or contain water in their structures. Many of these anhydrous sulfates (Dana group 28; Strunz class 67A) are minerals that form as accompanying phases to the main minerals in ore deposits or as replacement deposits in sedimentary rocks. However, some form from thermal decomposition of OH or H2O-bearing sulfates, such as from the reaction [1]: jarosite = yavapaiite + Fe2O3 + H2O. Where known, the stability fields of these minerals all suggest that they would be stable under martian surface conditions [2]. Thus, anhydrous sulfate minerals may contribute to martian surface mineralogy, so they must be well-represented in spectral libraries used for interpretation of the Martian surface. We present here the preliminary results of an integrated study of emittance, reflectance, and Mossbauer spectroscopy of a suite of wel-lcharacterized anhydrous sulfates.

  5. Spondylolisthesis Accompanying Bilateral Pedicle Stress Fracture at Two Vertebrae

    PubMed Central

    Kim, Hyeun Sung; Lee, Won Tae

    2012-01-01

    There has been no report of bilateral pedicle stress fractures involving two vertebrae. The authors describe a unique case of spondylolisthesis accompanying a bilateral pedicle stress fracture involving two vertebrae. De novo development of spondylolisthesis at the L5-S1 vertebrae accompanying a bilateral pedicle stress fracture at L4 and L5 was observed in a 70-year-old woman. The patient's medical history was unremarkable and she did not have any predisposing factors except severe osteoporosis. Interbody fusion with bone cement augmented screw fixation was performed. Surgical treatment resulted in good pain management and improved functional recovery. PMID:22949973

  6. Boron isotopic compositions of some boron minerals

    SciTech Connect

    Oi, Takao; Musashi, Masaaki; Ossaka, Tomoko; Kakihana, Hidetake ); Nomura, Masao; Okamoto, Makoto )

    1989-12-01

    Boron minerals that have different structural formulae but are supposed to have the same geologic origin have been collected and analyzed for the {sup 11}B/{sup 10}B isotopic ratio. It has been reconfirmed that minerals of marine origin have higher {sup 11}B/{sup 10}B ratios than those of nonmarine origin. It has been found that the sequence of decreasing {sup 11}B/{sup 10}B values among the minerals with the same geologic origin is; borax, tincal, kernite (Na borates) > ulexite (Na/Ca borate) > colemanite, iyoite, meyerhofferite (Ca borates). This sequence is explainable on the basis of the difference in crystal structure among the minerals. That is, minerals with high BO{sub 3}/BO{sub 4} ratios, (the ratio of the number of the BO{sub 3} triangle units to the number of the BO{sub 4} tetrahedron units in the structural formula of a mineral) have higher {sup 11}B/{sup 10}B ratios.

  7. The role of phosphatases in the initiation of skeletal mineralization.

    PubMed

    Millán, José Luis

    2013-10-01

    Endochondral ossification is a carefully orchestrated process mediated by promoters and inhibitors of mineralization. Phosphatases are implicated, but their identities and functions remain unclear. Mutations in the tissue-nonspecific alkaline phosphatase (TNAP) gene cause hypophosphatasia, a heritable form of rickets and osteomalacia, caused by an arrest in the propagation of hydroxyapatite (HA) crystals onto the collagenous extracellular matrix due to accumulation of extracellular inorganic pyrophosphate (PPi), a physiological TNAP substrate and a potent calcification inhibitor. However, TNAP knockout (Alpl(-/-)) mice are born with a mineralized skeleton and have HA crystals in their chondrocyte- and osteoblast-derived matrix vesicles (MVs). We have shown that PHOSPHO1, a soluble phosphatase with specificity for two molecules present in MVs, phosphoethanolamine and phosphocholine, is responsible for initiating HA crystal formation inside MVs and that PHOSPHO1 and TNAP have nonredundant functional roles during endochondral ossification. Double ablation of PHOSPHO1 and TNAP function leads to the complete absence of skeletal mineralization and perinatal lethality, despite normal systemic phosphate and calcium levels. This strongly suggests that the Pi needed for initiation of MV-mediated mineralization is produced locally in the perivesicular space. As both TNAP and nucleoside pyrophosphohydrolase-1 (NPP1) behave as potent ATPases and pyrophosphatases in the MV compartment, our current model of the mechanisms of skeletal mineralization implicate intravesicular PHOSPHO1 function and Pi influx into MVs in the initiation of mineralization and the functions of TNAP and NPP1 in the extravesicular progression of mineralization.

  8. Petrologic evidence for thermal rejuvenation of crystal mush in the Bandelier Tuff

    NASA Astrophysics Data System (ADS)

    Wolff, J. A.; Wark, D. A.; Ramos, F. C.; Olin, P. H.

    2006-12-01

    The 1.6 Ma Otowi Member of the Bandelier Tuff consists of ~500 km3 of mineralogically, chemically and isotopically zoned high-silica rhyolite. The melt phase was saturated with trace amounts of zircon, chevkinite, britholite and allanite, and upward whole-pumice elemental enrichments and depletions in the tuff are predicted by crystallization-differentiation involving an assemblage bearing those minerals. Isotopic variations among glasses and feldspars have previously been attributed to roof-rock contamination (Wolff & Ramos, 2003), but new LA-ICPMS, ion probe and CL investigations of late-erupted glomerocryst-bearing pumice clasts indicate an additional role for magmatic recharge and thermal rejuvenation in affecting chemical gradients. First, trace element covariations in glasses at the submillimeter scale are distinct from those of whole pumices and require preferential non-modal melting of the trace phases. Second, Ti geothermometry of strongly CL-zoned quartz in glomerocrysts from the last-erupted products indicates an episode of partial quartz dissolution followed by higher-temperature regrowth. Third, this regrowth episode is also recorded among accompanying feldspar grains, which have rims enriched in Sr and Ba and with Pb isotope ratios distinct from crystal cores. These observations are consistent with a model in which an initially stratified magma body consisting of crystal-poor, highly differentiated rhyolite was underlain by cognate crystal mush residue, now represented by glomerocrysts. This body was disturbed by recharge and melting of the mush, with accompanying melt transfer, partial mingling of magma layers and roof-rock contamination, followed by an episode of recrystallization. Evidence that this recharge took place shortly before eruption (see abstract by Wark and Wolff) suggests that some of the observed zoning in the Bandelier Tuff, and possibly the eruption itself, occurred in response to chamber-wide thermal rejuvenation of a stagnant

  9. Magnetic susceptibilities of minerals

    USGS Publications Warehouse

    Rosenblum, Sam; Brownfield, I.K.

    2000-01-01

    Magnetic separation of minerals is a topic that is seldom reported in the literature for two reasons. First, separation data generally are byproducts of other projects; and second, this study requires a large amount of patience and is unusually tedious. Indeed, we suspect that most minerals probably are never investigated for this property. These data are timesaving for mineralogists who concentrate mono-mineralic fractions for chemical analysis, age dating, and for other purposes. The data can certainly be used in the ore-beneficiation industries. In some instances, magnetic-susceptibility data may help in mineral identification, where other information is insufficient. In past studies of magnetic separation of minerals, (Gaudin and Spedden, 1943; Tille and Kirkpatrick, 1956; Rosenblum, 1958; Rubinstein and others, 1958; Flinter, 1959; Hess, 1959; Baker, 1962; Meric and Peyre, 1963; Rojas and others, 1965; and Duchesne, 1966), the emphasis has been on the ferromagnetic and paramagnetic ranges of extraction. For readers interested in the history of magnetic separation of minerals, Krumbein and Pettijohn (1938, p. 344-346) indicated nine references back to 1848. The primary purpose of this paper is to report the magnetic-susceptibility data on as many minerals as possible, similar to tables of hardness, specific gravity, refractive indices, and other basic physical properties of minerals. A secondary purpose is to demonstrate that the total and best extraction ranges are influenced by the chemistry of the minerals. The following notes are offered to help avoid problems in separating a desired mineral concentrate from mixtures of mineral grains.

  10. Biological control of crystal texture: A widespread strategy for adapting crystal properties to function

    SciTech Connect

    Berman, A.; Leiserowitz, L.; Weiner, S.; Addadi, L. ); Hanson, J.; Koetzle, T.F. )

    1993-02-05

    Textures of calcite crystals from a variety of mineralized tissues belong to organisms from four phyla were examined with high-resolution synchrotron x-ray radiation. Significant differences in coherence length and angular spread were observed between taxonomic groups. Crystals from polycrystalline skeletal ensembles were more perfect than those that function as single-crystal elements. Different anistropic effects on crystal texture were observed for sea urchin and mollusk calcite crystals, whereas none was found for the foraminifer, Patellina, and the control calcite crystals. These results show that the manipulation of crystal texture in different organisms is under biological control and that crystal textures in some tissues are adapted to function. A better understanding of this apparently widespread biological phenomenon may provide new insights for improving synthetic crystal-containing materials. 18 refs., 3 figs., 1 tab.

  11. Virtual Crystallizer

    SciTech Connect

    Land, T A; Dylla-Spears, R; Thorsness, C B

    2006-08-29

    Large dihydrogen phosphate (KDP) crystals are grown in large crystallizers to provide raw material for the manufacture of optical components for large laser systems. It is a challenge to grow crystal with sufficient mass and geometric properties to allow large optical plates to be cut from them. In addition, KDP has long been the canonical solution crystal for study of growth processes. To assist in the production of the crystals and the understanding of crystal growth phenomena, analysis of growth habits of large KDP crystals has been studied, small scale kinetic experiments have been performed, mass transfer rates in model systems have been measured, and computational-fluid-mechanics tools have been used to develop an engineering model of the crystal growth process. The model has been tested by looking at its ability to simulate the growth of nine KDP boules that all weighed more than 200 kg.

  12. Crystal growing

    NASA Technical Reports Server (NTRS)

    Neville, J. P.

    1990-01-01

    One objective is to demonstrate the way crystals grow and how they affect the behavior of material. Another objective is to compare the growth of crystals in metals and nonmetals. The procedures, which involve a supersaturated solution of a salt that will separate into crystals on cooling and the pouring off of an eutectic solution to expose the crystals formed by a solid solution when an alloy of two metals forms a solid and eutectic solution on cooling, are described.

  13. Hypertrophic pachymeningitis accompanying neuromyelitis optica spectrum disorder: A case report.

    PubMed

    Kon, Tomoya; Nishijima, Haruo; Haga, Rie; Funamizu, Yukihisa; Ueno, Tatsuya; Arai, Akira; Suzuki, Chieko; Nunomura, Jin-ichi; Baba, Masayuki; Takahashi, Toshiyuki; Tomiyama, Masahiko

    2015-10-15

    We report a case of idiopathic cerebral hypertrophic pachymeningitis accompanying neuromyelitis optica spectrum disorder. No other identifiable cause of pachymeningitis was detected. Corticosteroid therapy was effective for both diseases. Hypertrophic pachymeningitis is closely related to autoimmune inflammatory disease of the central nervous system. This case supports the hypothesis that hypertrophic pachymeningitis can be a rare comorbidity of neuromyelitis optica spectrum disorder.

  14. Looking for Meaning. Instructional Manual to Accompany "Pixie".

    ERIC Educational Resources Information Center

    Lipman, Matthew; Sharp, Ann Margaret

    Designed to accompany "Pixie," a philosophy reader for students in grades three and four, this instructional manual presents discussion plans, games, philosophical activities, and reasoning exercises so that the concepts in the reader can be readily operationalized in the classroom. The "Pixie" program focuses on abstract reasoning, ambiguity, and…

  15. Teacher's Manual to Accompany "How to Get a Job."

    ERIC Educational Resources Information Center

    Webster, John D.

    Prepared for teachers of mentally handicapped students, this teacher's guide accompanies the student booklet, "How to Get A Job," and contains suggestions for learning activities and vocabulary development for each subdivision of all four major units in the student booklet: choosing the right kind of work, looking for the job, going on an…

  16. The Global Education Practicum: Perspectives from Accompanying Academics

    ERIC Educational Resources Information Center

    Lang, Catherine; Cacciattolo, Marcelle; Kidman, Gillian

    2017-01-01

    The benefits of international education experiences for students are well documented. The effect on the individual of international experiences has been researched and theorised by authors for at least the last 20 years. In this paper the experiences of three academics who accompanied pre-service teachers on a 3 week international practicum are…

  17. 19 CFR 12.6 - Affidavits required to accompany entry.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Importation of Certain Cheeses § 12.6 Affidavits required to accompany entry. (a) Cheeses produced in the member states of the European Communities shall... (excluding Puerto Rico), of the producer or exporter that the cheese has not received and will not...

  18. 9 CFR 93.208 - Articles accompanying poultry.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Articles accompanying poultry. 93.208... AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND POULTRY PRODUCTS;...

  19. 9 CFR 93.208 - Articles accompanying poultry.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Articles accompanying poultry. 93.208... AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND POULTRY PRODUCTS;...

  20. 9 CFR 93.208 - Articles accompanying poultry.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Articles accompanying poultry. 93.208... AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND POULTRY PRODUCTS;...

  1. 9 CFR 93.208 - Articles accompanying poultry.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Articles accompanying poultry. 93.208... AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND POULTRY PRODUCTS;...

  2. 9 CFR 93.208 - Articles accompanying poultry.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Articles accompanying poultry. 93.208... AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND POULTRY PRODUCTS;...

  3. 36 CFR 14.25 - Documents which must accompany application.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) Maps. Each application, other than an appropriation for Federal-aid highway purposes under Title 23, United States Code, section 317, must be accompanied by a map prepared on tracing linen, or on tracing... engineer or land surveyor. The map should comply with the following requirements: (1) The scale should be...

  4. 36 CFR 14.25 - Documents which must accompany application.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Maps. Each application, other than an appropriation for Federal-aid highway purposes under Title 23, United States Code, section 317, must be accompanied by a map prepared on tracing linen, or on tracing... engineer or land surveyor. The map should comply with the following requirements: (1) The scale should be...

  5. 36 CFR 14.25 - Documents which must accompany application.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Maps. Each application, other than an appropriation for Federal-aid highway purposes under Title 23, United States Code, section 317, must be accompanied by a map prepared on tracing linen, or on tracing... engineer or land surveyor. The map should comply with the following requirements: (1) The scale should be...

  6. 36 CFR 14.25 - Documents which must accompany application.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Maps. Each application, other than an appropriation for Federal-aid highway purposes under Title 23, United States Code, section 317, must be accompanied by a map prepared on tracing linen, or on tracing... engineer or land surveyor. The map should comply with the following requirements: (1) The scale should be...

  7. 9 CFR 93.314 - Horses, certification, and accompanying equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Horses, certification, and accompanying equipment. 93.314 Section 93.314 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND...

  8. 9 CFR 93.314 - Horses, certification, and accompanying equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Horses, certification, and accompanying equipment. 93.314 Section 93.314 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND...

  9. 9 CFR 93.314 - Horses, certification, and accompanying equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Horses, certification, and... PRODUCTS; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses § 93.314 Horses, certification, and accompanying equipment. (a) Horses offered for importation from any part of the world...

  10. 9 CFR 93.314 - Horses, certification, and accompanying equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Horses, certification, and... PRODUCTS; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses § 93.314 Horses, certification, and accompanying equipment. (a) Horses offered for importation from any part of the world...

  11. Hereditary nodular heterotopia accompanied by mega cisterna magna.

    PubMed

    Oda, T; Nagai, Y; Fujimoto, S; Sobajima, H; Kobayashi, M; Togari, H; Wada, Y

    1993-08-15

    This is the first report of hereditary nodular heterotopia accompanied by mega cisterna magna. Magnetic resonance imaging documented multiple bilateral subependymal nodules, which were isointense to gray matter. This disease entity is considered a dominant trait, since the mother and two daughters, half-sisters, were affected.

  12. 16 CFR 1500.125 - Labeling requirements for accompanying literature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Labeling requirements for accompanying literature. 1500.125 Section 1500.125 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL... includes or bears any directions for use (by printed word, picture, design, or combination thereof),...

  13. Notes to Accompany the BBC Television Series: Tele-France.

    ERIC Educational Resources Information Center

    Doyle, Terry; Kuhn, Michel

    These notes are designed to accompany a series of 10 British Broadcasting Corporation (BBC) television programs intended to give persons already familiar with French, an insight into aspects of contemporary Francophone societies. The programs revolve around various themes: (1) numbers and letters; (2) words and meanings; (3) eating patterns; (4)…

  14. 9 CFR 93.314 - Horses, certification, and accompanying equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... inspected on the premises of origin and found free of evidence of communicable disease and, insofar as can... region of origin, or if exported from Mexico, shall be accompanied either by such a certificate or by a..., vesicular stomatitis, or equine infectious anemia has occurred on the premises of origin or on...

  15. 31 CFR 545.507 - Accompanied baggage authorized.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Accompanied baggage authorized. 545.507 Section 545.507 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued... that are necessary for personal use incident to travel, that are not intended for any other person...

  16. Rare gases in cyclosilicates and cogenetic minerals

    NASA Technical Reports Server (NTRS)

    Saito, K.; Alexander, E. C., Jr.; Dragon, J. C.; Zashu, S.

    1984-01-01

    The cyclosilicate minerals, beryl, tourmaline, and cordierite, typically contain large amounts of He-4 and Ar-40 which are not in situ radiogenic products. In the study of excess rare gases in cyclosilicates, one of the most enigmatic observations is the age effect, a qualitative tendency for geologically older samples to contain more excess He-4 and Ar-40 than younger samples. The present investigation is concerned with measurements regarding the abundance and isotopic composition of all five rare gases in a number of cyclosilicates as well as in their cogenetic minerals. The significance of the obtained data is discussed. The data indicate that cyclosilicates sample the rare gases present in the environment in which they crystallize. This 'sampling' involves major elemental fractionations which are variable but mineral specific. Cyclosilicates can, therefore, be used to probe the isotopic ratios and elemental compositions.

  17. Intracellular minerals and metal deposits in prokaryotes.

    PubMed

    Edwards, K J; Bazylinski, D A

    2008-06-01

    Thanks to the work of Terrance J. Beveridge and other pioneers in the field of metal-microbe interactions, prokaryotes are well known to sequester metals and other ions intracellularly in various forms. These forms range from poorly ordered deposits of metals to well-ordered mineral crystals. Studies on well-ordered crystalline structures have generally focused on intracellular organelles produced by magnetotactic bacteria that are ubiquitous in terrestrial and marine environments that precipitate Fe(3)O(4) or Fe(3)S(4), Fe-bearing minerals that have magnetic properties and are enclosed in intracellular membranes. In contrast, studies on less-well ordered minerals have focused on Fe-, As-, Mn-, Au-, Se- and Cd-precipitates that occur intracellularly. The biological and environmental function of these particles remains a matter of debate.

  18. Electrostatic Potential of Specific Mineral Faces

    SciTech Connect

    Zarzycki, Piotr P.; Chatman, Shawn ME; Preocanin, Tajana; Rosso, Kevin M.

    2011-07-05

    Reaction rates of environmental processes occurring at hydrated mineral surfaces are primarily controlled by the electrostatic potential that develops at the interface. This potential depends on the structure of exposed crystal faces, as well as the pH and the type of ions and their interactions with these faces. Despite its importance, experimental methods for determining fundamental electrostatic properties of specific crystal faces such as the point of zero charge are few. Here we show that this information may be obtained from simple, cyclic potentiometric titration using a well characterized single-crystal electrode exposing the face of interest. The method exploits the presence of a hysteresis loop in the titration measurements that allows extraction of key electrostatic descriptors using the Maxwell construction. The approach is demonstrated for hematite (α-Fe2O3) (001), and a thermodynamic proof is provided for the resulting estimate of its point of zero charge. Insight gained from this method will aid in predicting the fate of migrating contaminants, mineral growth/dissolution processes, mineral-microbiological interactions, and in testing surface complexation theories.

  19. Iron oxyhydroxide mineralization on microbial extracellular polysaccharides

    SciTech Connect

    Chan, Clara S.; Fakra, Sirine C.; Edwards, David C.; Emerson, David; Banfield, Jillian F.

    2010-06-22

    Iron biominerals can form in neutral pH microaerophilic environments where microbes both catalyze iron oxidation and create polymers that localize mineral precipitation. In order to classify the microbial polymers that influence FeOOH mineralogy, we studied the organic and mineral components of biominerals using scanning transmission X-ray microscopy (STXM), micro X-ray fluorescence ({mu}XRF) microscopy, and high-resolution transmission electron microscopy (HRTEM). We focused on iron microbial mat samples from a creek and abandoned mine; these samples are dominated by iron oxyhydroxide-coated structures with sheath, stalk, and filament morphologies. In addition, we characterized the mineralized products of an iron-oxidizing, stalk-forming bacterial culture isolated from the mine. In both natural and cultured samples, microbial polymers were found to be acidic polysaccharides with carboxyl functional groups, strongly spatially correlated with iron oxyhydroxide distribution patterns. Organic fibrils collect FeOOH and control its recrystallization, in some cases resulting in oriented crystals with high aspect ratios. The impact of polymers is particularly pronounced as the materials age. Synthesis experiments designed to mimic the biomineralization processes show that the polysaccharide carboxyl groups bind dissolved iron strongly but release it as mineralization proceeds. Our results suggest that carboxyl groups of acidic polysaccharides are produced by different microorganisms to create a wide range of iron oxyhydroxide biomineral structures. The intimate and potentially long-term association controls the crystal growth, phase, and reactivity of iron oxyhydroxide nanoparticles in natural systems.

  20. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Prospecting, mineral locations, mineral 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...

  1. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Prospecting, mineral locations, mineral 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...

  2. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Prospecting, mineral locations, mineral 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...

  3. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Prospecting, mineral locations, mineral 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...

  4. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Prospecting, mineral locations, mineral 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...

  5. Estimation of palaeohydrochemical conditions using carbonate minerals

    NASA Astrophysics Data System (ADS)

    Amamiya, H.; Mizuno, T.; Iwatsuki, T.; Yuguchi, T.; Murakami, H.; Saito-Kokubu, Y.

    2014-12-01

    The long-term evolution of geochemical environment in deep underground is indispensable research subject for geological disposal of high-level radioactive waste, because the evolution of geochemical environment would impact migration behavior of radionuclides in deep underground. Many researchers have made efforts previously to elucidate the geochemical environment within the groundwater residence time based on the analysis of the actual groundwater. However, it is impossible to estimate the geochemical environment for the longer time scale than the groundwater residence time in this method. In this case, analysis of the chemical properties of secondary minerals are one of useful method to estimate the paleohydrochemical conditions (temperature, salinity, pH and redox potential). In particular, carbonate minerals would be available to infer the long-term evolution of hydrochemical for the following reasons; -it easily reaches chemical equilibrium with groundwater and precipitates in open space of water flowing path -it reflects the chemical and isotopic composition of groundwater at the time of crystallization We reviewed the previous studies on carbonate minerals and geochemical conditions in deep underground and estimated the hydrochemical characteristics of past groundwater by using carbonate minerals. As a result, it was found that temperature and salinity of the groundwater during crystallization of carbonate minerals were evaluated quantitatively. On the other hand, pH and redox potential can only be understood qualitatively. However, it is suggested that the content of heavy metal elements such as manganese, iron and uranium, and rare earth elements in the carbonate minerals are useful indicators for estimating redox potential. This study was carried out under a contract with METI (Ministry of Economy, Trade and Industry) as part of its R&D supporting program for developing geological disposal technology.

  6. Mineral chemical study of U-bearing minerals from the Dominion Reefs, South Africa

    NASA Astrophysics Data System (ADS)

    Rantzsch, Ulrike; Gauert, Christoph D. K.; van der Westhuizen, Willem A.; Duhamel, Isabelle; Cuney, Michel; Beukes, Gerhard J.

    2011-02-01

    The Neo-Archean Dominion Reefs (~3.06 Ga) are thin meta-conglomerate layers with concentrations of U- and Th-bearing heavy minerals higher than in the overlying Witwatersrand Reefs. Ore samples from Uranium One Africa's Rietkuil and Dominion exploration areas near Klerksdorp, South Africa, were investigated for their mineral paragenesis, texture and mineral chemical composition. The ore and heavy mineral assemblages consist of uraninite, other uraniferous minerals, Fe sulphides, Ni-Co sulfarsenides, garnet, pyrite, pyrrhotite, monazite, zircon, chromite, magnetite and minor gold. Sub-rounded uraninite grains occur associated with the primary detrital heavy mineral paragenesis. U-Ti, U-Th minerals, pitchblende (colloform uraninite) and coffinite are of secondary, re-mobilised origin as evidenced by crystal shape and texture. Most of the uranium mineralisation is represented by detrital uraninite with up to 70.2 wt.% UO2 and up to 9.3 wt.% ThO2. Re-crystallised phases such as secondary pitchblende (without Th), coffinite, U-Ti and U-Th phases are related to hydrothermal overprint during low-grade metamorphism and are of minor abundance.

  7. Reagan issues mineral policy

    NASA Astrophysics Data System (ADS)

    The National Materials and Minerals Program plan and report that President Reagan sent to Congress on April 5 aims to ‘decrease America's minerals vulnerability’ while reducing future dependence on potentially unstable foreign sources of minerals. These goals would be accomplished by taking inventory of federal lands to determine mineral potential; by meeting the stockpile goals set by the Strategic and Critical Material Stockpiling Act; and by establishing a business and political climate that would encourage private-sector research and development on minerals.Now that the Administration has issued its plan, the Subcommittee on Mines and Mining of the House Committee on Interior and Insular Affairs will consider the National Minerals Security Act (NMSA), which was introduced 1 year ago by subcommittee chairman Jim Santini (D-Nev.) [Eos, May 19, 1981, p. 497]. The bill calls for establishing a three-member White-House-level council to coordinate the development of a national minerals policy; amending tax laws to assist the mining industry to make capital investments to locate and produce strategic materials; and creating a revolving fund for the sale and purchase of strategic minerals. In addition, the NMSA bill would allow the secretary of the interior to make previously withdrawn public lands available for mineral development. The subcommittee will hold a hearing on the Administration's plan on May 11. Interior Secretary James Watt has been invited to testify.

  8. Mineral Processing Sector

    EPA Pesticide Factsheets

    Find environmental regulatory and compliance information for the nonmetallic mineral processing sector (NAICS 327), including NESHAPs for asbestos and hazardous waste, and wastewater permit information.

  9. Alkali metal and rare earth element evolution of rock-forming minerals from the Gatumba area pegmatites (Rwanda): Quantitative assessment of crystal-melt fractionation in the regional zonation of pegmatite groups

    NASA Astrophysics Data System (ADS)

    Hulsbosch, Niels; Hertogen, Jan; Dewaele, Stijn; André, Luc; Muchez, Philippe

    2014-05-01

    This study presents a general model for the evaluation of Rayleigh fractional crystallisation as the principal differentiation mechanism in the formation of regionally zoned common and rare-element pegmatites. The magmatic evolution of these systems from a granitic source is reconstructed by means of alkali element and rare earth element (REE) analyses of rock-forming minerals (feldspars, micas and tourmaline), which represent a whole sequence of regional pegmatite zonation. The Gatumba pegmatite field (Rwanda, Central Africa) is chosen as case study area because of its well-developed regional zonation sequence. The pegmatites are spatially and temporally related to peraluminous G4-granites (986 ± 10 Ma). The regional zonation is developed around a G4-granite and the proximal pegmatites grade outwardly into biotite, two-mica and muscovite pegmatites. Rare-element (Nb-Ta-Sn) pegmatites occur most distal from the granite.

  10. Apoferritin crystals

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Dr. Alexander Chernov, of the Universities Space Research Association (USRA) and based at Marshall Space Flight Center, is investigating why protein crystals grown in space are, in about 20 percent of cases, better-ordered than those grown on the ground. They are testing the idea that the amount of impurities trapped by space-grown crystals may be different than the amount trapped by crystals grown on Earth because convection is negligible in microgravity. The concentrations or impurities in many space-grown crystals turned out to be several times lower than that in the terrestrial ones, sometimes below the detection limit. The ground-based experiment also showed that the amount of impurities per unit volume of the crystals was usually higher than the amount per unit volume of the solution. This means that a growing crystal actually purifies the solution in its immediate vicinity. Here, an impurity depletion zone is created around apoferritin crystals grown in gel, imitating microgravity conditions.

  11. 36 CFR 293.14 - Mineral leases and mineral permits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Mineral leases and mineral... AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.14 Mineral leases and mineral permits. (a) All laws pertaining to mineral leasing shall extend to each National Forest Wilderness for the period specified in the...

  12. 36 CFR 293.14 - Mineral leases and mineral permits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Mineral leases and mineral... AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.14 Mineral leases and mineral permits. (a) All laws pertaining to mineral leasing shall extend to each National Forest Wilderness for the period specified in the...

  13. 36 CFR 293.14 - Mineral leases and mineral permits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Mineral leases and mineral... AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.14 Mineral leases and mineral permits. (a) All laws pertaining to mineral leasing shall extend to each National Forest Wilderness for the period specified in the...

  14. 36 CFR 293.14 - Mineral leases and mineral permits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Mineral leases and mineral... AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.14 Mineral leases and mineral permits. (a) All laws pertaining to mineral leasing shall extend to each National Forest Wilderness for the period specified in the...

  15. 36 CFR 293.14 - Mineral leases and mineral permits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Mineral leases and mineral... AGRICULTURE WILDERNESS-PRIMITIVE AREAS § 293.14 Mineral leases and mineral permits. (a) All laws pertaining to mineral leasing shall extend to each National Forest Wilderness for the period specified in the...

  16. Orfeo, the Pleiades Accompaniment Program and its Users Thematic Commissioning

    NASA Astrophysics Data System (ADS)

    Tinel, C.; Grizonnet, M.; Fontannaz, D.; de Boissezon, H.; Giros, A.

    2012-08-01

    ORFEO, the PLEIADES Accompaniment Program, was set up by CNES, the French Space Agency, to prepare, accompany and promote the use and the exploitation of the images acquired by this Very High Resolution optical sensor. It was initiated in 2004 and will last until the end of the first year of the satellite life (launched in December 2011) . The Thematic part of the ORFEO accompaniment program covers a large range of applications, and aims at specifying and validating products and services required by users. An in-depth work of user needs assessments in eight thematic domains (sea and coastline, risks and humanitarian aid, cartography and urban planning, geophysical hazards, hydrology, forestry, agriculture and defence) has given rise to a large number of feasibility studies from 2006 to 2011. The Methodological Part of the ORFEO accompaniment program aims at preparing the use and exploitation of these submetric images. CNES decided to develop Orfeo Toolbox (OTB), an open source library capitalising the methodological know-how as a set of image processing and algorithmic components. Among other, OTB provides a number of heavily documented image processing functionalities such as filtering, feature extraction, segmentation, classification, change detection, 3D extraction, GIS links,.... As a conclusion to the ORFEO program, the PLEIADES Users Thematic Commissioning (UTC) started three months after the satellite launch and will last until mid 2013. It covers a large number of specific interest ORFEO sites, on which PLEIADES images are being intensively acquired and processed. These ORFEO sites have been chosen according to the expectations expressed by the users in terms of their interest for dedicated thematic, their geographic location and their multi-thematic content. This paper presents the ORFEO program achievements (thematic and methodology) and the organisation of the Users Thematic Commissioning (sites, studies). The paper is illustrated with some examples of

  17. ENCEPHALOMYELITIS ACCOMPANIED BY MYELIN DESTRUCTION EXPERIMENTALLY PRODUCED IN MONKEYS

    PubMed Central

    Rivers, Thomas M.; Schwentker, Francis F.

    1935-01-01

    The repeated intramuscular injections of aqueous emulsions and alcohol-ether extracts of sterile normal rabbit brains in some manner produced pathological changes accompanied by myelin destruction in the brains of 7 of 8 monkeys (Macacus rhesus). Eight, control monkeys remained well. Cultures from the involved brains remained sterile, and no transmissible agent was demonstrated by means of intracerebral inoculations of emulsions of bits of the brains into monkeys, rabbits, guinea pigs, and white mice. PMID:19870385

  18. Mineral Fiber Toxicology

    EPA Science Inventory

    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...

  19. Digging into Minnesota Minerals.

    ERIC Educational Resources Information Center

    Minnesota State Dept. of Natural Resources, St. Paul.

    This publication presents students with facts about geology and several learning activities. Topics covered include rocks and minerals, volcanoes and earthquakes, fossils, exploration geology, mining in Minnesota, environmental issues related to mining, mineral uses, mining history, and the geology of Minnesota's state parks. A geologic timetable…

  20. Mineral physics abroad

    NASA Astrophysics Data System (ADS)

    Liebermann, Robert

    During the 1983-1984 academic year, I spent a sabbatical leave in France, during which I had the opportunity to visit several mineral physics laboratories in Europe and meet many of our colleagues there. The purpose of this item is to report briefly on developments of interest to the U.S. mineral physics community.

  1. Mineral commodity summaries 2016

    USGS Publications Warehouse

    Ober, Joyce A.

    2016-01-01

    This report is the earliest Government publication to furnish estimates covering 2015 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

  2. Vitamins, Minerals, and Mood

    ERIC Educational Resources Information Center

    Kaplan, Bonnie J.; Crawford, Susan G.; Field, Catherine J.; Simpson, J. Steven A.

    2007-01-01

    In this article, the authors explore the breadth and depth of published research linking dietary vitamins and minerals (micronutrients) to mood. Since the 1920s, there have been many studies on individual vitamins (especially B vitamins and Vitamins C, D, and E), minerals (calcium, chromium, iron, magnesium, zinc, and selenium), and vitamin-like…

  3. Mineral Wool Insulation Binders

    NASA Astrophysics Data System (ADS)

    Kowatsch, Stefan

    Mineral wool is considered the best known insulation type among the wide variety of insulation materials. There are three types of mineral wool, and these consist of glass, stone (rock), and slag wool. The overall manufacturing processes, along with features such as specifications and characteristics for each of these types, as well as the role of the binder within the process are described.

  4. Mineral Commodity Summaries 2002

    USGS Publications Warehouse

    ,

    2002-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  5. Mineral Commodity Summaries 2005

    USGS Publications Warehouse

    ,

    2005-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  6. Mineral Commodity Summaries 2001

    USGS Publications Warehouse

    ,

    2001-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  7. Mineral Commodity Summaries 2007

    USGS Publications Warehouse

    ,

    2007-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  8. Mineral Commodity Summaries 2006

    USGS Publications Warehouse

    ,

    2006-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  9. Mineral Commodity Summaries 1998

    USGS Publications Warehouse

    ,

    1998-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  10. Mineral Commodity Summaries 1997

    USGS Publications Warehouse

    ,

    1997-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials

  11. Mineral Commodity Summaries 1999

    USGS Publications Warehouse

    ,

    1999-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  12. Mineral Commodity Summaries 2003

    USGS Publications Warehouse

    ,

    2003-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  13. Mineral Commodity Summaries 2004

    USGS Publications Warehouse

    ,

    2004-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  14. Mineral Commodity Summaries 2000

    USGS Publications Warehouse

    ,

    2000-01-01

    Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

  15. Mineral commodity summaries 2017

    USGS Publications Warehouse

    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.

  16. Mineral Commodity Summaries 2011

    USGS Publications Warehouse

    ,

    2011-01-01

    Each chapter of the 2011 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2010 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses. For mineral commodities for which there is a Government stockpile, detailed information concerning the stockpile status is included in the two-page synopsis. Mineral Commodity Summaries 2011 contains new chapters on iron oxide pigments, wollastonite, and zeolites. The chapters on mica (natural), scrap and flake and mica (natural), sheet have been combined into a single chapter - mica (natural). Abbreviations and units of measure, and definitions of selected terms used in the report, are in Appendix A and Appendix B, respectively. "Appendix C - Reserves and Resources" has been divided into "Part A - Resource/Reserve Classification for Minerals" and "Part B - Sources of Reserves Data," including some information that was previously in this introduction. 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 2011 are welcomed.

  17. Lysozyme Crystal

    NASA Technical Reports Server (NTRS)

    2004-01-01

    To the crystallographer, this may not be a diamond but it is just as priceless. A Lysozyme crystal grown in orbit looks great under a microscope, but the real test is X-ray crystallography. The colors are caused by polarizing filters. Proteins can form crystals generated by rows and columns of molecules that form up like soldiers on a parade ground. Shining X-rays through a crystal will produce a pattern of dots that can be decoded to reveal the arrangement of the atoms in the molecules making up the crystal. Like the troops in formation, uniformity and order are everything in X-ray crystallography. X-rays have much shorter wavelengths than visible light, so the best looking crystals under the microscope won't necessarily pass muster under the X-rays. In order to have crystals to use for X-ray diffraction studies, crystals need to be fairly large and well ordered. Scientists also need lots of crystals since exposure to air, the process of X-raying them, and other factors destroy them. Growing protein crystals in space has yielded striking results. Lysozyme's structure is well known and it has become a standard in many crystallization studies on Earth and in space.

  18. Young drivers' attitudes toward accompanied driving: a new multidimensional measure.

    PubMed

    Taubman-Ben-Ari, Orit

    2010-07-01

    Four studies were conducted in order to develop and validate a multidimensional instrument to assess attitudes toward accompanied driving among young drivers. Study 1 (n=841) focused on developing the Attitudes Toward Accompanied Driving Scale (ATADS), a self-report scale based on five previously conceptualized domains of attitudes. Factor analysis revealed the five hypothesized factors: Tension, Relatedness, Disapproval, Avoidance, and Anxiety. In addition, significant associations were found between these factors and gender, age, and the assessment of reckless driving as risky. Study 2 (n=651) adopted a developmental approach, comparing the attitudes of participants in various stages of licensure. Disapproval and Tension were found to be higher, and Relatedness lower, among participants who had not yet begun driving instruction than among those who were taking driving lessons or had already obtained a license. Study 3 (n=160) revealed associations between the five ATADS factors and perceived driving costs and benefits. In Study 4 (n=193), associations were found between these factors and driver's self-image, with a combination of ATADS factors, self-image, and gender contributing to the explained variance of two outcome variables: driving self-efficacy, and reported frequency of reckless driving. The discussion focuses on the validity and utility of the new measure of young drivers' attitudes toward accompanied driving, stressing its practical implications for road safety.

  19. Real-time implementation of an interactive jazz accompaniment system

    NASA Astrophysics Data System (ADS)

    Deshpande, Nikhil

    Modern computational algorithms and digital signal processing (DSP) are able to combine with human performers without forced or predetermined structure in order to create dynamic and real-time accompaniment systems. With modern computing power and intelligent algorithm layout and design, it is possible to achieve more detailed auditory analysis of live music. Using this information, computer code can follow and predict how a human's musical performance evolves, and use this to react in a musical manner. This project builds a real-time accompaniment system to perform together with live musicians, with a focus on live jazz performance and improvisation. The system utilizes a new polyphonic pitch detector and embeds it in an Ableton Live system - combined with Max for Live - to perform elements of audio analysis, generation, and triggering. The system also relies on tension curves and information rate calculations from the Creative Artificially Intuitive and Reasoning Agent (CAIRA) system to help understand and predict human improvisation. These metrics are vital to the core system and allow for extrapolated audio analysis. The system is able to react dynamically to a human performer, and can successfully accompany the human as an entire rhythm section.

  20. Bulk modulus for polar covalent crystals

    PubMed Central

    Xu, Bo; Wang, Qianqian; Tian, Yongjun

    2013-01-01

    A microscopic empirical model of bulk modulus based on atomic-scale parameters is proposed. These parameters include the bond length, the effective bonded valence electron (EBVE) number, and the coordination number product of two bonded atoms, etc. The estimated bulk moduli from our model are in good agreement with experimental values for various polar covalent crystals including ionic crystals. Our current work sheds lights on the nature of bulk modulus, provides useful clues for design of crystals with low compressibility, and is applicable to complex crystals such as minerals of geophysical importance. PMID:24166098

  1. Underground mineral extraction

    NASA Technical Reports Server (NTRS)

    Miller, C. G.; Stephens, J. B.

    1980-01-01

    A method was developed for extracting underground minerals such as coal, which avoids the need for sending personnel underground and which enables the mining of steeply pitched seams of the mineral. The method includes the use of a narrow vehicle which moves underground along the mineral seam and which is connected by pipes or hoses to water pumps at the surface of the Earth. The vehicle hydraulically drills pilot holes during its entrances into the seam, and then directs sideward jets at the seam during its withdrawal from each pilot hole to comminute the mineral surrounding the pilot hole and combine it with water into a slurry, so that the slurried mineral can flow to a location where a pump raises the slurry to the surface.

  2. The organic-mineral interaction in mollusk shell

    NASA Astrophysics Data System (ADS)

    Metzler, Rebecca A.

    Macromolecules are a minority but important component of the minerals formed by living organisms, or biominerals. While many proteins from the nacre and prismatic layers of mollusk shells have been identified and sequenced, the molecular interaction, organization, and rearrangements of proteins upon organic-mineral bond formation, and the effect of this interaction on crystal formation, deformation, and orientation are poorly understood. To examine the organic-mineral interaction in mollusk shells, we prepared model systems consisting of calcium carbonate grown in the presence of synthetic mollusk shell polypeptides. X-ray absorption near-edge structure (XANES) spectroscopy and x-ray photoelectron emission microscopy (X-PEEM) were used to examine the electronic structure and bonding environment of both the surface and bulk of model biomineral crystals, thereby determining that the organic-mineral interaction is a series of events starting with bond formation and ending with the fully formed mineral. XANES spectra acquired from the model biomineral systems showed that upon organic-mineral bond formation both the crystal and the polypeptides exhibit bond and molecular structure alterations. We acquired XANES spectra from the surface of calcium carbonate crystals grown in the presence of six synthetic polypeptides sequenced after mollusk nacre proteins: AP7N, AP24N, N16N, asp1, asp2, and ACCN. All of these model biominerals gave similar results, namely the disruption of CO bonds in calcite and enhancement of the peaks associated with C-H bonds bonds in peptides, indicating disordering of the calcite crystal and ordering of the peptides upon binding. We also show that these changes do not occur when the acidic amino acids, Asp and Glu, are replaced in the N16N sequence with Asn and Gln, respectively, demonstrating the importance of carboxyl groups in organic-mineral bond formation. We examined the bulk crystal structure of crystals grown in the presence of N16N and asp

  3. Single-Crystal Elasticity of Earth Materials: An Appraisal

    NASA Astrophysics Data System (ADS)

    Duffy, T. S.

    2015-12-01

    The elastic properties of minerals are of central importance for interpreting seismic data for the Earth's crust, mantle, and core. Mineral elasticity data also have more general applications towards understanding equations of state, phase equilibria, interatomic forces, material strength, and phase transitions. The singe-crystal elastic properties are the most generally useful as they provide complete information on the anisotropy of elastic moduli (e.g. Poisson's ratio, Young's modulus), sound velocities, and compressibility. Measurement of the full set of single-crystal elastic properties remains challenging especially for lower symmetry crystals. In this talk, I present an overview of our current understanding of single-crystal elasticity based on a newly constructed database of single-crystal elastic properties. At ambient conditions the full elastic tensor of about 150 minerals have now been measured, along with about another 60 related compounds that are not formally minerals. About two-thirds of the measured minerals are oxides or silicates. A limitation of the existing database is that only about 10% of the measurements are on crystals of monoclinic or triclinic symmetry, while these two systems account for about 40% of known minerals. Additionally, only a smaller subset of minerals have been examined at high pressure or temperature conditions. Several applications of the database will be presented emphasizing trends in elastic anisotropy. The pyroxenes will be used as an illustrative example.

  4. RNA Crystallization

    NASA Technical Reports Server (NTRS)

    Golden, Barbara L.; Kundrot, Craig E.

    2003-01-01

    RNA molecules may be crystallized using variations of the methods developed for protein crystallography. As the technology has become available to syntheisize and purify RNA molecules in the quantities and with the quality that is required for crystallography, the field of RNA structure has exploded. The first consideration when crystallizing an RNA is the sequence, which may be varied in a rational way to enhance crystallizability or prevent formation of alternate structures. Once a sequence has been designed, the RNA may be synthesized chemically by solid-state synthesis, or it may be produced enzymatically using RNA polymerase and an appropriate DNA template. Purification of milligram quantities of RNA can be accomplished by HPLC or gel electrophoresis. As with proteins, crystallization of RNA is usually accomplished by vapor diffusion techniques. There are several considerations that are either unique to RNA crystallization or more important for RNA crystallization. Techniques for design, synthesis, purification, and crystallization of RNAs will be reviewed here.

  5. Physical properties of evaporite minerals

    USGS Publications Warehouse

    Robertson, Eugene C.

    1962-01-01

    The data in the following tables were abstracted from measurements of physical properties of evaporite minerals or of equivalent synthetic compounds. The compounds considered are the halide and sulfate salts which supposedly precipitated from evaporating ocean water and which form very extensive and thick "rock salt" beds. These beds are composed almost entirely of NaCl. In places where the beds are deeply buried and where fractures occur in the overlying rocks, the salt is plastically extruded upward as in a pipe to form the "salt domes". Most of the tables are for NaCl, both the natural (halite) and the synthetic salt, polycrystalline and single crystals. These measurements have been collected for use 1) in studies on storage of radioactive wastes in salt domes or beds, 2) in calculations concerned with nuclear tests in salt domes and beds, and 3) in studies of phenomena in salt of geologic interest. Rather than an exhaustive compilation of physical property measurements, there tables represent a summary of data from accessible sources. As limitations of time have presented making a more systematic and comprehensive selection, the data given may seem arbitrarily chosen. Some of the data listed are old, and newer, more accurate data are undoubtedly available. Halite (an synthetic NaCl) has been very thoroughly studied because of its relatively simple and highly symmetrical crystal structure, its easy availability naturally or synthetically, both in single crystals and polycrystalline, its useful and scientifically interesting properties, and its role as a compound of almost purely ionic bonding. The measurements of NaCl in the tables, however, represent only a small part of the total number of observations; discrimination was necessary to keep the size of the tabulations manageable. The physical properties of the evaporite minerals other than halite and sylvite have received only desultory attention of experiementalists, and appear in only a few tables. The

  6. Minerals yearbook, 1993. Volume 1. Metals and minerals. Annual report

    SciTech Connect

    1993-12-31

    This edition of the Mineral Yearbook discusses the performance of the worlwide minerals and materials industry during 1993 and provides background information to assist in interpreting that performance. Volume 1, Metals and Minerals, contains chapters on virtually all metallic and industrial mineral commodities important to the U.S. economy. A chapter on survey methods with a statistical summary of nonfuel minerals, and a chapters on trends in mining and quarrying in the metals and industrial mineral industries are also included.

  7. Minerals Yearbook, centennial edition 1981. Volume I. Metals and minerals

    SciTech Connect

    Not Available

    1983-01-01

    This edition of the Minerals Yearbook Marks the centennial of the first annual publication of comprehensive mineral industry statistics by the Federal Government. This volume of the Minerals Yearbook, covering metals and minerals, contains 71 commodity or commodity group chapters with data on approximately 90 minerals that were obtained as a result of the mineral information gathering activities of the Bureau of Mines. In addition, the volume contains a chapter on mining and quarrying trends and a statistical summary.

  8. Some physicochemical aspects of water-soluble mineral flotation.

    PubMed

    Wu, Zhijian; Wang, Xuming; Liu, Haining; Zhang, Huifang; Miller, Jan D

    2016-09-01

    Some physicochemical aspects of water-soluble mineral flotation including hydration phenomena, associations and interactions between collectors, air bubbles, and water-soluble mineral particles are presented. Flotation carried out in saturated salt solutions, and a wide range of collector concentrations for effective flotation of different salts are two basic aspects of water-soluble mineral flotation. Hydration of salt ions, mineral particle surfaces, collector molecules or ions, and collector aggregates play an important role in water-soluble mineral flotation. The adsorption of collectors onto bubble surfaces is suggested to be the precondition for the association of mineral particles with bubbles. The association of collectors with water-soluble minerals is a complicated process, which may include the adsorption of collector molecules or ions onto such surfaces, and/or the attachment of collector precipitates or crystals onto the mineral surfaces. The interactions between the collectors and the minerals include electrostatic and hydrophobic interactions, hydrogen bonding, and specific interactions, with electrostatic and hydrophobic interactions being the common mechanisms. For the association of ionic collectors with minerals with an opposite charge, electrostatic and hydrophobic interactions could have a synergistic effect, with the hydrophobic interactions between the hydrophobic groups of the previously associated collectors and the hydrophobic groups of oncoming collectors being an important attractive force. Association between solid particles and air bubbles is the key to froth flotation, which is affected by hydrophobicity of the mineral particle surfaces, surface charges of mineral particles and bubbles, mineral particle size and shape, temperature, bubble size, etc. The use of a collector together with a frother and the use of mixed surfactants as collectors are suggested to improve flotation.

  9. Computational crystallization.

    PubMed

    Altan, Irem; Charbonneau, Patrick; Snell, Edward H

    2016-07-15

    Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed.

  10. Mineral facilities of Europe

    USGS Publications Warehouse

    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.

  11. Elasticity of Hydrous Aluminosilicate Mineral, Topaz-OH (Al2SiO4(OH)2) at High Pressures

    NASA Astrophysics Data System (ADS)

    Hariharan, A.; Mookherjee, M.; Tsuchiya, J.

    2015-12-01

    We examined the equation of state and high-pressure elasticity of the hydrous aluminosilicate mineral topaz-OH (Al2SiO4(OH)2) using first principles simulation. Topaz-OH is a hydrous phase in the Al2O3-SiO2-H2O (ASH) ternary system, which is relevant for the mineral phase relations in the hydrated sedimentary layer of subducting slabs. Based on recent experiments, it is known that the protons in the topaz-OH exhibit positional disorder with half occupancy over two distinct crystallographic sites. In order to adequately depict the proton environment in the topaz-OH, we examined five crystal structure models with distinct configuration for the protons. Upon full geometry optimization, we find that there are two distinct crystal structures for the topaz-OH. The first crystal structure has an orthorhombic Pbnm space group symmetry, and the second crystal structure has a monoclinic P21/c space group symmetry. At static conditions, the monoclinic (P21/c) topaz-OH has lower energy compared to the orthorhombic (Pbnm) topaz-OH. The energy of the monoclinic (P21/c) topaz-OH remains stable at least up to 40 GPa, i.e., pressures beyond the thermodynamic stability of the topaz-OH. Based on the results from first principles simulation, the equation of state for the monoclinic topaz-OH is well represented by a third-order Birch-Murnaghan formulation, with V0 = 348.63 (±0.04) Å3, K0 = 164.7 (±0.04) GPa, and K'0 = 4.24 (±0.05). The equation of state for the orthorhombic topaz-OH is well represented by a third-order Birch-Murnaghan formulation, with V0 = 352.47 (±0.04) Å3, K0 = 166.4 (±0.06) GPa, and K'0 = 4.03 (±0.04). While the bulk modulus is very similar for both the monoclinic and orthorhombic topaz-OH, the shear elastic moduli are very sensitive to the position of the proton and the orientation of the hydroxyl (O-H) groups. In the hydrated sedimentary layer of a subducting slab, transformation of a mineral assemblage consisting of coesite (SiO2) and diaspore (AlOOH) to

  12. Mineral homeostasis and regulation of mineralization processes in the skeletons of sharks, rays and relatives (Elasmobranchii).

    PubMed

    Dean, Mason N; Ekstrom, Laura; Monsonego-Ornan, Efrat; Ballantyne, Jim; Witten, P Eckhard; Riley, Cyrena; Habraken, Wouter; Omelon, Sidney

    2015-10-01

    Sharks, rays and other elasmobranch fishes are characterized by a skeletal type that is unique among living vertebrates, comprised predominantly of an unmineralized cartilage, covered by a thin outer layer of sub-millimeter, mineralized tiles called tesserae. The mineralized portion of the skeleton appears to grow only by apposition, adding material at the edges of each tessera; maintenance of non-mineralized joints between tesserae is therefore vital, with precise control of mineral deposition and inhibition at the many thousands of growth fronts in the skeleton. Yet, we have only scattered evidence as to how the elasmobranchs mineralize and grow their skeletons. In this review, we take an "environment to skeleton" approach, drawing together research from a vast range of perspectives to track calcium and phosphate from the typical elasmobranch habitats into and through the body, to their deposition at tesseral growth fronts. In the process, we discuss the available evidence for skeletal resorption capability, mineral homeostasis hormones, and nucleation inhibition mechanisms. We also outline relevant theories in crystal nucleation and typical errors in measurements of serum calcium and phosphate in the study of vertebrate biology. We assemble research that suggests consensus in some concepts in elasmobranch skeletal development, but also highlight the very large gaps in our knowledge, particularly in regards to endocrine functional networks and biomineralization mechanisms. In this way, we lay out frameworks for future directions in the study of elasmobranch skeletal biology with stronger and more comparative links to research in other disciplines and into other taxa.

  13. Molecular mechanics of mineralized collagen fibrils in bone

    NASA Astrophysics Data System (ADS)

    Nair, Arun K.; Gautieri, Alfonso; Chang, Shu-Wei; Buehler, Markus J.

    2013-04-01

    Bone is a natural composite of collagen protein and the mineral hydroxyapatite. The structure of bone is known to be important to its load-bearing characteristics, but relatively little is known about this structure or the mechanism that govern deformation at the molecular scale. Here we perform full-atomistic calculations of the three-dimensional molecular structure of a mineralized collagen protein matrix to try to better understand its mechanical characteristics under tensile loading at various mineral densities. We find that as the mineral density increases, the tensile modulus of the network increases monotonically and well beyond that of pure collagen fibrils. Our results suggest that the mineral crystals within this network bears up to four times the stress of the collagen fibrils, whereas the collagen is predominantly responsible for the material’s deformation response. These findings reveal the mechanism by which bone is able to achieve superior energy dissipation and fracture resistance characteristics beyond its individual constituents.

  14. Immunomodulatory activity accompanying chicken egg yolk immunoglobulin Y.

    PubMed

    Polanowski, A; Zabłocka, A; Sosnowska, A; Janusz, M; Trziszka, T

    2012-12-01

    Immunity transfer from a mother to the newborn does not depend exclusively on immunoglobulins. Peptides, which are characterized by immunoregulatory properties that accompany IgG(2), known as proline-rich polypeptide complex (PRP), have been discovered for the first time in ovine colostrum. In this report we present new data showing that some immunoregulatory peptides associated with the main immunoglobulin class, IgY, are also present in the avian immune system. Cytokine-inducing activity of particular fractions obtained from ovine colostrum, IgG+ (IgG(2) containing PRP), IgG- (IgG(2) free of PRP), and purified PRP, was compared with that of crude egg yolk IgY (IgY+), additionally purified egg yolk IgY (IgY-), and polypeptides accompanying IgY named Yolkin (Y), using an ex vivo model of whole human blood cells. It was shown that both IgG+ fraction and PRP, but not IgG-, stimulated the whole blood cells to release tumor necrosis factor-α and interleukin-1β cytokines. Similar experiments performed with hen's egg IgY preparations showed that IgY+ and Y samples showed higher cytokine-inducing activity than samples additionally purified with the use of size exclusion chromatography (IgY-). The IgY+ at a dose of 100 μg was even more active than the positive lipopolysaccharide control. It was also found that Y is able to stimulate macrophage cell line J774.2 to release nitric oxide. The results obtained suggest that IgY, the main chicken immunoglobulin fraction, is accompanied by additional polypeptides and plays a role of a transporter of biologically active substances, which was observed in the case of colostral IgG.

  15. Minerals Management Service: Strategic plan

    SciTech Connect

    1997-09-30

    This plan addresses the management of the mineral resources on the Outer Continental Shelf in an environmentally sound and safe manner and the timely collection, verification, and distribution of mineral revenues from Federal and Indian lands. The Minerals Management Service (MMS) manages the Nation`s natural gas, oil and other mineral resources on the Outer Continental Shelf (OCS), and collects, accounts for, and disburses revenues from offshore federal mineral leases and from onshore mineral leases on Federal and Indian lands.

  16. Persistent Postconcussive Symptoms Are Accompanied by Decreased Functional Brain Oxygenation.

    PubMed

    Helmich, Ingo; Saluja, Rajeet S; Lausberg, Hedda; Kempe, Mathias; Furley, Philip; Berger, Alisa; Chen, Jen-Kai; Ptito, Alain

    2015-01-01

    Diagnostic methods are considered a major concern in the determination of mild traumatic brain injury. The authors examined brain oxygenation patterns in subjects with severe and minor persistent postconcussive difficulties and a healthy control group during working memory tasks in prefrontal brain regions using functional near-infrared spectroscopy. The results demonstrated decreased working memory performances among concussed subjects with severe postconcussive symptoms that were accompanied by decreased brain oxygenation patterns. An association appears to exist between decreased brain oxygenation, poor performance of working memory tasks, and increased symptom severity scores in subjects suffering from persistent postconcussive symptoms.

  17. Systemic lupus erythematosus accompanying with renal tuberculosis: a case report

    PubMed Central

    Li, Tao; Gao, Liang; Chen, Peng; Bu, Si-Yuan; Cao, De-Hong; Yang, Lu; Wei, Qiang

    2015-01-01

    A 26-year-old woman, with a six-year history of well-controlled systemic lupus erythematosus (SLE), complained of urinary frequency and urgency. After failure of commonly-used antibiotic therapy, mycobacterium tuberculosis was cultured from her urine and renal tuberculosis (TB) was diagnosed. However, she underwent right nephrectomy after the combination therapies of prednisone for SLE and anti-tuberculosis treatment for renal TB failed. To our knowledge, SLE accompanying renal TB is rare, and such a rapid deterioration in renal function has never been reported. PMID:26221395

  18. Seckel syndrome accompanied by semilobar holoprosencephaly and arthrogryposis.

    PubMed

    Sarici, Dilek; Akin, Mustafa Ali; Kara, Ahu; Doganay, Selim; Kurtoglu, Selim

    2012-03-01

    Seckel syndrome is a rare autosomal recessive disorder, and its characteristic features include prenatal and postnatal growth retardation, microcephaly, and "bird-like" face with prominent, beak-like nose and micrognathia. Additional abnormalities were described in the cardiovascular, hematopoietic, endocrine, and central nervous systems. We present the magnetic resonance imaging findings of a neonate with Seckel syndrome accompanied by semilobar holoprosencephaly and arthrogryposis. Major brain malformations may be associated with Seckel syndrome. Imaging studies should be performed to determine any central nervous system abnormalities. Considering the basic defect of neuroblast proliferation in Seckel syndrome, neuronal migration disorders should be sought in these patients.

  19. Vortex emission accompanies the advection of optical localized structures.

    PubMed

    Haudin, F; Rojas, R G; Bortolozzo, U; Clerc, M G; Residori, S

    2011-02-11

    We show that the advection of optical localized structures is accompanied by the emission of vortices, with phase singularities appearing in the wake of the drifting structure. Localized structures are obtained in a light-valve experiment and made to drift by a mirror tilt in the feedback loop. Pairs of oppositely charged vortices are detected for small drifts, whereas for large drifts a vortex array develops. Observations are supported by numerical simulations and linear stability analysis of the system equations and are expected to be generic for a large class of translated optical patterns.

  20. Polymer-mediated growth of crystals and mesocrystals.

    PubMed

    Cölfen, Helmut

    2013-01-01

    Polymers are important additives for the control of mineralization reactions in both biological and bioinspired mineralization. The reason is that they allow for a number of interactions with the growing crystals and even amorphous minerals. These can substantially influence the way the mineral grows on several levels. Already in the prenucleation phase, polymers can control the formation of prenucleation clusters and subsequently the nucleation event. Also, polymers can control whether the further crystallization follows a classical or nonclassical particle-mediated growth path. In this chapter, the main ways in which polymers can be used to control a crystallization reaction will be highlighted. In addition, polymers that are useful for this purpose and the experimental conditions suitable for directing a crystallization reaction into the desired direction through the use of polymers will be described.

  1. Crystal Data

    National Institute of Standards and Technology Data Gateway

    SRD 3 NIST Crystal Data (PC database for purchase)   NIST Crystal Data contains chemical, physical, and crystallographic information useful to characterize more than 237,671 inorganic and organic crystalline materials. The data include the standard cell parameters, cell volume, space group number and symbol, calculated density, chemical formula, chemical name, and classification by chemical type.

  2. Australian Mineral Foundation.

    ERIC Educational Resources Information Center

    Crowe, D. S.

    1980-01-01

    Provides details on the philosophy and operation of the Australian Mineral Foundation, established in 1970 to update professionals in the mining and petroleum industries. Services in continuing education courses and to secondary school teachers and students are described. (CS)

  3. Biological effects of minerals

    SciTech Connect

    Guthrie, G.D. Jr.

    1991-09-01

    In general, clay materials exhibit a range of biological activities, from apparently inactive or slightly active, such as hematite, to highly fibrogenic and carcinogenic, such as fibrous brucite (nemalite). The zeolites also exhibit such as range, with some mordenite being slightly active and erionite being highly active; however, erionite is the only zeolite that has been studied extensively. The diversity of mineral species holds great potential for probing these mechanisms, especially when mineralogical data are integrated with biological data. Unfortunately, many of the studies reporting data on the biological effects of clays and zeolites fail to report detailed mineralogical information; hence, it is difficult at present to interpret the biological activities of minerals in terms of their physical and chemical properties. Important mineralogical data that are only rarely considered in biological research include exact mineralogy of the specimen (i.e., identification and abundance of contaminants), physical and chemical properties of minerals, and surface properties of minerals. 141 refs., 1 fig., 8 tabs.

  4. Chitosan-Assisted Crystallization and Film Forming of Perovskite Crystals through Biomineralization.

    PubMed

    Yang, Yang; Sun, Chen; Yip, Hin-Lap; Sun, Runcang; Wang, Xiaohui

    2016-03-18

    Biomimetic mineralization is a powerful approach for the synthesis of advanced composite materials with hierarchical organization and controlled structure. Herein, chitosan was introduced into a perovskite precursor solution as a biopolymer additive to control the crystallization and to improve the morphology and film-forming properties of a perovskite film by way of biomineralization. The biopolymer additive was able to control the size and morphology of the perovskite crystals and helped to form smooth films. The mechanism of chitosan-mediated nucleation and growth of the perovskite crystals was explored. As a possible application, the chitosan-perovskite composite film was introduced into a planar heterojunction solar cell and increased power conversion efficiency relative to that observed for the pristine perovskite film was achieved. The biomimetic mineralization method proposed in this study provides an alternative way of preparing perovskite crystals with well-controlled morphology and properties and extends the applications of perovskite crystals in photoelectronic fields, including planar-heterojunction solar cells.

  5. Abrupt transition from fractional crystallization to magma mixing at Gorely volcano (Kamchatka) after caldera collapse

    NASA Astrophysics Data System (ADS)

    Gavrilenko, Maxim; Ozerov, Alexey; Kyle, Philip R.; Carr, Michael J.; Nikulin, Alex; Vidito, Christopher; Danyushevsky, Leonid

    2016-07-01

    A series of large caldera-forming eruptions (361-38 ka) transformed Gorely volcano, southern Kamchatka Peninsula, from a shield-type system dominated by fractional crystallization processes to a composite volcanic center, exhibiting geochemical evidence of magma mixing. Old Gorely, an early shield volcano (700-361 ka), was followed by Young Gorely eruptions. Calc-alkaline high magnesium basalt to rhyolite lavas have been erupted from Gorely volcano since the Pleistocene. Fractional crystallization dominated evolution of the Old Gorely magmas, whereas magma mixing is more prominent in the Young Gorely eruptive products. The role of recharge-evacuation processes in Gorely magma evolution is negligible (a closed magmatic system); however, crustal rock assimilation plays a significant role for the evolved magmas. Most Gorely magmas differentiate in a shallow magmatic system at pressures up to 300 MPa, ˜3 wt% H2O, and oxygen fugacity of ˜QFM + 1.5 log units. Magma temperatures of 1123-1218 °C were measured using aluminum distribution between olivine and spinel in Old and Young Gorely basalts. The crystallization sequence of major minerals for Old Gorely was as follows: olivine and spinel (Ol + Sp) for mafic compositions (more than 5 wt% of MgO); clinopyroxene and plagioclase crystallized at ˜5 wt% of MgO (Ol + Cpx + Plag) and magnetite at ˜3.5 wt% of MgO (Ol + Cpx + Plag + Mt). We show that the shallow magma chamber evolution of Old Gorely occurs under conditions of decompression and degassing. We find that the caldera-forming eruption(s) modified the magma plumbing geometry. This led to a change in the dominant magma evolution process from fractional crystallization to magma mixing. We further suggest that disruption of the magma chamber and accompanying change in differentiation process have the potential to transform a shield volcanic system to that of composite cone on a global scale.

  6. Fluorescent minerals, a review

    USGS Publications Warehouse

    Modreski, P.J.; Aumente-Modreski, R.

    1996-01-01

    Fluorescent minerals are more than just an attractive novelty, and collecting them is a speciality for thousands of individuals who appreciate their beauty, rarity, and scientific value. Fluorescent properties can be used as an aid to mineral identification, locality determination, and distinction between natural and synthetic gemstones. This article gives an overview of those aspects of fluorescence that are of most interest to collectors, hobbyists, and mineralogists. -from Authors

  7. [Synthetic mineral fibers].

    PubMed

    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 (< or = 3-3.5 microns) and the length of the fibres (< 100 microns), their biopersistence, which is much shorter for man-made mineral fibres than for asbestos fibres, their physicochemical structure and surface properties, and the exposure level. The chemical composition of the various types of man-made mineral fibres depends directly on the raw material used to manufacture them. While naturally occurring fibres are crystalline in structure, most man-made mineral fibres are amorphous silicates combined with various metal oxides and additives. Observations using intracavitary administration have provided evidence that some types of man-made mineral fibres are bioactive in cellular and animal experiments and may induce lung tumours and mesothelioma. It is difficult to extrapolate these results to humans since they bypass inhalation, deposition, clearance and translocation mechanisms. Inhalation studies show more realistic results but differences are observed between animal species regarding their sensibility to tumours. There is no firm evidence that exposure to various wools is associated with lung fibrosis, pleural lesions or nonspecific respiratory disease in humans. A possible exception may be mentioned for refractory 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

  8. Middleware Design for Swarm-Driving Robots Accompanying Humans.

    PubMed

    Kim, Min Su; Kim, Sang Hyuck; Kang, Soon Ju

    2017-02-17

    Research on robots that accompany humans is being continuously studied. The Pet-Bot provides walking-assistance and object-carrying services without any specific controls through interaction between the robot and the human in real time. However, with Pet-Bot, there is a limit to the number of robots a user can use. If this limit is overcome, the Pet-Bot can provide services in more areas. Therefore, in this study, we propose a swarm-driving middleware design adopting the concept of a swarm, which provides effective parallel movement to allow multiple human-accompanying robots to accomplish a common purpose. The functions of middleware divide into three parts: a sequence manager for swarm process, a messaging manager, and a relative-location identification manager. This middleware processes the sequence of swarm-process of robots in the swarm through message exchanging using radio frequency (RF) communication of an IEEE 802.15.4 MAC protocol and manages an infrared (IR) communication module identifying relative location with IR signal strength. The swarm in this study is composed of the master interacting with the user and the slaves having no interaction with the user. This composition is intended to control the overall swarm in synchronization with the user activity, which is difficult to predict. We evaluate the accuracy of the relative-location estimation using IR communication, the response time of the slaves to a change in user activity, and the time to organize a network according to the number of slaves.

  9. Bell's palsy: symptoms preceding and accompanying the facial paresis.

    PubMed

    De Seta, Daniele; Mancini, Patrizia; Minni, Antonio; Prosperini, Luca; De Seta, Elio; Attanasio, Giuseppe; Covelli, Edoardo; De Carlo, Andrea; Filipo, Roberto

    2014-01-01

    This individual prospective cohort study aims to report and analyze the symptoms preceding and accompanying the facial paresis in Bell's palsy (BP). Two hundred sixty-nine patients affected by BP with a maximum delay of 48 hours from the onset were enrolled in the study. The evolution of the facial paresis expressed as House-Brackmann grade in the first 10 days and its correlation with symptoms were analyzed. At the onset, 136 patients presented postauricular pain, 114 were affected by dry eye, and 94 reported dysgeusia. Dry mouth was present in 54 patients (19.7%), facial pain, hyperlacrimation, aural fullness, and hyperacusis represented a smaller percentage of the reported symptoms. After 10 days, 39.9% of the group had a severe paresis while 10.2% reached a complete recovery. Dry mouth at the onset was correlated with severe grade of palsy and was prognostic for poor recovery in the early period. These outcomes lead to the deduction that the nervus intermedius plays an important role in the presentation of the BP and it might be responsible for most of the accompanying symptomatology of the paresis. Our findings could be of important interest to early address a BP patient to further examinations and subsequent therapy.

  10. Bell's Palsy: Symptoms Preceding and Accompanying the Facial Paresis

    PubMed Central

    Mancini, Patrizia; Minni, Antonio; Prosperini, Luca; De Seta, Elio; Attanasio, Giuseppe; Covelli, Edoardo; De Carlo, Andrea; Filipo, Roberto

    2014-01-01

    This individual prospective cohort study aims to report and analyze the symptoms preceding and accompanying the facial paresis in Bell's palsy (BP). Two hundred sixty-nine patients affected by BP with a maximum delay of 48 hours from the onset were enrolled in the study. The evolution of the facial paresis expressed as House-Brackmann grade in the first 10 days and its correlation with symptoms were analyzed. At the onset, 136 patients presented postauricular pain, 114 were affected by dry eye, and 94 reported dysgeusia. Dry mouth was present in 54 patients (19.7%), facial pain, hyperlacrimation, aural fullness, and hyperacusis represented a smaller percentage of the reported symptoms. After 10 days, 39.9% of the group had a severe paresis while 10.2% reached a complete recovery. Dry mouth at the onset was correlated with severe grade of palsy and was prognostic for poor recovery in the early period. These outcomes lead to the deduction that the nervus intermedius plays an important role in the presentation of the BP and it might be responsible for most of the accompanying symptomatology of the paresis. Our findings could be of important interest to early address a BP patient to further examinations and subsequent therapy. PMID:25544960

  11. Biomineralization of magnetic minerals

    NASA Astrophysics Data System (ADS)

    Moskowitz, Bruce M.

    1995-07-01

    New developments and discoveries in biomineralization have occurred almost continuously in the intervening decade since the previous IUGG quadrennial report on biomineralization and biomagnetism was published [Kirschvink, 1983]. Biomineralization is widespread in the biosphere and over 60 different inorganic minerals are produced by a variety of organisms from bacteria to humans [Lowenstam and Weiner, 1989]. The literature on biomineralization is interdisplinary, combining research in microbiology, biotechnology, physics, geology, and paleomagnetism. For paleomagnetism and rock magnetism, iron biomineralization of magnetic minerals is of prime importance. From a paleomagnetism perspective, biogenic magnetic minerals can be deposited in sediments and acquire a natural remanent magnetization that preserves a record of the ancient geomagnetic field. From a rock magnetism perspective, biogenic magnetic minerals provide novel sources of magnetic material for experimental studies in fine particle magnetism. Both perspectives are interrelated through a common goal of developing magnetic techniques to detect biogenic magnetic minerals in sediments and soils. For example, the extent to which iron biominerals contribute to the fine-grained magnetic mineral assemblages in freshwater and marine sediments is important for identifying and interpreting the magnetic record of environmental change [Oldfield, 1992; Reynolds and King, this issue].

  12. Mineral commodity summaries 2014

    USGS Publications Warehouse

    ,

    2014-01-01

    Each chapter of the 2014 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2013 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses. For mineral commodities for which there is a Government stockpile, detailed information concerning the stockpile status is included in the two-page synopsis. Abbreviations and units of measure, and definitions of selected terms used in the report, are in Appendix A and Appendix B, respectively. “Appendix C—Reserves and Resources” includes “Part A—Resource/Reserve Classification for Minerals” and “Part B—Sources of Reserves Data.” 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 2014 are welcomed.

  13. Mineral commodity summaries 2013

    USGS Publications Warehouse

    ,

    2013-01-01

    Each chapter of the 2013 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2012 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses. For mineral commodities for which there is a Government stockpile, detailed information concerning the stockpile status is included in the two-page synopsis. Abbreviations and units of measure, and definitions of selected terms used in the report, are in Appendix A and Appendix B, respectively. “Appendix C—Reserves and Resources” includes “Part A—Resource/Reserve Classification for Minerals” and “Part B—Sources of Reserves Data.” 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 2013 are welcomed.

  14. Minerals: the resource gap

    SciTech Connect

    Velocci, T.

    1980-10-01

    US imports of important non-fuel minerals may have contributed to a false sense of security that could have serious economic and defense consequences. Imports account for over 90 percent of the chromite, manganese ore, and cobalt, and 90 percent of the platinum group metals. The primary sources for many of these minerals are the Soviet Union and Africa, a price and supply vulnerability which rivals Middle East oil and of which the American public is unaware. The Soviet shift to a net minerals importer will intensify competition for minerals and could lead to confrontation. The decline in US mineral production is blamed on escalating costs, largely from regulations, that prevent plant and equipment modernization and land withdrawal policies. A strategic stockpile planned for over 90 materials was established in 1939 for defense purposes, but eratic goals and planning as well as economic changes have kept the plan from being implemented. The first steps of an appropriate policy would promote domestic minerals production and open up Federal lands for exploration and development. (DCK)

  15. The nanophase iron mineral(s) in Mars soil

    NASA Technical Reports Server (NTRS)

    Banin, A.; Ben-Shlomo, T.; Margulies, L.; Blake, D. F.; Mancinelli, R. L.; Gehring, A. U.

    1993-01-01

    A series of surface-modified clays containing nanophase (np) iron oxide/oxyhydroxides of extremely small particle sizes, with total iron contents as high as found in Mars soil, were prepared by iron deposition on the clay surface from ferrous chloride solution. Comprehensive studies of the iron mineralogy in these "Mars-soil analogs" were conducted using chemical extractions, solubility analyses, pH and redox, x ray and electron diffractometry, electron microscopic imaging, specific surface area and particle size determinations, differential thermal analyses, magnetic properties characterization, spectral reflectance, and Viking biology simulation experiments. The clay matrix and the procedure used for synthesis produced nanophase iron oxides containing a certain proportion of divalent iron, which slowly converts to more stable, fully oxidized iron minerals. The clay acted as an effective matrix, both chemically and sterically, preventing the major part of the synthesized iron oxides from ripening, i.e., growing and developing larger crystals. The precipitated iron oxides appear as isodiametric or slightly elongated particles in the size range 1-10 nm, having large specific surface area. The noncrystalline nature of the iron compounds precipitated on the surface of the clay was verified by their complete extractability in oxalate. Lepidocrocite (gamma-FeOOH) was detected by selected area electron diffraction. It is formed from a double iron Fe(II)/Fe(III) hydroxy mineral such as "green rust," or ferrosic hydroxide. Magnetic measurements suggested that lepidocrocite converted to the more stable maghemite (gamma-Fe2O3) by mild heat treatment and then to nanophase hematite (alpha-Fe2O3) by extensive heat treatment. After mild heating, the iron-enriched clay became slightly magnetic, to the extent that it adheres to a hand-held magnet, as was observed with Mars soil. The chemical reactivity of the iron-enriched clays strongly resembles, and offers a plausible mechanism

  16. Minerals yearbook, 1982. volume 1. metals and minerals

    SciTech Connect

    Not Available

    1984-01-01

    This volume of the Minerals Yearbook, covering metals and minerals, contains 73 commodity or commodity group chapters with data on approximately 90 minerals that were obtained as a result of the mineral information gathering activities of the Bureau of Mines. In addition, the volume contains a chapter on mining and quarrying trends and a statistical summary.

  17. Minerals yearbook, 1983. Volume 1. Metals and minerals

    SciTech Connect

    Not Available

    1984-01-01

    This volume of the Minerals Yearbook, covering metals and minerals, contains 73 commodity or commodity group chapters with data on approximately 90 minerals that were obtained as a result of the mineral information gathering activities of the Bureau of Mines. In addition, the volume contains a chapter on mining and quarrying trends and a statistical summary.

  18. Hunting for eruption ages in accessory minerals

    NASA Astrophysics Data System (ADS)

    Vazquez, J. A.

    2012-12-01

    A primary goal in geochronology is to provide precise and accurate ages for tephras that serve as chronostratigraphic markers for constraining the timing and rates of volcanism, sedimentation, climate change, and catastrophic events in Earth history. Zircon remains the most versatile accessory mineral for dating silicic tephras due to its common preservation in distal pyroclastic deposits, as well as the robustness of its U-Pb and U-series systems even after host materials have been hydrothermally altered or weathered. Countless studies document that zircon may be complexly zoned in age due to inheritance, contamination, recycling of antecrysts, protracted crystallization in long-lived magma reservoirs, or any combination of these. Other accessory minerals such as allanite or chevkinite can retain similar records of protracted crystallization. If the goal is to date the durations of magmatic crystallization, differentiation, and/or magma residence, then these protracted chronologies within and between accessory minerals are a blessing. However, if the goal is to date the timing of eruption with high precision, i.e., absolute ages with millennial-scale uncertainties, then this age zoning is a curse. Observations from ion microprobe 238U-230Th dating of Pleistocene zircon and allanite provide insight into the record of near-eruption crystallization in accessory minerals and serve as a guide for high-precision whole-crystal dating. Although imprecise relative to conventional techniques, ion probe analysis allows high-spatial resolution 238U-230Th dating that can document multi-millennial age distributions at the crystal scale. Analysis of unpolished rims and continuous depth profiling of zircon from small and large volume eruptions (e.g., Coso, Mono Craters, Yellowstone) reveals that the final several micrometers of crystallization often yield ages that are indistinguishable from associated eruption ages from the 40Ar/39Ar or (U-Th)/He methods. Using this approach, we

  19. Hydrothermal crystal growth of the potassium niobate and potassium tantalate family of crystals

    SciTech Connect

    Mann, Matthew; Jackson, Summer; Kolis, Joseph

    2010-11-15

    Single crystals of KNbO{sub 3} (KN), KTaO{sub 3} (KT), and KTa{sub 1-x}Nb{sub x}O{sub 3} (x=0.44, KTN) have been prepared by hydrothermal synthesis in highly concentrated KOH mineralizer solutions. The traditional problems of inhomogeneity, non-stoichiometry, crystal striations and crystal cracking resulting from phase transitions associated with this family compounds are minimized by the hydrothermal crystal growth technique. Crystals of good optical quality with only minor amounts of metal ion reduction can be grown this way. Reactions were also designed to provide homogeneous distribution of tantalum and niobium metal centers throughout the KTN crystal lattice to maximize its electro-optic properties. Synthesis was performed at relatively low (500-660 {sup o}C) temperatures in comparison to the flux and Czochralski techniques. This work represents the largest crystals of this family of compounds grown by hydrothermal methods to date. -- Graphical Abstract:

  20. SYNCHROTRON X - RAY OBSERVATIONS OF A MONOLAYER TEMPLATE FOR MINERALIZATION.

    SciTech Connect

    DIMASI,E.; GOWER,L.B.

    2000-11-27

    Mineral nucleation at a Langmuir film interface has been studied by synchrotron x-ray scattering. Diluted calcium bicarbonate solutions were used as subphases for arachidic and stearic acid monolayers, compressed in a Langmuir trough. Self-assembly of the monolayer template is observed directly, and subsequent crystal growth monitored in-situ.

  1. Lactic acid bacterial extract as a biogenic mineral growth modifier

    NASA Astrophysics Data System (ADS)

    Borah, Ballav M.; Singh, Atul K.; Ramesh, Aiyagari; Das, Gopal

    2009-04-01

    The formation of minerals and mechanisms by which bacteria could control their formation in natural habitats is now of current interest for material scientists to have an insight of the mechanism of in vivo mineralization, as well as to seek industrial and technological applications. Crystalline uniform structures of calcium and barium minerals formed micron-sized building blocks when synthesized in the presence of an organic matrix consisting of secreted protein extracts from three different lactic acid bacteria (LAB) viz.: Lactobacillus plantarum MTCC 1325, Lactobacillus acidophilus NRRL B4495 and Pediococcus acidilactici CFR K7. LABs are not known to form organic matrix in biological materialization processes. The influence of these bacterial extracts on the crystallization behavior was investigated in details to test the basic coordination behavior of the acidic protein. In this report, varied architecture of the mineral crystals obtained in presence of high molecular weight protein extracts of three different LAB strains has been discussed. The role of native form of high molecular weight bacterial protein extracts in the generation of nucleation centers for crystal growth was clearly established. A model for the formation of organic matrix-cation complex and the subsequent events leading to crystal growth is proposed.

  2. Minerals Yearbook, 1989. Volume i. Metals and Minerals

    SciTech Connect

    Not Available

    1989-01-01

    The edition of the Minerals Yearbook discusses the performance of the worldwide mineral industry during 1989 and provides background information to assist in interpreting that performance. Volume I, Metals and Minerals, contains chapters on virtually all metallic and industrial mineral commodities important to the U.S. economy. A chapter on advanced materials also has been added to the Minerals Yearbook series beginning with the 1989 volume. In addition, a chapter on survey methods used in data collection with a statistical summary of nonfuel minerals and a chapter on trends in mining and quarrying in the metals and industrial mineral industries are included.

  3. Minerals yearbook, 1993. Volume 1. Metals and minerals. Annual report

    SciTech Connect

    1993-12-31

    This edition of the Minerals Yearbook discusses the performance of the worldwide minerals and materials industry during 1993 and provides background information to assist in interpreting that performance. It contains chapters on virtually all metallic and industrial mineral commodities important to the U.S. economy. A chapter on survey methods with a statistical summary of nonfuel minerals, and a chapter on trends in mining and quarrying in the metals and industrial mineral industries are also included.

  4. Minerals yearbook, 1994. Volume 1. Metals and minerals. Annual report

    SciTech Connect

    1994-12-31

    The edition of the Minerals Yearbook discusses the performance of the worldwide minerals and materials industry during 1994 and provides background information to assist in interpreting that performance. The volume I, Metals and Minerals, contains chapters on virtually all metallic and industrial mineral commodities important to the U.S. economy. The volume also contains chapters on Survey Methods, a Statistical Summary of Nonfuel Minerals, and Trends in Mining and Quarrying.

  5. The mineral economy of Brazil--Economia mineral do Brasil

    USGS Publications Warehouse

    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.

  6. Color of Minerals. Earth Science Curriculum Project Pamphlet Series PS-6.

    ERIC Educational Resources Information Center

    Rapp, George, Jr.

    The causes for many of the colors exhibited by minerals are presented to students. Several theories of modern physics are introduced. The nature of light, the manner in which light interacts with matter, atomic theory, and crystal structure are all discussed in relation to the origin of color in minerals. Included are color pictures of many…

  7. Molecular packing in bone collagen fibrils prior to mineralization

    NASA Astrophysics Data System (ADS)

    Hsiao, Benjamin; Zhou, Hong-Wen; Burger, Christian; Chu, Benjamin; Glimcher, Melvin J.

    2012-02-01

    The three-dimensional packing of collagen molecules in bone collagen fibrils has been largely unknown because even in moderately mineralized bone tissues, the organic matrix structure is severely perturbed by the deposition of mineral crystals. During the past decades, the structure of tendon collagen (e.g. rat tail) --- a tissue that cannot mineralize in vivo, has been assumed to be representative for bone collagen fibrils. Small-angle X-ray diffraction analysis of the native, uncalcified intramuscular fish bone has revealed a new molecular packing scheme, significantly different from the quasi-hexagonal arrangement often found in tendons. The deduced structure in bone collagen fibrils indicates the presence of spatially discrete microfibrils, and an arrangement of intrafibrillar space to form ``channels'', which could accommodate crystals with dimensions typically found in bone apatite.

  8. Measuring the Hardness of Minerals

    ERIC Educational Resources Information Center

    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…

  9. Animal...Vegetable...or Mineral?

    ERIC Educational Resources Information Center

    Cameron, Eugene

    1973-01-01

    Outlines the problems facing the United States with mineral reserves being depleted, and the consumption of minerals outstripping production. Expresses concern about the deteriorating mineral position, and the ignorance and confusion of the public with respect to mineral production and supply, energy requirements, and environmental consequences.…

  10. Abdominal cocoon accompanied by multiple peritoneal loose body

    PubMed Central

    Cheng, Yongyuan; Qu, Lintao; Li, Jun; Wang, Bin; Geng, Junzu; Xing, Dong

    2017-01-01

    Abstract Rationale: Abdominal cocoon and peritoneal loose body are both rare abdominal diseases. Patient concerns: The patient reported in this case was a 47-year-old man who suffered from abdominal pain and distension for 3 days. Diagnosis: X-ray, computed tomography, and magnetic resonance imaging revealed multiple peritoneal loose body and small bowel obstruction, characterized by a total encapsulation of the small bowel with a fibrous membrane. Interventions: The patient underwent surgical treatment and exploratory laparotomy confirmed the diagnosis of abdominal cocoon. Outcomes: Histopathological examination of pelvic nodules confirmed peritoneal loose body. Lessons: To our knowledge, the herein reported case is the first abdominal cocoon that was accompanied by multiple peritoneal loose body. PMID:28248873

  11. Quasiclassical description of bremsstrahlung accompanying {alpha} decay including quadrupole radiation

    SciTech Connect

    Jentschura, U. D.; Milstein, A. I.; Terekhov, I. S.; Boie, H.; Scheit, H.; Schwalm, D.

    2008-01-15

    We present a quasiclassical theory of {alpha} decay accompanied by bremsstrahlung with a special emphasis on the case of {sup 210}Po, with the aim of finding a unified description that incorporates both the radiation during the tunneling through the Coulomb wall and the finite energy E{sub {gamma}} of the radiated photon up to E{sub {gamma}}{approx}Q{sub {alpha}}/{radical}({eta}), where Q{sub {alpha}} is the {alpha}-decay Q-value and {eta} is the Sommerfeld parameter. The corrections with respect to previous quasiclassical investigations are found to be substantial, and excellent agreement with a full quantum mechanical treatment is achieved. Furthermore, we find that a dipole-quadrupole interference significantly changes the {alpha}-{gamma} angular correlation. We obtain good agreement between our theoretical predictions and experimental results.

  12. Traumatic Optic Neuropathy Accompanying Orbital Grease Gun Injury

    PubMed Central

    Park, Ji Hyun; Jang, Jae Woo; Kim, Sung Joo

    2010-01-01

    We report a case of traumatic optic neuropathy accompanying a grease gun injury to the orbit. A 48-year-old man with a grease gun injury visited our clinic with decreased visual acuity, proptosis and limited extraocular movement (EOM). Orbital CT revealed a crescent mass of fat in the medial intraconal space. The grease was exuded from a lacerated conjunctival wound. The visual evoked potential (VEP) test demonstrated a decreased response in the left eye. Proptosis and EOM were improved after surgical removal of the grease. Systemic high-dose corticosteroid therapy was administered for suspected traumatic optic neuropathy, after which VEP nearly recovered, while visual acuity was slightly improved. A second surgery for traumatic cataract did not further improve visual acuity. PMID:20379466

  13. Decomposition of solids accompanied by melting--Bawn kinetics.

    PubMed

    Brown, Michael E; Glass, Beverley D

    2003-03-26

    The book "Chemistry of the Solid State", edited by W.E. Garner more than 50 years ago, contained a chapter (Chapter 10) by C.E.H. Bawn which dealt with the kinetics of the thermal decompositions of solids that are accompanied by some melting. Rate equations were derived and this model has become known as the Bawn model or as "Bawn kinetics". This kinetic model has proved particularly useful in pharmaceutical stability studies. The isothermal curves of extent of decomposition, alpha, against time for this model are sigmoidal and the problems of distinguishing this model from other sigmoidal models (Prout-Tompkins, Avrami-Erofeev) have been examined. Under programmed temperature conditions, distinguishability becomes even more difficult.

  14. Communicating hydrocephalus accompanied by arachnoid cyst in aneurismal subarachnoid hemorrhage.

    PubMed

    Choi, Jae Young; Cha, Seung Heon; Cho, Won Ho; Ko, Jun Kyeung

    2013-12-01

    The authors describe a case of communicating hydrocephalus accompanied by an arachnoid cyst in an aneurismal subarachnoid hemorrhage. A 69-year-old female was referred to our clinic due to the sudden onset of a headache. A head computed tomography scan demonstrated an arachnoid cyst in the right middle fossa with a mass effect and diffuse subarachnoid hemorrhage. Digital subtraction angiography then revealed a left internal carotid-posterior communicating artery aneurysm. The neck of the aneurysm was clipped successfully and the post-operative period was uneventful. However, two months after discharge, the patient reported that her mental status had declined over previous weeks. A cranial computed tomography scan revealed an interval increase in the size of the ventricle and arachnoid cyst causing a midline shift. Simultaneous navigation guided ventriculoperitoneal shunt and cystoperitoneal shunt placement resulted in remarkable radiological and clinical improvements.

  15. Catamenial hemoptysis accompanied by subcutaneous endometriosis treated with combination therapy

    PubMed Central

    Jang, Hye-In; Kim, Sung-Eun; Lee, Yoo-Young; Choi, Chel-Hun; Lee, Jeong-Won; Kim, Byoung-Gie; Bae, Duk-Soo

    2017-01-01

    Extra pelvic endometriosis is considered to be rare. This paper reports a case of catamenial hemoptysis accompanied by subcutaneous endometriosis in 26-year-old woman. A computed tomography scan of the chest revealed a focal ground-glass opacity lesion in the posterior segment of the right upper lobe. Histopathology confirmed the diagnosis of endometriosis of right lung and concurrent subcutaneous endometriosis. She was treated with surgical resection of the endometriosis lesions on two different sites and perioperative gonadotropin-releasing hormone agonist therapy. The 6-month follow-up after combination treatment showed no recurrence. Though long-term follow-up result is needed, aggressive treatment using combination treatment (surgery and perioperative medication) should be considered for symptomatic extra pelvic endometriosis. PMID:28344969

  16. Sudden synchrony leaps accompanied by frequency multiplications in neuronal activity

    PubMed Central

    Vardi, Roni; Goldental, Amir; Guberman, Shoshana; Kalmanovich, Alexander; Marmari, Hagar; Kanter, Ido

    2013-01-01

    A classical view of neural coding relies on temporal firing synchrony among functional groups of neurons, however, the underlying mechanism remains an enigma. Here we experimentally demonstrate a mechanism where time-lags among neuronal spiking leap from several tens of milliseconds to nearly zero-lag synchrony. It also allows sudden leaps out of synchrony, hence forming short epochs of synchrony. Our results are based on an experimental procedure where conditioned stimulations were enforced on circuits of neurons embedded within a large-scale network of cortical cells in vitro and are corroborated by simulations of neuronal populations. The underlying biological mechanisms are the unavoidable increase of the neuronal response latency to ongoing stimulations and temporal or spatial summation required to generate evoked spikes. These sudden leaps in and out of synchrony may be accompanied by multiplications of the neuronal firing frequency, hence offering reliable information-bearing indicators which may bridge between the two principal neuronal coding paradigms. PMID:24198764

  17. Transient positive and negative experiences accompanying stage hypnosis.

    PubMed

    Crawford, H J; Kitner-Triolo, M; Clarke, S W; Olesko, B

    1992-11-01

    Frequency of positive and negative experiences accompanying stage hypnosis was assessed in follow-up interviews with 22 participants of university-sponsored performances. Most subjects described their experience positively (relaxing, interesting, exciting, satisfying, illuminating, and pleasurable), but some described it negatively (confusing, silly, annoying, and frightening). Five subjects (22.7%) reported partial or complete amnesia; all were highly responsive to the stage hypnosis suggestions. One subject was completely unable to breach amnesia and felt annoyed and frightened. Five subjects (22.7%) believed the hypnotist had control over their behavior. Participants (n = 15) tested subsequently on the Stanford Hypnotic Susceptibility Scale, Form C (Weitzenhoffer & Hilgard, 1962) were mostly moderately to highly hypnotizable (M = 7.07), and the scores correlated significantly (r = .68) with the percentage of passed stage hypnosis suggestions.

  18. Structural rearrangement accompanying ligand binding in the GAF domain of CodY from Bacillus subtilis

    PubMed Central

    Levdikov, Vladimir M.; Blagova, Elena; Colledge, Vicki L.; Lebedev, Andrey A.; Williamson, David C.; Sonenshein, Abraham L.; Wilkinson, Anthony J

    2011-01-01

    The GAF domain is a simple module widespread in proteins of diverse function including cell signalling proteins and transcription factors. Its structure, typically spanning 150 residues, has three tiers; a basal layer of two or more α-helices, a middle layer of β-pleated sheet and a top layer formed by segments of the polypeptide that connect strands of the β-sheet. In structures of GAF domains in complex with their effectors, these polypeptide segments envelop the ligand enclosing it in a cavity whose base is formed by the β-sheet, so that ligand binding and release must be accompanied by conformational rearrangements of the distal portion of the structure. Descriptions of binding are presently limited by the absence of a GAF domain for which both liganded and unliganded structures are known. Earlier, we solved the crystal structure of the GAF domain of CodY, a branched chain amino acid and GTP responsive regulator of the transcription of stationary phase and virulence genes in Bacillus, in complexes with isoleucine and valine. Here, we report the structure of this domain in its unliganded form, allowing definition of the structural changes accompanying ligand binding. The core of the protein and its dimerisation interface are essentially unchanged in agreement with circular dichroism spectroscopy experiments that show that the secondary structure composition is unperturbed by ligand binding. There is however, extensive refolding of the binding site loops, with up to 15 Å movements of the coiled segment linking β3 and β4, such that in the absence of the ligand, the binding pocket is not formed. The implications of these structural rearrangements for ligand affinity and specificity are discussed. Finally, saturation transfer difference NMR spectroscopy showed binding of isoleucine, but not GTP, to the GAF domain suggesting that the two cofactors do not have a common binding site. PMID:19500589

  19. Middleware Design for Swarm-Driving Robots Accompanying Humans

    PubMed Central

    Kim, Min Su; Kim, Sang Hyuck; Kang, Soon Ju

    2017-01-01

    Research on robots that accompany humans is being continuously studied. The Pet-Bot provides walking-assistance and object-carrying services without any specific controls through interaction between the robot and the human in real time. However, with Pet-Bot, there is a limit to the number of robots a user can use. If this limit is overcome, the Pet-Bot can provide services in more areas. Therefore, in this study, we propose a swarm-driving middleware design adopting the concept of a swarm, which provides effective parallel movement to allow multiple human-accompanying robots to accomplish a common purpose. The functions of middleware divide into three parts: a sequence manager for swarm process, a messaging manager, and a relative-location identification manager. This middleware processes the sequence of swarm-process of robots in the swarm through message exchanging using radio frequency (RF) communication of an IEEE 802.15.4 MAC protocol and manages an infrared (IR) communication module identifying relative location with IR signal strength. The swarm in this study is composed of the master interacting with the user and the slaves having no interaction with the user. This composition is intended to control the overall swarm in synchronization with the user activity, which is difficult to predict. We evaluate the accuracy of the relative-location estimation using IR communication, the response time of the slaves to a change in user activity, and the time to organize a network according to the number of slaves. PMID:28218650

  20. Brain–Immune Interaction Accompanying Odor-Evoked Autobiographic Memory

    PubMed Central

    Matsunaga, Masahiro; Bai, Yu; Yamakawa, Kaori; Toyama, Asako; Kashiwagi, Mitsuyoshi; Fukuda, Kazuyuki; Oshida, Akiko; Sanada, Kazue; Fukuyama, Seisuke; Shinoda, Jun; Yamada, Jitsuhiro; Sadato, Norihiro; Ohira, Hideki

    2013-01-01

    The phenomenon in which a certain smell evokes a specific memory is known as the Proust phenomenon. Odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli. The results of our previous study indicated that odor-evoked autobiographic memory accompanied by positive emotions has remarkable effects on various psychological and physiological activities, including the secretion of cytokines, which are immune-signaling molecules that modulate systemic inflammation. In this study, we aimed to clarify the neural substrates associated with the interaction between odor-evoked autobiographic memory and peripheral circulating cytokines. We recruited healthy male and female volunteers and investigated the association between brain responses and the concentration of several cytokines in the plasma by using positron emission tomography (PET) recordings when an autographic memory was evoked in participants by asking them to smell an odor that was nostalgic to them. Participants experienced positive emotions and autobiographic memories when nostalgic odors were presented to them. The levels of peripheral proinflammatory cytokines, such as the tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), were significantly reduced after experiencing odor-evoked autobiographic memory. Subtraction analysis of PET images indicated that the medial orbitofrontal cortex (mOFC) and precuneus/posterior cingulate cortex (PCC) were significantly activated during experiences of odor-evoked autobiographic memory. Furthermore, a correlation analysis indicated that activities of the mOFC and precuneus/PCC were negatively correlated with IFN-γ concentration. These results indicate that the neural networks including the precuneus/PCC and mOFC might regulate the secretion of peripheral proinflammatory cytokines during the experience of odor-evoked autobiographic memories accompanied with positive emotions. PMID:23977312

  1. American Strategic Minerals

    NASA Astrophysics Data System (ADS)

    DeYoung, John H., Jr.; Chidester, Alfred H.

    American Strategic Minerals is a collection of six papers that were presented in December 1982 at a conference organized by the Center for the Study of Marine Policy at the University of Delaware. According to editor Gerard J. Mangone, director of the center, the papers were commissioned “to investigate not only the objective resource situation, but also past United States policy on strategic minerals and future options open to Washington.” The authors and their chapter titles are John C. Kraft, University of Delaware: “Strategic minerals and world stability” V. Anthony Cammarota, Jr., U.S. Bureau of Mines: “America's dependence on strategic minerals” John D. Morgan, U.S. Bureau of Mines: “Future demands of the United States for strategic minerals” J. Robert Moore, University of Texas: “Alternative sources of strategic minerals from the seabed” Allan I. Mendelowitz and John E. Watson, U.S. General Accounting Office: “U.S. mining investments in developing countries” and James W. Curlin, Nautilus Press: “The political dimensions of strategic minerals.”

  2. Crystal clear

    NASA Astrophysics Data System (ADS)

    2012-02-01

    A semiconductor is usually opaque to any light whose photon energy is larger than the semiconductor bandgap. Nature Photonics spoke to Stephen Durbin about how to render GaAs semiconductor crystals transparent using intense X-ray pulses.

  3. Computer simulation studies of minerals

    NASA Astrophysics Data System (ADS)

    Oganov, Artem Romaevich

    Applications of state-of-the-art computer simulations to important Earth- and rock-forming minerals (Al2SiO5 polymorphs, albite (NaAlSi3O8), and MgSiO3 perovskite) are described. Detailed introductions to equations of state and elasticity, phase transitions, computer simulations, and geophysical background are given. A new general classification of phase transitions is proposed, providing a natural framework for discussion of structural, thermodynamic, and kinetic aspects of phase transitions. The concept of critical bond distances is introduced. For Si-O bonds this critical distance is 2.25 A. Using atomistic simulations, anomalous Al-Si antiordering in albite is explained. A first-order isosymmetric transition associated with a change in the ordering scheme is predicted at high pressures. A quantum-mechanical study is presented for the Al2SiO5 polymorphs: kyanite, andalusite, sillimanite, and hypothetical pseudobrookite-like and V3O5-like phases (the latter phase was believed to be the main Al mineral of the lower mantle). It is shown that above 11 GPa all the Al2SiO5 phases break down into the mixture of oxides: corundum (Al2O3) and stishovite (SiO2). Atomisation energies, crystal structures and equations of state of all the Al2SiO5 polymorphs, corundum, stishovite, quartz (SiO2) have been determined. Metastable pressure-induced transitions in sillimanite and andalusite are predicted at ~30-50 GPa and analysed in terms of structural changes and lattice dynamics. Sillimanite (Pbnm) transforms into incommensurate and isosymmetric (Pbnm) phases; andalusite undergoes pressure-induced amorphisation. Accurate quantum-mechanical thermal equation of state is obtained for MgSiO3 perovskite, the main Earth-forming mineral. Results imply that a pure-perovskite mantle is unlikely. I show that MgSiO3 perovskite is not a Debye-like solid, contrary to a common assumption. First ever ab initio molecular dynamics calculations of elastic constants at finite temperatures are

  4. Multiple Fractures in Patient with Graves' Disease Accompanied by Isolated Hypogonadotropic Hypogonadism

    PubMed Central

    Yi, Hyon-Seung; Kim, Ji Min; Ju, Sang Hyeon; Lee, Younghak; Kim, Hyun Jin

    2016-01-01

    Isolated hypogonadotropic hypogonadism (IHH) is known to decrease bone mineral density due to deficiency of sex steroid hormone. Graves' disease is also an important cause of secondary osteoporosis. However, IHH does not preclude the development of primary hyperthyroidism caused by Graves' disease, leading to more severe osteoporosis rapidly. Here, we describe the first case of 35-year-old Asian female patient with IHH accompanied by Graves' disease and osteoporosis-induced multiple fractures. Endocrine laboratory findings revealed preserved anterior pituitary functions except for secretion of gonadotropins and showed primary hyperthyroidism with positive autoantibodies. Sella magnetic resonance imaging showed slightly small sized pituitary gland without mass lesion. Dual energy X-ray absorptiometry revealed severe osteoporosis in lumbar spine and femur neck of the patient. Plain film radiography of the pelvis and shoulder revealed a displaced and nondisplaced fracture, respectively. After surgical fixation with screws for the femoral fracture, the patient was treated with antithyroid medication, calcium, and vitamin D until now and has been recovering fairly well. We report a patient of IHH with Graves' disease and multiple fractures that is a first case in Korea. PMID:26981520

  5. Thorium in mineral products.

    PubMed

    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.

  6. Mineral mining installations

    SciTech Connect

    Werner, G.; Wisniewski, P.

    1983-12-15

    A mineral mining installation serves to win mineral by explosive blasting. The installation employs a shuttle conveyor arranged alongside a mineral face. Roof supports stand side-by-side at the side of the conveyor remote from the conveyor. The roof supports are connected to the conveyor through shifting rams and have roof-engageable caps or the like supported on hydraulic props. The pans of the conveyor have upstanding walls at the rear side nearest the roof supports which carry rails at their upper ends. The roof caps have wall components pivoted thereto and hydraulic piston and cylinder units serve to swing the wall components up and down. When explosive blasting takes place the wall components are swung down to engage on the walls of the conveyor pans to form a screen between the winning region and the access region of the working.

  7. Mineral find highlights cruise

    NASA Astrophysics Data System (ADS)

    Katzoff, Judith A.

    Heavy minerals with potential commercial value were discovered last month by the U.S. Geological Survey (USGS) in seafloor deposits off the coasts of Virginia and Georgia. The USGS sent the research vessel J. W. Powell on a 25-day cruise along the East Coast to assess the concentrations of commercially important minerals in that segment of the U.S. Exclusive Economic Zone (EEZ).Assistant Secretary of the Interior Robert Broadbent called the findings of the Powell “promising” and said they served as a “reminder of just how little we do know about the seafloor resources just a few miles offshore.”

  8. Microbially mediated mineral carbonation

    NASA Astrophysics Data System (ADS)

    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

  9. Minerals Yearbook 1989: Boron

    SciTech Connect

    Lyday, P.A.

    1990-08-01

    U.S. production and sales of boron minerals and chemicals decreased during the year. Domestically, glass fiber insulation was the largest use for borates, followed by sales to distributors, textile-grade glass fibers, and borosilicate glasses. California was the only domestic source of boron minerals. The United States continued to provide essentially all of its own supply while maintaining a strong position as a source of sodium borate products and boric acid exported to foreign markets. Supplementary U.S. imports of Turkish calcium borate and calcium-sodium borate ores, borax, and boric acid, primarily for various glass uses, continued.

  10. Mineral chemistry of tourmaline from Mashak Pahar, South Purulia Shear Zone (SPSZ), eastern Indian Shield

    NASA Astrophysics Data System (ADS)

    Acharjee, Santanu; Ray, Jyotisankar; Dey, Payel; Bhattacharyya, Debapriya; Banerjee, Mousumi; Chattopadhyay, Basab; Sengupta, Shyamal; Bhatt, A. K.; Chowdhury, D.; Dwivedi, A. K.; Mahato, Sanjoy; Jana, Arka Ranjan; Maithani, P. B.; Ramesh Babu, P. V.

    2016-12-01

    The area of investigation at and around Mashak Pahar, Bankura district, West Bengal, India comprises a number of rock types namely: granite gneiss, migmatized quartz tourmaline gneiss, quartz pebble conglomerate, ferruginous quartzite, quartz tourmaline veins (as veins) and graphite schists. Interestingly, the study area lies in the region extending South Purulia Shear Zone (˜Tamar-Porapahar Shear Zone) which marks the boundary between two contrasting tectonic blocks of eastern India, namely, the Chhotanagpur Gneissic Terrane (CGC) to the north and Singhbhum Group of rocks to the south. The rocks of the study area are poly-phasedly deformed by three phases of folding, namely, F1, F2 and F3. All the tourmalines are classified to be of `Alkali Group'. Chemistry of tourmalines from migmatized quartz tourmaline gneiss and those from quartz tourmaline veins are in conformity with their relation to (earthquake induced) shear system evolution in this terrain. In general, the compositional evolution of tourmaline during prograde metamorphism (˜400°-730°C) has been supported by both petrographic and chemical evidences. Assessment of mineral-chemical data of constituent tourmaline grains clearly suggests compositional variations across zonal boundaries within tourmaline that was controlled by changing metamorphic milieu in this terrane. Field and petrographic evidences clearly indicate activation of earlier and later shears in this region accompanied by infiltration of boron and formation of zoned tourmaline crystals.

  11. Mercuric iodide single crystals for nuclear radiation detectors

    SciTech Connect

    Li, W.; Li, Z.; Zhu, S.; Yin, S.; Zhao, B.; Chen, G.; Yin, S.; Yuan, H.; Xu, H.

    1996-06-01

    Large size HgI{sub 2} single crystals were grown using the Modified Temperature Oscillation Method (MTOM) with low dislocation densities in a relatively stable temperature environment. Radiation detectors were fabricated from the single crystals which showed good energy resolution with small polarization. Applications have been found in geological explorations, marine mineral analysis, environment pollution monitoring, industrial material quality assurance, and space explorations.

  12. Mineral Collections and Modern Technology: Roles in Geosciences Education and Research

    NASA Astrophysics Data System (ADS)

    Holl, C. M.; Chadwick, J.; Duffy, T. S.

    2011-12-01

    The role of geologic collections has diminished over the years as new technology has lead to emphasis on computer based modeling and theoretical work in the geosciences. Mineralogy and petrology tend to be thought of as mature sciences, and many departments are cutting back or eliminating courses in these subjects. Collections that accompany instruction and provide material for research projects are likewise becoming unappreciated. What is overlooked is that the same progress in technology has also created new opportunities for utilization of collections, through greater accessibility to the scientific community and the application of new analytical techniques to older materials. We are reviving a dormant mineral collection in the Department of Geosciences at Princeton University with the intent of reaffirming the role of geologic collections in mineralogy and petrology educational curricula and research. The collection had been undermanaged and underutilized for decades until the recent renovation, which will include organization and preservation of the specimens, plus digitization of the catalog. Though in the mid-stages, the renovation has already led to several educational and research projects for undergraduates in the department. For example, one undergraduate student is using Raman spectroscopy, a technique that did not yet exist when the collection was assembled, to various gem and mineral specimens in the collection, including some unique materials that have not yet been studied in this way. Another undergraduate student is assisting with organization of the collection, and in the process discovering rare and unique specimens that had been overlooked for decades, as well as using the opportunity to learn hands-on systematic mineralogy. Yet another restored a collection of antique wooden crystal models while learning crystallographic point groups. Thanks to technology, these opportunities will not be limited to students in a geology department fortunate

  13. The crystal cavities of the New Jersey zeolite region

    USGS Publications Warehouse

    Schaller, Waldemar Theodore

    1932-01-01

    The crystal cavities present in the mineral complex of the New Jersey traprock region have long excited the interest of mineralogists. In 1914 Fenner made the first detailed and comprehensive study of these cavities and suggested that babingtonite was the original mineral. Soon after this anhydrite was found occupying parts of some of the cavities at one of the quarries. At this time, too, Wherry concluded that glauberite was the original mineral of some of the cavities because of his studies of similar crystal cavities in Triassic shale at different places.

  14. Alginate hydrogel-mediated crystallization of calcium carbonate

    SciTech Connect

    Ma, Yufei; Feng, Qingling

    2011-05-15

    We documented a specific method for combining calcium ions and alginate molecules slowly and continuously in the mineralization system for the purpose of understanding the mediating function of alginate on the crystallization of calcium carbonate. The alginate was involved in the nucleation and the growth process of CaCO{sub 3}. The crystal size, morphology and roughness of crystal surface were significantly influenced by the type of the alginate, which could be accounted for by the length of the G blocks in alginate. A combination of Fourier transform infrared spectroscopy and thermogravimetric analysis showed that there were the chemical interactions between the alginate and the mineral phase. This strategic approach revealed the biologically controlled CaCO{sub 3} mineralization within calcium alginate hydrogels via the selective nucleation and the confined crystallization of CaCO{sub 3}. The results presented here could contribute to the understanding of the mineralization process in hydrogel systems. -- Graphical abstract: Schematic illustration of the growth of calcite aggregates with different morphologies obtained from (a) Low G alginate gels and (b) High G alginate gels. Display Omitted highlights: > We use a specific method for combining calcium ions and alginate molecules slowly and continuously in the mineralization system to understand the mediating function of alginate on the crystallization of CaCO{sub 3} crystals. > The crystal size, morphology and crystal surface roughness are influenced by the length of G blocks in alginate. There are chemical interactions between the alginate and the mineral phase. > We propose a potential mechanism of CaCO{sub 3} crystallization within High G and Low G calcium alginate hydrogel.

  15. Nacre biomineralisation: A review on the mechanisms of crystal nucleation.

    PubMed

    Nudelman, Fabio

    2015-10-01

    The wide diversity of biogenic minerals that is found in nature, each with its own morphology, mechanical properties and composition, is remarkable. In order to produce minerals that are optimally adapted for their function, biomineralisation usually occurs under strict cellular control. This control is exerted by specialised proteins and polysaccharides that assemble into a 3-dimensional organic matrix framework, forming a microenvironment where mineral deposition takes place. Molluscs are unique in that they use a striking variety of structural motifs to build their shells, each made of crystals with different morphologies and different calcium carbonate polymorphs. Much of want is known about mollusc shell formation comes from studies on the nacreous layer, or mother-of-pearl. In this review, we discuss two existing models on the nucleation of aragonite crystals during nacre formation: heteroepitaxial nucleation and mineral bridges. The heteroepitaxial nucleation model is based on the identification of chemical functional groups and aragonite-nucleating proteins at the centre of crystal imprints. It proposes that during nacre formation, each aragonite tablet nucleates independently on a nucleation site that is formed by acidic proteins and/or glycoproteins adsorbed on the chitin scaffold. The mineral bridges model is based on the identification of physical connections between the crystals in a stack, which results in a large number of crystals across several layers sharing the same crystallographic orientation. These observations suggest that there is one nucleation event per stack of tablets. Once the first crystal nucleates and reaches the top interlamellar matrix, it continues growing through pores, giving rise to the next layer of nacre, subsequently propagating into a stack. We compare both models and propose that they work in concert to control crystal nucleation in nacre. De novo crystal nucleation has to occur at least once per stack of aligned crystals

  16. Rock and Mineral Bingo: Applying and Assessing Student Rock and Mineral Knowledge and Identification Skills

    NASA Astrophysics Data System (ADS)

    Pound, K. S.

    2005-12-01

    A rock and mineral "Bingo" that is based on knowledge and identification skills (not luck) was developed to help teachers and introductory as well as more advanced-level students develop and improve rock and mineral identification skills. The game was initially designed to use a rock and mineral kit provided to all students in Lab Classes, but could be adapted for any suite of samples. The rock and mineral kits include 13 mineral samples (olivine, pyroxene, amphibole, biotite, muscovite, potassium feldspar, plagioclase, quartz, galena, gypsum, hematite, pyrite, calcite), 7 igneous rock samples (rhyolite, granite, andesite, diorite, basalt, gabbro, peridotite), 3 sedimentary rock samples (sandstone, shale, limestone), and 5 metamorphic rock samples (slate, mica schist, gneiss, marble, quartzite). The kit also includes a small magnifying glass, a streak plate and a tempered steel nail. The Bingo cards are composed of 9 squares ("questions") each. A total of 8 groups of questions have been developed to encompass introductory through more advanced levels. The question sets developed so far are: (a) General distinction between rocks and minerals; (b) Igneous, sedimentary and metamorphic rocks; (c) Mineral luster; (d) Mineral fracture and cleavage; (e) Mineral crystal form; (f) Mineral chemistry; (g) General mineralogy; (h) Geologic Context. Each square on the card is numbered (1-9). The same card is used for each group of questions. The questions are written on a separate set of small question cards that are color-coded (according to question set) and numbered. These cards are pulled out of the `bag' by the caller, and a copy of the question is posted for all to see. The players need to choose the sample from their collection that best fits the question or description given by the caller. The questions are set up so that some samples fit more than one answer, which requires the students to review their choices. The first person or group to win presents their board and

  17. Identification of Minerals

    ERIC Educational Resources Information Center

    Allison, Diane

    2005-01-01

    The lab described in this article was developed to satisfy two major goals. First, the activity is designed to show students the proper techniques used to identify the seven characteristics of all minerals. Second, the lab gives students a glimpse into the life of a professional field geologist. The author has students complete this lab at the end…

  18. New mineral physics panels

    NASA Astrophysics Data System (ADS)

    The AGU Committee on Mineral Physics has formed itself into six panels. The committee chairman is Orson L. Anderson of the Department of Earth and Space Sciences, University of California, Los Angeles; foreign secretary is Robert Liebermann, Department of Earth and Space Sciences, State University of New York, Stony Brook. The six panels are as follows.

  19. Liquid Crystals

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Thermochromic liquid crystals, or TLCs, are a type of liquid crystals that react to changes in temperature by changing color. The Hallcrest/NASA collaboration involved development of a new way to visualize boundary layer transition in flight and in wind tunnel testing of aircraft wing and body surfaces. TLCs offered a new and potentially better method of visualizing the boundary layer transition in flight. Hallcrest provided a liquid crystal formulation technique that afforded great control over the sensitivity of the liquid crystals to varying conditions. Method is of great use to industry, government and universities for aerodynamic and hydrodynamic testing. Company's principal line is temperature indicating devices for industrial use, such as non-destructive testing and flaw detection in electric/electronic systems, medical application, such as diagnostic systems, for retail sale, such as room, refrigerator, baby bath and aquarium thermometers, and for advertising and promotion specials. Additionally, Hallcrest manufactures TLC mixtures for cosmetic applications, and liquid crystal battery tester for Duracell batteries.

  20. Melatonin production accompanies arousal from daily torpor in Siberian hamsters.

    PubMed

    Larkin, Jennie E; Yellon, Steven M; Zucker, Irving

    2003-01-01

    Arousal from deep hibernation is accompanied by a transient rise of melatonin (Mel) in circulation; there are no comparable analyses of Mel concentrations in species that undergo much shallower, shorter duration episodes of daily torpor. Serum Mel concentrations were determined during arousal from both natural daily torpor and torpor induced by 2-deoxy-D-glucose (2-DG) treatment (2,500 mg/kg, intraperitoneal [IP]); blood samples were drawn from the retro-orbital sinus of anesthetized Siberian hamsters. For animals kept in darkness during torpor, Mel concentrations were highest during early arousal when thermogenesis is maximal, and they decreased as body temperature increased during arousal and returned to baseline once euthermia was reestablished. In hamsters kept in the light during the torpor bout, Mel concentrations were elevated above basal values during arousal, but the response was significantly blunted in comparison with values recorded in darkness. Increased Mel concentrations were detected in hamsters only during arousal from torpor (either natural or 2-DG induced) and were not simply a result of the drug treatment; hamsters that remained euthermic or manifested mild hypothermia after drug treatment maintained basal Mel concentrations. We propose that increased Mel production may reflect enhanced sympathetic activation associated with intense thermogenesis during arousal from torpor rather than an adjustment of the circadian rhythm of Mel secretion.

  1. Osmotic stress is accompanied by protein glycation in Arabidopsis thaliana

    PubMed Central

    Paudel, Gagan; Bilova, Tatiana; Schmidt, Rico; Greifenhagen, Uta; Berger, Robert; Tarakhovskaya, Elena; Stöckhardt, Stefanie; Balcke, Gerd Ulrich; Humbeck, Klaus; Brandt, Wolfgang; Sinz, Andrea; Vogt, Thomas; Birkemeyer, Claudia; Wessjohann, Ludger; Frolov, Andrej

    2016-01-01

    Among the environmental alterations accompanying oncoming climate changes, drought is the most important factor influencing crop plant productivity. In plants, water deficit ultimately results in the development of oxidative stress and accumulation of osmolytes (e.g. amino acids and carbohydrates) in all tissues. Up-regulation of sugar biosynthesis in parallel to the increasing overproduction of reactive oxygen species (ROS) might enhance protein glycation, i.e. interaction of carbonyl compounds, reducing sugars and α-dicarbonyls with lysyl and arginyl side-chains yielding early (Amadori and Heyns compounds) and advanced glycation end-products (AGEs). Although the constitutive plant protein glycation patterns were characterized recently, the effects of environmental stress on AGE formation are unknown so far. To fill this gap, we present here a comprehensive in-depth study of the changes in Arabidopsis thaliana advanced glycated proteome related to osmotic stress. A 3 d application of osmotic stress revealed 31 stress-specifically and 12 differentially AGE-modified proteins, representing altogether 56 advanced glycation sites. Based on proteomic and metabolomic results, in combination with biochemical, enzymatic and gene expression analysis, we propose monosaccharide autoxidation as the main stress-related glycation mechanism, and glyoxal as the major glycation agent in plants subjected to drought. PMID:27856706

  2. Mitochondrial Bioenergetics in the Metabolic Myopathy Accompanying Peripheral Artery Disease

    PubMed Central

    Rontoyanni, Victoria G.; Nunez Lopez, Omar; Fankhauser, Grant T.; Cheema, Zulfiqar F.; Rasmussen, Blake B.; Porter, Craig

    2017-01-01

    Peripheral artery disease (PAD) is a serious but relatively underdiagnosed and undertreated clinical condition associated with a marked reduction in functional capacity and a heightened risk of morbidity and mortality. The pathophysiology of lower extremity PAD is complex, and extends beyond the atherosclerotic arterial occlusion and subsequent mismatch between oxygen demand and delivery to skeletal muscle mitochondria. In this review, we evaluate and summarize the available evidence implicating mitochondria in the metabolic myopathy that accompanies PAD. Following a short discussion of the available in vivo and in vitro methodologies to quantitate indices of muscle mitochondrial function, we review the current evidence implicating skeletal muscle mitochondrial dysfunction in the pathophysiology of PAD myopathy, while attempting to highlight questions that remain unanswered. Given the rising prevalence of PAD, the detriment in quality of life for patients, and the associated significant healthcare resource utilization, new alternate therapies that ameliorate lower limb symptoms and the functional impairment associated with PAD are needed. A clear understanding of the role of mitochondria in the pathophysiology of PAD may contribute to the development of novel therapeutic interventions. PMID:28348531

  3. Structural changes accompanying phosphorylation of tarantula muscle myosin filaments

    PubMed Central

    1987-01-01

    Electron microscopy has been used to study the structural changes that occur in the myosin filaments of tarantula striated muscle when they are phosphorylated. Myosin filaments in muscle homogenates maintained in relaxing conditions (ATP, EGTA) are found to have nonphosphorylated regulatory light chains as shown by urea/glycerol gel electrophoresis and [32P]phosphate autoradiography. Negative staining reveals an ordered, helical arrangement of crossbridges in these filaments, in which the heads from axially neighboring myosin molecules appear to interact with each other. When the free Ca2+ concentration in a homogenate is raised to 10(-4) M, or when a Ca2+-insensitive myosin light chain kinase is added at low Ca2+ (10(-8) M), the regulatory light chains of myosin become rapidly phosphorylated. Phosphorylation is accompanied by potentiation of the actin activation of the myosin Mg- ATPase activity and by loss of order of the helical crossbridge arrangement characteristic of the relaxed filament. We suggest that in the relaxed state, when the regulatory light chains are not phosphorylated, the myosin heads are held down on the filament backbone by head-head interactions or by interactions of the heads with the filament backbone. Phosphorylation of the light chains may alter these interactions so that the crossbridges become more loosely associated with the filament backbone giving rise to the observed changes and facilitating crossbridge interaction with actin. PMID:2958483

  4. Splanchnectopia Accompanied With Atrial Septal Defect: A Case Report

    PubMed Central

    Bao, Ning; Zhang, Yu

    2011-01-01

    Splanchnetopia accompanied with atrial septal defect is a rare congenital malformation clinically. Recent studies show that the patients are susceptible to lung disease. We present a case of a 62-year-old man who presented to our hospital with cough, palpitation and short of breath after activity. On physical examination, we found cyanosis of lips and face, swollen jugular vein, bubble sounds at the lung bottom, irregular heart rhythm, the large liver under the left rib and the lower limbs edema. Laboratory studies revealed white blood cell 18.6 × 109/L and neutrophils 73.9%. Electrocardiogram showed disappearance of P wave and substituted F wave with irregular R-R interval. Ultrasound cardiogram indicated that there was a 24 mm-long gap in the middle of the atrial septal. Dextrocardia, pulmonary artery extrudes and infection of lung were found by chest x-ray. The abdomen ultrasound indicated organ flip. Clinical diagnosis was congenital heart disease, splanchnectopia, atrial septal defect, Eisenmenger’s syndrome, atrial flutter, cardiac function class III and pneumonia. The patient left hospital after 2-week treatment. Its clinical significance is when the thoracic and celiac organs are ill, the position of the symptoms and physical signs are contrary to the normal place. Therefore, we should make a careful and systematic examination of the patients in order to avoid misdiagnosis and delay in treatment.

  5. [Iliopsoas abscess accompanied by epidural abscess--a case report].

    PubMed

    Fukushige, Tetsushi; Sano, Tomomi; Yamada, Sinichi; Ueda, Sawako; Kano, Tatsuhiko

    2003-09-01

    A 55-year-old man was admitted to a hospital with pain of the low back as well as the left leg, and fever. He was suspected of suffering from the lumbar disc herniation because of the presence of Lasegue's sign on the first physical examination. Abdominal computed tomography, however, revealed the swelling of the left iliopsoas muscle. Iliopsoas abscess accompanied epidural abscess was confirmed by subsequent magnetic resonance imaging (MRI). Antibiotic therapy was started for the successive 8 days. The fever resolved, but the pain persisted. The abscess extending from the iliopsoas muscle to the epidural space was still seen on the MRI 20 days after the completion of the antibiotic therapy, and he still complained of the pain of his low back and left leg. Therefore, we conducted epidural puncture under fluoroscopic guidance. Approximately 3 ml of pus was aspirated from the epidural space. Then, his complains decreased remarkably. Iliopsoas abscess should be taken into account in case of a patient with pain on the low back and leg and also inflammatory signs such as fever and leucocytosis.

  6. Increased spatial variance accompanies reorganization of two continental shelf ecosystems.

    PubMed

    Litzow, Michael A; Urban, J Daniel; Laurel, Benjamin J

    2008-09-01

    Phase transitions between alternate stable states in marine ecosystems lead to disruptive changes in ecosystem services, especially fisheries productivity. We used trawl survey data spanning phase transitions in the North Pacific (Gulf of Alaska) and the North Atlantic (Scotian Shelf) to test for increases in ecosystem variability that might provide early warning of such transitions. In both time series, elevated spatial variability in a measure of community composition (ratio of cod [Gadus sp.] abundance to prey abundance) accompanied transitions between ecosystem states, and variability was negatively correlated with distance from the ecosystem transition point. In the Gulf of Alaska, where the phase transition was apparently the result of a sudden perturbation (climate regime shift), variance increased one year before the transition in mean state occurred. On the Scotian Shelf, where ecosystem reorganization was the result of persistent overfishing, a significant increase in variance occurred three years before the transition in mean state was detected. However, we could not reject the alternate explanation that increased variance may also have simply been inherent to the final stable state in that ecosystem. Increased variance has been previously observed around transition points in models, but rarely in real ecosystems, and our results demonstrate the possible management value in tracking the variance of key parameters in exploited ecosystems.

  7. Massively augmented hippocampal dentate granule cell activation accompanies epilepsy development.

    PubMed

    Dengler, Christopher G; Yue, Cuiyong; Takano, Hajime; Coulter, Douglas A

    2017-02-20

    In a mouse model of temporal lobe epilepsy, multicellular calcium imaging revealed that disease emergence was accompanied by massive amplification in the normally sparse, afferent stimulation-induced activation of hippocampal dentate granule cells. Patch recordings demonstrated reductions in local inhibitory function within the dentate gyrus at time points where sparse activation was compromised. Mimicking changes in inhibitory synaptic function and transmembrane chloride regulation was sufficient to elicit the dentate gyrus circuit collapse evident during epilepsy development. Pharmacological blockade of outward chloride transport had no effect during epilepsy development, and significantly increased granule cell activation in both control and chronically epileptic animals. This apparent occlusion effect implicates reduction in chloride extrusion as a mechanism contributing to granule cell hyperactivation specifically during early epilepsy development. Glutamine plays a significant role in local synthesis of GABA in synapses. In epileptic mice, sparse granule cell activation could be restored by glutamine application, implicating compromised GABA synthesis. Glutamine had no effect on granule cell activation earlier, during epilepsy development. We conclude that compromised feedforward inhibition within the local circuit generates the massive dentate gyrus circuit hyperactivation evident in animals during and following epilepsy development. However, the mechanisms underlying this disinhibition diverge significantly as epilepsy progresses.

  8. [A case of infected subdural hematoma accompanied by cerebral infarction].

    PubMed

    Fujii, Norio; Naito, Yuichiro; Takanashi, Shigehiko; Ueno, Toshiaki; Nakagomi, Tadayoshi

    2013-05-01

    Infected subdural hematoma(ISH)is a rare disease caused by hematogenous infection of a preexisting subdural hematoma. We report a rare case of ISH accompanied by cerebral infarction. A 76-year-old man who had suffered a closed head injury 3 months before presented fever, headache and left hemiparesis during the medical treatment of acute cholangitis and obstructive jaundice with pancreatic cancer at the department of surgical gastroenterology. At the consultation, computed tomography(CT)scan indicated right chronic subdural hematoma. We performed a burr hole opening surgery on the same day. Abscess and hematoma was aspirated from the subdural space, and methicillin-resistant Staphylococcus aureus(MRSA)was detected in this specimen. Thus the diagnosis of the infected subdural hematoma was confirmed. However, despite the antibiotics therapy, follow-up CT showed a low-density area close to the residual abscess, which suggested cerebral infarction. Cerebral angiography showed a vasospasm at the cortical segment of the right middle cerebral artery near the residual abscess. Eventually we carried out a small craniotomy to evacuate the abscess. Our case showed that prompt surgical treatment is required in case of ISH and the whole hematoma and abscess should be removed as soon as possible with an image diagnosis and an additional surgical operation.

  9. Massively augmented hippocampal dentate granule cell activation accompanies epilepsy development

    PubMed Central

    Dengler, Christopher G.; Yue, Cuiyong; Takano, Hajime; Coulter, Douglas A.

    2017-01-01

    In a mouse model of temporal lobe epilepsy, multicellular calcium imaging revealed that disease emergence was accompanied by massive amplification in the normally sparse, afferent stimulation-induced activation of hippocampal dentate granule cells. Patch recordings demonstrated reductions in local inhibitory function within the dentate gyrus at time points where sparse activation was compromised. Mimicking changes in inhibitory synaptic function and transmembrane chloride regulation was sufficient to elicit the dentate gyrus circuit collapse evident during epilepsy development. Pharmacological blockade of outward chloride transport had no effect during epilepsy development, and significantly increased granule cell activation in both control and chronically epileptic animals. This apparent occlusion effect implicates reduction in chloride extrusion as a mechanism contributing to granule cell hyperactivation specifically during early epilepsy development. Glutamine plays a significant role in local synthesis of GABA in synapses. In epileptic mice, sparse granule cell activation could be restored by glutamine application, implicating compromised GABA synthesis. Glutamine had no effect on granule cell activation earlier, during epilepsy development. We conclude that compromised feedforward inhibition within the local circuit generates the massive dentate gyrus circuit hyperactivation evident in animals during and following epilepsy development. However, the mechanisms underlying this disinhibition diverge significantly as epilepsy progresses. PMID:28218241

  10. [Metabolic status and bone mineral density in patients with pseudarthrosis of long bones in hyperhomocysteinemia].

    PubMed

    Bezsmertnyĭ, Iu O

    2013-06-01

    In article described research of the metabolic status and bone mineral density in 153 patients with with pseudarthrosis of long bones, in individuals with consolidated fractures and healthy people. The violations of reparative osteogenesis at hyperhomocysteinemia are accompanied by disturbances of the functional state of bone tissue, inhibition of biosynthetic and increased destruction processes, reduced bone mineral density in the formation of osteopenia and osteoporosis. The degree and direction of change of bone depends on the type of violation of reparative osteogenesis.

  11. Active site remodelling accompanies thioester bond formation in the SUMO E1

    SciTech Connect

    Olsen, Shaun K.; Capili, Allan D.; Lu, Xuequan; Tan, Derek S.; Lima, Christopher D.

    2010-03-30

    E1 enzymes activate ubiquitin (Ub) and ubiquitin-like (Ubl) proteins in two steps by carboxy-terminal adenylation and thioester bond formation to a conserved catalytic cysteine in the E1 Cys domain. The structural basis for these intermediates remains unknown. Here we report crystal structures for human SUMO E1 in complex with SUMO adenylate and tetrahedral intermediate analogues at 2.45 and 2.6 {angstrom}, respectively. These structures show that side chain contacts to ATP-Mg are released after adenylation to facilitate a 130 degree rotation of the Cys domain during thioester bond formation that is accompanied by remodelling of key structural elements including the helix that contains the E1 catalytic cysteine, the crossover and re-entry loops, and refolding of two helices that are required for adenylation. These changes displace side chains required for adenylation with side chains required for thioester bond formation. Mutational and biochemical analyses indicate these mechanisms are conserved in other E1s.

  12. Active site remodelling accompanies thioester bond formation in the SUMO E1.

    PubMed

    Olsen, Shaun K; Capili, Allan D; Lu, Xuequan; Tan, Derek S; Lima, Christopher D

    2010-02-18

    E1 enzymes activate ubiquitin (Ub) and ubiquitin-like (Ubl) proteins in two steps by carboxy-terminal adenylation and thioester bond formation to a conserved catalytic cysteine in the E1 Cys domain. The structural basis for these intermediates remains unknown. Here we report crystal structures for human SUMO E1 in complex with SUMO adenylate and tetrahedral intermediate analogues at 2.45 and 2.6 A, respectively. These structures show that side chain contacts to ATP.Mg are released after adenylation to facilitate a 130 degree rotation of the Cys domain during thioester bond formation that is accompanied by remodelling of key structural elements including the helix that contains the E1 catalytic cysteine, the crossover and re-entry loops, and refolding of two helices that are required for adenylation. These changes displace side chains required for adenylation with side chains required for thioester bond formation. Mutational and biochemical analyses indicate these mechanisms are conserved in other E1s.

  13. Macrophage-Mediated Clofazimine Sequestration Is Accompanied by a Shift in Host Energy Metabolism.

    PubMed

    Trexel, Julie; Yoon, Gi S; Keswani, Rahul K; McHugh, Cora; Yeomans, Larisa; Vitvitsky, Victor; Banerjee, Ruma; Sud, Sudha; Sun, Yihan; Rosania, Gus R; Stringer, Kathleen A

    2017-04-01

    Prolonged (8 weeks) oral administration of clofazimine results in a profound pharmacodynamic response-bioaccumulation in macrophages (including Kupffer cells) as intracellular crystal-like drug inclusions (CLDIs) with an associated increase in interleukin-1 receptor antagonist production. Notably, CLDI formation in Kupffer cells concomitantly occurs with the formation of macrophage-centric granulomas. Accordingly, we sought to understand the impact of these events on host metabolism using (1)H-nuclear magnetic resonance metabolomics. Mice received a clofazimine or vehicle-enriched (sham) diet for at least 8 weeks. At 2 weeks, the antimicrobial activity of clofazimine was evident by changes in urine metabolites. From 2 to 8 weeks, there was a striking change in metabolite levels indicative of a reorientation of host energy metabolism paralleling the onset of CLDI and granuloma formation. This was evidenced by a progressive reduction in urine levels of metabolites involved in one-carbon metabolism with corresponding increases in whole blood, and changes in metabolites associated with lipid, nucleotide and amino acid metabolism, and glycolysis. Although clofazimine-fed mice ate more, they gained less weight than control mice. Together, these results indicate that macrophage sequestration of clofazimine as CLDIs and granuloma formation is accompanied by a profound metabolic disruption in energy homeostasis and one-carbon metabolism.

  14. Single Crystals Grown Under Unconstrained Conditions

    NASA Astrophysics Data System (ADS)

    Sunagawa, Ichiro

    Based on detailed investigations on morphology (evolution and variation in external forms), surface microtopography of crystal faces (spirals and etch figures), internal morphology (growth sectors, growth banding and associated impurity partitioning) and perfection (dislocations and other lattice defects) in single crystals, we can deduce how and by what mechanism the crystal grew and experienced fluctuation in growth parameters through its growth and post-growth history under unconstrained condition. The information is useful not only in finding appropriate way to growing highly perfect and homogeneous single crystals, but also in deciphering letters sent from the depth of the Earth and the Space. It is also useful in discriminating synthetic from natural gemstones. In this chapter, available methods to obtain molecular information are briefly summarized, and actual examples to demonstrate the importance of this type of investigations are selected from both natural minerals (diamond, quartz, hematite, corundum, beryl, phlogopite) and synthetic crystals (SiC, diamond, corundum, beryl).

  15. Minerals yearbook 1977. Volume I. Metals and minerals

    SciTech Connect

    Not Available

    1980-01-01

    This report contains chapters on virtually all metallic and nonmetallic mineral commodities important to the domestic economy. In addition, it includes a general review chapter on the mineral industries, a chapter on mining and quarrying trends, and a statistical summary.

  16. An overview of vertebrate mineralization with emphasis on collagen-mineral interaction

    NASA Technical Reports Server (NTRS)

    Landis, W. J.

    1999-01-01

    The nucleation, growth, and development of mineral crystals through their interaction principally with collagen in normal bone and calcifying tendon have been elaborated by applying a number of different techniques for analysis of the inorganic and organic constituents of these tissues. The methods have included conventional and high voltage electron microscopy, electron diffraction, microscopic tomography and 3D image reconstruction, and atomic force microscopy. This summary presents results of these studies that have now characterized the size, shape, and aspects of the chemical nature of the crystals as well as their orientation, alignment, location, and distribution with respect to collagen. These data have provided the means for understanding more completely the formation and strength of the collagen-mineral composite present in most vertebrate calcifying tissues and, from that information, a basis for the adaptation of such tissues under mechanical constraints. In the context of the latter point, other data are given showing effects on collagen in bone cell cultures subjected to the unloading parameters of spaceflight. Implications of these results may be particularly relevant to explaining loss of bone by humans and other vertebrate animals during missions in space, during situations of extended fracture healing, long-term bedrest, physical immobilization, and related conditions. In a broader sense, the data speak to the response of bone and mineralized vertebrate tissues to changes in gravitational loading and applied mechanical forces in general.

  17. Large Deformation Mechanisms, Plasticity, and Failure of an Individual Collagen Fibril With Different Mineral Content.

    PubMed

    Depalle, Baptiste; Qin, Zhao; Shefelbine, Sandra J; Buehler, Markus J

    2016-02-01

    Mineralized collagen fibrils are composed of tropocollagen molecules and mineral crystals derived from hydroxyapatite to form a composite material that combines optimal properties of both constituents and exhibits incredible strength and toughness. Their complex hierarchical structure allows collagen fibrils to sustain large deformation without breaking. In this study, we report a mesoscale model of a single mineralized collagen fibril using a bottom-up approach. By conserving the three-dimensional structure and the entanglement of the molecules, we were able to construct finite-size fibril models that allowed us to explore the deformation mechanisms which govern their mechanical behavior under large deformation. We investigated the tensile behavior of a single collagen fibril with various intrafibrillar mineral content and found that a mineralized collagen fibril can present up to five different deformation mechanisms to dissipate energy. These mechanisms include molecular uncoiling, molecular stretching, mineral/collagen sliding, molecular slippage, and crystal dissociation. By multiplying its sources of energy dissipation and deformation mechanisms, a collagen fibril can reach impressive strength and toughness. Adding mineral into the collagen fibril can increase its strength up to 10 times and its toughness up to 35 times. Combining crosslinks with mineral makes the fibril stiffer but more brittle. We also found that a mineralized fibril reaches its maximum toughness to density and strength to density ratios for a mineral density of around 30%. This result, in good agreement with experimental observations, attests that bone tissue is optimized mechanically to remain lightweight but maintain strength and toughness.

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

    PubMed

    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.

  19. Sea urchin tooth mineralization: Calcite present early in the aboral plumula

    PubMed Central

    Stock, Stuart R.; Veis, Arthur; Xiao, Xianghui; Almer, Jonathan D.; Dorvee, Jason R.

    2012-01-01

    In both vertebrate bone, containing carbonated hydroxyapatite as the mineral phase, and in invertebrate hard tissue comprised of calcium carbonate, a popular view is that the mineral phase develops from a long-lived amorphous precursor which later transforms into crystal form. Important questions linked to this popular view are: When and where is the crystallized material formed, and is amorphous solid added subsequently to the crystalline substrate? Sea urchin teeth, in which the earliest mineral forms within isolated compartments, in a time and position dependent manner, allow direct investigation of the timing of crystallization of the calcite primary plates. Living teeth of the sea urchin Lytechinus variegatus, in their native coelomic fluid, were examined by high-energy synchrotron x-ray diffraction. The diffraction data show that calcite is present in the most aboral portions of the plumula, representing the very earliest stages of mineralization, and that this calcite has the same crystal orientation as in the more mature adoral portions of the same tooth. Raman spectroscopy of the aboral plumula confirms the initial primary plate mineral material is calcite and does not detect amorphous calcium carbonate; in the more mature adoral incisal flange, it does detect a broader calcite peak, consistent with two or more magnesium compositions. We hypothesize that some portion of each syncytial membrane in the plumula provides the information for nucleation of identically oriented calcite crystals that subsequently develop to form the complex geometry of the single crystal sea urchin tooth. PMID:22940703

  20. Minerals yearbook, 1985. Volume 1. Metals and minerals

    SciTech Connect

    Not Available

    1987-01-01

    This volume of the 1985 Minerals Yearbook, covering metals and minerals, contains 72 commodity or commodity group chapters with data on approximately 90 minerals that were obtained as a result of the mineral information gathering activities of the Bureau of Mines. In addition, the volume contains a chapter on mining and quarrying trends, a chapter discussing the statistical surveying methods used by the Bureau of Mines, and a statistical summary.

  1. Minerals yearbook, 1984. Volume 1. Metals and minerals

    SciTech Connect

    Not Available

    1985-01-01

    The volume of the Minerals Yearbook, covering metals and minerals, contains 72 commodity or commodity group chapters with data on approximately 90 minerals that were obtained as a result of the mineral information gathering activities of the Bureau of Mines. In addition, the volume contains a chapter on mining and quarrying trends, a chapter discussing the statistical surveying methods used by the Bureau of Mines, and a statistical summary.

  2. Minerals Yearbook, 1988. Volume 1. Metals and minerals

    SciTech Connect

    Not Available

    1990-01-01

    Volume I of the 1988 Minerals Yearbook, covering metals and minerals, contains 79 commodity or commodity group chapters with data on approximately 90 minerals that were obtained as a result of the mineral information gathering activities of the U.S. Bureau of Mines. In addition, the volume contains chapters on mining and quarrying trends and on the statistical surveying methods used by the Bureau of Mines and a statistical summary.

  3. Ice nucleation properties of the most abundant mineral dust phases

    NASA Astrophysics Data System (ADS)

    Zimmermann, Frank; Weinbruch, Stephan; Schütz, Lothar; Hofmann, Heiko; Ebert, Martin; Kandler, Konrad; Worringen, Annette

    2008-12-01

    The ice nucleation properties of the nine most abundant minerals occurring in desert aerosols (quartz, albite, microcline, kaolinite, montmorillonite, illite, calcite, gypsum, and hematite) were investigated by environmental scanning electron microscopy (ESEM). In this instrument, the pure minerals are exposed to water vapor at variable pressures and temperatures. The crystallization of ice on the mineral particles is observed by secondary electron imaging, and the supersaturation for an activated particle fraction of 1-3% is determined as function of temperature. In all experiments, condensation of water prior to ice formation was not observed within detectable limits, even at water supersaturation. The highest temperatures for 1-3% activation vary between -10°C and -16°C for the nine minerals investigated, and the corresponding onset relative humidities relative to ice RHi between 107 and 117%. Supersaturation temperature curves for initial ice formation (1-3% activation) in the temperature range typical for mixed-phase clouds were measured for all nine minerals. The temperature dependence of the onset relative humidity is strongly dependent on mineralogy. Kaolinite, montmorillonite, and hematite show a strong increase in RHi with decreasing temperature, whereas RHi is almost constant for illite, albite, quartz, and calcite. The highly variable ice nucleation properties of the various mineral dust components should be considered for parameterization schemes. Illite and kaolinite are the most important minerals to consider, as they have high ice nucleation efficiency and are common components of desert aerosols.

  4. Exploring Solid-State Structure and Physical Properties: A Molecular and Crystal Model Exercise

    ERIC Educational Resources Information Center

    Bindel, Thomas H.

    2008-01-01

    A crystal model laboratory exercise is presented that allows students to examine relations among the microscopic-macroscopic-symbolic levels, using crystalline mineral samples and corresponding crystal models. Students explore the relationship between solid-state structure and crystal form. Other structure-property relationships are explored. The…

  5. Adsorption of RNA on mineral surfaces and mineral precipitates

    PubMed Central

    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. PMID:28382177

  6. SYMMETRICAL LASER CRYSTALS.

    DTIC Science & Technology

    CRYSTAL GROWTH , SYMMETRY(CRYSTALLOGRAPHY), LASERS, SYNTHESIS, FERROELECTRIC CRYSTALS , FLUORESCENCE, IMPURITIES, BARIUM COMPOUNDS, ZIRCONATES...STRONTIUM COMPOUNDS, TITANATES, STANNATES, SAMARIUM, MANGANESE, REFRACTORY MATERIALS, OXIDES, SINGLE CRYSTALS .

  7. EEG signatures accompanying auditory figure-ground segregation.

    PubMed

    Tóth, Brigitta; Kocsis, Zsuzsanna; Háden, Gábor P; Szerafin, Ágnes; Shinn-Cunningham, Barbara G; Winkler, István

    2016-11-01

    In everyday acoustic scenes, figure-ground segregation typically requires one to group together sound elements over both time and frequency. Electroencephalogram was recorded while listeners detected repeating tonal complexes composed of a random set of pure tones within stimuli consisting of randomly varying tonal elements. The repeating pattern was perceived as a figure over the randomly changing background. It was found that detection performance improved both as the number of pure tones making up each repeated complex (figure coherence) increased, and as the number of repeated complexes (duration) increased - i.e., detection was easier when either the spectral or temporal structure of the figure was enhanced. Figure detection was accompanied by the elicitation of the object related negativity (ORN) and the P400 event-related potentials (ERPs), which have been previously shown to be evoked by the presence of two concurrent sounds. Both ERP components had generators within and outside of auditory cortex. The amplitudes of the ORN and the P400 increased with both figure coherence and figure duration. However, only the P400 amplitude correlated with detection performance. These results suggest that 1) the ORN and P400 reflect processes involved in detecting the emergence of a new auditory object in the presence of other concurrent auditory objects; 2) the ORN corresponds to the likelihood of the presence of two or more concurrent sound objects, whereas the P400 reflects the perceptual recognition of the presence of multiple auditory objects and/or preparation for reporting the detection of a target object.

  8. Entropic phase transitions and accompanying anomalous thermodynamics of matter

    NASA Astrophysics Data System (ADS)

    Iosilevskiy, I. L.

    2015-11-01

    Thermodynamic consequences of subdivision for all first-order phase transitions (PT) into enthalpy- and entropy-driven ones (H-PT and S-PT), proposed previously [arXiv:1403.8053], are under discussions. Key-value for proposed discrimination is main benefit (decreasing) in enthalpy or (nega)entropy in spontaneous phase decomposition, i.e. the sign of latent heat of PT and consequent slope of its P(T)-dependence. The main driving mechanism for many isostructural S-PT is the decay (delocalization) of some kind of bound complexes, e.g. atoms, molecules etc. Thermodynamic features of H-PT and S-PT differ significantly. Entropic PT are always the part of more general thermodynamic anomaly—domain where great number of usually positive second cross derivatives (e.g. Grüneisen parameter, thermal pressure coefficient etc.) became negative simultaneously. This domain is restricted (in the case of isostructural S-PT) by remarkable bound, where all mentioned second derivatives are equal to zero. Isostructural S-PT has more complicated topology of stable, metastable and unstable states and their boundaries—binodals and spinodals in comparison with ordinary enthalpic PTs. Two new thermodynamic objects accompany isostructural S-PT: (i) appearance of third (additional) region of metastable states with positive compressibility, isolated from the regions of stable states; (ii) appearance of new additional spinodal, topped with a new singular point, separating metastable and unstable states. These additional spinodal and singular point obey to relation (∂P/∂V)T = ∞. All thermodynamic anomalies of entropic PTs correspond to conclusive and transparent geometrical feature of such PTs: multilayered structure of thermodynamic surfaces for temperature, entropy and internal energy as pressure- density functions U(P, V), S(P, V) and T(P, V).

  9. Oxygen Extraction from Minerals

    NASA Technical Reports Server (NTRS)

    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

  10. Bio-inspired mineralization of hydroxyapatite in 3D silk fibroin hydrogel for bone tissue engineering.

    PubMed

    Jin, Yashi; Kundu, Banani; Cai, Yurong; Kundu, Subhas C; Yao, Juming

    2015-10-01

    To fabricate hard tissue implants with bone-like structure using a biomimetic mineralization method is drawing much more attentions in bone tissue engineering. The present work focuses in designing 3D silk fibroin hydrogel to modulate the nucleation and growth of hydroxyapatite crystals via a simple ion diffusion method. The study indicates that Ca(2+) incorporation within the hydrogel provides the nucleation sites for hydroxyapatite crystals and subsequently regulates their oriented growth. The mineralization process is regulated in a Ca(2+) concentration- and minerlization time-dependent way. Further, the compressive strength of the mineralized hydrogels is directly proportional with the mineral content in hydrogel. The orchestrated organic/inorganic composite supports well the viability and proliferation of human osteoblast cells; improved cyto-compatibility with increased mineral content. Together, the present investigation reports a simple and biomimetic process to fabricate 3D bone-like biomaterial with desired efficacy to repair bone defects.

  11. Relations of ammonium minerals at several hydrothermal systems in the western U.S.

    NASA Astrophysics Data System (ADS)

    Krohn, M. Dennis; Kendall, Carol; Evans, John R.; Fries, Terry L.

    1993-08-01

    Ammonium bound to silicate and sulfate minerals has recently been located at several major hydrothermal systems in the western U.S. utilizing newly-discovered near-infrared spectral properties. Knowledge of the origin and mineralogic relations of ammonium minerals at known hydrothermal systems is critical for the proper interpretation of remote sensing data and for testing of possible links to mineralization. Submicroscopic analysis of ammonium minerals from two mercury- and gold-bearing hot-springs deposits at Ivanhoe, Nevada and McLaughlin, California shows that the ammonium feldspar, buddingtonite, occurs as fine-grained euhedral crystals coating larger sulfide and quartz crystals. Ammonium feldspar seems to precipitate relatively late in the crystallization sequence and shows evidence for replacement of NH 4 + by K + or other monovalent cations. Some buddingtonite is observed in close association with mercury, but not with gold. Ammonioalunite is found in a variety of isolated crystal forms at both deposits. Nitrogen isotopic values for ammonium-bearing minerals show a 14‰ range in composition, precluding assignment of a specific provenance to the nitrogen. The correlations of nitrogen isotopic values with depth and ammonium content suggest some loss of nitrogen in the oxidizing supergene environment, possibly as a metastable mineral. The high ammonium content in these hydrothermal systems, the close association to mercury, and the small crystal size of the ammonium-bearing minerals all suggest that ammonium may be transported in a late-stage vapor phase or as an organic volatile. Such a process could lead to the formation of a non-carbonaceous organic aureole above a buried geothermal source. The discovery of a 10-km outcrop of ammonium minerals confirms that significant substitution of ammonium in minerals is possible over an extensive area and that remote sensing is a feasible means to detect such aureoles.

  12. Relations of ammonium minerals at several hydrothermal systems in the western U.S.

    USGS Publications Warehouse

    Krohn, M.D.; Kendall, C.; Evans, J.R.; Fries, T.L.

    1993-01-01

    Ammonium bound to silicate and sulfate minerals has recently been located at several major hydrothermal systems in the western U.S. utilizing newly-discovered near-infrared spectral properties. Knowledge of the origin and mineralogic relations of ammonium minerals at known hydrothermal systems is critical for the proper interpretation of remote sensing data and for testing of possible links to mineralization. Submicroscopic analysis of ammonium minerals from two mercury- and gold-bearing hot-springs deposits at Ivanhoe, Nevada and McLaughlin, California shows that the ammonium feldspar, buddingtonite, occurs as fine-grained euhedral crystals coating larger sulfide and quartz crystals. Ammonium feldspar seems to precipitate relatively late in the crystallization sequence and shows evidence for replacement of NH4+ by K+ or other monovalent cations. Some buddingtonite is observed in close association with mercury, but not with gold. Ammonioalunite is found in a variety of isolated crystal forms at both deposits. Nitrogen isotopic values for ammonium-bearing minerals show a 14??? range in composition, precluding assignment of a specific provenance to the nitrogen. The correlations of nitrogen isotopic values with depth and ammonium content suggest some loss of nitrogen in the oxidizing supergene environment, possibly as a metastable mineral. The high ammonium content in these hydrothermal systems, the close association to mercury, and the small crystal size of the ammonium-bearing minerals all suggest that ammonium may be transported in a late-stage vapor phase or as an organic volatile. Such a process could lead to the formation of a non-carbonaceous organic aureole above a buried geothermal source. The discovery of a 10-km outcrop of ammonium minerals confirms that significant substitution of ammonium in minerals is possible over an extensive area and that remote sensing is a feasible means to detect such aureoles. ?? 1993.

  13. Mineral oil soluble borate compositions

    SciTech Connect

    Dulat, J.

    1981-09-15

    Alkali metal borates are reacted with fatty acids or oils in the presence of a low hlb value surfactant to give a stable mineral oil-soluble product. Mineral oil containing the borate can be used as a cutting fluid.

  14. Carbon dioxide sequestration by aqueous mineral carbonation of magnesium silicate minerals

    SciTech Connect

    Gerdemann, Stephen J.; Dahlin, David C.; O'Connor, William K.; Penner, Larry R.

    2003-01-01

    The dramatic increase in atmospheric carbon dioxide since the Industrial Revolution has caused concerns about global warming. Fossil-fuel-fired power plants contribute approximately one third of the total human-caused emissions of carbon dioxide. Increased efficiency of these power plants will have a large impact on carbon dioxide emissions, but additional measures will be needed to slow or stop the projected increase in the concentration of atmospheric carbon dioxide. By accelerating the naturally occurring carbonation of magnesium silicate minerals it is possible to sequester carbon dioxide in the geologically stable mineral magnesite (MgCO3). The carbonation of two classes of magnesium silicate minerals, olivine (Mg2SiO4) and serpentine (Mg3Si2O5(OH)4), was investigated in an aqueous process. The slow natural geologic process that converts both of these minerals to magnesite can be accelerated by increasing the surface area, increasing the activity of carbon dioxide in the solution, introducing imperfections into the crystal lattice by high-energy attrition grinding, and in the case of serpentine, by thermally activating the mineral by removing the chemically bound water. The effect of temperature is complex because it affects both the solubility of carbon dioxide and the rate of mineral dissolution in opposing fashions. Thus an optimum temperature for carbonation of olivine is approximately 185 degrees C and 155 degrees C for serpentine. This paper will elucidate the interaction of these variables and use kinetic studies to propose a process for the sequestration of the carbon dioxide.

  15. Therapeutic Crystals

    ERIC Educational Resources Information Center

    Bond, Charles S.

    2014-01-01

    Some readers might not fully know what the difference is between crystallography, and the "new age" practice of dangling crystals around the body to capitalise on their healing energy. The latter is often considered to be superstition, while ironically, the former has actually resulted in real rationally-based healing of human diseases…

  16. Comparing Crystals

    ERIC Educational Resources Information Center

    Sharp, Janet; Hoiberg, Karen; Chumbley, Scott

    2003-01-01

    This standard lesson on identifying salt and sugar crystals expands into an opportunity for students to develop their observation, questioning, and modeling skills. Although sugar and salt may look similar, students discovered that they looked very different under a magnifying glass and behaved differently when dissolved in water. In addition,…

  17. Optical Crystals

    ERIC Educational Resources Information Center

    Bergsten, Ronald

    1974-01-01

    Discusses the production and structure of a sequence of optical crystals which can serve as one-, two-, and three-dimensional diffraction plates to illustrate diffraction patterns by using light rather than x-rays or particles. Applications to qualitative presentations of Laue theory at the secondary and college levels are recommended. (CC)

  18. Laboratory Spectroscopy of Astrophysically Important Minerals

    NASA Astrophysics Data System (ADS)

    Maukonen, Douglas; Brusentsova, T. N.; Figueiredo, P.; Saxena, H.; Peale, R.; Nissinboim, A.; Boesenberg, J.; Leibold, J.; Sherman, K.; Harlow, G. E.; Ebel, D. S.; Hibbitts, K.; Lisse, C. M.

    2010-10-01

    To aid in interpreting data from Herschel Space Observatory's Photodetector Array Camera and Spectrometer (PACS), we spectrally characterized 146 species of minerals from the American Museum of Natural History's mineral, rock, and meteorite collections in the 15 to 250 micron wavelength range. Chemical and crystallographic identity of all samples were confirmed by means of electron microprobe and x-ray multi-grain micro-diffraction. Species investigated included nesosilicate olivines, silicas, pyroxenes, feldspars, carbonates, phyllosilicates, oxides, and sulfides. Samples were ground to micron dimensions, with micron size distributions ensured by Stokes precipitation and confirmed by scanning electron microscopy. Milligram quantities were then dispersed in polyethylene powder and melted into pellets. Spectra were collected using a Fourier spectrometer with globar source, pellicle beamsplitters, and a 4 K bolometer. Temperature dependence of the spectra down to 15 K revealed sharpening and blue-shifts of the characteristic absorption lines, and in some cases the resolution of additional spectral features occurred at low temperatures. Generally, the spectra are highly characteristic of chemical composition and crystal structure. We suggest the use of these results for mineral identification in the far-infrared emission spectra of interplanetary dust, dust in protoplanetary disks, and comet dust tails. All spectra will be posted in public data bases. Funding was provided by NASA-JPL.

  19. Biomolecular Modification of Inorganic Crystal Growth

    SciTech Connect

    De Yoreo, J J

    2007-04-27

    The fascinating shapes and hierarchical designs of biomineralized structures are an inspiration to materials scientists because of the potential they suggest for biomolecular control over materials synthesis. Conversely, the failure to prevent or limit tissue mineralization in the vascular, skeletal, and urinary systems is a common source of disease. Understanding the mechanisms by which organisms direct or limit crystallization has long been a central challenge to the biomineralization community. One prevailing view is that mineral-associated macromolecules are responsible for either inhibiting crystallization or initiating and stabilizing non-equilibrium crystal polymorphs and morphologies through interactions between anionic moieties and cations in solution or at mineralizing surfaces. In particular, biomolecules that present carboxyl groups to the growing crystal have been implicated as primary modulators of growth. Here we review the results from a combination of in situ atomic force microscopy (AFM) and molecular modeling (MM) studies to investigate the effect of specific interactions between carboxylate-rich biomolecules and atomic steps on crystal surfaces during the growth of carbonates, oxalates and phosphates of calcium. Specifically, we how the growth kinetics and morphology depend on the concentration of additives that include citrate, simple amino acids, synthetic Asp-rich polypeptides, and naturally occurring Asp-rich proteins found in both functional and pathological mineral tissues. The results reveal a consistent picture of shape modification in which stereochemical matching of modifiers to specific atomic steps drives shape modification. Inhibition and other changes in growth kinetics are shown to be due to a range of mechanisms that depend on chemistry and molecular size. Some effects are well described by classic crystal growth theories, but others, such as step acceleration due to peptide charge and hydrophylicity, were previously unrealized

  20. Mineral bridges in nacre.

    PubMed

    Checa, Antonio G; Cartwright, Julyan H E; Willinger, Marc-Georg

    2011-12-01

    We confirm with high-resolution techniques the existence of mineral bridges between superposed nacre tablets. In the towered nacre of both gastropods and the cephalopod Nautilus there are large bridges aligned along the tower axes, corresponding to gaps (150-200nm) in the interlamellar membranes. Gaps are produced by the interaction of the nascent tablets with a surface membrane that covers the nacre compartment. In the terraced nacre of bivalves bridges associated with elongated gaps in the interlamellar membrane (>100nm) have mainly been found at or close to the edges of superposed parental tablets. To explain this placement, we hypothesize that the interlamellar membrane breaks due to differences in osmotic pressure across it when the interlamellar space below becomes reduced at an advanced stage of calcification. In no cases are the minor connections between superimposed tablets (<60nm), earlier reported to be mineral bridges, found to be such.

  1. Mixtures and Mineral Reactions

    NASA Astrophysics Data System (ADS)

    Rumble, D.

    The monograph Mixtures and Mineral Reactions contains a large amount of information of value to mineralogists, petrologists, and geochemists. The first four chapters are a succinct account of the thermodynamic description of crystalline solutions. In these early chapters a comparison is made between different mathematical treatments of activitycomposition models, there is a discussion of the unmixing by exsolution of a single solution into two phases, and methods of computing phase equilibria in assemblages of different minerals are given. If the reader is perplexed by the discussion of standard states (cf. Figure 1.3), not to worry. That is a normal condition for anyone forced to choose between equivalent reference frames yet knowing, somewhere down the line, that the choice will ultimately make one's computational life more or less difficult.

  2. Clay Mineral: Radiological Characterization

    SciTech Connect

    Cotomacio, J. G.; Silva, P. S. C.; Mazzilli, B. P

    2008-08-07

    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 {sup 40}K in these clay minerals.The objective of this work is to determine the concentrations of {sup 238}U, {sup 232}Th, {sup 226}Ra, {sup 228}Ra, {sup 210}Pb and {sup 40}K 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 {sup 238}U and {sup 232}Th activity concentration was made by alpha spectrometry and gamma spectrometry was used for {sup 226}Ra, {sup 228}Ra, {sup 210}Pb and {sup 40}K determination. Some physical-chemical parameters were also determined as organic carbon and pH. The average activity concentration obtained was 906{+-}340 Bq kg{sup -1} for {sup 40}K, 40{+-}9 Bq kg{sup -1} for {sup 226}Ra, 75{+-}9 Bq kg{sup -1} for {sup 228}Ra, 197{+-}38 Bq kg{sup -1} for {sup 210}Pb, 51{+-}26 Bq kg{sup -1} for {sup 238}U and 55{+-}24 Bq kg{sup -1} for {sup 232}Th, considering both kinds of clay.

  3. Structural relations between collagen and mineral in bone as determined by high voltage electron microscopic tomography.

    PubMed

    Landis, W J; Hodgens, K J; Arena, J; Song, M J; McEwen, B F

    1996-02-01

    Aspects of the ultrastructural interaction between collagen and mineral crystals in embryonic chick bone have been examined by the novel technique of high voltage electron microscopic tomography to obtain three-dimensional information concerning extracellular calcification in this tissue. Newly mineralizing osteoid along periosteal surfaces of mid-diaphyseal regions from normal chick tibiae was embedded, cut into 0.25 microns thick sections, and documented at 1.0 MV in the Albany AEI-EM7 high voltage electron microscope. The areas of the tissue studied contained electron dense mineral crystals associated with collagen fibrils, some marked by crystals disposed along their cylindrically shaped lengths. Tomographic reconstructions of one site with two mineralizing fibrils were computed from a 5 degrees tilt series of micrographs over a +/- 60 degrees range. Reconstructions showed that the mineral crystals were platelets of irregular shape. Their sizes were variable, measured here up to 80 x 30 x 8 nm in length, width, and thickness, respectively. The longest crystal dimension, corresponding to the c-axis crystallographically, was generally parallel to the collagen fibril long axis. Individual crystals were oriented parallel to one another in each fibril examined. They were also parallel in the neighboring but apparently spatially separate fibrils. Crystals were periodically (approximately 67 nm repeat distance) arranged along the fibrils and their location appeared to correspond to collagen hole and overlap zones defined by geometrical imaging techniques. The crystals appeared to be continuously distributed along a fibril, their size and number increasing in a tapered fashion from a relatively narrow tip containing smaller and infrequent crystals to wider regions having more densely packed and larger crystals. Defined for the first time by direct visual 3D imaging, these data describe the size, shape, location, orientation, and development of early crystals in normal

  4. Structural relations between collagen and mineral in bone as determined by high voltage electron microscopic tomography

    NASA Technical Reports Server (NTRS)

    Landis, W. J.; Hodgens, K. J.; Arena, J.; Song, M. J.; McEwen, B. F.

    1996-01-01

    Aspects of the ultrastructural interaction between collagen and mineral crystals in embryonic chick bone have been examined by the novel technique of high voltage electron microscopic tomography to obtain three-dimensional information concerning extracellular calcification in this tissue. Newly mineralizing osteoid along periosteal surfaces of mid-diaphyseal regions from normal chick tibiae was embedded, cut into 0.25 microns thick sections, and documented at 1.0 MV in the Albany AEI-EM7 high voltage electron microscope. The areas of the tissue studied contained electron dense mineral crystals associated with collagen fibrils, some marked by crystals disposed along their cylindrically shaped lengths. Tomographic reconstructions of one site with two mineralizing fibrils were computed from a 5 degrees tilt series of micrographs over a +/- 60 degrees range. Reconstructions showed that the mineral crystals were platelets of irregular shape. Their sizes were variable, measured here up to 80 x 30 x 8 nm in length, width, and thickness, respectively. The longest crystal dimension, corresponding to the c-axis crystallographically, was generally parallel to the collagen fibril long axis. Individual crystals were oriented parallel to one another in each fibril examined. They were also parallel in the neighboring but apparently spatially separate fibrils. Crystals were periodically (approximately 67 nm repeat distance) arranged along the fibrils and their location appeared to correspond to collagen hole and overlap zones defined by geometrical imaging techniques. The crystals appeared to be continuously distributed along a fibril, their size and number increasing in a tapered fashion from a relatively narrow tip containing smaller and infrequent crystals to wider regions having more densely packed and larger crystals. Defined for the first time by direct visual 3D imaging, these data describe the size, shape, location, orientation, and development of early crystals in normal

  5. Down syndrome--genetic and nutritional aspects of accompanying disorders.

    PubMed

    Mazurek, Dominika; Wyka, Joanna

    2015-01-01

    Down syndrome (DS) is one of the more commonly occurring genetic disorders, where mental retardation is combined with nutritional diseases. It is caused by having a third copy of chromosome 21, and there exist 3 forms; Simple Trisomy 21, Translocation Trisomy and Mosaic Trisomy. Symptoms include intellectual disability/mental retardation, early onset of Alzheimer's disease and the appearance of various phenotypic features such as narrow slanted eyes, flat nose and short stature. In addition, there are other health problems throughout the body, consisting in part of cardiac defects and thyroid function abnormalities along with nutritional disorders (ie. overweight, obesity, hypercholesterolemia and deficiencies of vitamins and minerals). Those suffering DS have widespread body frame abnormalities and impaired brain development and function; the latter leading to impaired intellectual development. Many studies indicate excessive or deficient nutrient uptakes associated with making inappropriate foodstuff choices, food intolerance, (eg. celiac disease) or malabsorption. DS persons with overweight or obesity are linked with a slow metabolic rate, abnormal blood leptin concentrations and exhibit low levels of physical activity. Vitamin B group deficiencies and abnormal blood homocysteine levels decrease the rate of intellectual development in DS cases. Zinc deficiencies result in short stature, thyroid function disorders and an increased appetite caused by excessive supplementation. Scientific advances in the research and diagnosis of DS, as well as preventing any associated conditions, have significantly increased life expectancies of those with this genetic disorder. Early dietary interventions by parents or guardians of DS children afford an opportunity for decreasing the risk or delaying some of the DS associated conditions from appearing, thus beneficially impacting on their quality of life.

  6. The Indian Mineral Development Act.

    ERIC Educational Resources Information Center

    Houle, Antoinette

    1986-01-01

    Discusses the objectives of the Indian Mineral Development Act of 1982 (IMDA) and the possible effects it may have on Indian mineral development. Explains how the provisions of IMDA work to provide Indian tribes with greater flexibility for the development and sale of their mineral resources. (ML)

  7. 76 FR 6110 - Conflict Minerals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    .... 34-63793; File No. S7-40-10] RIN 3235-AK84 Conflict Minerals AGENCY: Securities and Exchange... 1934 (the ``Exchange Act'') and would require any such issuer for which conflict minerals are necessary... that issuer to disclose in the body of its annual report whether its conflict minerals originated...

  8. Major issues in miner health.

    PubMed Central

    Joyce, S

    1998-01-01

    As recently as the last few decades, thousands of miners died in explosions, roof collapses, fires, and floods each year, and lung disease caused by inhaling mineral dusts was ubiquitous. Miners worked virtually unprotected, and were often treated as expendable bodies fulfilling critical roles in this important industry, which in the United States comprises about 5% of the gross domestic product. PMID:9799195

  9. Culture systems: mineral oil overlay.

    PubMed

    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.

  10. Unit: Minerals and Crystals, First Trial Materials, Inspection Set.

    ERIC Educational Resources Information Center

    Australian Science Education Project, Toorak, Victoria.

    This unit, one of a series being developed for Australian secondary school science courses, consists of a teacher's guide, two student booklets, a test booklet, and a student workbook which also contains answers to questions raised in the student booklets, and a answer sheet containing comments on the answers to the questions in the test booklet.…

  11. Reducing miner absenteeism

    SciTech Connect

    Peters, R.H.; Clingan, M.R.; Randolph, R.F.

    1989-01-01

    The U. S. Bureau of Mines has prepared this report on strategies for maintaining high job attendance among underground coal miners because high absenteeism is a threat to miners' safety and seriously hampers productivity. A substantial number of research studies on the effectiveness of various strategies for reducing absenteeism among the employees of nonmining industries have been reported in the literature. These strategies have aimed at improving job attendance through one or more of the following: (1) improving employment procedures, (2) overcoming problems that adversely affect one's ability to attend work, and (3) increasing miners' motivation to attend work. Many of these strategies appear applicable to the mining industry, and are reviewed in the first half of this report. The second half of this report describes how one could develop and implement a program for maintaining high attendance at underground coal mines. The steps include measuring and evaluating attendance levels, formulating attendance goals and an absenteeism policy, developing and implementing an attendance promotion program and periodically going through the preceding steps (known as recycling).

  12. The Erevan howardite: Petrology of glassy clasts and mineral chemistry

    NASA Technical Reports Server (NTRS)

    Nazarov, M. A.; Ariskin, A. A.

    1993-01-01

    The Erevan howardite is a polymict regolith breccia containing xenoliths of carbonaceous chondrites. In this work, we studied glassy clasts, which could be considered as primary quenched melts, and mineral chemistry of the breccia. The study reveals that the Erevan howardite consists of common rocks of the HED suite. However, unique glassy clasts, which are present in some eucritic melts, were identified. The mineral chemistry and the simulation of crystallization of the melts suggest that the compositions of the melts reflect those of some primary lithologies of EPB.

  13. Partition coefficients for rare earth elements in mafic minerals of high silica rhyolites: The importance of accessory mineral inclusions

    NASA Astrophysics Data System (ADS)

    Michael, Peter J.

    1988-02-01

    REE concentrations of mafic mineral separates from high-silica rhyolites measured by INAA are high and variable compared to electron microprobe analyses of the minerals themselves. The mafic phases commonly contain inclusions or have adhering grains of accessory rare earth element (REE)-rich minerals. Optical and electron microscopic observation revealed discrete grains of chevkinite (rare earth titano-silicate) included within clinopyroxenes from the Sierra La Primavera (Mexico) rhyolite, and monazite grains adhering to ortho- and clinopyroxenes from the Bishop Tuff (California). During hand-picking of mineral separates, inclusions are only partly removed. As a result, the magnitude and variability of true mineral-melt partition coefficients for light REE have been overestimated. The true REE partition coefficients of La Primavera and Bishop Tuff pyroxenes obtained by microprobe are only slightly higher than they are in lower-silica rhyolites, and are not as variable as previously thought. The partitioning slope is positive, as in less silicic systems. The relative partitioning behavior of REE in high-silica rhyolites is dominated by crystal-chemical controls and not by liquid structural effects. When a partition coefficient is used for crystallization calculations, adhering phases and inclusions should be retained or the minor phases must be accounted for separately. Alternatively, a bulk distribution coefficient can be calculated using whole rock and glass compositions and the glass mode.

  14. Minerals yearbook, 1992. Volume 1. Metals and minerals. Annual report

    SciTech Connect

    Not Available

    1992-01-01

    This edition of the Minerals Yearbook discusses the performance of the worldwide mineral and materials industry during 1992 and provides background information to assist in interpreting that performance. Content of the individual Yearbook volumes follows: Volume I, Metals and Minerals, contains chapters on virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on advanced materials, nonrenewable organic materials, and nonferrous metals recycling also were added to the Minerals Yearbook series beginning with the 1989, 1990, and 1991 volumes, respectively. A new chapter on materials recycling has been initiated in this 1992 volume. In addition, a chapter on survey methods used in data collection with a statistical summary of nonfuel minerals and a chapter on trends in mining and quarrying in the metals and industrial mineral industries are included.

  15. Minerals yearbook, 1991. Volume 1. Metals and minerals. Annual report

    SciTech Connect

    1991-12-31

    This edition of the Mineral Yearbook discusses the performance of the worlwide minerals and materials industry during 1991 and provides background information to assist in interpreting that performance. Volume 1, Metals and Mineral, contains chapters on virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on advanced materials and nonrenewable organic materials also were added to the Minerals Yearbook series beginning with the 1989 and 1990 volumes, respectively. A new chapter on nonferrous metals recycling has been initiated in this 1991 volume. In addition, a chapter on survey methods used in data collection with a statistical summary of nonfuel minerals and a chapter on trends in mining and quarrying in the metals and industrial mineral industries are included.

  16. Enzymatic mineralization of silk scaffolds.

    PubMed

    Samal, Sangram K; Dash, Mamoni; Declercq, Heidi A; Gheysens, Tom; Dendooven, Jolien; Van Der Voort, Pascal; Cornelissen, Ria; Dubruel, Peter; Kaplan, David L

    2014-07-01

    The present study focuses on the alkaline phosphatase (ALP) mediated formation of apatitic minerals on porous silk fibroin protein (SFP) scaffolds. Porous SFP scaffolds impregnated with different concentrations of ALP are homogeneously mineralized under physiological conditions. The mineral structure is apatite while the structures differ as a function of the ALP concentration. Cellular adhesion, proliferation, and colonization of osteogenic MC3T3 cells improve on the mineralized SFP scaffolds. These findings suggest a simple process to generate mineralized scaffolds that can be used to enhanced bone tissue engineering-related utility.

  17. The enamel protein amelotin is a promoter of hydroxyapatite mineralization.

    PubMed

    Abbarin, Nastaran; San Miguel, Symone; Holcroft, James; Iwasaki, Kengo; Ganss, Bernhard

    2015-05-01

    Amelotin (AMTN) is a recently discovered protein that is specifically expressed during the maturation stage of dental enamel formation. It is localized at the interface between the enamel surface and the apical surface of ameloblasts. AMTN knock-out mice have hypomineralized enamel, whereas transgenic mice overexpressing AMTN have a compact but disorganized enamel hydroxyapatite (HA) microstructure, indicating a possible involvement of AMTN in regulating HA mineralization directly. In this study, we demonstrated that recombinant human (rh) AMTN dissolved in a metastable buffer system, based on light scattering measurements, promotes HA precipitation. The mineral precipitates were characterized by scanning and transmission electron microscopy and electron diffraction. Colloidal gold immunolabeling of AMTN in the mineral deposits showed that protein molecules were associated with HA crystals. The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix. Overexpression of AMTN in mouse calvaria cells also increased the formation of calcium deposits in the culture medium. Overexpression of AMTN during the secretory stage of enamel formation in vivo resulted in rapid and uncontrolled enamel mineralization. Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein. A synthetic short peptide containing the SSEEL motif was only able to facilitate mineralization in its phosphorylated form ((P)S(P) SEEL), indicating that this motif is necessary but not sufficient for the mineralizing properties of AMTN. These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization and suggest a critical role for AMTN in the formation of the compact aprismatic enamel surface layer during the maturation

  18. Evolution of sulfide mineralization on Mars

    SciTech Connect

    Burns, R.G.; Fisher, D.S. )

    1990-08-30

    The presence of komatiitic igneous rocks on Marks, based on geochemical evidence from SNC meteorites and Viking X ray fluorescence analyses of the regolith, suggests that massive and disseminated iron sulfide mineralization occurs near the Martian surface. Analogies are drawn between possible ultramafic Fe-Ni sulfides on Mars and terrestrial pyrrhotite-pentlandite ore deposits associated with Archean komatiites formed during early crustal development on Earth. Partial melting of the mantle as a result of high radiogenic heat production then, extrusion of turbulent high-temperature ultramafic lavas, segregation of immiscible FeS melts during cooling, gravitational settling and fractional crystallization of sulfide minerals in magma chambers or lava flows produced massive and disseminated sulfide mineralization associated with terrestrial komatiites. Comparable processes probably occurred on Mars where, on account of the inferred higher Fe/(Fe + Mg) ratio of the X ray mantle (estimated to contain {approximately}4.5 wt % S), iron-rich basaltic magmas were produced by partial melting at depths and temperatures exceeding 165 km and 1,400{degree}C, respectively. Adiabatic diapiric emplacement of these iron-rich, very low viscosity basaltic melts transported significant concentrations of dissolved sulfur as S{sup 2{minus}} and HS{sup {minus}} from the mantle. Ensuing sulfide mineralization may have been either thinly disseminated within ultramafic lavas erupting over large areas of Mars or concentrated locally at the base of structural depressions. Cumulate ore deposits several meters thick may occur at the base of intrusions or in near-surface magma chambers. The evidence for insignificant plate tectonic activity on Mars and minimal interactions of Martian mantle with crust, hydrosphere and atmosphere has restricted the evolution of sulfide ore deposits there.

  19. Hydrothermal and Diagenetic Mineralization on Mars

    NASA Astrophysics Data System (ADS)

    Ehlmann, B. L.; Quinn, D. P.

    2015-12-01

    Predicted by geophysical modeling, the mineraolgic record of early Mars groundwater has only recently been discovered. First, rover exploration in sedimentary basins reveals diagenesis. At Meridiani, sandstone porosity is occluded by precipitation of secondary sulfates, hematite, and silica. Multiple alteration episodes are indicated by crystal vugs, disruption of preexisting textures by hematite concretions, and grain coatings (e.g. McLennan et al., 2005). At Gale crater, raised ridges in mudstones, interpreted to be early diagenetic features, are crossed by later-emplaced hydrated calcium sulfate veins (e.g. Grotzinger et al., 2014). Waters in Gale were likely circumneutral while jarosite mineralogy at Meridiani implies acidic waters. Second, systems of raised ridges at 100-m scale are observed from orbit in multiple Martian sedimentary rock units. An outstanding example is sulfate-bearing sediments exhumed at the northern margin of the Syrtis Major lavas (e.g. Quinn & Ehlmann, 2015). Polygonal and with no clearly preferred orientation, the ridges rise 5-30 m above the surrounding terrain. Parallel light-toned grooves with dark interiors (indicative of isopachous fills) and jarosite in ridge mineralogy point to mineralization by acidic waters. Third, some mineral assemblages observed from orbit represent the products of subsurface aqueous alteration at elevated temperatures (Ehlmann et al., 2011). These are globally distributed, exposed in scarps and by impact cratering. Mineral assemblages variously include (a) serpentine and carbonate; (b) prehnite and chlorite, and (c) zeolites. Collectively, these datasets indicate that groundwaters were spatially widespread on ancient Mars, contributing to the sustenance of lakes and to the alteration of bedrock to >1 km depths. While the Martian surface may have always been relatively inhospitable, a warmer, wetter subsurface provided a long-term potentially habitable environment. Key outstanding questions remaining include

  20. Structure of initial crystals formed during human amelogenesis

    NASA Astrophysics Data System (ADS)

    Cuisinier, F. J. G.; Voegel, J. C.; Yacaman, J.; Frank, R. M.

    1992-02-01

    X-ray diffraction analysis revealed only the existence of carbonated hydroxyapatite (c.HA) during amelogenesis, whereas conventional transmission electron microscopy investigations showed that developing enamel crystals have a ribbon-like habit. The described compositional changes could be an indication for the presence of minerals different from c.HA. However, the absence of identification of such a mineral shows the need of studies by high resolution electron microscopy (HREM) of initial formed human enamel crystals. We demonstrate the existence of two crystal families involved in the early stages of biomineralization: (a) nanometer-size particles which appeared as a precursor phase; (b) ribbon-like crystals, with a structure closely related to c.HA, which by a progressive thickening process tend to attain the mature enamel crystal habit.